Page 1

The Green Bulding Handbook

South Africa Volume 8

The Essential Guide

ISBN 9-780620-452403

ISSN 0123-456X

07

08 9

780620 452403

R150.00 incl. VAT

GRE ENBU ILDING


G


Thermal Resistance added R- Value:

2

1.5PROFILE m K /W (60mm thick)

POLYKEY

Recommended Installation Procedure: ProductTitle:

PolyKey Cavity Wall Insulation

Sizes: Lx 60/40T mm Density20g/l It is recommended that the340Hx1200 foundation wall Nominal includes Polykey as per

PolyKey

Thermal Resistance added

1.5mK/W(60mmthick)

R-Value: Build the inside Stock Brick Leaf up to required Slab Height.

Recommended Installation Procedure: Install PolyKey insulation

Openings in Polykey “cavity” walls

Elements as the outer Face Brick Leaf is bu 1.1m centres at every 4th course (340mm) to comply to SABS req square metre. Stop outer Leaf one course down to install DPC. Cut P zontal with the top of the outer leaf brick to ensure the DPC is level It is recommended that the foundation wall Door and window openings Title:insulation. PolyKey Cavity Wall Insulation includes Polykey as Product perimeter Door and window openings are formed during Build the inside Stock Brick Leaf up to the construction of the wall. The openings can Sizes: 340H x 1200Lx60/40T mm Nominal Density 20g/l allow the door and window frames to be: required Slab Height. Thermal Resistance 2 added Elements 1.5 as mK /W (60mm thick) as the work progresses so that the • Fitted Install Polykey insulation the R- Value: outer Face Brick Leaf is built up. Include Wall Ties frame is built into, and encased by, the wall. on 1.1m centres at every 4th course (340mm) • Fitted into a preformed opening after the Installation to comply to Recommended SABS requirement of 2.5Procedure: ties wall is built. per square metre. Stop outer Leaf course wall includes Polykey as perimeter insulation. It is recommended that one the foundation down to install DPC. Cut Polykey level on the Frames built into the wall as work progresses Stock Brickleaf Leafbrick up to required Slab Height. horizontal withBuild the the topinside of the outer A bricklayer often has to build in frames as the work proceeds. Theup.frames to ensure the DPC is level. Install PolyKey insulation Elements as the outer Face Brick Leaf is built Include are Wall usually Ties on centres at every coursethe (340mm) to comply to SABS and requirement Install DPC, 1.1m draping from inside4thdown premade of timber they actofas2.5a ties profiper le for square metre. Stop outer Leaf one coursethe down to installopening DPC. Cut PolyKey horicourses to outside. required as the level wallon is the built. The zontal with the top of the outer leaf brick to ensure the DPC is level. Build outside Leaf leaving Weep Holes Holes frames are usually plumbed, squared and held Install Include DPC, draping from inside to outside. at 600mm centres. Brickforce asdown per theincourses position before the brickwork begins, and the wall is built around the frame, encasing Engineers specification. Build outside Leaf leaving Weep Holes Holes at 600mm centres. Include Brickforce as per Engiit within the wall. The Polykey wall Insulation neers specification.

Install DPC, draping from inside down the courses to outside.

Build outside Leaf leaving Weep Holes Holes at 600mm centres. Inc neers specification.

DPC

DP

4

THE GREEN BUILDING HANDBOOK


PROFILE Brick Force Vertical DPC

Frame

PolyKey Insulation Cavity closing brick Wall Tie

Brickwork

Brick Force

Jambs and sills : Jambs

Brick Force

Window jamb - reveal Vertical DPC

Frame

elements areof cutopenings with a wood saw tojambs, fit around Fixing frames toFrame pre-formed openings in Vertical DPC The sides are called with the actual face known as the reveal. PolyKey Insulation theInframes where necessary. cavity walls cavity walls, the reveals can be constructed either square or rebated. The cavity can be This method of building in the frames will Once all the building work leaf is completed, theouter closed atPolyKey the opening thebrick inner towards the Cavity closing Insulationby using a suitable frame or by returning reduce leaf. the amount of plumbing and squaring door and window frames can be fitted and required brickwork is built. fixed in place within the pre-formed openings. Cavity closing brick When as thethe inner leaf abuts the outer leaf, a vertical DPC must be inserted to prevent moisture Wall Tie Brickwork from passing through. The fixing Window of the frames will depend upon jamb - reveal Note: framesJambs Securing in place Wall Tiethe construction specification of the building. Brickwork and sills : DPC should extend the cavity to avoid mortar from bridging. When of, Window jamb - reveal Jambs ThisThe canvertical be achieved by using: Metalinto cramps. The development of, and improvement The sides are must called jambs, with the actual face known as the reveal. 100mm blocks are used, the frames DPC be 150mm. Jambs and sills : of openings This method of securing the makes modern fi xings has led to most frames being Jambs In cavity walls, the reveals can be constructed either square or rebated. The cavity can be useSills of specially designed metal cramps fiframe xed inknown place these types of fithe xings. at theare opening by using a suitable or by returning inner leaf towards outerThe The sides closed of openings called jambs, with the actual face asusing thethe reveal. leaf.the Inficavity walls, reveals constructed square or rebated. The cavity can which xedof to back ofcan thebeframe and either commonest type consists of abeplastic sleeve The are function thethe sill is to shed rainwater from the window frame andtoaway from the wall When the inner leaf abuts the outer a vertical DPC inserted prevent at the opening by using a suitable frameleaf, or by returning themust innerbeleaf towards the outermoisture below.closed If the Sill is small a cavity closer block is bedded below the inner window board to positioned so that the cramp coincides with a which encases a toughened zinc screw. When from passing through. leaf. Note: provide a larger, more solid base on to which to fi   the window board. This must be insulated When the inner leaf abuts the on outer leaf, vertical the DPCxmust be inserted to prevent moisture horizontal joint. The cramp is laid top ofathe screw is tightened the sleeve expands, Thethrough. vertical DPC should extend into the cavity to avoid mortar from bridging. When from passing from the external face. bricks and then the wall is built top it. must besecuring 100mm blocks areon used, theofDPC 150mm. the frame in place. Note: Care must be taken when using this method These types of When plastic plugs are The vertical DPC should extend into the cavity to avoid mortar from bridging. Sills 100mmisblocks are and used, the be that the frame plumb to150mm. do manufactured The function oflevel. the DPC sillFailure ismust to shed rainwater from the windowfrom frame polythene and away fromorthenylon, wall and below. If theoccurring Sill is small aat cavity closer block is good beddedholding below theproperties, inner windowbut board to can be Sills to problems so may lead a later have they Wall sill Tieis to shed rainwater from the window provide a larger, more solid base on to which to fi  x the window board. This must be insulated The function of the frame and away from the wall date when the reveals have to be plastered and aff ected by temperature changes. However, from the external face. below. If the Sill is small a cavity closer block is bedded below the inner window board to the doorsprovide a larger, more solid base on to which to fi  have to be fitted. because they are hidden within a structure or x the window board. This must be insulated from the external face.

DPC

Wall Tie

Wall Tie

Window board

Insulation piece DPC

Window board

Insulation piece DPC force Brick Insulation piece Brick force Brick force

Window head Window head Window head

Insulation piece

Window board

Insulation piece Insulation piece

PolyKey

PolyKey PolyKey

Window sill sill Window

Window sill* Continues on page 34 THE GREEN BUILDING HANDBOOK

5


PROFILE

SHUTTERS CAPE ‌..AT YOUR SERVICE!!!!! Shutters Cape offers an extensive range of Sun Shading Solutions such as Internal Blinds, Awnings, Aluminium & Wood Shutters, Paraflex Umbrellas as well as various types of Security Shutter Products. We are the exclusive South African Agents for high quality Roller Shutters and fully automated External Venetian Blinds manufactured by WAREMA in Germany. You are invited to visit our showroom to view the different products on display and browse through material & colour samples with expert advice is always close on hand.

We look forward to meeting you!!

6

THE GREEN BUILDING HANDBOOK


PROFILE

EXTERNAL VENETIAN BLINDS HOW CAN WAREMA SUNSHADING CONTRIBUTE TO GREEN STAR RATINGS? A good amount of natural daylight and intelligent control of solar radiation are the hallmarks of the new generation of “green” buildings, and increasingly form part of building codes and objectives of organisations. A large portion of the sun’s rays penetrate through glass and is absorbed into the room. This direct radiation effect can cause discomfort for occupants, thus requiring airconditioning to cool down the building. Even on cold days, the sun’s effect (in the form of glare) can become quite uncomfortable. External Sunshading entirely overcomes these issues by means of deflecting a substantial portion of solar radiation and controlling flow of daylight. As a cost saving measure, clear glazing can be used, since it is no longer the glass, but the external Sunshading system, that is controlling the flow the solar radiation. It is common for external blinds to lower room temperatures by around 10 degrees. This means great savings on cooling costs and depending on location may remove the need for cooling altogether. An ideal combination for South Africa’s intense radiation is double glazing (highly effective in preventing winter heat loss) together with external shading to lower the heat gain. Buildings created with these measures enjoy a comfortable and stable temperature all year round. A product like WAREMA external venetian blinds provides complete control over solar gain. The blades are incrementally adjustable and coupled with a WAREMA control system track the path of the sun to optimize the interior condition. When the sun sensor measures that exterior conditions are dull, the blinds are retracted to maximise the penetration daylight!

Benefits: Increase room comfort! Enhance daylight! Save energy costs on cooling & artificial lighting! Reduce building costs! Get Green Star ratings! Unit 5, Nobel Park, Nobel Street, The Interchange, Somerset West Tel: 021 852 8785 | info@shutterscape.co.za www.shutterscape.co.za | Contact Person: Wolfgang Striebeck

THE GREEN BUILDING HANDBOOK

7


The

The Green Building Green Building Handbook South Africa Volume 5 Handbook South Africa Volume 8 The Essential Guide

SALES ADMINISTRATION Wadoeda Brenner PROJECT LEADER Louna Rae

DISTRIBUTION ADVERTISING EXECUTIVES Edward Macdonald Glenda Kulp, Tichaona Meki

EDITOR EDITOR Llewellyn vanWyk Wyk Llewellyn van

PROJECT MANAGER CONTRIBUTORS CONTRIBUTORS CHIEF EXECUTIVE Louna Rae Llewellyn vanWyk, Wyk,Wim Graham Young, Llewellyn van Klunne, Mauritz Lindeque, Dr Dirk Conradie, Gordon Brown Naalamkai Ampofo-Anti, Wim Klunne, Tobias vanMike Aldous, Riaan Green Building Council South Africa, Antoine Perrau, ADVERTISING EXECUTIVES Reenen, Conradie, Tichoana van Wyk,Dirk Tichaona Kumirai, GordonKumirai, Brown Coralie van DIRECTORS Charity Musiyanga Reenen, Steve Szewczuk, Rodney Milford Gordon Brown Tendai Jani PEER REVIEWER Andrew Munyaradzi JaniFehrsen PEER REVIEWER Llewellyn van Wyk Lloyd Macfarlane Naalamkai Ampofo-Anti, Llewellyn van Wyk, CHIEF EXECUTIVE Dr. Joe Mapiravana, LAYOUT & DESIGN Graham Young PRINCIPAL FOR AFRICA & MAURITIUS Gordon Brown Kurt Daniels Gordon Brown LAYOUT & DESIGN DIRECTORS Nicole Kenny& PRODUCTION EDITORIAL PRINCIPAL FOR UNITED STATES Gordon Brown Robyn Brown Smith Andrew James Fehrsen EDITORIAL & PRODUCTION PUBLISHER Lloyd Macfarlane ADMINKenny MANAGER Nicole Suraya Manuel

PROOF READER DIGITAL MARKETING MANAGER Dylan Oosthuizen

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Greenthe Building 8 2015/2016. ISBN No: 620 45240 3. that Editor.Handbook All editorialVolume contributions are accepted on978 the0understanding Volume first published February All rightsallreserved. Nocopyrights part of thisand the8contributor either owns or2008. has obtained necessary publication may be reproduced or transmitted in any way or in any form without permissions. the prior written consent of the publisher. The opinions expressed herein are not necessarily those of the Publisher or the editor. All editorial contributions are IMAGES AND DIAGRAMS: accepted on the understanding that the contributor either owns or has obtained Space limitations and source format have affected the size of certain published all necessary copyrights and permissions.

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THE GREENHANDBOOK BUILDING HANDBOOK THE GREEN BUILDING 9

11


The Ecological Impact of glasswool Insulation Under the United Nations Framework Convention on Climate Change (UNFCCC) and its Kyoto Protocol, South Africa committed to contributing its fair share to global greenhouse gas (GHG) mitigation efforts. South Africa has committed itself to an emissions trajectory that peaks at 34% below a “Business as Usual� trajectory in 2020 and 40% in 2025. It is critical that average global temperatures do not rise above 2 degrees Celsius from pre-industrial levels in order to avoid the most severe social and environmental consequences. Each Built-in ton of Isover glass wool insulation helps us save 6 tons of CO2 every year. The discarded waste glass by industry & households is turned by ISOVER into a valuable raw material. ISOVER glass wool consists by about 80% of recycled waste glass. The other ingredients such as quartz sand, soda ash and limestone are virtually inexhaustible resources. The use of glass wool does not only help meet the Kyoto target but also realize energy-efficient living all around the globe. Just consider: The production of 1 ton of glass wool releases about 0.8 tons of CO2. The annual CO2 savin g that can be realized by building in glasswool amounts to as much as 6 tons. Assuming a useful life of 50 years, we can thus save up to 300 tons of CO2. And this is 375 times as much as the CO2 emission caused by production.

NDG P56557 011 806 6200

When production is based on a natural raw material, the finished product will also qualify as natural and eco-friendly and ISOVER glasswool enhances energy-efficient construction.

Tel: 0860 ISOVER (476837) Fax: 086 673 1088 www.isover.co.za


The

Sustainability and Integrated REPORTING HANDBOOK South Africa 2014

THE GREEN BUILDING HANDBOOK

11


EDITOR’S NOTE

Llewellyn van Wyk Editor

W

riting for the New York Times on the four year ongoing drought in California, Adam Nagourney, Jack Healy and Nelson Schwartz asked whether “punishing drought is forcing a reconsideration of whether the aspiration of untrammelled growth that has for so long been the state’s engine has run against the limits of nature” (New York Times April 5, 2015). Similarly, Professor Werner Sobek , speaking about the ‘active house’ constructed at the Wiesenhof Estate in Stuttgart, notes that the building industry, unlike for example the automotive industry, has not analysed the mass flows that will occur as a result of meeting the demands for housing in the future. He went on to note that the largest consumer of resources in the world has not developed a single institution to determine how big that mass flow will

12

THE GREEN BUILDING HANDBOOK

be and established the existence of the necessary resources and their availability. What both commentaries are addressing is the reaching of limits to growth. This will require the building industry – all of its stakeholders – to develop a radically new approach to design and building. This new approach will have to be based on significantly improving the performance of building in the same way that the automotive industry’s response for radically reduced fuel consumption has been to drive up performance. The construction, operation and maintenance of the built environment is a significant consumer of resources as noted by Edwards in a Rough Guide to Sustainability (2002:10), many of which are not renewable (inter alia steel, aluminium, clay, cement, aggregates). The American


EDITOR’S NOTE Institute of Architects also recognised that “current planning, design, construction, and real estate practices contribute to patterns of resource consumption that seriously jeopardise the future of the Earth’s population” (AIA online). One of the identified interventions to influence resource consumption is building performance design targets. Kisek notes that optimizing performance goes beyond compatibility between the structure, enclosure, interior, and services. It involves, he argues, the assessment of economic, social, and environmental parameters so that performance targets are attained affordably within the skill capacity of the industry. This, he suggests, means that innovation may be defined as achieving better performance and higher quality at less cost over the life cycle of a building (2014:13). In summary he argues that: • “Buildings are systems that must be appropriately integrated by designers to achieve defined levels of performance. • Building science provides a disciplined means of dealing with the physical requirements of buildings that is completely compatible with the architectural design and building construction process. • Innovation in modern architecture relies on building science and the systems approach to ensure that building performance meets the expectations of building owners, inhabitants, and society. • The context for building performance has more recently evolved to include issues of ecology and sustainable development. This expansion of

performance parameters, coupled with increasing consumer expectations, has dramatically increased the complexity of buildings. Performance objectives frameworks and conceptual models have become necessary methodologies to assure all aspects of the integration of well performing building systems have been carefully addressed”. This edition of the handbook speaks to building performance and how it may be determined and achieved in a passive manner. Chapters include developing a response to ecology and resilience; materials and embodied toxicity; the energy/water nexus; degree-days; glass and green buildings; material efficiency; and the application of solar chimneys to aid ventilation and indoor environmental comfort. The transition to performance-based building will not be easy: for industry participants it requires recalibrating our understanding of how buildings are designed and made. Much of that understanding will need to be based on developing new knowledge on building science and environmental science and the relationship between the two. As Hutcheon and Handegord noted back in 1983, “The design of buildings has been, and still is, to a large extent, based on traditional building practice. Changes have been slow and, in the main, have come about through an evolutionary process of trial and error. Building practice has been fundamentally an inheritance from the past, modified by factors such as climate, economy, social habits, local aesthetic values, and local resources of materials and

THE GREEN BUILDING HANDBOOK

13


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EDITOR’S NOTE

skills. The evolutionary process works slowly under the influence of new factors; it is equally slow in rejecting the obsolete. The growth of scientific knowledge has led to great advances in the analysis and rational design of the purely structural functions of a building. There has also been a great deal of development in individual materials and components. As yet, there have been relatively small advances in dealing adequately with all of the combinations of elements and with the complex interrelationships of phenomena involved in the performance of an entire building. The reasons are not hard to find. It is sufficient to note that, even now, contemporary building science draws on the knowledge and experience of almost every branch of engineering science. We have long since past the point where we are content to rely on the ‘trial-by-use’ method of assessing changes in design, materials and construction. Many new and interesting materials, systems and methods of design and construction are offered each year. Those responsible for assessing and screening such new developments realise only too well the relative inadequacy of our present knowledge of the suitability of any given material or method. In addition, our standards of performance are continually being raised. As we reduce our major difficulties in turn, minor ones assume greater relative proportions, and we clamour for their reduction or elimination also, in the name of progress. The increasing state of knowledge appears less and less adequate as the demands upon it increase.” This handbook will strive to play its part in assisting academics, students, practitioners and industry as a whole in developing the new knowledge to make this transition.

Sincerely

Llewellyn van Wyk Editor

THE GREEN BUILDING HANDBOOK

15


T

he debate around sustainable architecture is indeed intriguing and yet paradoxical when put in the context of the twenty first century:- a century of high technological advancement, and yet on the other hand one where researchers, professionals and academics search for sustainable ways and methods of doing business. Trends are emerging within the Built environment of which architects need to take particular cognisance as they strive towards sustainability in architecture. Of critical importance is the innovative use of environmentally friendly building technology. Equally important is an in-depth understanding of the energy efficiency nexus, which although focusing on energy, has repercussions on other areas under the sustainability umbrella, including water saving. Thus the challenge facing architects is to be ever more innovative in their quest to achieve more with less and in this way to attain higher performance buildings. Such buildings, for example, use fewer resources, produce smaller amounts of waste elimination and require less water and energy to function optimally. As architects are principle decision makers in designing buildings, they shoulder enormous responsibility. Our fraternity sets the trends in terms of ensuring buildings are both aesthetically pleasing but also icons of sustainable architecture. Thus as President of the South African Institute of Architects (SAIA), I challenge each member to embrace these daunting, yet exciting challenges helping our generation of architects to leave a legacy of which we can be justly proud.

FOREWORD

Sindile Ngonyama President: South African Institute of Architects (SAIA)

Yours faithfully Sindile Ngonyama President South African Institute of Architects (SAIA)

THE GREEN BUILDING HANDBOOK

17


CONTRIBUTORS

LLEWELLYN VAN WYK

Llewellyn is Principal Researcher at the CSIR. He is a leading thinker and speaker on resilient and sustainable infrastructure and the role of building science. He has been awarded with the CSIR Excellence Award, CSIR Director’s Award, SAIA Project Award, and the Mayor of Cape Town’s Greening of the City Award. He has written a number of policy documents for government, including A National Green Building Framework for SA and the Institutionalization of Innovative Building Technologies for Social Infrastructure Projects in SA.

CORALIE VAN REENEN Coralie van Reenen is a professional architect, currently working as a researcher in the CSIR Built Environment Unit. She has a career background in innovative building technologies and is a Green Star Accredited Professional. She has studied environmental law and also lectures architecture students at the University of Pretoria, having a passion for the interface between humankind and the environment.

DR. DIRK CONRADIE Dirk is a senior researcher in CSIR Built Environment Unit. He originally trained and practised as an architect but later specialised in systems and software related to the built environment. He is currently part of a research group that focuses on predictive building performance analysis. He is involved with planning and maintenance systems and recently also the quantification of the South African climate to support predictive simulation and passive design methods. He can also be viewed as one of the CAD pioneers in South Africa.

GRAHAM YOUNG Graham holds a degree in landscape architecture from the University of Toronto. He is the recipient of numerous industry awards and has published widely on landscape architectural issues. He is a founding member of Newtown Landscape Architects and a senior lecturer at the University of Pretoria where he teaches landscape architecture and urban design. He has been a visiting studio critic at the Universities of Witwatersrand and Cape Town and was invited to the University of Rhode Island as their Distinguished International Scholar.

NAALAMKAI AMPOFO-ANTI Naa Lamkai Ampofo-Anti is a Senior Researcher at the CSIR in Pretoria, South Africa. She focuses on research and development solutions aimed at improving the environmental performance of buildings and building products through life cycle assessment (LCA) applications. Naa Lamkai is a professional architect, born in Accra, Ghana, and educated at the University of Science and Technology, Kumasi, Ghana. She immigrated to South Africa in 1990.She left her position as Chief Architect in Department of Public Works, Mafikeng to join the CSIR

18

THE GREEN BUILDING HANDBOOK


RODNEY MILFORD

CONTRIBUTORS

Rodney Milford is currently Programme Manager; Construction Industry Performance at the Construction Industry Development Board (CIDB), and previously Director of CSIR Building and Construction Technology (Boutek). Rodney has played a leading role in the development of SANS 1544 Energy Performance Certificates for buildings, and is supporting the Department of Energy and of Public Works in the implementation of EPCs.

STEVE SZEWCZUK Stefan Szewczuk holds a BSc Aeronautical Engineering degree and an MSc degree in Mechanical Engineering from the University of the Witwatersrand and an MBA from the Heriot-Watt University in Scotland. He is a Senior Engineer at the CSIR working on projects for the World Bank, UNDP, the Global Environment Facility, the European Union, Global Research Alliance and the Regional Research Alliance.

TICHAONA KUMIRAI Tichaona Kumirai is a researcher at the Architectural Engineering research group of the CSIR. Kumirai has been at CSIR for four years. His research focuses on cutting down conventional energy used for providing indoor thermal comfort conditions in buildings through application of passive techniques. Before joining CSIR, Kumirai lectured Engineering Thermodynamics and Engineering Mechanics at Central University of Technology, Free State where he obtained a Masters degree in Mechanical Engineering.

TOBIAS VAN REENEN Tobias van Reenen is a senior researcher with the Council for Scientific and Industrial Research (CSIR). After serving a decade as a mechanical engineering consultant designing industrial cleanrooms and bio-safety laboratories internationally, he works today primarily on researching the role of buildings in airborne disease transmission and perceptions of indoor comfort.

WIM JONKER KLUNNE Wim Jonker Klunne is a renowned energy expert with an academic background in Civil Engineering and Management. His extensive experience in renewable energy projects, from a technical, financial and socio-economic perspective, provides him with a solid background for technical assistance in this field. Currently Wim is working at the Council for Scientific and Industrial Research (CSIR) in South Africa as senior researcher and involved in a large portfolio of renewable energy and energy efficiency projects.

THE GREEN BUILDING HANDBOOK

19


EVAPCO

THE GREEN BUILDING HANDBOOK

2


CONTENTS 1

From sustainability to resilience: a paradigm shift Llewellyn van Wyk

26

2

Landscape Architecture in transition Graham Young

44

3

Materials and embodied toxicity Naalamkai Ampofo-Anti

54

4

The energy/water nexus Wim Klunne

90

5

Degree-days Tobias van Reenen

104

6

Glass and green buildings Dirk Conradie

112

7

Material efficiency Llewellyn van Wyk

126

8

Solar chimneys in buildings Tichoana Kumirai

142

54

214

THE GREEN BUILDING HANDBOOK

21


CONTENTS 224

142

9

Acoustics and green building Coralie van Reenen

158

10

Accelerating the green agenda through innovative building technologies Llewellyn van Wyk

172

11

Wind turbines Steve Szewczuk

188

12

Energy Performance Certificates in SA Rodney Milford

206

13

Alexander Forbes building Case Study

214

14

Pushing the boundaries and exceeding expectations Case Study

224

15

DEA Head Office Case Study

236

THE GREEN BUILDING HANDBOOK

23


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FROM SUSTAINABILITY TO RESILIENCE A paradigm shift

Llewellyn van Wyk


SUSTAINABILITY TO RESILIENCE

D

1

espite inherent definitional and interpretational difficulties the term ‘sustainability’ is widely used in contemporary economic, social and environmental discourse to describe a desirable endgame. Although the term was popularized in the 1987 report Our Common Future published by the World Commission on Environment and Development (also known as the Brundtland report), its origins can be traced back to the United Nations Conference on the Human Environment held in Stockholm in June 1972 (UNEP). This declaration, although the title refers to the human environment, acknowledged the importance of the environment in achieving human well-being. More importantly, it drew attention to the “growing evidence of man-made harm in many regions of the earth: dangerous levels of pollution in water, air, earth and living beings; major and undesirable disturbances to the ecological balance of the biosphere; destruction and depletion of irreplaceable resources; and gross-deficiencies, harmful to the physical and mental and social health of man, in the man-made environment” (UNEP 1972:1). The Brundtland report penned the now classic definition of sustainable development as “development which meets the needs of the present without compromising the ability of future generations to meet their own needs.”This report was followed by a set of 27 sustainable development principles adopted at the United Nations Conference on Environment and Development in Rio de Janeiro, Brazil in 1992. The conference also adopted Agenda 21, a global plan of action for sustainable development, described in 40 separate chapters with a set of actions. The conference was notable for establishing three seminal instruments of environmental governance: the UN Framework Convention

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on Climate Change (UNFCCC), the Convention on Biological Diversity (CBD), and the non-legally binding Statement of Forest Principles. A further consequence was the creation of the Commission on Sustainable Development (CSD). A number of similar conferences have been held subsequent to 1992, including Earth Summit+5 in 1997; World Summit on Sustainable Development (WSSD) in 2002; and most recently the 2012 Rio+20 conference in Brazil. However, it could be argued that the more recent recognition given to climate change and the work of the Intergovernmental Panel on Climate Change (IPCC) has provided a new impetus to sustainable development, or as Drexhage & Murphy argue, “sustainable development has found a de facto home in climate change” (2010:9). Resilience, on the other hand, is a term that first appeared in literature with regard to material science: it was used as a term to describe the behaviour of timber in warships, and later the behaviour of steel in warships in the 1800s. Its use was connected to the ability of the material to withstand the impact of cannons. It did not appear in ecological literature until Holling applied it in the 1970s “ as a measure of the persistence of systems and their ability to absorb change and disturbance and still maintain the same relationships between populations or state variables” (1973:14). The term has also gained popularity in political discourse and policy, perhaps because of its suggestion of strength, and perhaps because of the more recent actual experience of climate change and its impacts. The ‘environment’ is a broad term and can be described in natural and built (manmade) terms. This chapter relies on the National Environmental Management Act (Act 107 of 1998) definition:


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“Environment means the surroundings within which humans exist and that are made up of – • The land, water and atmosphere of the earth; • Micro-organisms, plant and animal life; • Any part or combination of (i) and (ii) and the inter-relationships among and between them; and • The physical, chemical, aesthetic and cultural properties and conditions of the foregoing that influence human health and well-being.” This chapter examines the relationship between sustainability and resilience.

Sustainability concept and theory

The 1972 declaration (UNEP) contains 26 principles to guide efforts for the preservation and improvement of the human environment. The principles refer to key concepts that have become de facto terms in conservation-based human development policy. The principles contain notions such as ‘protect and improve the environment for present and future generations’; ‘the natural resources of the earth, including the air, water, land, flora and fauna and especially representative samples of natural ecosystems, must be safeguarded’; ‘the capacity of the earth to produce vital renewable resources must be maintained’; ‘management of nonrenewable resources’; ‘halting the discharge of toxic substances and the release of heat’; ‘the adoption of an integrated and coordinated approach to development planning’; and the ‘application of science and technology to the identification, avoidance and control of environmental risks’. More critically the principles focused attention on single biological resources such as fishery, the interdependencies

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of multi-resource ecosystems, and the complexity of economic-social-physical settings. It also raised a number of challenging issues, such as the right to a healthy and productive environment, intergenerational implications of resource use, contemporaneous socio-economic equity, time horizons, and the dependence of humanity on Nature. Essentially, sustainable development is predicated on a convergence between economic development, social equity, and environmental protection – also known as the three pillars of sustainable development. In its content it is fundamentally growth focused where growth is understood to be economic – but argues that growth must be fair (equitable) and not cause harm to the environment (Drexhage and Murphy 2010). While in application it has been compartmentalised as an environmental issue, the guiding principle is interpreted as ‘do least harm’ otherwise euphemistically known as ‘the precautionary principle’. As noted by Drexhage and Murphy (2010:2) the “problem with such an approach is that natural resources are in imminent peril of being exhausted or their quality being compromised to an extent that threatens current biodiversity and natural environments”. Perhaps sustainability theory’s most spectacular failure is its inability to change patterns of consumption and production – despite its efforts in this regard. In developed countries gross domestic product (GDP) remains the yardstick for measuring economic performance and is reliant on consumerism, while in developing countries high levels of unemployment and poverty make millions of people dependent on accessing natural resources, legally and illegally. Both actions depend on access to resources with the difference being

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that developed economies are essentially depleting non-renewable resources (mining, fossil fuels) while in developing economies communities are depleting renewable resources (forestry, fishery). Again, both actions share a common outcome: undermining of biodiversity and natural environments. While there have been some sustainable development successes – most notably the results of the Montreal Protocol – unsustainable trends continue. Drexhage and Murphy (2010:16) ascribe this to the following issues: • The concept remains too amorphous to be clearly defined, and hence implemented. • Sustainable development remains fundamentally an environmental issue. •  Sustainable development has been subject to competing agendas. •  D evelopment as economic growth continues to be the dominant paradigm. • Developed countries have not met commitments to developing countries, generating an atmosphere of distrust. • Sustainable development has not been able to find political entry points to make real progress.

Resilience concept and theory

Resilience was historically used to describe the ability of a material to withstand shocks. It was not until 1973 when its definition broadened from its engineering and material background to encompass ecology, and to include the ability to adapt as well as withstand shocks. As Fiksel (2006:16) notes, “resilient systems, including biological and socioeconomic entities, are able to survive, adapt, and grow in the face of uncertainty and unforeseen disruptions”. Central to resilience theory is the acknowledgement that “a perturbation

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can bring the system over a threshold that marks the limit of the basin of attraction or stability domain of the original state, causing the system to be attracted to a contrasting state” (Folke et al. 2010). Folke et al (2010) stresses that this is qualitatively different from returning to the original state, an observation that Holling recognized in the 1996 definition. Holling (1973:1) noted that “individuals die, populations disappear, and species become extinct”. So it may be that some species do not survive: a disturbance of significant impact may well result in the extinction of a dominant species which allows a new species to enter that domain. Change is an integral part of growth and development and can have either positive or negative outcomes. It can be argued that extreme environmental changes can push an ecosystem beyond its capacity to cope, yet even in instances where changes have resulted in extinction, extraordinary ecosystem growth has occurred afterwards. There is an argument that mass extinctions have sometimes accelerated the evolution of life on earth (van Valkenburgh 1999). Figure 1 indicates the growth in the number of specie types over the past 545 million years despite (or perhaps because of ) the five major extinction types (shown in red triangles).

Figure 1: Specie types and major extinction events (Source: Wikipedia 2014)

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Fiksel (2006:16) argues that “the sustainability of living systems – including humans – within the changing earth system will depend on their resilience”. However, it may be that the current rate of species loss will make it difficult for species to recover, or for new species to access previously dominated areas. Estimates of current species loss range from 4 000 to 6 000 per annum, making it the largest species loss since that of the dinosaurs 65 million years ago at almost 1,000 times the background rate of extinction (Quammen 1998). Again, as Gunderson et al. note, ecological resilience is different from engineering resilience. In the latter, resilience is the time it takes to return to a global equilibrium after a disturbance while in the former it is “the amount of disturbance that a system can absorb before it changes state” (2002:3). The latter view implies only one stable state, whereas the former view is based on “the demonstrated property of alternative stable states in ecological systems” (2002:3). Central to resilience theory is the acknowledgement that “a perturbation can bring the system over a threshold that marks the limit of the basin of attraction or stability domain of the original state, causing the system to be attracted to a contrasting state” (Folke et al. 2010:16). Folke et al (2010) stresses that this is qualitatively different from returning to the original state, an observation that Holling recognized in the 1996 definition. Folke et al. (2010) argue that there are three aspects central to resilience thinking: resilience, adaptability, and transformability. Resilience is the tendency of change to remain within a stability domain, continually changing and adapting yet remaining within critical thresholds. Folke et al. (2010) refers to Berkes et al. (2003:393) argument that adaptability “captures the capacity of a system to learn, combine experience and

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knowledge, adjust its responses to changing external drivers and internal processes, and continue developing within the current stability domain or basin of attraction”. Folke et al. goes on to describe transformability as “the capacity to transform the stability landscape itself in order to become a different kind of system, to create a fundamentally new system when ecological, economic, or social structures make the existing system untenable” (2010:16).

The sustainability resilience nexus

Sustainability theory and resilience theory are both fundamentally concerned with the environment where ‘environment’ is understood in the context of the National Environmental Management Act (Act 107 of 1998). Both theories acknowledge the importance of the environment in achieving human well-being. Both draw attention to the “growing evidence of man-made harm in many regions of the earth: dangerous levels of pollution in water, air, earth and living beings; major and undesirable disturbances to the ecological balance of the biosphere; destruction and depletion of irreplaceable resources; and gross-deficiencies, harmful to the physical and mental and social health of man, in the man-made environment” (UNEP 1972:1). Sustainability theory and resilience theory both embody integration, and “understanding and acting on the complex interconnections that exist between the environment, economy, and society” (Drexhage and Murphy 2010:6).

The sustainability/ resilience disconnect

Unlike resilience theory, sustainability theory attempts to distil an amorphous concept into three neat pillars, i.e. economic, social and environmental sustainability.

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PROFILE * Continuation of pg 5

External Corner

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Unlike resilience theory sustainability theory is fundamentally growth focused where growth is understood to be economic. Sustainability theory foresees endless (economic) growth, and posits that this is achievable if a certain behaviour is maintained (do least harm). Unlike resilience theory sustainability theory introduces the concept of ethics into environmental preservation through its intergenerational commitment and its desire for social fairness. It also introduces the concept of human rights through its acknowledgement of the right to a healthy and productive environment. Unlike resilience theory, sustainability theory has, as a guiding principle, the ‘do least harm’ approach otherwise euphemistically known as ‘the precautionary principle’. Perhaps sustainability theory’s most spectacular failure is its inability to change patterns of consumption and production – despite its efforts in this regard. However, the biggest flaw in sustainability thinking is the assumption that steady state equilibrium can be achieved. Sustainability assumes that, providing certain measures are put in place particularly consumption and production processes, growth will be continuous into the future. In theory, steady state systems have numerous properties that are unchanging in time. Sustainability thinking discounts uncertainty and unforeseen disruptions. However past experience indicates that the earth is not in a steady state although there may be times when it is in an apparent state of equilibrium. The earth is subject to dynamic spatial and temporal changes on an ongoing basis, with a wide range in the rate and frequency of these changes. Some of the changes are of sufficient magnitude to significantly alter the state. As Fiksel argues, “force of change, such as technological, geopolitical, or climatic shifts

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will inevitably disrupt the cycles of material and energy flows” (2006:16). Gunderson et al. (2002) argues that the difference between engineering resilience and ecological resilience is the first focuses on maintaining efficiency of function while the second focuses on maintaining existence of function. They argue that the two are so fundamentally different that they become alternative paradigms. Resilience theory, in contrast, is predicated on disruption and the possibility of a new development trajectory. Resilient systems, including biological and socioeconomic entities, are able to survive, adapt, and grow in the face of uncertainty and unforeseen disruptions and it is this adaptive capacity which may lead to new equilibria, a precondition for sustainability.

Discussion

Out of the above, a number of difficulties arise. The first difficulty has to do with the temporal and spatial lens with which sustainability is viewed. Contemporarily, sustainability is viewed as the potential for the human species to live and thrive forever i.e., the intergenerational commitment. This chapter has argued that species have come and gone, and – in the absence of a religious view – there is no ecological reason why homo sapiens too could not become extinct, just as their predecessor hominids did. Using the argument that the emergence of homo sapiens occurred during a time of dramatic climate change 200,000 years ago (Smithsonian Institute 2014), a case could be made for a similar evolutionary step to occur sometime in the future, especially if the earth is heading for (or is already in the process of ) a sixth extinction. The notion that sustainability is the key to be able to proceed indefinitely into the future becomes even more problematic given the projected lifespan of the sun. It is thought that the sun formed about 4.567 billion years ago and is

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roughly halfway through the most stable part of its life (Williams 2013). However, long before that occurs, earth’s water “will evaporate making it inhospitable to all known terrestrial life” (Schroder and Smith 2008). Thus the notion of what is sustainable changes pending the spatial and temporal scales employed. Perhaps sustainability only exists at the scale of cosmic inflation. The second difficulty arises from the way that sustainability efforts generally focus on a single entity or industry: a business will report about its annual sustainability performance, or an industry sector, transport for example, will speak about the goal of sustainable transport, but it is unrealistic to perform an analysis of sustainability in the absence of the broader supporting environment. Setting boundaries for analysis is and remains a formidable challenge. More critically, the third difficulty arises in the manner that sustainability theory

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discounts uncertainty and unforeseen disruptions. Global environmental change includes both systemic changes that operate globally through the major systems of the geosphere-biosphere, and cumulative changes that represent the global accumulation of localized changes (Turner et al. 1990). As Fiksel argues, to better understand sustainable systems, the field of biocomplexity is being pursued: this is concerned with “characterizing the interdependence of human and biophysical systems. It is necessary to study the links among industrial systems (energy, transportation, manufacturing, food production), societal systems (urbanization, mobility, communication), and natural systems (soil, atmospheric, aquatic, biotic), including the flows of information, wealth, materials, energy, labour, and waste” (2006:16). He notes that it is the “complexity, dynamics, and nonlinear nature of these

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interdependent systems” (2006:16) that makes the notion of sustainability unrealistic. Fiksel suggests that systems must be designed to be inherently resilient by “taking advantage of fundamental properties such as diversity, efficiency, adaptability, and cohesion” (2006:17). The United States Environmental Protection Agency (EPA) proposes a new scientific framework that adopts a more systematic and holistic approach to environmental conservation and preservation that takes the complex nature of environmental issues into account. Its Sustainability Research Strategy (2007:40) encompasses several important challenges: • Addressing multiple scales over time and space. • Capturing system dynamics and points of leverage or control. • Representing an appropriate level of complexity. • Managing variability and uncertainty. • Capturing stakeholder perspectives in various domains. • Understanding system resilience relative to foreseen and unforeseen stressors. The fourth difficulty arises with the emerging notion that the development of resilient, adaptive systems is required for achieving sustainability. Given the likely future of this planet, sustainability within the context of this essay is only applicable at a specific spatial and temporal scale.

Conclusion

Anthropological activities, which include land use changes and greenhouse gas emissions, have changed and continue to change the surroundings in which humans and other species live. Global environmental activities, which include climate change and extreme weather events, also change the surroundings in which humans and

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other species live. Global environmental change includes both systemic changes that operate globally through the major systems of the geosphere-biosphere, and cumulative changes that represent the global accumulation of localized changes. The natural and built environments will, in turn, react to and influence these changes in different ways: however, both systems are sensitive to variability and while some of these changes may be beneficial, others may represent a serious threat to species survival. As Fiksel (2006:17) argues “it is necessary to move beyond a simplistic ‘steady-state’ model of sustainability”. In its place must be developed policies rooted in the dynamic interdependencies of species including the recognition of the dependency of homo sapiens on his surroundings, aimed at adaptation and mitigation, and derived from and supportive of ecosystem functions. Folke et al. (2010:16) make a powerful case when they argue that: transformations do not take place in a vacuum, but draw on resilience from multiple scales, making use of crises as windows of opportunity, and recombining sources of experience and knowledge to navigate social–ecological transitions from a regime in one stability landscape to another. Transformation involves novelty and innovation. Transformational change at smaller scales enables resilience at larger scales, while the capacity to transform at smaller scales draws on resilience at other scales. Thus, deliberate transformation involves breaking down the resilience of the old and building the resilience of the new. As the Earth System approaches or exceeds thresholds that might precipitate a forced transformation to some state outside its Holocene stability domain, society must seriously consider ways to foster more flexible systems that contribute to Earth System resilience and to explore options


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for the deliberate transformation of systems that threaten Earth System resilience At its most fundamental level the human species must shed itself of its perceived privileged species status, and acknowledge that as a species we are equally vulnerable to disruption and shock. Only once homo sapiens realise that their resilience is inseparable from ecosystems’ resilience, will policy focus on enabling society to cope

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with unexpected challenges and to adapt to changing circumstances, recognizing that those changed circumstances may be significantly different from what came before. To paraphrase Robin Williams in the movie Dead Poet Society, “That the powerful play ‘goes on’ and you may contribute a verse”: only in the context of this chapter the stage and the actors may well be different.

References • • • • • • • • • • • • • • •

 erkes, F., Colding, J. and Folke, C. editors 2003. Navigating social-ecological systems: building B resilience for complexity and change. Cambridge: Cambridge University Press. Carpenter, S., Walker, B., Anderies, J., and Abel, N. 2001. “From metaphor to measurement: Resilience of what to what?” Eco-systems, 4(8):765-781. Drexhage, J. and Murphy, D. 2010. Sustainable development: from Brundtland to Rio 2012. New York: United Nations. Folke, C., Carpenter, S., Walker, B., Scheffer, M. and Rockstrom, J. 2010. “Resilience thinking: integrating resilience, adaptability and transformability.” Ecology and Society, 15(4):20. Fiksel, J. 2006. “Sustainability and resilience: toward a systems approach.” Sustainability: Science, Practice, and Policy, 2(2):14-21. Gunderson, L., Holling, C., Pritchard, L. and Peterson, G. 2002. “Resilience”. The Earth system: biological and ecological dimensions of global environmental change, 2:530-531 in Encyclopedia of Global Environmental Change. Holling, C. 1973. “Resilience and stability of ecological systems”. Annual Review of Ecology and Systematics, 4:1-23. Quammen, D. 1998. Planet of weeds. [Online] Available from: http://www.uvm.edu/~jbrown7/ envjournalism/Planet%20of%20Weeds.pdf [Downloaded: 2014-12-10]. Schroder, K. and Smith, R. 2008. “Distant future of the Sun and Earth revisited.” Monthly Notices of the Royal Astronomical Society, 386(1):155. Smithsonian Institute 2014. What does it mean to be human? [Online] Available from: http:// www.humanorigins.si.edu/evidence/human-fossils/species/homo-sapiens [Accessed: 2014-1207]. Turner, B., Kasperson, R., Meyer, W., Dow, K., Golding, D., Kasperson, J., Mitchell R. & Ratick, S. 1990. “Two types of global environmental change: definition and spatial-scale issues in their human dimensions.” Global Environmental Change, 1(1):14-22. UNEP 1972. Declaration of the United Nations Conference on the Human Environment. Stockholm: United Nations Environment Programme. Van Valkenburgh 1999. “Major patterns in the history of carnivorous mammals.” Annual Review of Earth and Planetary Sciences, 27:463-493. Williams, D. 2013. Sun fact sheet. [Online] Available from: http://www.nssdc.gsfc.nasa.gov/ planetary/factsheet/sunfact.html [Accessed: 2014-12-07]. Wikipedia 2014. “Specie types and major extinction events.” [Online] https://www.google.co.za

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Email: wayne.miller@bluescope.com


LANDSCAPE ARCHITECTURE IN TRANSITION

Graham A. Young PrLArch

“Humans’ survival as a species depends upon adapting ourselves and our…settlements in new, lifesustaining ways, shaping contexts that acknowledge connections to air, earth, water, life, and to each other, and that help us feel and understand these connections, landscapes that are functional, sustainable, meaningful, and artful.” (Spirn:26)


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wo thousand years ago, Pliny the Younger in his letters described how to locate a villa in order to take advantage of views, cooling winds, and the spatial qualities of the landscape. He was practicing what we today call landscape architecture. Around 1240 AD the ancestors of the Shona people established Thulamela (‘the place of giving birth’) a stone ‘city’ on a promontory of land next to the Luvuvhu River in Limpopo Province, South Africa. Were the makers of this site, in leaving traces on the land, practicing landscape architecture as well? And 2 000 years before Pliny, unknown worshippers raised monolithic stones into a symbolic ship at one of the most spectacular sites along the south Swedish coast. Anderson (2012:32) suggests that “the makers of this site, which is called the Stones of Ale, were leaving traces on the land, practicing landscape architecture as well”. These examples demonstrate that the profession has a history as old as mankind and furthermore Anderson says, “[have] the capacity to affect the inner as well as physical aspects and utilitarian as well as spiritual questions. In that sense, landscape is the media through which our culture, tradition, and identity must be formed, evaluated, questioned, and interpreted” (2012:32). In the span of 4 000 years, 20 years is just a blink of the eye. Nevertheless, the change in the last 20 years has been more rapid than any period before us and includes every aspect of society; science, politics, and not least environmental and landscape design issues.

About Landscape

The concept of landscape has multiple meanings and many different disciplines are involved in its study. According to Antrop (2014) “the origin of the word landscape comes from Germanic languages. One of

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the oldest references in the Dutch language dates from the early thirteenth century and ‘lantscap’ (‘landschap’) refers to a land region or a specific environment. It is related to the word ‘land’, meaning a particular territory, but its suffix scap or scep refers to land reclamation and creation, as is also found in the German ‘Landschaft’ (‘schaffen’ = to make) (Zonneveld, 1995), and also to the English –ship, pointing to a relationship (Olwig, 2002). In the 16th century the concept is broadened and includes a historical region or territory as well as the visual aspects that characterises it. The shift in meaning from ‘organised territory’ to ‘scenery’ is obvious. Olwig (1996) argued that landscape need not be understood as being either territory or scenery; it can also be conceived as a nexus of community, justice, nature, and environmental equity’ Thus, landscape is also the scene of action and an expression of human ideas, thoughts, beliefs and feelings. Watermann (2009:8) elaborates on the theme by suggesting that “all living things are interdependent and the landscape is where they all come together. Context is social, cultural, environmental and historical; amongst other considerations”. At a time when our urban areas are increasingly developed in an ad-hoc project modus, the widespread (re)emergence of landscape as a lens to first understand our cities and then to mediate (design) is indicative of a paradigmatic shift. “Indeed”, says Shannon (2011:626) “over the course of the twentieth century, there has been a change from landscape as a negotiated condition between ‘natural’ and ‘artificial’, towards landscape as a richer term, embracing urbanism, infrastructure, strategic planning, architecture and speculative ideas; landscape has evolved from the pictorial to the instrumental, strategic and operational”.


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Jodidi (2012:6) focuses on the relationship between architecture and landscape when he explains, “architectural realizations that take into account their natural setting may not be considered landscape architecture per se, and yet it is the integration of the two elements (landscape and architecture) that makes the grandeur of many of the bestknown historic realizations. Those who have stood on the remnants of the Great Wall of China near Beijing, … can fully appreciate how the Wall snakes through hills and valleys, forcibly shaped its location and the natural setting”. Local examples would be the ruins at Great Zimbabwe and Thulamela where architecture and its natural setting merge to form a ‘new’ landscape, one where culture and nature have expressed themselves in a beautiful, symbiotic and spiritual relationship. “Landscape architecture”, Jodidi (2012:6) argues, “is [therefore] defined not only as the formation of gardens but also of buildings that have an intimate relation with nature, that in some sense spring from the earth and give meaning to space and materials. Perhaps it would be best to speak of the architecture of landscape despite accepted usage that often excludes buildings from the definition of landscape architecture. It is the Scotsman Gilbert Laing Meason (17691832) who invented the term landscape architecture. His book The Landscape Architecture of the Great Painters of Italy (1828) [explained] how buildings are placed in their sites to produce beautiful compositions. In this sense, the very origin of the term landscape architecture does, indeed, take into account buildings”. The degree of integration of actual architecture with landscape varies according to circumstances and sometimes makes it difficult to distinguish one from the other. Each building or park has its circumstances. Jodidi (2012:8) asks “might not the ultimate

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goal of landscape architecture be to break the (artificial) barrier that separates it from the domain of the builders of towers and bridges? In any case, no less a figure than Frank Lloyd Wright had a clear opinion about this debate: “Change is the one immutable circumstance found in landscape. But the changes all speak or sing in unison of cosmic law, itself a nobler form of change. These cosmic laws are the physical laws of all man-made structures as well as the laws of the landscape. Man takes a positive hand in creation whenever he puts a building upon the earth beneath the sun. If he has a birth right at all, it must consist of this: that he, too, is no less a feature on the landscape than the rocks, trees, bears, or bees, than nature to which he owes his being. Continuously nature shows him the science of her remarkable economy of structure in mineral and vegetable constructions to go with the unspoiled character everywhere apparent in her forms” (in Jodidi 2012:8). It is man who shapes landscapes all over the globe, often changing them irrevocably. Just as landscape belongs broadly to a state of constant flux and change, so too does the profession of landscape architecture. Robert Schafer (2013:3) suggests that the “dazzling concept of landscape demonstrates that it is really important to continuously review the contents of landscape architecture”. “After all”, he says, “it is the very lifeblood of the profession to address the changing landscape, and the ever changing societal needs and issues”. However, landscape architects must accept that no single profession has sole claim on the landscape. “We have high aspirations for the landscape in every respect, we call it productive because it must deliver: drinking water, food, living space as well as contemplation. One would think that if landscape is an expression of

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culture, then culture would let us treat it with care and consideration. However, this is not the case. Although landscape has different meaning for people in the various regions of the world, the global threat to our resources have concentrated our joint focus on the actual situation” (Schafer 2013:3). While in Europe and the USA the profession can look back on a long history, landscape architects in many other countries including South Africa are only just beginning to organise themselves as an interdisciplinary planning and design profession that has integrative skills. According to Schafer (2013:4) “The tasks facing landscape architects have become extremely diverse and it is obvious that they can only be addressed in association with other specialists. The limited perception of the profession as landscape design, which among other things has led to landscape urbanism, is at least partially true. It really comes down to the landscape. And landscape includes everything, not only the undeveloped region on the outskirts of the city”. Waterman (2009:8) elaborates on this theme when he says that “landscape is anywhere and everywhere outdoors. Landscape architecture involves shaping and managing the physical world and the natural systems that we inhabit. Landscape architects do design gardens, but what is critical is that the garden, or any other space, is seen in context. All living things are interdependent and the landscape is where they all come together. Context is social, cultural, environmental and historical, amongst other considerations. Landscape architects are constantly zooming in and out from the details to the big picture to ensure that balance is maintained.”

New Approaches

Because landscape architects design the setting for the built environment it’s not

LANDSCAPE URBANISM

unsurprising then, that a new consciousness has crept into the design of landscapes - an awareness of the fragile environment and sensitivity to the natural environment and its ecological limits. No longer can landscapes be made in a vacuum, but rather they must be resilient by relating and responding to their context in all its respects. Sustainable design requires regenerative, ecologically based strategies to create landscapes that do not alter or impair but instead help repair and restore existing site conditions. These strategies apply to all landscapes, no matter how small or how urban. This new awareness suggests an approach that is somewhat different from conventional landscape design. Birkland (2002:2) suggests that “what is required is a move from traditional ‘remedial’ approaches to preventative ‘systems design’ solutions that restore the ecology, foster human health and prioritise universal well-being over private wealth accumulation. … Instead of applying generalised analyses, goals, criteria, techniques and indicators to any situation (as did ‘modernism’ in architecture) the design of appropriate casespecific, problem solving tools should form a fundamental part of the design process”. Birkland (2002:4) also offers designers a challenge; “If we begin to understand the landscape as our terrain, as the place where we live our lives, then we can see the spectrum of our competence and our responsibility. It may be that at some point it won’t matter whether good planning is carried out by a landscape architect or by a member of another profession. What is important, in the long run, is that we shape our environment in a sustainable manner”. Amidon (2012) argues that economically, global imbalances between abundance and scarcity have set the stage for contemporary landscape architectural practice to focus on strategic resource allocation (and

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LANDSCAPE URBANISM

2

re-allocation) instead of singular solutions by using landscape to maximize a client’s fiscal, spatial and infrastructural assets and by re-imagining one system’s externalities (such as a city’s vacant lots) as another system’s commodity (say, open space for a network of recreation, habitat and storm water management). Amidon (2012:18) states that “ecologically, current design models are process-based, temporally active, structurally adaptive and multi-scalar. Sites, systems and contexts are understood in terms of granularity, edges, adjacencies, connectivity, inputs/outputs/exchanges and performance capacity. They leverage an environment’s aptitude for flexibility. They engineer material performance to have appearance and effect and they incorporate thinking from the increasingly overlapped fields of design, computation, biology, business, health and security”. Of primary interest is how designers create frameworks for change; ecological, social and economically influenced models that provide different ways to conceptualize design and development leading to regenerative solutions. These models and strategies must respond to the increasingly complex scope of projects that contain questions which can’t be definitively answered in a one phase project or budget cycle, as well as the growing influence of landscape ecological thinking emphasizing resilience and controlled adaptivity in the built environment. Amidon (2012:19) maintains that although adaptive re-use, remediation and revitalization have become components of almost every project, “moments of transition are still a somewhat uncomfortable place to be culturally. Disturbance, which ecologists and economists assure us is productive, is painful in social spheres. So, while these principles are enthusiastically explored in critically oriented design, planning

50

THE GREEN BUILDING HANDBOOK

and theory circles, in practice and public perception the work is embryonic. The challenge of this generation [of landscape architects] is to avoid the determinism of earlier ecological design movements, and, using the tools of today, to maintain speculative and aesthetic capacities in both content and communication”.

Conclusion

Landscape architecture has always been a discipline that morphs … But one which in the 70’s and 80’s stagnated when the ecology vs. design debate was being fought between Peter Walker and his disciples vs. the Ian McHarg brigade. Today we are at a stage where the nature of the problem is so complex, particularly in our urban environments, that no one profession can claim rights to dealing with it alone! Landscape architecture internationally has positioned itself with an integrative role and has led many teams in tackling complex multi-faceted projects. In South Africa we are not there yet, and we have to realize that when dealing with the landscape we have to break down the silos and work together as multi-faceted teams that have the same values and principals as we tackle the enormous problem of our cities, which is where most of our population will soon be living! Moving forward in an era of sustainability, “landscape will continue to emerge as an engine for economic, ecological and social vitalization. Client and consumer-driven priorities such as efficiency, affordability, multi-functionality and resiliency will be balanced within the design and planning of meaningful places. Landscape and urbanism will serve as a laboratory for applied models of economic and ecological change in an energetic return to their deep, tangled roots in the fusion of art, environmental infrastructure and social staging” (Amidon 2012:24).


2

Jodidi (2012:19) places this discussion into poetic perspective by concluding, that underlying most initiatives that concern the landscape, there is a concern for ‘perfection’ that may no longer animate architecture quite so much. This concern is linked to the idea of the garden, symbolizing a world before sin for the Judaeo-Christian traditions, or heaven itself in Islam, for example. Surprisingly, even the current trend to ecological concerns emphasizes the idea of the return to a pristine state, before the fall, as it were. The regenerative power of landscape, or more precisely of nature, inspires this continually renewed hope for the redemption, even in the face of massive destruction of the natural environment for reasons of need or greed. While everything man made can be questioned or subject

LANDSCAPE URBANISM

to moods and fashions, nature has its own legitimacy, and it is a part of this legitimacy that landscape architecture surely seeks. Man-made and yet closer to nature than other forms of expression, landscape architecture, beyond the expression of individual creativity, aspires to redemption, to a return to the initial primitive state. Frank Lloyd Wright may have dreamed of architecture that was inspired by nature, but the fact of contemporary construction is that this is very rarely the case. Art is often inspired by nature, even today, but somehow cannot aspire to any real return to the perfection of what was before the fall. *Although Landscape Architecture has formerly been around since 1970 in South Africa, it has never reached the status it has achieved in other countries like USA, Canada and Australia.

References • • • • • • • • • • • • • •

Amidon, J. 2012. Two Shifts and Four Threads. Topos 80: 18-19. Andersson, T. 2012. Landscape Architecture in Transit. Topos 80: 32 – 42. Antrop, M. 2014. Some background on landscape concepts. Paper presented at the General Assembly of ICOMOS and the Scientific Conference “Heritage and Landscape as Human Values”. Florence, Italy. Birkeland, J. 2002. Design for Sustainability. London: Earthscan Publications Ltd. Jodidi, P. (2012). Landscape Architecture Now. Taschen GMBH, Cologne. Olwig, K.R., 1996. Recovering the Substantive Nature of Landscape. Annals of the Association of American Geographers. Olwig, K.R., 2002. Landscape, Nature and the Body Politic: from Britain’s Renaissance to America’s New World. Madison, University of Wisconsin Press, 299pp. 86(4), 630-653. Richardson, T. 2011. Futurescapes. 1ST ed. Thames & Hudson, London. Shannon, K. ‘Landscapes’. In Crysler, C. G. et al (2011), Architectural Theory. Sage. London. p 626. Schafer, R. 2013. Editorial. Topos 82: 3. Spirn, A.W. (1998). The Language of Landscape, New Haven: Yale University Press. Waterman, T. 2009.The Fundamentals of Landscape Architecture. AVA Publishing, Lausanne, Switzerland. Young, G. 2012. The Green Building Handbook, Volume 4. Alive2Green, Cape Town. Zonneveld I.S., 1995. Land Ecology, SPB Academic Publishing bv, Amsterdam, 199 pp.

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LIVING GREEN WALLS The trend for Green Walls (also known as vertical gardens or living walls) has been around for a while now, but it shows no signs of dissipating. In fact, it seems to be gaining steadily in popularity as more and more businesses and homeowners jump on the green bandwagon. In corporate environments Green Walls provide a soothing and cooling effect, increasing workplace productivity and reducing stress, whereas in urban environments Green Walls are used predominantly to extend limited garden space and liven up dull areas (alley ways and boundary walls), as well as providing a fantastic opportunity to cultivate home-grown herbs and veggies. Although Green Walls remain expensive high-end items, there are numerous different systems available on the market ranging from DIY to fully automated including advanced irrigation, reticulation and fertigation™ systems that allow for a completely customisable fit. At Cape Contours, we are well experienced in the custom design, supply and installation of Green Walls across South Africa and beyond. To request a complimentary consultation, call Cape Contours Landscape Solutions on (021) 788 1202 or visit www.capecontours.co.za

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For more information please visit www.capecontours.co.za or call us on (021) 788 1202 to request a quotation


A BRIEF INTRODUCTION TO CHEMICAL HAZARDS IN THE LIFE CYCLE OF BUILDING PRODUCTS WITH FLOOR COVERINGS AS A CASE STUDY

Naa Lamkai Ampofo-Anti


3

MATERIALS EMBODIED TOXICITY

Buildings play an essential role in the social the management of chemical toxicity and economic advancement of human in buildings as good practice. However, societies. However, modern buildings in practice, the focus of the voluntary contain numerous synthetic, chemically building rating systems, such as Green Star processed and or treated materials, most South Africa, is to limit building occupant of which have never been tested to exposure to volatile organic compounds determine the health hazard status (Liddell (VOCs). This approach however overlooks et al, 2008; AQS, 2010). Given the inordinate building occupant exposure to non-VOC materials demand of the building sector, toxics. Furthermore, it cannot address the the production, use and disposal of modern human and environmental health hazards Abuilding brief products introduction hazards in thelifelife cycle of has cometotochemical play a in the other building cycle stages. central role in the creation of human and The limitation of the current approach to building products with floor coverings as a case study environmental health hazard. chemical hazard management is depicted The types and quantities of building in Figure 1. The rationale for replacing the Naa Lamkai Ampofo-Anti products are constantly on the increase. The current with a new approach Building Science & Technology Competence Area, CSIR Built approach Environment, Pretoria exposure to potentially hazardous chemicals includes: NAmpofoanti@csir.co.za is therefore likely to increase in the absence • Environmental regulation is likely to of an intervention aimed at replacing toxic become more stringent – for example, the European Union and Japan have with benign building products. At the Introduction already adopted mandatory, building beginning of the 20th Century, about 50 and construction-specific frameworks materials were used in buildings (Liddell et Buildings an more essential in the social and economic advancement of human societies. al, 2008).play Now, thanrole 55 000 building which ban, restrict and/or limit chemical However, buildingsand contain chemically processed and life or cycle. treated productsmodern are available, over numerous half are synthetic, hazards in the building product materials, most of which have never been tested to determine the health hazard status (Liddell et al, man-made. • Building activity is likely to continue 2008; AQS, 2010). Given the inordinate materials demand of the building sector, the production, use worldwide into the foreseeable future. The efforts aimed at addressing the and disposal of modern building products has come to play a central role in the creation of human and Replacing toxic with benign building environmental impact of buildings have environmental health hazard. prioritised energy and to some extent, products will therefore limit exposure. The types andExtensive quantities guidance of building products on protect the increase. exposure to materials. is now are• constantly In order to futureThe generations, potentially is therefore likely to increase in the absence an intervention aimed availablehazardous on howchemicals to achieve building the current materialofresource strategies th atwhole replacing withenergy benign and building products. At the beginningand of the 20 would Century, aboutto50 lifetoxic cycle materials of recycle reuse need materials were used in buildings (Liddell et al, 2008). Now, more than 55 000 building products are efficiency. In principle, the key building return benign – not toxic – materials available, and over half are man-made. sector stakeholders have recognised back into the building life cycle. 1 Material extraction and processing

2 Materials manufacturing

3 l On-site construction

4 Operation and maintenance

5 End-of-life

Chemical hazards:

Chemical hazards:

Chemical hazards:

Chemical hazards:

Chemical hazards:

VOCs

VOCs

VOCs

VOCs

VOCs

SVOCs

SVOCs

SVOCs

SVOCs

SVOCs

Heavy metals

Heavy metals

Heavy metals

Heavy metals

Heavy metals

PRE-USE PHASE

USE PHASE

END OF LIFE

Figure 1: chemical hazard can manifest in any form at any stage of the building product life cycle Figure 1: chemical hazard can improvement manifest in any formfocus at any stage of the building inproduct cycle however, efforts mainly on VOC emissions the Uselife Phase however, improvement efforts focus mainly on VOC emissions in the Use Phase The efforts aimed at addressing the environmental impact of buildings have prioritised energy and to some extent, materials. Extensive guidance is now available on how to achieve building whole life GREEN BUILDING HANDBOOK 56 cycle THE energy and materials efficiency. In principle, the key building sector stakeholders have recognised the management of chemical toxicity in buildings as good practice. However, in practice,


3

In the absence of local mandatory provisions addressing chemical hazards in building products, the duty surely falls on the key building sector stakeholders material manufacturers, contractors, built environment professionals—to inform themselves about the extent of the problem in order to avoid or minimise the human and ecosystem health risks. This chapter aims to establish the chemical hazard in building products as a whole life cycle concern for the key actors in the building product supply chain and thereby create an enabling environment for the reduction of the chemical loads on humans and the environment. Section 1 sets out the purpose; and describes the methodology and the scope of the chapter. Section 2 identifies and describes globally accepted health hazard criteria; and the major classes of chemical hazards associated with the building product life cycle. Section 3 uses the health hazard criteria to identify, analyse and categorise chemical hazards in selected building products. Section 4 summarises the findings and also presents an outline of future chapters which will add to and complete the research work presented here. The scope of this chapter is limited to three major South African floor covering materials – ceramic tile, carpet (stretch and tile) and poly vinyl chloride (sheet and tile). The findings for ceramic and PVC products are valid for wall/floor coverings.

Building materials and chemical hazards What is a chemical hazard? The use of chemicals to enhance and improve life is a widespread practice worldwide. The chemical industry converts raw materials such as oil, natural gas, metals and minerals

MATERIALS EMBODIED TOXICITY

into thousands of products many of which are destined for use in buildings. The global production of chemicals has increased from one million tonnes in 1930 to several hundreds of millions of tonnes today – the exact number of chemicals on the market is however unknown as new ones are being introduced each year. However, chemicals are a blessing and a curse (ECHA, 2015a). Many chemicals used to produce every day products may constitute a health hazard to humans and ecosystems at any stage of the product life cycle, from cradle-to-grave. A chemical constitutes a human or environmental health hazard when there is statistically significant evidence based on at least one scientific study that adverse health effects may occur if humans, wildlife or flora and fauna are exposed to the chemical . For all living species, including humans, the health endpoint of greatest concern is exposure to persistent and bio-accumulation toxicants (PBTs). The human-specific health endpoints of concern range from toxicity – arising from exposure to carcinogenic, mutagenic and reproductive (CMR) chemicals, to sensitization – arising from exposure to chemicals of equivalent level of concern (ELoC). The eco-system specific health endpoints of concern include aquatic eco-toxicity and terrestrial eco-toxicity. These human and environmental health categories are elaborated in the sections which follow.

Health hazard categories Persistent and bio-accumulative toxicants (PBTs) Manmade substances that are difficult to breakdown (persist), accumulate in living organisms (bio-accumulate) and are toxic, are generally known as persistent and bio-accumulative toxicants (PBTs) (ECHA, 2015b). PBTs accumulate in plants and

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MATERIALS EMBODIED TOXICITY

3

animals as they travel up the food chain hence the largest quantities of these substances are usually found in humans. Protection of the environment from PBTs is particularly difficult as these substances do not degrade near the emission sources but may be transported into pristine remote areas. A reference to PBTs in the literature is typically preceded by the risk phrase “very high concern”. PBTs of the very highest concern are known as persistent organic pollutants (POPs). These POPs have been banned internationally under the Stockholm Convention on Persistent Organic Pollutants of 2001. The most well-known of the POPs is perhaps DDT which inspired Rachel Carson’s 1962 Silent Spring. Other descriptions of PBTs include very persistent and very bioaccumulative (vPvB), very persistent and toxic (vPT) or very bio-accumulative and toxic (vBT) (Lent et al, 2010). Once PBTs are dispersed in the environment, the risk of exposure is very difficult to reverse.

Case study 1 – PBT in thermal insulation: HBCD

The main reason for significant global production of the flame retardant HBCD, sometimes abbreviated as HBCDD, is its use in expanded polystyrene (EPS) and extruded polystyrene (XPS) rigid insulation boards, which are widely used in the building industry. HBCD was added to The Stockholm Convention’s list of POPs in September 2013. The signatories to The Convention are required to phase out production, importation/exportation and use of HBCD as a flame retardant. The target “sunset” date already set by the European Union is August 2015. An exemption was granted, on appeal by manufacturers, for the main use in EPS/XPS building insulation to continue for a period of five years until September 2018 (ChemicalWatch, 2013).

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In December 2013, the World Wildlife Fund (WWF) DetoX Campaign conducted a biomonitoring study to determine the human blood serum content of 101 predominantly PBT chemicals. The blood samples were taken from 47 volunteers from 17 European countries (WWF, 2013). 13 chemicals were found in the blood of every volunteer tested for that chemical – the details of these chemicals are provided in Table 1. Of the 13 chemicals, eight can be linked to popular floor coverings as shown in Table 1. All eight are SVOCs. All eight are listed under the Stockholm Convention. One of the chemicals, HCB, is a manufacturing by-product which could nevertheless be present in the final product, such as PVC flooring, as a contaminant (Lent et al, 2010, Barber et al, 2005). The remaining seven perfluorinated compounds are commonly used by manufacturers as the active ingredient in stain and water repellents for carpets, paints, and wall/floor coatings. The ‘parent’ of the perfluorinated chemicals is perfluorooctane sulfuric acid (PFOS) also known as perfluorooctane sulfonate. The derivatives or salts of PFOS include MeFOSE and EtFOSE (Weschler and Nazaroff, 2008). In terms of the Stockholm convention Annex B, PFOS, and all its salts, is currently prohibited from use in building products. Box 2 provides more information on the current status of PFOS.

Case study 2 – PBT in floor and wall coatings/coating additives: PFOS

• In December 2002 PFOS was formally identified as a PBT during the 34th meeting of the OECD Chemical committee (CIRS, 2015). • In May 2009, PFOS was added to Annex B of the Stockholm Convention list of POPs. Annex B specifically prohibits the further


3

use of PFOS in carpets and in coatings/ coating additives (this would include varnishes and paints) (CHMPOPs, 2015). • In September 2009, the European Parliament placed a restriction on

MATERIALS EMBODIED TOXICITY

the marketing and use of PFOS and derivatives. PFOS is included on the chemical policy REACH Annex XVII list of restricted chemicals dated September 2012 (SSS EU, 2015).

Chemical of concern

Number of products

% volunteers

Hazard

Use in building product

Probable building product source

HCB

1

100

PBT/POP

Manufacturing PVC floor/ by-product wall covering

PFOS

7

100

PBT/POP

Stain or water repellent

Carpet, floor / wall coating

DEHP

1

100

PBT/POP

Plasticiser

PVC or SBR floor/wall covering

Table 1: Link between common building products; and PBTs found in blood of WWF study volunteers

Building product

Constituent

Chemical of concern

Chemical group

Carpet system

Backing,100% recycled tyre

Naphthalene Lent et al, 2010

VOC

Ceramic tile wall/ floor system

Primary glaze, boron-based

Arsenic Nicoletti et al, 2000

Heavy metal

Linoleum flooring system

Agro-chemical, synthetic fertiliser

E.g. Bromoxynil Lent et al, 2010

SVOC

Synthetic rubber flooring system

Manufacturing content (and emissions)

Styrene Lent et al, 2010

VOC

Manufacturing residual

Aniline Lent et al, 2010

VOC

Table 2: CMR toxicants in the life cycle of major flooring systems

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3 Carcinogenic, mutagenic and/or reproductive (CMR) toxicants Chemicals that are carcinogenic, mutagenic or toxic to reproduction (CMR) are of specific concern due to the long-term and serious effects that they may have on human health (ECHA, 2015c). CMRs are typically identified in the literature by the risk phrase “high concern”. The most hazardous of the CMRs, based on evidence from scientific studies, may be elevated to the same level as PBTs by the risk phrase “very high concern”. CMRs can interfere with DNA – our genetic blueprint – and change it by causing uncontrolled growth of cells (cancer) or cause heritable genetic damage (mutation) or impair fertility (reproduction). As depicted in Table 1, DEHP is one of the 13 substances found in the blood of volunteers who participated in the 2013 WWF Detox Study. DEHP is a plasticiser primarily found in SBR flooring and PVC floor/wall coverings – PVC flooring may contain up to 30% by mass DEHP plasticiser (Weschler and Nazaroff, 2008; Lent et al, 2010). The European Union recently

MATERIALS EMBODIED TOXICITY

classified DEHP as an endocrine disruptor under the chemical policy, REACH; and issued a sunset date of February 2015 for termination of the use of this chemical in most products (QMED, 2014). Table 2 provides examples of CMR toxicants in the life cycle of common building products. Chemicals of equivalent level of concern (ELoC) As compared to the bioaccumulative nature of the PBTs and the generally toxic nature of CMRs, the health concern in respect of ELoC chemicals is sensitisation or specific organ toxicity arising from acute or chronic exposure. A skin sensitizer will produce an allergic response following skin contact. The allergic skin reaction generally disappears when exposure to the sensitising agent comes to an end, although severe reactions can occur. Exposure to a respiratory sensitizer induces a range of reactions from the immune system (ECHA, 2015d). These may vary in severity from coughing and wheezing to development of asthma. The chemicals included in this group can

Example of ELoC chemical

Example of uses in building product

Human exposure pathway

Chemical group

Acid anhydrides – PAN, MA

Epoxy resins, high performance coatings

Breathing, skin contact, contact between food and indoor dust

SVOC

Acrylates – MMA, PMMA

Paints, fluid applied floors, lacquers

Breathing, skin contact, contact between food and indoor dust

SVOC

Formaldehyde

Laminates, insulation, adhesives

Breathing in

VOC

Styrene

Carpets, SBR flooring

Breathing in

VOC

Table 3: ELoC chemicals in the life cycle of common building products

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3

be identified on a case-by-case basis and moved into the previously discussed hazard categories of greater concern where there is scientific proof to allow such reclassification. The chemicals listed in Table 2 serve as an example of chemicals in this hazard category which are known to contribute to asthma or are suspected of contributing to the onset of asthma Eco-system health categories Eco-toxicity is a reference to the impact of toxic substances on freshwater and marine and land-based ecosystems. Eco-toxicity can further be split into the three sub categories, namely, aquatic eco-toxicity, marine ecotoxicity and terrestrial eco-toxicity. Toxic substances do not generally remain in the environmental compartment into which they are emitted, but tend to spread to other compartments, where they may do

MATERIALS EMBODIED TOXICITY

more damage (Guinee, 2002). For example, when a flax or hemp crop, which is destined to be used as carpet fibre, is sprayed with a biocide, some of the airborne spray will eventually end up in local freshwater bodies, causing severe harm to the freshwater species. Furthermore the synthetic fertilisers applied during cultivation of industrial crops almost always result in the emission of a range of heavy metals – copper, cadmium, cobalt, mercury, nickel and zinc – to the soil as a residual after crop uptake (Corbière-Nicollier et al, 2001; van der Werf, 2004). These heavy metals have negative toxicological effects, resulting in eco-toxicity. If food crops were to be planted right after the harvesting of the industrial crops, a significant fraction of the heavy metals will enter the human diet (Corbière-Nicollier et al, 2001).

Chemical of concern

Example of uses in building product

Ecosystem exposure route

Chemical group

Arsenic Mercury

Cement production – (alternative fuels use)

Manufacturing air release South Africa, 2010

Heavy metals

Fluorine

Clay brick, ceramic tile - (natural clay content)

Manufacturing air release, Nicoletti et al, 2000

Halogen

Nickel

Plant-based carpet fibre (synthetic fertiliser use)

Emissions to soil Corbière-Nicollier et al, 2000

Heavy metals

Ag-NP

Ceramic tile – (antimicrobial use)

Emissions to water EC, 2014

Table 4: Example of building product, chemical of concern and eco-toxicity pathway

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3

MATERIALS EMBODIED TOXICITY

Hazardous chemical classes of concern in the building product life cycle

A growing body of research suggests that there are two major groups of hazardous chemicals associated with the building product life cycle – volatile organic compounds (VOCs) and semi-volatile organic compounds (SVOCs). Exposure to a chemical in one of these two groups can result in short or long term adverse effects on human health and comfort. The VOC group has been subjected to extensive research resulting in a heightened awareness about the potential health risks. As compared to VOCs, analytical challenges in measurement have impeded progress in studying SVOCs resulting in limited dissemination of information. This section presents a brief literature survey on the contribution of VOCs and SVOCs to chemical hazard in the building product life cycle.

Volatile organic compounds (VOCs) Volatile organic compounds (VOCs) are a large group of organic chemicals that easily evaporate at room temperature. They are residuals from the manufacturing processes of building products. Within the VOC group, there are very volatile organic compounds (VVOC) that are differentiated from VOCs by their very low boiling point range – this is depicted in Table 5. Due to the generally low boiling point of VOCs, concentrations can increase very rapidly in an enclosed space (REF) and peak within 12 hours. Thereafter, the emission rates decrease drastically. The concentrations of VOCs in indoor air can be up to 10 times greater than outdoors (Lidell et al, 2008). Because they are airborne, the principal pathway for exposure to VOCs is through inhalation. The major building product-related sources contributing to outdoor concentrations of VOCs are manufacturing

Organic compound

Abbreviation

Boiling point range °C

Chemical state

Chemical state Exposure pathway

Very volatile organic compounds

VVOC

0–6

Gas phase

Inhalation

Volatile organic compounds

VOC

6 – 290

Gas phase

Inhalation

Semi-volatile organic compounds

SVOC

290 – 400

Airborne particles

Inhalation Ingestion

Settled dust Ingestion Dermal Table 5: Comparison of exposure pathways of VOCs and SVOCs

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3

releases; and painting activities which involve the use of decorative paints, solvents and varnishes. VOCs released to the external air from these sources combine with nitrous oxide (NOX) in the presence of sunlight to form ground level ozone (USEPA, 2015). Exposure to ground level ozone can trigger a variety of health problems including chest pain and throat irritation. It can worsen existing conditions such as bronchitis and asthma. Ground level ozone is also a health hazard for sensitive ecosystems; and contributes to global warming (Jönsson, 2000). Due to the large surfaces that they represent, building products that are used as finishes for floors, walls and ceilings are the main sources of VOC emissions to indoor air (Levin, 2010). The high VOC concentration in indoor air poses three types of health hazard, namely (Jönsson, 2000): • Perception of odours which affects comfort levels ; • Irritation of the mucous membranes – eyes, nose and throat ; and • Long-term toxic reactions.

MATERIALS EMBODIED TOXICITY

Some jurisdictions have passed regulations to limit the outdoor abundance of VOCs. Examples include the European Union’s Directive 1999/13/EC and the State of California’s South Coast Air Quality Management District (SCAQMD) VOC Regulations. The purpose of VOC regulation is to reduce VOC content – not VOC emissions – and thereby protect human and environmental health. The main strategy aimed at reducing indoor air VOC concentrations is substitution of standard building products with low-emitting building products. For the following reasons, this indoor strategy is less easy to apply, namely: • A VOC test does not cover all VOCs present in the tested building product. This is because VOCs belong to different chemical classes. The air concentrations at which a VOC affects health differs from one class to the other – VOC test results can therefore not be generalised and a test needs to be developed for each class of VOCs.

VOC of concern

Examples of uses in building products

Health hazard

4-PCH

Carpet system

ELoC

Ethyl hexanol

Carpet system

ELoC

Styrene

Carpet system, synthetic rubber flooring

Possibly CMR

Formaldehyde

Particleboard, MDF

CMR

Ethylbenzene

Carpet

CMR

Toluene

Carpet

Possibly CMR

Table 6: VOCs emitted from common building products installed indoors

THE GREEN BUILDING HANDBOOK

65


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• A VOC test does not assess all possible health effects associated with the assessed chemical – the test is concerned with non-cancer issues only. Furthermore, non-VOC hazardous chemicals such as SVOCs may still be present even in products that have been tested, certified and labelled as “low emitting”. Semi-volatile organic compound (SVOC) is a collective term for organic compounds covering a boiling point range of 290-400 °C (Wensing et al, 2005). SVOCs are added to the formulation of building products as flame retardants, plasticisers, antimicrobials/ biocides, stain repellents and waxes/polishes (Weschler and Nazaroff, 2008). SVOCs are also found in a wide range of every day products including electronic devices,

MATERIALS EMBODIED TOXICITY

garden hose pipes, toys, household cleaning products, insecticides and cosmetics. Unlike VOCs, to which people are exposed via inhalation, SVOCs are found in indoor air as gas, airborne particles or settled dust (Wensing et al, 2005). Improved ventilation and selection of low-VOC building products is therefore an effective management strategy for VOCs. Avoiding or reducing exposure to SVOCs in the indoor environment is however much more difficult to achieve because exposure can occur through a variety of pathways: • Inhalation (breathing in airborne particles) or • Dermal contact (skin absorbs dust) or • Ingestion (airborne particles or dust is absorbed by food/drink prior to consumption) or

Additive category

Uses in building products

Additive name / chemical of concern

Biomonitoring data source

Hazard

Stain repellent

Carpets

EtFOSE, MeFOSE

Blood

PBT/POP

Plasticiser (phthalate)

Resilient flooring

BBzP

Urine

ELoC

Plasticiser (phthalate)

Resilient flooring

DEHP

Urine

CMR

Flame retardant

Carpet padding

penta-BDE

Blood

PBT/POP

Flame retardant

Building insulation, ceiling board

TCPP

Flame retardant

Resilient flooring, building insulation

PBDE

Acute toxicity Breast milk

CMR

Table 7: examples of SVOCs and their applications in common building products

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67


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• Combinations of all the three listed above. The difference between the exposure pathways for VOCs and SVOCs is illustrated in Table 5. When released from an indoor source, VOC concentrations normally increase to a high point in the first few hours, followed by a decrease to much lower levels over a few days. By contrast, when released from a source, SVOCs sink/adsorb into nearby surfaces, making it difficult to measure their air concentrations (Horn et al, 2002; Weschler and Nazaroff, 2008; Wensing et al, 2005). Due to this “sink effect” an SVOC can persist for years after the source is introduced into a building. For example, DDT was banned internationally in the 1970s, but continues to have measurable levels in indoor air (Weschler and Nazaroff, 2008) and human blood (WWF, 2013) – thus parallels can be drawn between indoor persistent SVOCs and outdoor POPs (Weschler and Nazaroff, 2008). The majority of SVOCs used as additives in building products are classified as hazardous or must be regarded as potentially hazardous to health. Bio-monitoring studies have revealed high bodily burdens of more than 100 SVOCs. Table 5 provides examples of SVOCs of the highest concern, their applications in building products and the human health risk implications. A number of these chemicals have been removed from commercial use, or have become subject to restricted use (Weschler and Nazaroff, 2008).

Major floor coverings and health hazards

In the South African context, the demand for both resilient and non-resilient floor covering products accounts for about 9% of the market for the major building products. The demand is split over three leading materials as follows (CIDB, 2007):

MATERIALS EMBODIED TOXICITY

• Ceramic tiles – 60% market share. • Carpeting (stretch and tiles) – 30% market share. • Polyvinyl Chloride (PVC) (tiles and sheeting) – 5%. The sections which follow make use of the literature to highlight human and environmental health hazards associated with these major floor coverings and their installation products. Ceramic tiles Ceramic tiles, which are used for both structural and decorative purposes, may constitute 50% of all materials in existing buildings worldwide (Tikul and Srichandr, 2010). Ceramic wall and floor tiles include mosaic, quarry, porcelain and speciality tiles. Although some floor tiles are produced unglazed, the majority of wall/floor tiles are glazed (Nicoletti et al, 2002). The three components of a glazed ceramic tile are the body, which is produced from clay; and the primary and secondary glazes. Open pit clay mining is a highly dusty process. Without adequate control, the fine particulates that are generated pose a health hazard to local people and to wildlife. Clay mining has been shown to cause asthma and silicosis in workers (HBN, 2015a). Furthermore, the atmospheric emissions which occur when clay-based products are manufactured almost always include fluorine which is naturally present in most deposits of clay and shale (Athena SMI, 1998; Nicoletti et al, 2002; HBN, 2015a). The fluorine emissions contribute to acidification of freshwater bodies; and damage to crops and forests. The purpose of the primary glaze is to provide the clay tile with a vitreous coating which is impermeable, hard, durable and easy to clean (Nicoletti et al, 2002). The ceramic tile industry has relied on glazes

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69


3

MATERIALS EMBODIED TOXICITY

made from basic carbonate white lead for hundreds of years. However, white lead and other lead oxides are more soluble than other forms of lead. The lead in ceramic tile glaze can therefore leach out over time (USEPA, 1998). It is therefore possible for lead, which is a human carcinogen, to be released to the interior of buildings through abrasion as the floor tiles wear out or are damaged over time HBN, 2015a). The US ceramic tile industry has largely responded to this solubility issue by eliminating most heavy metals – lead, cadmium and antimony – from use in glazes. To reduce the industry’s atmospheric emissions of lead; and also avoid/minimise user exposure to lead, the Italian ceramic tile sector switched to a single glazing system which enables the manufacturer to replace a substantial proportion of lead with boron as the active ingredient in the glaze (Nicoletti et al, 2002). This approach makes it possible to label ceramic tiles as “low-lead” products. However, the use of boron-based glazing results in substantial atmospheric

releases of arsenic, a classified PBT. Hence, the change in glazing technology may not necessarily have improved the toxicity profile of common ceramic floor/wall tiles. The purpose of the secondary glazing is to ward off fungal and bacterial attack of the tile surface. The antimicrobials most commonly used by the ceramic tile industry include IBPC (Horn et al, 2002); and Ag-NP or Ag+TiO2-NP (Sanchez et al). IBPC is a skin sensitizer and an aquatic toxicant (Allsop et al, 2005). Ag-NP has been shown to leach from products, wash down drains; and end up in water treatment facilities (Coffin, 2014). It is a potential human toxin and aquatic toxicant (EC, 2014). TiO2 was initially considered to be inert but has been re-classified by the IARC as possibly carcinogenic (CCOHS, 2014). Among others, TiO2-NP has been shown to induce genotoxicity and DNA damage in animals exposed to it (Trouiller et al, 2009). It would therefore be prudent to avoid or drastically limit human exposure to this chemical.

Constituent

Chemical of concern

Hazard

Chemical group

Clay, tile body

Fluorine

Aquatic and terrestrial toxicant

Halogen

Chlorine

Aquatic toxicant

Halogen

Primary glaze, lead-based

Lead

CMR

Heavy metal

Primary glaze, boron-based

Arsenic

CMR

Heavy metal

Secondary glaze, antimicrobial

Ag-NP

Potential human toxin Aquatic toxicant Table 8: Generic toxicity profile of ceramic floor/ wall tile

70

THE GREEN BUILDING HANDBOOK


3

MATERIALS EMBODIED TOXICITY

Constituent

Chemical of concern

Hazard

Chemical group

Fibre, synthetic

Furan

PBT/POP

SVOC

Xylene

ELoC

VOC

PAHs

Possibly CMR

SVOC

Fibre, plant fibre, pesticide

Bromoxynil

CMR

SVOC

Fibre, wool, antimicrobial

Permethrin

Possibly CMR

SVOC

Fibre, all, stain repellent,

EtFOSE/MeFOSE

PBT/POP

SVOC

Fibre, wool, dye

Chromium

PBT

Heavy metal

Backing, SBR

Toluene

Possibly CMR

VOC

Styrene

Possibly CMR

VOC

4-PCH

ELoC

SVOC

Backing, plant fibre, antimicrobial

Permethrin

Possibly CMR

SVOC

Backing, recycled tyre

Naphthalene

CMR

VOC

PAHs

PBT

SVOC

Lead

CMR

Heavy metal

Carbon nanoparticles

Possibly CMR

Arsenic

CMR

Heavy metal

Chromium

CMR

Heavy metal

Formaldehyde

CMR

VOC

Vinyl acetate

Possibly CMR

VOC

Ethyl hexanol

ELoC

VOC

Backing, fly ash

Backing, PVC

Table 9: Toxicity profiles of common carpet constituents

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71


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3 Carpet A typical carpet is composed of fibres on a primary backing which is bonded with adhesive to a secondary backing. Most carpet fibres are dyed and many are protected with a factory applied stain repellent. Synthetic carpet fibres include nylon, polyester, polyamide and polypropylene all of which are made from specific hydrocarbons that are refined from either crude oil or natural gas. Synthetic fibres have a common upstream burden of PBTs and other toxic chemicals used in the extraction and refining process of fossil fuels.

MATERIALS EMBODIED TOXICITY

Natural carpet fibres include animal fibres and plant fibres. Wool, which is naturally stain resistant, is the animal fibre most commonly used in the production of carpets. However, not even the life cycle of 100% wool carpet is toxin-free. Chromium, a CMR, is a key ingredient in common wool carpet dyes. Materials containing organic compounds might be damaged through attack by fungi, microbes or insects. Biocides are therefore widely applied by manufacturers to protect natural carpet fibres against such potential attacks (Horn et al, 2002). The biocide most commonly used to protect wool carpet

Constituent

Chemical of concern

Hazard category

Chemical group

PVC resin

Chlorine gas Ethylene oxide EDC Dioxin Mercury

Acute toxicity CMR Possibly CMR PBT/POP Possibly CMR

VOC VOC SVOC Heavy metal

Stabiliser

Cadmium Lead

CMR Possibly CMR

Heavy metal Heavy metal

Pigment

Carbon black Titanium dioxide

Possibly CMR Possibly CMR

Surface coating

Acetaldehyde Ethylbenzene

CMR CMR

VOC VOC

Plasticizer

BBzP DEHP DnHP

ELoC CMR Possibly CMR

SVOC SVOC SVOC

Flame retardant

PBDE

PBT, aquatic toxicant

SVOC

Deca-BDE

CMR, aquatic toxicant

SVOC

Table 10: Toxicity profile of PVC floor/wall covering ingredients

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73


MATERIALS EMBODIED TOXICITY

3

in this way is Permethrin. Similarly, plantbased carpet fibres are not toxin-free. Plant fibres are derived from industrial crops which are routinely sprayed with a range of toxic agro-chemicals during cultivation. For example, the pesticides approved for cultivation of flax in the USA are trifluran, mancozeb, bromoxynil and trichlorfon (Lent et al, 2010). Trifluran is a PBT. The remaining three chemicals are CMRs. Furthermore, the cultivation of industrial crops based on inorganic fertilisers invariably contributes to eco-toxicity due to emissions of the heavy metal content to the soil (Corbiere-Nicollier et al, 2001; van der Werf, 2004). Carpet backings are made from materials ranging from natural materials, such as jute, to 100% recycled content materials such as fly ash or recycled car tyres. The carpet backing-specific toxicity issues, which are not discussed in the above paragraphs, are highlighted in Table 9.

Poly vinyl chloride

The construction industry is responsible for more than 60% of worldwide PVC use of which a substantial proportion comprises floor coverings in the interior of buildings. PVC is a popular floor covering which is suitable for both residential and commercial buildings. It is usually manufactured in sheet or tile form. PVC wall coverings are commonly specified for hospitals and clinics. PVC floor/wall sheet is primarily composed of PVC resin, stabilisers, pigments, surface coatings, plasticisers and flame retardants. All stages of PVC life cycle, from cradleto-grave, raise human and environmental health concerns. The production of PVC resin results in the atmospheric release of HCB and a range of PCBs, all of which are on the Stockholm Convention’s list of POPs (Lent et al, 2010). The major stabilisers used in PVC sheet production include lead and cadmium both of which are listed as

74

THE GREEN BUILDING HANDBOOK

human carcinogens (CMRs) by the IARC. The pigments commonly used are carbon black and titanium dioxide – both have been identified as possible CMRs by the IARC. Research results indicate that PVC pigments could be inhaled as dust as a floor sheet wears out (Lent et al, 2010). The purpose of using plasticisers in the formulation of PVC is to impart flexibility. PVC sheeting can comprise up to 30% by weight of phthalate plasticisers such as DEHP and BBzP (Weschler and Nazaroff, 2008). Therefore twenty square metres of PVC floor covering could easily contain 20 kg of plasticiser. However, because plasticisers do not bond permanently with PVC, they can migrate to the surface of a product and into the surrounding environment – be it soil, waterways or body tissue (Qmed, 2014). Flame retardants are included in the formulation of PVC sheet products to ensure that the finished product meets fire regulations. However, recent research findings raise very high concerns about common PVC flame retardants. These flame retardants are implicated as significant manufacturing releases (Barber et al, 2005), found in household dust studies (CPA, 2005), found in human breast milk and other bodily fluids (EWG, 2003), and released in rivers, lakes and streams from where they could enter the food chain (Hoh et al, 2006).

Flooring installation products Ceramic tile installation products The installation of ceramic tiles requires mortars and grouts. Mortar is used to bond the back of tiles to the substrate. Grout is applied after tiles have been set in place, to fill the spaces between the tiles. Some products are formulated to serve a dual purpose as mortar/grout. Others are formulated to strictly function as a mortar


3

or a grout. Common mortars and grouts rely on a wide range of chemicals which may significantly influence the environmental and health profiles of the floor/wall coverings that they are used to install. Cement-based mortars Cement-based mortar is a specialised blend of Portland cement, filler, and a water retention agent, such as cellulose or glass fibre. The difference between a cementbased mortar and a polymer-modified cement-based mortar is that a polymer, such as styrene butadiene rubber (SBR), is added to the blend to increase bonding strength. The fillers used in cement-based mortars include quartz sand, blast furnace slag, fly ash and FGD gypsum. Quartz is listed as a human carcinogen by the IARC. Blast furnace slag, fly ash and FGD gypsum are industrial wastes – therefore the mortars that they are used to formulate are recycled content or “green” mortars. However, blast furnace slag as a possible carcinogen (USS, 2015). Fly ash can contain heavy metals such as mercury and arsenic. The IARC describes mercury is a possible carcinogen; and arsenic is listed by the WHO as a human carcinogen. Like fly ash, FGD contains heavy metals, especially mercury. The manufacturing phases of the other ingredients, such as Portland cement, glass fibre, cellulose derivatives and the SBR polymer are associated with CMRs and PBTs (HBN, 2015b). The toxicity profile for cementbased mortar is indicated in Table 11. 100% solid epoxy systems dry with a smooth surface, and are more resilient than their cement-based counterparts. Because of this, epoxy systems are generally used as grouts, but many epoxy grouts on the market can also be used as mortar (HBN). Like all epoxies, these systems rely on the standard 2-part epoxy reaction, requiring Bisphenol-A (BPA), epichlorohydrin, and

MATERIALS EMBODIED TOXICITY

various catalyzing amines. The fillers used in epoxy systems are quartz sand or glass. According to the IARC, BPA is not classifiable as to its carcinogenicity. However, the results of studies show that at the very least, BPA is a potential endocrine disruptor (CCS, 2015). Epichlorohydrin, which is primarily produced for use as an epoxy hardener, is listed by both the United States Environmental Protection Agency (USEPA) and the IACR as a probable carcinogen – it is also a potent eye and respiratory irritant. Epoxy and urethane grouts may use both post-industrial and post-consumer recycled glass as filler. Epoxy mortar/grout formulations may include antimicrobials and stain repellents. The toxicity profiles of the mortar/grout and additives are indicated in Tables 11 and 12 respectively. Epoxy mortar/grout (emulsion) Unlike 100% solid epoxies, epoxy emulsions blend the two-part epoxy formulation with Portland cement and sand, and function more as a polymer-modified cement-based mortar or grout than a true epoxy. Because epoxy emulsions are porous, they tend to absorb liquids and stains. Stain repellent and antimicrobial additives are therefore included in epoxy emulsion formulations. The toxicity profiles of epoxy mortar/grout and common additives are indicated in Tables 11 and 12 respectively. Urethane grout Urethane is the latest chemistry to be used in grouts. Unlike most cement-based and epoxy systems, urethane grouts come premixed. Product literature reveals very little about the specific urethane ingredients used. However, the technology behind the grout is likely to be similar to that of the urethane clear coat technology used on all cars today. The key ingredients are therefore likely to be acetaldehyde and ethylbenzene,

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75


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MATERIALS EMBODIED TOXICITY

Building product

Constituent material

Chemical of concern

Hazard class

Chemical group

Cement-based mortar / cement-based mortar with additive

Binder, Portland cement

Mercury Dioxin

Possible CMR CMR

N/A

Filler, quartz sand

Quartz

CMR

Filler, blast furnace slag

None

Possibly CMR

N/A

Filler, fly ash

Mercury Arsenic

Possibly CMR PBT

Heavy metal Heavy metal

Filler, synthetic gypsum

Mercury

Possibly CMR

Heavy metal

Epoxy grout / epoxy mortar (100% solid)

Epoxy grout / epoxy mortar (emulsion)

Water retention agent, cellulose

PBT

Water retention agent, glass fibre

PBT

Bonding additive, SBR

Styrene

Possibly CMR

VOC

Epoxy part A

BPA

Potential toxin

Residual

Epoxy part B

Epichlorohydrin Possibly CMR

Filler

Quartz

CMR

Epoxy part A

BPA

Potential toxin

Epoxy part B

Epichlorohydrin Possibly CMR

Residual

Binder, Portland cement

Mercury

Possibly CMR

Heavy metal

Filler, ordinary sand

None

N/A

Inert

Residual

Residual

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77


MATERIALS EMBODIED TOXICITY

Urethane (premixed grout)

3

Acetaldehyde

CMR

VOC

Ethylbenzene

CMR

VOC

Table 11: Toxicity profiles of common grouts and mortars

both of which are listed by several agencies for their cancer-causing potential. The antimicrobials most likely to be included in the formulation of urethane grouts are Diuron, a pesticide, or silver nanoparticles (Ag-NP). Diuron has been found to be acutely toxic in aquatic environments. Ag-NP is a confirmed aquatic toxicant (lethal). Human toxicity has not been negated or confirmed (EC, 2014). Moreover, there is evidence that Ag-NP can leach out of the product to which it is added. This means that the antimicrobial property of the grout will be lost with time. Because of the very small size of Ag-NP, and its ability to easily enter living cells, this tendency towards leaching may have grave consequences for human and environmental health (Coffin, 2014). The toxicity profiles of urethane mortar/grout and common additives are indicated in Tables 11 and 12 respectively.

Carpet and resilient flooring installation adhesives

Adhesives are used to bond floor coverings, through non-mechanical means, to the substrate. Floor coverings commonly installed with adhesives include carpet and resilient and wood floor coverings. Adhesives are generally composed of a binder, which is the primary ingredient, and a range of secondary ingredients (Ullman, 1985). The secondary ingredients may include plasticisers, fillers, thickeners, hardeners, non-reactive resins and setting retarders. Common binders in adhesives

78

THE GREEN BUILDING HANDBOOK

include acrylate polymers, epoxy, synthetic latex and polyurethane. There are four types of adhesive in general use – solution-based, solventless, reactive and pressure-sensitive (OECD, 2009). The adhesives most commonly used to install floor coverings are the solution-based and reactive types (HBN, 2015c). Adhesives described as solution-based may be waterbased or organic solvent-based systems. In response to environmental regulation, manufacturers have largely discontinued the production of organic solvent-based systems therefore contemporary markets rely mainly on the aqueous dispersions of acrylate polymer and synthetic latex. The most common reactive adhesive systems include single and two-part epoxy and polyurethane systems. In a review of carpet adhesive toxicity, HBN researchers found that carpet was almost always likely to be installed with water-based acrylic or latex adhesives. By contrast, resilient flooring was likely to be installed by any adhesive type including but not limited to acrylic, latex, epoxy and polyurethane. When the HBN researchers compared the solution-based to the reactive adhesive systems, the researchers concluded that the solution-based systems were a bit better than the reactive systems. This is because the reactive systems utilise more toxic content (HBN, 2015c). Table 13 indicates the toxicity profile of common non-VOC ingredients used in the formulation of different types of flooring adhesives.


3

Flooring adhesives are a significant VOC emission source – they may also play a central role in sick building syndrome (SBS) complaints, namely: • When Katsoyiannis et al (2008) used four types of emission chambers to compare PVC and carpet samples; they found that 4-PCH had a strong odour. As compared to other VOCs investigated in the study, the concentrations of 4-PCH were higher; and did not dissipate in a few hours. They concluded that the primary source of 4-PCH was the flooring adhesive. • In conclusion to an investigation on the source of VOC emissions to indoor air, Sjoberg et al (2009) found that 2E1H emissions, which were off-gassed from flooring adhesive, correlated well to SBS complaints.

MATERIALS EMBODIED TOXICITY

• Similarly, Chino et al (2012) concluded that 2E1H had a strong odour; and that the off-gassing of this chemical from the adhesives dominated overall VOC emissions rates from PVC and carpet flooring systems.

Summary of findings

This chapter has documented a broad array of hazardous chemicals which commonly occur in the building product life cycle. The human and environmental health consequences of exposure to these chemicals are of grave concern. The health hazards could manifest at any stage of the building product life cycle, from cradle-tograve. This chapter discusses the health risks arising from exposure under four headings, namely:

Additive category

Commonly used in

Additive name

Known or suspected human and environmental health hazard

Stain repellent

Grouts, mortars

D4

Very high concern, PBT / vPvB (HBN, 2015b)

Stain repellent

Grouts, mortars

EtFOSE/MeFOSE

PBT/POP

Antimicrobial

Grouts, mortars, adhesives

Ag-NP

Aquatic toxicant (lethal), potential human toxicity (EC, 2014)

Antimicrobial

Adhesives

Triclosan

CMR Aquatic toxicant

Surfactant

Adhesives

4-Nonylphenol

CMR Aquatic toxicant

Table 12: Toxicity profile of additives commonly included in grouts, mortars and adhesives

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3

• “Very high concern” persistent and bioaccumulative toxicants (PBTs); • “High concern” carcinogenic, mutagenic and reproductive (CMR) toxicants; • “Moderate concern” substances of equivalent level of concern (ELoC); and • Eco-toxicity. Exposure to PBTs is a major health risk for both humans and ecosystems. The CMR and ELoC categories are specific to human health. Eco-toxicity is concerned with the health of various aquatic and terrestrial ecosystems. The major groups of hazardous chemicals in the building product life cycle are volatile organic compounds, semi-volatile organic compounds and heavy metals. This chapter has focussed on VOCs and SVOCs both of which are more prevalent in the indoor environment than outdoors. The human health effects arising from exposure to VOCs can vary from sensory irritation, due to odour, or to toxic reactions, for example, cancer. The key strategies for reducing human exposure to VOCs in the indoor environment are increased ventilation; and substitution of standard Adhesive type

Constituent material

MATERIALS EMBODIED TOXICITY

building products with low emitting products. In addition to this, some countries are using VOC regulation to limit outdoor abundance of VOCs, reduce the role of VOCs in ground level ozone formation and thereby protect both human and environmental health. As compared to VOCs, exposure to SVOCs may represent a far higher level of risk for both human and ecosystem health. This is because the exposure pathways may make it extremely difficult to avoid contact once an SVOC is released into the environment. A large proportion of SVOCs is already classified as PBTs or ought to be classified as such. A significant number of SVOCs have been banned under The Stockholm Convention on persistent organic pollutants (POPs). Furthermore, many SVOCs that are used as additives to enhance the properties of common building products are now subject to restrictions and limits under the European chemical policy, REACH. The lessons learnt by identifying chemicals of concern in the building product life cycle; and linking them to health hazards, are applied in the case study to develop preliminary toxicity profiles for

Chemical of concern

Hazard class

Acrylic / latex Content (solution-based) Content Content

NP NPE Antimicrobial

Sensitizer Sensitizer CMR

Epoxy (reactive)

Epoxy part A Epoxy part B

BADGE CMR Epichlorohydrin Possibly CMR

Polyurethane (reactive)

Content Content

Diisocyanates (MDI) BADGE

Chemical group

VOC SVOC

ELoC CMR

Table 13: Toxicity profile of non-VOC ingredients commonly included in adhesives for wall /floor coverings

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major South African floor/wall covering products. Amongst others, the results of the case study suggest that: • None of the three major South African floor/wall covering products investigated in this study have a toxin-free profile. The choice of installation products – grouts, mortars, adhesives and their additives may exacerbate the toxic load. • Not even 100% renewable content floor coverings are hazard-free. This is because of the generally toxic nature of key manufacturing additives, such as stain repellents; and farming practices which rely on synthetic fertilisers. • The ‘green’ trend of selecting recycled content materials that incorporate waste from other industries – for example, fly ash, may save virgin raw materials and their embodied energy, but may exacerbate the problem of embodied toxicity.

Conclusion and future research

Awareness and management of chemical hazard in the building product life cycle is at least, in principle, now recognised as good practice. The main focus of current management strategies is one life stage – the use phase – one group of hazardous chemicals – VOCs – and one area of

protection – human health. However, toxicity can manifest at any stage of the building product life cycle. It could be attributed to exposure to non-VOCs, in particular, SVOCs. Furthermore, exposure to hazardous chemicals can have adverse effects on both human and ecosystem health. For ecosystems, the issues extend beyond well-being to survival – there is a risk of exponential failure of natural systems which could in turn jeopardise human health. Good practice should therefore shift towards a whole systems approach which can identify and address all human and environmental health hazards in a comprehensive manner. Such comprehensive frameworks for managing chemical hazards in the building product life cycle already exist in the European Union and in Japan. This chapter has been limited to a brief description of toxic chemicals in the life cycle of common building products. Major floor coverings and their installation products were included as a case study. A future chapter will explore the new approaches adopted or emerging within the European Union, Japan and elsewhere; and compare these to the South African status. New regulatory provisions and best practices that could fill the gap in the South African context will be identified and discussed.

References

• • • • •

Allsopp, M., Walters, A. and Santillo, D. 2005. Factsheets on uses and hazards of chemical ingredients of sanitized preparations (with particular reference to criteria for “substances of very high concern” under REACH) http://www.greenpeace.to/publications/sanitized_2005.pdf Athena SMI, 1998. Life cycle analysis of brick and mortar products. Available at calculatelca. com/wp.../LCA%20Reports/Brick_And_Mortar_Products.pdf AQS, 2010. Defining green products. http://www.cleanlink.com/pdf/casestudieswhitepapers/ Defining_Green_Products.pdf Barber, J., Sweetman, A. and Jones, K. 2005. HCB – sources, environmental fate and risk charac-


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• • • • • • • • • • • • • • • • • • • • • • • • • • • •

MATERIALS EMBODIED TOXICITY

terisation. CCOHS, 2014. Titanium Dioxide Classified as Possibly Carcinogenic to Humans http://www.ccohs.ca/headlines/text186.html ChemicalWatch, 2013. End in sight for flame retardant HBCD? http://chemicalwatch. com/16534/end-in-sight-fo Chino, S., Kato, S., Seo, J. and Kim, J. 2013. Measurement of 2-ethyl-1-hexanol emitted from flooring materials and adhesives. Journal of adhesion science and technology, 27(2013) Nos.56, 659-670 CHMPOPs, 2015. List of acceptable purposes and specific exemptions for production and use of PFOS, its salts. http://chmpops.int/implementation/NewsPOPs/The Coffin, M. 2014. One tiny problem with mortar and grout: nanosilver. https://www.pharosproject.net/blog/show/185/one-tiny-problem CIRS, 2015. PFOS/ PFOA Testing. http://www.cirs-reach.com/Testing/PFOS_PFOA_Testing.html Corbière-Nicollier, T., Gfeller Laban B., Lundquist, L., Leterrier, Y., Manson, J.A.E and Jolliet, O. 2000. Life cycle assessment of biofibres replacing glass fibres as reinforcement in plastics. Resources, Conservation and Recycling, 33 (2001) 267-287. CCS, 2015. Bisphenol A (BPA) http://www.cancer.ca/en/prevention-and-screening/be-aware/harmful-substances-and-environmental-risks/bpa/?region=bc CPA, 2005. Sick of Dust: Chemicals in Common Products - a Needless Health Risk in our Homes. http://www.cleanproduction.org/resources/entry/sick-of-dust EC, 2014. Opinion on Nano silver: safety, health and environmental effects and role in antimicrobial resistance. http://ec.europa.eu/health/scientific_committees/emerging/docs/ scenihr_o_039.pdf ECHA, 2015a. Why are chemicals important? http://echa.europa.eu/chemicals-in-our-life/why-are-chemicals-important ECHA, 2015b. Persisitent and bioaccumulative substances. http://echa.europa.eu/chemicals-in-our-life/which-chemicals-are-of-concern/svhc ECHA, 2015c. Carcinogens, mutagens and/or reproductive toxicants. http://echa.europa.eu/ chemicals-in-our-life/which-chemicals-are-of-concern/svhc ECHA, 2015d. Chemicals of equivalent level of concern. http://echa.europa.eu/chemicals-in-our-life/which-chemicals-are-of-concern/svhc EWG, 2003. Mother’s Milk: Toxic Fire Retardants (PBDEs) in Human Breast Milk. http://www.ewg. org/research/mothers-milk-0 Gilder A. and Govender, V. 2014. Regulations on the phasing out of the use of polychlorinated biphenyl materials and polychlorinated biphenyl contaminated materials https://www.ensafrica.com/news/regulations-on-the-phasing-out-of-the-use-of-polychlorinated-biphenyls-material?Id=1502&STitle=environmental%20ENSight Guinee, J.B. (ed) 2002. Handbook on life cycle assessment – operational guide to the ISO standards. Dordrecht: Kluwer Academic Publishers. HBN, 2015a. Pharos Building Product Library: ceramic tile category description. https://pharosproject.net/category/show/111 HBN, 2015b. Pharos Building Product Library: tile installation products http://api.pharosproject. net/product_category/show/id/116 HBN, 2015c. Pharos Building Product Library: adhesives category description https://www. pharosproject.net/category/show/9 Hoh, E., Zhu, L. and Hites, R. 2006. Dechlorane plus, a chlorinated flame retardant in the Great Lakes. Environmental Science and Technology 2006, 40(4), pp. 1184-1189. Horn, W., Jann, O., Burbiel, M. and Kalus.2002. Biocide emissions from materials into indoor air. In proceedings – Indoor Air 2002. http://www.irbnet.de/daten/iconda/CIB6909.pdf

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• • • • •

• • • • • • • • • • • • • • • • • •

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Jȁrup, L. 2003. Hazards of heavy metal contamination. http://bmb.oxfordjournals.org/content/68/1/167.full Jönsson, A. 2000. Is it feasible to address indoor climate issues in LCA? Environmental Impact Assessment Review 20(2000) 241-259. Katsoyiannis, A., Leva, P. and Kotzias, D. 2008. VOC and carbonyl emissions from carpets: a comparative study using four types of environmental chambers. Journal of Hazardous Materials, 152 (2008) 669-676 Lent, T., Silas J. and Vallette J. 2009. Resilient flooring and chemical hazards – a comparative analysis of vinyl and other alternatives for health care. http://healthybuilding.net/uploads/ files/resilient-flooring-chemical-hazards-a-comparative-analysis-of-vinyl-and-other-alternatives-for-health-care.pdf Levin, H. 2010. National programmes to assess IEQ effects of building materials and products. http://www.epa.gov/iaq/pdfs/hal_levin_paper.pdf Liddell, H., Gilbert, J. and Halliday, S. 2008. Design and detailing for toxic chemical reduction in buildings. http://www.seda.uk.net/assets/files/guides/dfcrb.pdf Lott, S. and Vallette, J. 2013. Full disclosure required: a strategy to prevent asthma through building product selection. www.healthybuilding.net/.../asthmagens/HBN_Report_Full_Disclosure Nicoletti, G.M., Notarnicola, B. and Tassielli, G. 2002. Comparative life cycle assessment of flooring materials: ceramic versus marble tiles. Journal of Cleaner Production 10(2002) 283-296 OECD, 2009. Emissions scenario document on adhesive formulations. http://oecd.org/env/ehs/ risk-assessment/emissionscenariodocuments.htm QMED, 2014. The long goodbye to DEHP-plasticised PVC. http://www.qmed.com/mpmn/medtechpulse/long-goodbye-dehp-plast.. Sanchez, Mu-oz, Marinova, Dela Fuente, Nunez, Rodriguez, Sanz and Carda. Research and development for ceramic tiles in the 21st Century: competition, diversity and functionality. Tile Today # 74. http://www.infotile.com/publications Sjöberg, A., Blondeau, P. and Johansson, P. 2010. Measurement methods for stored VOC in concrete floors. http://www.concrete.org/publications/internationalconcreteabstractsportal/m/ details/i/51686697.aspx SSS Europe 2015. REACH Annex XVII, September 2012, entry 53. http://ssseurope.org/REACH_ Restriction_List_September_2012.pdf Tikul, N. and Srichandr, P. 2010. Assessing the environmental impact of ceramic tile production in Thailand. Journal of the Ceramic Society of Japan, pp 887- 894 USS, 2015. Basic blast furnace slag safety data sheet. https://www.ussteel.com/.../Basic+Blast+Furnace+Slag+SDS+(7631)+7-10... USEPA, 2015. Ground level ozone makes it harder to breathe. http://www.epa.gov/groundlevelozone/ USEPA, 1998. Office of Air Quality Planning and Standards - Locating and Estimating Emissions from Sources of Lead and Lead Compounds. Ullmann, F., Gerhartz, W., Yamamoto, Y.S., Campbell, F.T., Pfefferkorn, R. and Rounsaville, J.F. 1988. Ullmann’s Encyclopaedia of industrial chemistry. 5th Ed. Vol. A1, Abrasives to aluminium oxides. VCH, 1988. Van der Werf, H.M.G. 2004. Life cycle assessment of field production of fibre hemp, the effect of production practices on environmental impacts. Euphytica 140 (2004) 13-23. Weschler, C.J. and Nazaroff, W.W. 2008. Semivolatile organic compounds in indoor environments. Atmospheric Environment 42 (2008) 9018-9040. WWF, 2013. Chemical check-up: An analysis of chemicals in the blood of Members of the European Parliament. www.panda.org/downloads/europe/checkupmain.pdf

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Appendix A 4-PCH 4-Phenylcyclohexene Ag-NP Silver nanoparticle BADGE Bisphenol A di-glycidyl ether BBzP Butylbenzyl phthalate DEHP Di-ethylhexyl phthalate DDT Dichloro diphenyl trichloroethane D4 Octamethyl cyclotetra siloxane Deca-BDE Decabromo diphenyl ether DnHP Di-n-hexyl phthalate EDC Ethylene di-chloride EtFOSE N-ethyl perfluorooctane sufonamidoethanol HCB Hexachlorobenzene HBCD, HBCDD Hexabromocyclododecane MA Maleic anhydride/ acid anhydride MeFOSE N-methyl perfluorooctane sufonamidoethanol MMA Methyl methacrylate MDI Methylene diphenyl diisocyanate PAN Phthalic anhydride PAHs Polycyclic aromatic hydrocarbons PBB Polybrominated biphenyl PBDE Polybrominated diphenyl ethers PCBs Polychlorinated biphenyls Penta-BDE Pentabromodiphenyl ether PFOS Perfluorooctane sulfonate PMMA Poly-methyl methacrylate TCPP Tris (chloropropyl) phosphate TDI Toluene diisocyanate TiO2-NP Titanium dioxide nanoparticles Tris-BP Tris dibromopropyl phosphate

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PROFILE

AQUATRIP SAVES DOUGLAS MBOPA R360000 IN ONE YEAR Douglas Mbopa Secondary School in Motherwell PE last year was accumulating between R30-R60K a month in water and sanitation accounts and in a 19 month period had paid over R2.8m in W&S accounts to the metro. AquaTrip was invited by Shannon Barkes from W&S Nelson Mandela Bay Metro to pilot our systems in September 2013. The AquaTrip has now been installed for 1 year and the results speak for themselves. The AquaTrip has reduced the schools monthly water consumption from 2244Kl to R476Kl per month that means each year this school will only pay R70K- R90K in water and sewerage and will keep the water utility well within the school’s budget of R120K per annum. School’s typical of Douglas Mbopa all suffer the same fate, failing infrastructure as a result of the old regime using sub- standard building material

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resulting in plumbing failure which leads to Loss of Water and Money. Total consumption at the school for the year was 5723KL which was close on what the school was using some months prior to AquaTrip been installed. For the duration of the year, the monthly W&S account was less than R10K a month, that’s an 85% water saving month on month.

HOW THE AQUATRIP WORKS The AquaTrip is a Permanently Installed standalone Leak Detection System. The Aquatrip monitors the flow of water into a property and in the event of a burst geyser, pipes, taps left running, dripping toilet cisterns, urinal’s and vandalism the Aquatrip will automatically switch off the water. The AquaTrip is installed onto the incoming water inlet of the ablution


PROFILE

facilities, this is where high water consumption takes place which makes it prone to leaks, negligence and vandalism, the AquaTrip is set to 2 minute trip time- which means when someone enters the facility and leaves the tap running, or toilet cistern running etc.; the Aquatrip will automatically switch off the water. So while the facility is unoccupied water and money is being saved, and then when someone enters the facility again the motion sensors hidden on the ceiling will automatically reinstate the water so the patron can use the facility. We also put a AquaTrip on the main incoming line to the premises, and programme the AquaTrip to go into a sleep mode during the schools operating hours, and then in the evening after closing time if any water flows for longer than 1 minute the AquaTrip shuts the water off until a preprogrammed time in the morning e.g.; 6am. This way the AquaTrip is able to eliminate night flow all together, eliminating any chance of burst pipes, running cisterns, urinals or taps left running. New and Existing Homes AquaTrip can be hard wired into a new building on construction

or seamlessly added to any existing building as a aftermarket installation raising its sustainability rating. Holiday Homes AquaTrip will monitor and safeguard the water supply during periods of extended absence. Unoccupied Buildings are at high risk from burst pipes or leaks which can go undetected for long periods of time causing large scale, costly damage. Rental Properties AquaTrip assists careless tenants to be more water wise and reduces the likelihood of taps left running or negligent water wastage. Commercial Buildings, Industrial Units and Offices Leaking toilet cisterns, urinals and taps left running are major causes water wastage in large office buildings. AquaTrip can be programmed to detect leaks and wastage in areas of high water usage, without inconveniencing users or interfering with normal water usage. Schools, Universities, Public Buildings and Institutions. Buildings with high levels of public use are often areas of major water wastage and consumption, often through lack of awareness, neglect or vandalism. AquaTrip will detect leaks and alert maintenance staff who can act to repair the leaks as they appear. When you consider all the pipes, taps, fittings and appliances in the community, the real extent of water lost and damage caused by known and unknown leaks and wastage, is measured in billions of litres and hundreds of millions of rands. Tons of CO2 emissions can be saved by reducing the energy required to purify and pump water, which is lost to leaks and wastage. AquaTrip is quality build to last and is fully SABS Approved

TO ORDER CONTACT Chris 0827168020 www.aquatrip.com chris@aquatrip.com

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The Smart Roof People In the fast moving, competitive world of construction, you only have one chance to get it right. So it’s a smart idea to choose quality products that won’t let you down. With over 50 years of technical know-how and practical experience, GRS is one of the largest manufacturers of quality metal roofing products in southern Africa, exporting to over 20 countries worldwide. State-of-the-art machinery and stringent quality checks ensure a superior product manufactured for ease of installation and a perfect fit. Through ongoing research and testing, GRS continually develops groundbreaking improvements. Our ingenious Klip-Lok and Klip-Tite systems have introduced transverse stiffeners (a first in South Africa) designed to achieve a more balanced system and a significantly higher wind uplift resistance. It’s smart. Really smart. SUPPLIERS OF CONCEALED FIX, PIERCED FIX, DECKING SYSTEMS, GRIT COATED METAL TILES AND VENTILATION SOLUTIONS So when you’re looking for roofing solutions, get smart with GRS. The smart roof people. Talk to us, The Smart Roof People on 011 898 2900 or visit www.globalroofs.co.za or email info@globalroofs.co.za

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THE LINK BETWEEN ENERGY AND WATER Water requirements for generating electricity

Wim Jonker-Klunne


THE ENERGY-WATER NEXUS

4

T

here is a direct, but often overlooked, link between electricity consumption and water usage: most electricity generation technologies do require water in their operations. The other way around this linkage is there as well: to get potable quality of water to consumers’ energy is required for purification and transportation. After disposing of used water, energy is required again for transportation and cleaning. This chapter will look at the energy and water nexus and concentrate on water requirements for electricity production.

Defining water usage

Water usage of electricity generation can be divided into water withdrawal and water consumption. The US Geological Service (Kenny, Barber, Hutson, Linsey, Lovelace, and Maupin, 2009) defines “withdrawal” as the amount of water removed from the ground or diverted from a water source for use, while “consumption” is the amount of water that is evaporated, transpired,

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incorporated into products or crops, or otherwise removed from the immediate water environment. This water usage can further be divided into the usage during construction or production and the usage during operation of the equipment. During operation water is being used in the electricity production processes, cleaning, cooling and other process related activities (e.g. scrubbing of exhaust gasses). Traditional, mostly fossil fuel based, electricity generation technologies see the bulk of the water usage during the operational phase of the equipment. Non-thermal renewable energy technologies however do not require vast amounts of water in the electricity generation phase and might therefore have most of the water requirements in the equipment production phase. As data on water consumption during manufacturing, as well as water use in the fuel cycle for preparation of the fuel (e.g. washing of coal at the mine), is scarce, very


electricity, cooling, sluicing of ash, ash handling and

water”.163

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THE ENERGY-WATER NEXUS

Figure 1: Water use during the coal combustion process at a power station

The cooling process All coal-fired power stations need a cooling process for power generation machinery as components can be damaged by extreme heat.164 Water is used to condense and cool steam165 - the cooling is necessary to condense the steam after it has passed through the turbine, and to eject the excess heat into the environment. Cooling can be achieved using water, air or a combination of the two.166 So-called ‘direct dry cooling’ technology keeps the cooling water in a separate closed circuit, which means that cooling happens through heat transfer rather than evaporation.167 Ironically, dry cooling does reduce water use, but is a less energy-efficient solution, and is also more expensive. Four coal-fired power stations currently use dry-cooling technology in South Africa168 and both Medupi and Kusile will use this technology.169

subjective to definitions of boundaries and very site-specific, the current article looks at water usage during the operational phase only.

Where is water required?

Electricity generating technologies use water for different processes, depending on their configuration. Thermal electricity generation technologies (e.g. coal, nuclear, and natural gas technologies, as well as Concentrated Solar Power – CSP - and biomass) generally require Water hungry coal: Burning South Africa’s water to produce electricity 14 water as the working fluid (and as the cooling medium to condense steam) as part of the Rankine cycle, the thermodynamic process that drives the steam engine. CSP facilities use water for steam cycle processes, for cleaning mirrors or heliostats, and for cooling if a cooling tower is used. Renewable energy technologies like solar PV systems require occasional panel washing, while wind power systems typically require no water at all (Macknick, Newmark, Heath, and Hallett, 2011).

Fossil fuel based power

Fossil fuel based power stations use a thermal process to convert the energy of the energy carrier into electricity. Fossil

Figure 1 Water use during the coal combustion process at acontrol power station (Greenpeace Africa) Air pollution measures Because burning coal to produce electricity is one of the most polluting practices on the planet, pollution control measures are required. Substantial amounts of water are needed for these processes: to handle and control the ash (a by-product of combustion), scrub out the sulphur released in the flue gas, and also for CCS - should this technology ever become available.

fuel based power stations burn their fuel to produce either hot air or steam to turn the turbines so that they are able to generate electricity. Three fifths of the heat released from the fuel combustion is lost as waste heat. Removal of this waste heat through cooling consumes enormous quantities of water. Water is used in the following processes in coal-fired power stations: water purification, the steam cycle in generating electricity, cooling, sluicing of ash, ash handling and disposal, drainage, sewage treatment and mine water recovery. Water is also used in certain air pollution control measures, and is discharged into ash slurry dams, which contain coal ash. However, the majority of water is used in just two processes: the internal steam cycle and the cooling process. Figure 1 illustrates how water is used during the combustion of coal to produce electricity. The process occurs as follows: demineralised water is piped above a boiler (2) where the coal is burnt, and the heat turns the water to steam. The steam then drives a turbine (3) to generate electricity (4). As the steam passes through the turbine it is fed into a condenser (6) and cooling tower (7), which transform the steam back into water (Wassung 2010).

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African Water Controls cc is the authorised distributor of Neoperl’s range of pressurecompensating regulated valves. We have been in this industry for over 30 years and have the 50 years experience of Neoperl’s scientists to rely on, should your situation require it. Pressure-compensated regulators, unlike their restrictor cousins, are a sophisticated technology that can compensate for varying pressures, while always allowing the prescribed quantity of water to flow, and they help to balance the pressure in the rest of the water network. These regulators allow us to manipulate the flow of water in any outlet or inline. We can therefore accurately predict water usage and from this, calculate the money saved in terms of water and energy consumption. The applications for these products range from a domestic shower environment to multi-story hotels that have to employ expensive mechanisms to ensure that higher floors have sufficient water. Because we can accurately predict the quantity of water required , quantity surveyors can accurately calculate the correct sizes of geysers, pumps and piping which in turn reduces costs. Contact us for further information: Tel: 011 331 9425 Fax: 086 770 5345 eMail: contact@africanwater.co.za


4

Recent developments in the design of thermal power plants, where the traditional cooling using cooling towers has been replaced with dry-cooling, did see a serious reduction in the water requirements. In general it can be said that the cooling system employed is often a greater determinant of water usage than the particular technology generating electricity, both in terms of water consumption and water withdrawal. Once-through cooling technologies withdraw 10 to 100 times more water per unit of electric generation than cooling tower technologies; yet cooling tower technologies consume at least twice as much water as once-through cooling technologies. Water consumption for dry cooling at CSP, biopower, and natural gas combined cycle plants is an order of magnitude less than for recirculating cooling at each of those types of plants (Macknick et al, 2011).

THE ENERGY-WATER NEXUS

Renewable energy technologies

Several studies have been conducted to quantitatively assess the water intensity of different electricity production technologies. Although there substantial differences between the approaches of these studies and their respective outcomes, there is almost unequivocal agreement that wind and solar PV use practically no water to operate and have minimum life-cycle water usage, and hence could offset negative water consumption trends (IRENA 2015). Figure 2 provides a summary of a review study on water intensity to demonstrate the standing of different energy-producing technologies as well as the variations for different cooling technologies which can dramatically change the water consumption and withdrawal factors

Figure 2 Water withdrawal and consumption per technology (Meldrum et al, 2013)

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THE ENERGY-WATER NEXUS

Figure 2.13 Global water use in the energy sector for different IEA scenarios, 2010, 2020 and 2035

billion cubic metre

800

600 400

200

2020

2010

Withdrawals: Source: IEA, 2012

Current Policies

New Policies Scenario

2035

450 Scenario

Consumption

Figure 3 Global water use in the energy sector for different IEA scenarios, The GCC region is looking to develop its vast 2010, 2020 and 2035 (IEA 2012)

owing in part to a marked shift in the power sector away from coal-fired plants towards renewables.

Regional-level projections also showcase a positive

renewable energy potential given the economic rationale in domestic hydrocarbon savings and associated opportunity costs that come with the overall water requirements ofcountry the electricity diversification of the energy mix. Each has announced a renewable energy plan - Bahraintrend. (5% generation mix show a declining As by 2020), Kuwait (10% by Oman (10% more technologies are2030), deployed that by require 2020), Qatar (2% by 2020), Saudi Arabia (54GW less water per unit of electricity produced by 2032), United Arab Emirates (7% by 2020 in the average water usage is reduced as well. Abu Dhabi and 5% by 2030 in Dubai), all of them Global projections assess in capacity terms except for Qatarthat (MoFA, IRENA the impacts of expanding renewables and REN21, 2013). These plans primarily focus on on solar energy. water use in the energy sector find that

impact ofNettles-Anderson, increased renewables Heath deployment (Meldrum, and on water2013). resources. In therenewable European Union, for Macknick, Some energy example, the – European Energy Association technologies such Wind as geothermal and wind energy avoided and the CSP(EWEA) – use estimates thermalthat power generation use of 387 billion litres of water in 2012 - equivalent could require substantial amounts of water to the average annual household water use of 3 during operation. For geothermal, water use million average EU households (EWEA, 2014). estimates vary widely depending on the The GCC region has among the world’s lowest technology and whether water required for renewable water resources, andor thedrawn demandfrom for cooling is sourced externally a renewables-dominated energy system Realising the renewable energy plans for the GCC water is expected fluids. to increase fivefold by 2050. onsite geothermal will be less water intensive compared to a could result in an estimated overall reduction of Extraction of fossil fuels and cooling during power CSP is found to be water intensive 20% business-as-usual expansion. For instance, and 22% in water withdrawal and consumption, generation requires withdrawal and consumption 8 (see figure 2.14). the power sector during the operations stage, particularly respectively, under all in three of the International Energy of water. As treated water is needed for extraction, is equivalent to an annual reduction of 18scenarios trillion where steam turbines are the prime This Agency (IEA)’s energy sector this results in a demand for desalination and litres of water withdrawn and 220 billion litres of mover, and water consumption levels water (IEA consumed. 2012) – the Current Policies Scenario, associated risks. Analysis shows that most of this are comparable to conventional thermal the New Policies Scenario and the 450 Figure 2.14 Potential for reduction in water withdrawals for power generation in GCC region by 2030 Scenario – water consumption will power plants. increase between 2010 and 2035 (see For hydropower, Saudi Arabia the main contributor to water usage is the evaporation from the Figure 3). Meanwhile, withdrawals will be Kuwait water reservoir. An issue of discussion in this more variable depending on trends related regard is howQatar much of the evaporation can to energy 20% demand, power generation reduction be attributed Oman to the generation of electricity mix, cooling technologies used and rate in water withdrawals and how much to other uses like water for of biofuels growth. The expanded role of Bahrain in 2030 irrigation.United Small run-of-river hydropower renewables in the New Policies Scenario Arab Emirates plants that do not have storage reservoirs – in which wind generation is 25% higher 30% 0% 5% 10% 15% 20% 25% do not encounter evaporation and are and solar PV is 60% higher in 2035 than in Percentage of total water used for generation Source: IRENA analysis considered to have zero water requirements the Current Policies Scenario – contributes The analysis considers water consumption for power generation in all GCC countries and includes water use during fuel extraction only for their operations. to (Saudi reducing for those countries using high shares of domestic oil resources for generation Arabia, Kuwaitwater and Oman). withdrawals. Water consumption fac- The tors for different technologies are derived primarily from NREL (2011), using median values. Total water use does not consider the sources 450 Scenario could be even less water of water due to lack of available data. The analysis does not account for financial considerations. Global trends intensive, owing in part to a marked shift IRENA With renewable energy technologies in the power sector away from coal-fired advancing on a world-wide scale, the plants towards renewables. 8

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The South African situation

4

The main electricity supplier in South Africa is state-owned utility Eskom. Currently the generation mix of Eskom is heavily skewed towards coal based power. With the promulgation of the Integrated Resource Plan 2010 (IRP 2010) this will change with a substantial amount of renewable energy based generation planned for the next 20 years. Figure 4 gives an indication of the development of the energy mix in South Africa. Based on Eskom’s data, currently Eskom uses approx. 1.35 litres of fresh water to produce 1 kWh of electricity (ESKOM 2011). This figure represents the water used by Eskom in the generation process and does exclude water usage during the extraction and processing the coal Eskom procures from coal mining companies. Based on improvements in technologies applied, the larger uptake of dry cooling and the introduction of renewable energy, Eskom is

expecting this figure to drop over time (see Figure 5). Very few independent studies have been done on the water consumption of the electricity sector in South Africa. With very little data available on local renewable energy generation technologies due to the incumbent nature of the sector, most analysis has been focused on the current coal fleet. Sparks et all (Sparks, Madhlopa, Keen, et al 2014) came to the data as given in Figure 6, while Greenpeace did produce an earlier study with the telling title of “Water Hungry Coal, Burning South Africa’s water to produce electricity” (Greenpeace Africa 2012). Both studies expect the water intensity of the electricity generation to come down with the introduction of renewable energy generation technologies. On top of this Greenpeace appeals to aggressive pursuing energy efficiency measures to reduce the demand for energy and with that the total amount of water required to service the electricity demand.

Figure 4 Expected developments in the energy mix of South Africa (DoE 2013)

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THE GREEN BUILDING HANDBOOK


4

a reduction of approximately 26%. Should these measures prove

seeks t

effective, instead of requiring 530bn litres of water to generate

out a

electricity in 2030, it is projected 270bn litres willNEXUS be THEthat ENERGY-WATER

these a

required.

and ag

Figure14: Eskom annual water usage in coal power plants

CO2 a

During Litres of water per year (bn) 600

produc

1.351kWh

domina

0.88kWh +205

fleet. Th

-262

resourc

450

better

genera 300

the 20

327

dioxide

270

electric

150

sector

as estim

Eskom’

0 2011

Figure 5 Water use by Eskom (ESKOM 2011)

Improvements Demand through growth efficiency (business-asusual scenario)

and de

2030

emitter When

Note: Figures relate to financial years. Source: Eskom.

becom

presen

on coa

significa

Figure 6 Water use for energy production in South Africa (Sparks et al, 2014)

References • • • • • • • • • •

Kenny JF, Barber NL, Hutson SS, Linsey KS, Lovelace JK, Maupin MA. Estimated use of water in the United States in 2005. 2009;Circular 1344. Macknick J, Newmark R, Heath G, Hallett KC. A review of operational water consumption and withdrawal factors for electricity generating technologies. 2011;NREL/TP-6A20-50900. 44 Eskom Holdings Limited The Eskom Factor 2011 Wassung N. Water scarcity and electricity generation in South Africa. [MPhil]. University of Stellenbosch; 2010. Greenpeace Africa. Water hungry coal - burning South Africa’s water to produce electricity. 2012. IRENA. Renewable energy in the water, energy & food nexus. 2015. J Meldrum, S Nettles-Anderson, G Heath and J.Macknick. Life cycle water use for electricity generation: A review and harmonization of literature estimates. Environmental Research Letters. 2013;8(1):015031. http://stacks.iop.org/1748-9326/8/i=1/a=015031. IEA. World energy outlook 2012. Paris: IEA; 2012. DoE. Integrated resource plan for electricity (IRP) 2010-2030 - update report 2013. 2013. ESKOM. The Eskom factor. 2011. Sparks D, Madhlopa A, Keen S, et al. Renewable energy choices and their water requirements in South Africa. Journal of Energy in Southern Africa. 2014;25(4):80--92.

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PROFILE

About 77% of South Africa’s electricity is derived directly from the firing of coal which, unfortunately, also leads to the production of highly toxic combustion wastes which have a very negative impact on both the environment and human health. Coal is also a finite resource and this is another reason why South Africa is moving to generating electricity using green energy technologies. The future is undoubtedly in generating clean and safe electricity. The country is entering a new era of electrical capacity growth, in which renewable technologies will feature strongly. To HellermannTyton, a global leader in the field of providing products and solutions that add value to electrical networks, providing renewable energy solutions is not a new challenge. With world-class sales, product development and manufacturing operations in thirty six countries worldwide, our businesses can offer cost-effective, high quality solutions for a wide range of applications, including wind and solar energy technologies. As the group strives to achieve its mission of being the “customer’s partner of choice”, so too is the South African operation, with an offering of over 6 000 products that cover every facet of identifying, routing, protecting, securing, connecting, terminating and testing of electrical networks. To enhance this offering to the local industry, we have added a number of products to our already comprehensive product portfolio, aimed at meeting the requirements of renewable energy installations. Of great importance in this new product line-up is our alliance with Hensel Electric. Not only has Hensel supplied into the renewable energy industry for many decades, but they are also a leader in cable junction boxes and

combinable enclosure systems. For renewable energy applications, HellermannTyton offers the ENYSUN product solution from Hensel. This product range is a world class locally assembled combiner box that complies with the new IEC 60 364-7-712 standard. It also provides a number of advantages when selecting and installing photovoltaic systems for on grid and off grid systems up to 1000VDC. The pre-fabricated PV string combiner boxes and control circuits are designed as per the customer’s specifications to perfectly fit each application. With regard to harsh environments, the ENYSUN enclosures are manufactured using very high quality Polycarbonate material offering a class II total insulation, impact resistance and IP65 ingress protection, UV resistance and also resistance to rain, ice and snow. Apart from the PV string combiner units, HellermannTyton also offers the following components for photovoltaic (PV) systems: PV and branch cable connectors; PV cable; Weather stabilised PV edge clips for fast and effective PV cable securing; Weather stabilised cable ties; All PV system labelling requirements, PV cable stripping and crimping tools; PV test instrumentation; Electronic string controllers to improve renewable energy data management technology with intelligent acquisition; calculation; recording and transmission of data. HellermannTyton South Africa is thus able to provide a high percentage of “local content” in its various locally designed, configured and pre-populated PV combiner boxes. This is all supported by trained sales and technical staff based at our four well established branches, strategically located throughout South Africa and a fully active Exports division servicing the Sub-Saharan Africa region. THE GREEN BUILDING HANDBOOK

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AN INTRODUCTION TO THE APPLICATION OF DEGREE-DAYS FOR BUILDING ENERGY EVALUATION

Tobias van Reenen (CSIR, Built Environment)


DEGREE-DAYS

5

Background and context

The estimation of a designed building’s energy consumption is best achieved through detailed building modelling and simulation. These simulation techniques can be prohibitively time consuming and expensive and the results are often no better than the degree of skill and data available. The application of a degree-days analysis offers an alternate and simplified method for assessing the relative impact of major design decisions for heating or cooling demand control within various climates. The degree-days index originated for the assessment of crop growing conditions and was used for that purpose well before its implementation as an indicator of building energy demand (Day, 2006; Strachey, 1878). Degree days serve as a good comparator of building heating or cooling demand within a defined climatic location and period. The higher the calculated index, the greater the energy demand. The index is generally expressed as either heating or cooling degree days separately (HDD or CDD). The following formula describes the association between degree days (heating) and building heating energy. Building Heating Energy (kW.h)= Overall Heat Loss/gain Coefficient (kW.K-1)×HDD (K.days)×24 (h.day-1) The formula can similarly be expressed for cooling energy. It can be seen from this that the correlation between the building energy demand and the HDD (and CDD) depends on the overall heat loss (or gain) coefficients. This in turn is unique to the building under consideration and thereby highlights the index’s usefulness as a comparative tool both for similar buildings between different climates and between the impacts of design decisions on the performance of a single building within a considered climate.

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Definition

Degree days can be defined as the time integral of the outdoor air temperature above a particular base temperature (units: K.day) (Strachey 1878). This essentially means that degrees days are the summation of differential between the outdoor temperature and the considered base temperature over time. The heating and cooling base temperatures mentioned above are the outdoor balance temperatures at which a considered building would not need either heating or cooling respectively. Depending on the comfort model followed and the specific building under consideration, the heating and cooling base temperatures may differ from each other.

Calculation

The most precise way of calculating degree days is also the simplest, assuming that hourly temperature data (or better) is available. The index is simply the sum of the hourly difference between the outdoor temperature and an appropriate base temperature. For cooling, only the positive values are included and for heating only the numerical absolutes of the negative values are summed. Both heating and cooling degree day indices are reported as a positive total after dividing the hourly totals by 24 (hours). Where hourly temperature data is not available or the computing capability is (or historically was) unavailable, degree days are estimated from daily, monthly, seasonal or annual temperature averages and daily variations. It is self-evident that estimations based on greater time period averages yield progressively less accurate results. Where mean monthly or daily data is used to estimate degree days, factors for local climatic variability need to be incorporated in the estimation. Currently, hourly based degree-day data is not freely available for South Africa. In


5

DEGREE-DAYS

Degree Days  with     18◦C  Base  Temperature     HDD  |  CDD  

30 25   20   15  

Indoor Temp   Average   Outdoor   Temp  

10 5   0  

Figure 1: Illustrative example of hourly degree variations showing base temperature, indoor and average temperatures.

addition, the impact of global warming in decreasing heating and increasing cooling energy demands requires that degree-day data reflects the future climate in which today’s new buildings will be operating. A conundrum exists in that available weather data sets are based on an average of the previous 20-30 years and reflect climates of over a decade past (Day, 2006). The author suggests that degree-day data created from both historical data and predicted temperature trends should be published with some urgency. The challenge with this requirement remains the generation of valid climatic data to a sufficient spatial and temporal resolution (hourly data is needed at better than a 50km grid resolution)

Selection of base temperature

The selected base temperature accounts for the minimum difference between

actual outdoor and the mean indoor comfort temperatures. The selection of base temperature should also reflect the expected building internal operational heat loads. The base temperature assumes a building in a simplified condition of thermal equilibrium. Heating and cooling base temperatures can also be selected to reflect seasonal adaptation and perceptions of comfort by adjusting the required mean indoor comfort temperature up in summer (26 °C) and down in winter (19 °C). Internal building heat loads and heat loss coefficients could differ significantly between building types, resulting in distinct base temperatures and building responses to variations of climate.

Correlation between HDD/ CDD and building energy

A good correlation exists between degree days and building heating or cooling demand. The calculation of heating degree

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DEGREE-DAYS

5

days approximates a simplistic heating demand calculation and therefore offers a better correlation to the relative building energy demand than cooling degree days. This disparity in degree of correlation is evident as the CDD index is calculated from dry bulb temperatures only and does not readily represent the latent heat portion of the building’s cooling demand. To correct for this, CDD base temperature can be adjusted down to represent the equivalent sensible cooling demand. This adjustment needs to take cognisance of the fact that an adjustment in base temperature does not result in a linear change in the degree day total. This is because the daily temperature variation is not linear. In addition, it is important to remember the relationship between a building’s heating or cooling demand and the local degree day index is unique to that building. A different association would exist for a building of differing construction and occupancy type as different buildings have distinct heat loss coefficients and associated base temperatures.

Application and interpretation

As there are numerous methods of calculating degree days which yield slightly different results, it is important that comparisons between buildings in different degree day climates are made with data calculated by the same method and using the same units. Published degree day data

should ideally include the applied base temperature and the units of measure (eg 1000 HDD18K). When the relationship between a building’s energy consumption and degree days is defined, degree days can be used to predict that building’s requirement for heating and cooling energy across various climatic zones. Degree days (or hours) can also be used to predict energy usage patterns in response to variation in climate, offering more responsive energy management. When considering published degree day values it is important to remember that while the value could correlate with the building’s energy demand over the considered period (monthly, seasonal or annual) there may not be a direct correlation to the installed heating or cooling system’s required peak demand or rated capacity. Peak demand control therefore remains a distinct consideration for which the local degree days indexes offer little insight.

Conclusion

This chapter offers a significantly simplified overview of the application of degree days. Complicating factors such as the effect of building mass on heating or cooling demands would require a more detailed study of the subject. For a fuller review of the subject the reader is referred to CIBSE TM 41 Degree-days: theory and application (Day, 2006).

References • •

108

Day, T. (2006). Degree-days: theory and application. doi: CIBSE TM41, London Strachey, R. (1878). Paper on the computation and quantity of heat in excess of a fixed base temperature received at any place during the course of the year to supply a standard comparison with the progress of vegetation. Quarterly Weather Report, Appendix II.

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THE USE OF GLASS IN BUILDINGS From Crystal Palace to Green Building

Dr Dirk Conradie, Steve Szewczuk


GLASS AND GREEN BUILDINGS

G

6

lass is an ancient material, dating back more than 5 000 years. It is believed that the material originated around 3 500 to 3 000 BCE in Egypt and eastern Mesopotamia (present day Iraq). Glass is a hard, brittle, usually transparent material composed of earthen elements that have been transformed by fire. The manufacturing process heats the raw materials until they are completely fused. They are then cooled quickly, becoming rigid without fully crystallizing. The resulting material contains properties of both a crystal (mechanically rigid) and a liquid (random, disordered molecular arrangement) but actually is different from either state (Bell et al., 2014). In 2013 the South African construction industry used 6.2 million m2 of glass for windows and facades and 0.6 million m2 of glass for doors, patios and showers. Consequently glass is a major item in the construction sector. It is therefore important that the characteristics of glass are well understood when designers, architects and builders select glass types. Currently, the usage of glass in South Africa is not considered as an important ‘energy efficient’measure. Ordinary windows are notorious for unwanted heat loss and heat gain and in most cases they will not be adequate for new building designs to meet SANS 10400-XA Energy usage in buildings. Factors such as placement of windows around the building and optimal orientation comes into play. Any mention of windows and hot climates inevitably results in the same statement – “open the windows”. Window technology has evolved over the years to the point where windows can be selected not only for their aesthetic qualities, but also for their performance abilities. For example, windows can be made from laminated glass that resists impact or have special

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coatings that control the amount of heat gain and loss, or prevent water spots and dirt accumulation. Previous chapters, Maximising the Sun (Conradie, 2011), Optimising Daylight in South Africa: A Case Study (Conradie, 2012), Designing for South African Climate and Weather (Conradie, 2012) and Appropriate Passive Design Approaches for the Various Climatic Regions in South Africa (Conradie, 2013) introduced the current South African climatic characteristics. From this it is clear that solar control such as sun shading of windows is an important passive strategy to ensure a comfortable interior. The extensive use of glazing in modern buildings also has a major impact on the energy efficiency of the building envelope. This chapter explores the types of and the appropriate use of glass in South African buildings within the context of a hot climate. The large scale use of glass in a building was pioneered in projects such as Crystal Palace that was originally erected in Hyde Park, London. It was a cast-iron and plateglass building erected to house the Great Exhibition of 1851. More than 14,000 exhibitors from around the world gathered in the Palace’s 92,000 m² exhibition space to

Figure 1: The Mies van der Rohe Barcelona Pavillion originally constructed 1929.


6

GLASS AND GREEN BUILDINGS

Resistance (CR) are also important and are also discussed below.

U-value (W/m²K) This measures how readily a window conducts heat. It is a measure of the rate of non-solar heat loss or gain through the window assembly. The rate of heat flow is indicated in the terms of the U-value of a window assembly which includes the effect of the frame, glass, seals and any spacers. The lower the U-value, the greater a window’s Figure 2: The extensive use of glass in the Oracle resistance to heat flow and the better its Software Company’s headquarter in the USA near San Francisco (Oracle Parkway, Redwood City, CA). insulating value. A low U-value is ideal for all climates as it stops unwanted heat gain in display examples of the latest technology summer and unwanted heat loss in winter. developed in the Industrial Revolution. In Scandinavia, overall window insulation Designed by Sir Joseph Paxton, the Great levels (frame and glass) as low as 0.8 W/m² Exhibition building was 564 m long, with K are targeted. This is approaching the limit Thismight measures how readily window conducts heat an interior height of 39 m. Because of the which be achieved withaconventional or gain through the combinations window assembly. recent invention of the cast plate glass technology by using suchThe as rate of h a window assembly which includes the effect of the method in 1848, which allowed for large quadruple glazing, low emissivity coatings the U-value, the greater a window’s resistance to he sheets of cheap but strong glass, it was at and insulating gasses. U-value is ideal for allaclimates as it stops This measures how readily window conducts heat. Itunwanted is a measu orwinter. gainthermal through the window assembly. rate of heat the time the largest amount of glass ever The transmittance of The windows is flow is ind a window assembly which includes the effect of the frame, glass, seen in a building and astonished visitors made up of three components, i.e. glass or the U-value, the greater a window’s resistance to heat flow and th In Scandinavia, overall window insulation levels (fra U-valueglazed is ideal for all (excludes climates as itframe stops unwanted gain in s with its clear walls and ceilings that did not double unit or sash),heat This is approaching the limit which might be achieve winter. require interior lights, thus a “Crystal Palace”. frame/sash and such the spacer between paneslow emiss combinations as quadruple glazing, Scandinavia, window insulation (frame and glass The popularity of large glazed areas was inInthe case of overall double glazed units.levels A basic This is approaching the limit which might be achieved with conven The thermal transmittance of windows is made up o further almost irreversibly boosted by iconic method to determine these component combinations such as quadruple glazing, low emissivity coatings unit (excludes or sash), frame/ sash is to use frame the formula (equation 1) and the s buildings of the modern movement such values The thermal transmittance windowsto is determine made up of three compo glazed units. A basic ofmethod these com as Mies van der Rohe’s famous Barcelona below (Buttonframe et al., sash), 1993):frame/ sash and the spacer unit (excludes betwee below (Button etoral., 1993): glazed units. A basic method to determine these component value Pavillion (1929), Farnworth House (1951) below (Button et al., 1993): located in Plano, Illinois and Philip Johnson’s A U g + Awf+U wf + P wf U s Glass House (1949) located in New Canaan, = g +A U wf U wf U w AgU g + P wf s Uw = Connecticut. A +A Ag Awf

Definitions

When one works with or designs for glass in buildings a number of definitions are important. The two most important ones from a thermal performance point of view are the U-value and Solar Heat Gain Coefficient (SHGC). Other factors that also play a role such as Air Leakage (AL), Visible Transmittance (VT ) and Condensation

where where

g

wf

transmittance = thermal transmittance UU =wthermal = projected areas of glazing in m² AAg = projected areas of glazing in m² = projected area of window frame or sash in m² A = projected area of window frame or sash in m UAwf= thermal transmittance of glazing (W/m² K) thermal transmittance of glazing (W/m² K) transmittance of window frame U g==thermal U w

g

wf g

wf

U =wflength of inner perimeter of window frame P or sash (W/m² K) wf

or (W/m² K) = sash thermal transmittance

of window frame

or sash (m)

= length oftransmittance inner perimeter window frame thermal due to of spacer UP=wflinear s

U

in multiple glazing or sash (m) units (W/m² K)

= linear thermal“Whole-Window” transmittance due to spacer To accurately determine and SHGC values of al s that has been developed in South Africa for Wispeco (Pty) Ltd can THE GREENglazing BUILDING HANDBOOK in multiple units (W/m² K) that it calculates the glass combined with a specific frame. It is av downloaded from the web. It is based on the extrusion systems a

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GLASS AND GREEN BUILDINGS

6

To accurately determine “Whole-Window” and SHGC values of aluminium windows or doors U-Solve that has been developed in South Africa for Wispeco (Pty) Ltd can be used. “Whole-Window” implies that it calculates the glass combined with a specific frame. It is available free of charge and can be downloaded from the web. It is based on the extrusion systems available from Wispeco in Southern Africa. U-Solve do not approximate the U-Values and SHGC Values. It calculates the actual values from detailed software simulations using the Therm and Window software available from the Lawrence Berkley Laboratories in the United States. U-Solve is the only program currently available in Southern Africa that performs these detailed calculations. U-Solve also incorporates the SANS 204 calculations that need to be performed for every new building being erected in South Africa. U-Solve is endorsed by SAFIERA and the calculations have been verified against “hot-box” testing by AAAMSA and SAFIERA. Solar Heat Gain Coefficient (SHGC) The U-value and SHGC are the two most important factors that determine the thermal performance of a window. SHGC measures how readily heat caused by solar radiation flows through a window. The SHGC is the fraction of incident solar radiation admitted through a window, both directly transmitted and absorbed and subsequently released inward. SHGC is expressed as a decimal between zero and one. The lower a window’s SHGC, the less solar heat it transmits. In cooler climates, a high SHGC is beneficial for north facing windows during winter, however shading will be required in summer to prevent unwanted solar heat gain. In hot climates a low SHGC is always ideal. When appropriate solar shielding or protection (Conradie, 2012) is applied to

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the building’s façade it impacts favourably on the SHGC aspect of the window. The fact that less direct solar radiation would reach the window will significantly reduce Whensurface appropriate solar shielding or protection the amount of solar radiationon that reaches impacts favourably the SHGC aspect of the the inside of the building.

the window surface significantly red2 Whenreach appropriate solar shielding or will protection (Conradie, impacts favourably on the SHGC aspect of the window. The of the building. Daylight factor surface will significantly reduce the amou reach the window When appropriate protection (Conradie, 2 The daylight factorsolar is theshielding ratio of or internal of the building. impacts favourably on the SHGC aspect of the window. The

factor light 2.3 level Daylight to external light level and is

reach the window surface will significantly reduce the amou defined as: 2.3 Daylight of the building. factor

The daylight factor is the ratio of internal light

⎛ E =⎞ ⎜ E ⎟ ×100 DF ⎟ ⎜×100 = ⎜ factor The is the⎟ DFdaylight ⎜ ⎟ ⎝ E ⎠ ratio of internal light level to extern ⎝ E ⎠

The factor 2.3 daylight Daylight factor ⎛ is the⎞ ratio of internal light level to extern i

i

o

⎛ Eoi ⎞ ⎜ ⎟ ×100 = DF where: ⎜ ⎟ where: where: E ⎝ o ⎠

E E E

= illuminance duedue to daylight aatpoint indoors = illuminance toatdaylight a point on = iilluminance todue daylight a onatthe where: i

point on the indoors working plane. = simultaneous illuminance = illuminance dueoutdoor to daylight at a point on the indoors i = simultaneous outdoor illuminance on a horizontal pla = simultaneous outdoor illuminance on a on ao horizontal plane from an unobstructed o overcast sky. hemisphere of overcast sky. illuminance on a horizontal pla sky.outdoor =overcast simultaneous

E

E

o

There are basically three paths (daylight factor components overcast sky. ThereThere basically three paths (daylight inside aare room, i.e.basically through a three glazed window, roof lightfacto or ap are paths (daylight factor components) along which light can • The sky component (SC) that is direct light from a room, i.e.paths through a glazed window,paro Thereinside are basically three (daylight factor components reach point inside a room, i.e. through a (ERC) • aa The externally reflected component lig inside room, i.e. through a glazed window, roof orisap • reaching The sky component (SC) thatlight isthat direct then the internal pointisas measured. glazed roof light or(SC) aperture • window, The sky component that direct light from pa • The externally reflected component (E •• The follows: The internally externallyreflected reflectedcomponent component(IRC) (ERC)that thatisisligh lig then reaching the internal point measu reaching the point only after reflection from an inter • The sky (SC) that ispoint direct thencomponent reaching the internal measured.

• internally Theofinternally reflected (IR light from part the sky or sun at the component • The reflected component (IRC) that is ligh The sum of thereaching three components gives theafter illuminance leve only reflection reaching the pointthe onlypoint after reflection from an inter point considered. daylight factor only gives the proportion of daylight from out • The externally reflected building and does not indicatecomponent the absolute level of illuminat The(ERC) sum theisthree components givesanthe illuminance Theof sum oflight the three components gives thelev ill that reflected from daylight factor only gives the proportion of daylight from out daylight factor only gives the proportion of day exterior surface and then reaching the To calculate daylight factors requires complex repetition of c building and does not indicate the absolute level of illumina software product such as Radiance. This the is a suite of tools building does not indicate absolute levf internal pointand measured. includes a rendererreflected as well ascomponent other tools for measuring the • The internally To calculate daylight factors requires complex repetition of to perform allislighting calculations. Thethe design daycomplex used for (IRC) light entering through To that calculate daylight factors requires software product such as Radiance. This is a suite of tools standard Commission Internationale de l’Eclairage (CIE) ov window but reaching thesuch point onlyRadiance. after for measuring includes a renderer as well as other tools software product as This is the a where the ground ambient light level is 11921 lux. Since the to perform allfrom lighting calculations. The design used reflection internal surface. includes a an renderer as well otherday tools forform orientation effects, the estimates of theasdaylight contribution standard Commission Internationale de l’Eclairage ov to perform lighting calculations. The (CIE) design orientation factors all have been derived to be applied to the da where theof ground ambient light levelgives is 11921 lux. Since the The sum the Commission three components derived a standard based on theInternationale spatial distribution of daylig standard de l’Eclai orientation effects, the estimates of the daylight contribution the illuminance in alux (CIE, 2002). Rooms with DFatofthe 2%point are considered day lit. where thelevel ground ambient is 11921 orientation factors have been derivedlight to belevel applied to the d well day lit when the DF is above 5%.gives of the dayligh measured. The daylight factor only orientation derived a standardeffects, based onthe theestimates spatial distribution of dayli (CIE, 2002). Rooms with a DF of 2% are considered day lit. orientation factors have been derived to be ap well day when the DF is 5%. Table 1: lit Various levels ofabove Daylight Factor derived a standard based on the spatial distrib

(CIE, a DF of 2% are cons Average DF2002). Rooms with Appearance day lit levels when of theDaylight DF is above Tablewell 1: Various Factor 5%.


6

the proportion of daylight from outside that reaches the interior of the building and does not indicate the absolute level of illumination that will occur. To calculate daylight factors requires complex repetition of calculations. It is normally undertaken by a software product such as Radiance. This is a suite of tools for performing lighting simulation which includes a renderer as well as other tools for measuring the simulated light levels. It uses ray tracing to perform all lighting calculations. The design day used for daylight factors is based upon the standard Commission Internationale de l’Eclairage (CIE) overcast sky for 21 September at 12h00 and where the ground ambient light level is 11921 lux. Since the CIE standard overcast sky assumes no orientation effects, the estimates of the daylight contribution can be wrong. To correct for this, orientation factors have been derived to be applied to the daylight factors. More recently the CIE has derived a standard based on the spatial distribution of daylight, i.e. the CIE Standard General Sky (CIE, 2002). Rooms with a DF of 2% are considered day lit. However a room

GLASS AND GREEN BUILDINGS

is only considered as well day lit when the DF is above 5%. Visible Transmittance (VT) This measures how much light comes through a window. It is an optical property that indicates the amount of visible light transmitted through a product. While VT theoretically varies between zero and one, most values are between 0.3 and 0.8. The higher the VT, the more light is transmitted. A high VT is desirable to maximise daylight. Select windows with a higher VT to maximise daylight and view. Condensation Resistance (CR) This measures how well a product resists the formation of condensation. CR is expressed as a number between one and 100. The higher the number, the better a product is able to resist condensation.

Types of glass

There are two main flat glass manufacturing methods for producing the basic glass, i.e. float and rolled glass. More than 90% of the world’s flat glass is made by the

Average DF

Appearance

Energy Implications

< 2%

Room looks gloomy

Electric lighting needed most of the day.

2% to 5%

Predominantly day lit appearance, but supplementary artificial lighting is needed.

Good balance between lighting and thermal aspects.

> 5%

Room appears strongly day lit.

Daytime electric lighting rarely needed, but potential for thermal problems due to overheating in summer and heat losses in winter Table 1: Various levels of Daylight Factor

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6

Figure 3: Solar transmission through glass (After Terri Meyer Boake) The figures used in this figure are not necessarily identical in terms of fenestration used in South Africa, but serves to illustrate the principles.

float process (Button, 1993). Molten glass, at approximately 1000 째C, is poured continuously from a furnace on to a large shallow bath of molten tin. It floats on the tin, spreads out and forms a level surface. Thickness is controlled by the speed at which the solidifying glass ribbon is drawn off the bath. After annealing the glass emerges as a fire polished product with almost parallel surfaces. There are three forms of modification to abovementioned manufacturing processes, i.e. tinting, coated and wired. Additionally advanced primary processing can be applied. This is treatment after its manufacture such as heat treatment, bending and surface working. For example toughened glass or tempered glass is produced by heating annealed glass to approximately 650 째C where the glass begins to soften. The outer

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surfaces are then cooled rapidly, thereby creating in them a high compression. The bending strength is usually increased to a factor of four or five times that of annealed glass. When this glass is broken, it fractures into harmless fragments and is seen as a safety glazing material. Heat strengthened glass is similarly produced, but approximately half the strength of toughened glass and without the safety glazing characteristics. Secondary processing includes surface printing, off-line coating and the creation of multiple glazed units and lamination. Glass can even be configured to reduce noise or sound penetration. Low emissivity (Low-E) glass Glass attempts to control solar heat radiation from the sun by reflectance, transmittance and absorptance. For solar control purposes


6

these are defined in terms of the following parameters (Figure 3): • Reflectance – the proportion of solar radiation reflected back into the atmosphere. • Direct Transmittance – the proportion of solar radiation transmitted directly through the glass. • Absorptance – the proportion of solar radiation absorbed by the glass. • Total Transmittance (also known as g value). This is the proportion of solar radiation transmitted through the glass by all means. This is composed of the direct transmittance and that which is absorbed by the glass and re-radiated inwards. Figure 3 illustrates the different solar mechanisms for clear glass, heat absorbing glass and reflective glass or low-E glass. Window glass is by nature highly thermally emissive. To improve thermal efficiency (insulation properties) thin film coatings are applied to the raw soda-lime glass. There are two primary methods in use are pyrolytic chemical vapour deposition (CVD) and magnetron sputtering. Pyrolytic coatings are usually applied at the float glass plant when the glass is manufactured. The second involves depositing thin silver layers with antireflection layers. Magnetron sputtering uses large vacuum chambers with multiple deposition chambers depositing five to 10 or more layers in succession. Silver-based films are environmentally unstable (soft) and must be enclosed in insulated glazing or an Insulated Glass Unit (IGU), commonly known as double-glazing to maintain their properties over time. Specially designed coatings are applied to one or more surfaces of insulated glass. These coatings reflect radiant infrared energy, thus tending to keep radiant heat on the side of the glass where it originated,

GLASS AND GREEN BUILDINGS

while letting visible light pass. This results in more efficient windows because radiant heat originating from indoors in winter is reflected back inside, while infrared heat radiation from the sun during summer is reflected away, keeping it cooler inside. If low-E glass is used on its own the coating can get damaged if the window is not washed with the right chemicals. If low-E glass is used on its own the coated surface should preferably on the inside. The authors express the opinion that it would be better practice to use low-E glass in IGU units or double glazing where the reflective coating surface can be turned to the inside of the unit and be protected. Corrosion is also a problem in aggressive environments. Since energy-efficient fenestration such as low-E reflect much more sunlight than simple glass windows, when these windows are somewhat concave they can focus sunlight and cause damage. Another unintended side-effect is that Low-E windows may also block radio frequency signals. Buildings without distributed antenna systems may then suffer degraded cell phone reception.

Comparison of typical fenestration in South Africa

Table 2 illustrates six typical South African window profiles and glass configurations and the U-values that can be attained. The U-solve software was used to generate the comparisons. It is apparent how little real improvement in U-value is attained by increasing the thickness of glass. Simulations 3 and 5 are identical except that 5 is using low-E glass. Similarly simulations 4 and 6 are identical except that 6 is using low-E glass. When designing the fenestration for a building the relevant sections of SANS 204 should be studied. These sections are 4.3.4 Fenestration, 4.4.3 Permissible air leakage (AL), Annex C (normative) Fenestration

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GLASS AND GREEN BUILDINGS

6

No.

Type of Glass

Frame

U-value whole window (W/m² K)

U-Value Centre of Glass (W/ m² K)

SHGC

1

PFG Clearvue 4 mm

Casement 38

6.14

5.879

0.661

2

PFG Intruderprufe 6.38 mm

Casement 38

6.01

5.749

0.637

3

PFG 20 mm Clearvue Insulated Glass Unit (4 mm + 12 mm air gap + 4 mm)

Casement 38

3.77

5.729

0.580

4

Casement PFG 25 mm 38 Intruderprufe Insulated Glass Unit (6.38 mm = 12 mm + 6.38 mm)

3.68

2.673

0.537

5

PFG 20 mm Clearvue Insulated Glass Unit Low-e 94 mm + 12 mm air gap + 4 mm)

Casement 38

3.05

0.679

0.526

6

Casement PFG 25 mm 38 Intruderprufe Insulated Glass Unit (6.38 mm = 12 mm + 6.38 mm low-e)

2.99

1.878

0.486

Table 2: Typical window configurations generated by means of the U-value software

for buildings with natural environmental control - Solar exposure factor for each glazing element, Annex D (normative) Fenestration for buildings with artificial ventilation or air conditioning and Annex E (normative) Requirements for the glazing assessment.

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Conclusions

The article attempted to quantify the characteristics of glass. Although there are very high performance fenestration systems available, the client will pay a substantial premium if glass is overused or ignores the characteristics of the particular


6

climate. From the analyses it is evident that small increases in the thickness of the glass elements do not significantly improve the thermal performance. It is evident that fenestration in a hot country such as South Africa should be carefully considered and

GLASS AND GREEN BUILDINGS

used in conjunction with appropriate solar protection. The rhetorical question is asked if it is really necessary to use the excessive amounts of glass as illustrated above in Figure 2 in a hot and sunny country such as South Africa.

References • • • • • • • • • • •

The contribution of Stephen Levenderis, developer of U-Solve, from Stargate Computing and Electronics is gratefully acknowledged. References Bell, V.B. and Rand, P. 2014. Materials for Architectural Design. Laurence King Publishing, pp. 11-15. Button, D. and Pye, B. 1993. Glass in Building – A Guide to modern Architectural Glass performance. Butterworth Architecture, Reed international Books. CIE DS 011.2/E:2002. 2002. Spatial distribution of daylight - CIE standard general sky. Commission Internationale de l’Eclairage. Conradie, D.C.U. 2011. Maximising the Sun. In Green Building Handbook, Volume 3, pp. 147159. Conradie, D.C.U. 2012. Optimising Daylight in South Africa: A Case Study. In Green building Handbook, Volume 4, pp. 101-119. Conradie, D.C.U. 2012. Designing for South African Climate and Weather. In Green Building Handbook, Volume 4, pp. 181-195. Conradie, D.C.U. 2013. Appropriate Passive Design Approaches for the Various Climatic Regions in South Africa. In Green Building Handbook, Volume 5, pp.101-117. Wikipedia. 2015. The Crystal Palace. http://en.wikipedia.org/wiki/The_Crystal_Palace, Accessed on 22 January 2015. Wikipedia. 2015. Low-emissivity windows. http://en.wikipedia.org/wiki/Low_emissivity. Accessed on 13 February 2015.

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PROFILE PROFILE

NEW RECYCLING TECHNOLOGY BOOSTS BELGOTEX’S GREEN CREDENTIALS Belgotex Floors have once again proven they are green at heart with the installation of a new Erema INTAREMA® 1007 TE recycling line, boosting their growing green credentials. The R5-million Erema machine recycles production waste back into recycled pellets for conversion into Eco fibre – a valuable raw material used in the production of carpet ranges. Belgotex are the first company to employ the innovative INTAREMA® recycling technology in South Africa, enabling them to manage the recycling process entirely in-house, save costs and reduce the strain on natural resources in line with their Environmental Policy. “We’re always looking at ways to reduce our input consumption of raw materials and manage our waste outputs. This new line enables us to use recycled fibre instead of buying in virgin polymer, without any loss of quality,” says Kevin Walsh, chief operating officer at Belgotex Floorcoverings. Combining a cutter and compactor with an extruder for the first time ever, the new technology makes it possible to cut, compact and extrude waste plastics in a single, continuous process. Its’ innovative “Counter Current” system means the machine can handle more material in a shorter time, is more independent in terms of the pre-compacting

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level of material and has a considerably higher temperature range which translates into higher productivity, flexibility and process stability. In addition, the inclusion of ecoSAVE® motors make it the only recycling machine on the market to offer up to 20% energy savings, resulting in lower production costs and reduced CO2 emissions. Effectively reducing Belgotex’s waste rates from their carpet production processes to close to zero, the Erema line is already processing about 200kg of material per hour, converting waste into high quality pellets which are then extruded into Eco Fibre. This Eco fibre is then used in our carpet ranges. This allows for a higher recycled content of the total weighted area and earns higher points on the Flooring Calculator for the Green Star-Interiors V1 rating tool. www.belgotexfloors.co.za PMB (033) 897-7500 CPT (021) 763-6900 JHB (011) 380-9300 Facebook: www.facebook.com/belgotex Twitter: @ belgotex


MATERIAL EFFICIENCY AND THE 3 RS

Llewellyn van Wyk


MATERIAL EFFICIENCY

7

S

ignificant pressure is being brought to bear on material manufacturers to green the materials and products produced by industry in general – and the construction sector is no exception, for good reason. The construction industry and its products are responsible for the following environmental impacts, namely: • 45% of global energy generated is used to heat, light and ventilate buildings and 5% to construct them; • 40% of water globally is used for sanitation and other uses in buildings; • 70% of global timber products end up in building construction (Edwards 2002:10). Apart from these impacts, there are other environmental impacts arising out of material use including the consequences of mining (including pollution and contamination of water, soil and air); the need for mining rehabilitation at end-of-life; the toxins, including volatile organic compounds and ozone depleting substances, produced for, used in, and emitted by the manufacturing process; and the disposal of waste products during the construction period and at end-of-life. While green (or greener) materials should demonstrate a significant reduction in all of the above, chemicals, water and energy will

Resource

still remain embodied in the material. Thus, any saving in material represents a reduction in environmental impact. Truly, the time has come to employ the phrase “less is more”, a term coined by Robert Browning in the 1855 poem ‘Andrea del Sarto’, and later adopted by Mies van der Rohe as a precept for minimalist design. The purpose of this chapter is to make building designers aware of how to reduce environmental impacts by improving material efficiency particularly through recycling, reuse, material substitution, maintaining existing products for longer, re-using components from unwanted products, and designing products with less material through light-weight design or dematerialisation.

Material efficiency

Material efficiency can be described as “the pursuit of technical strategies, business models, consumer preferences and policy instruments that will lead to a substantial reduction in the production of high-volume, energy-intensive materials required to deliver human well-being” (Allwood, Ashby, Gutowski and Worrell 2013). Allwood et al correctly argue that the motivations for material efficiency include reducing energy demand, reducing the emissions and other

Consumption

Material resources incorporated in the built 363.4 Mt environment Energy used

7.8 Mt of oil equivalent

Wastes generated

151.0 Mt

Emissions generated

28.0 Mt

Table 1: Total resource use in UK construction industry

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7

MATERIAL EFFICIENCY

Resource

Consumption

Primary materials and products

295.5 Mt

Secondary materials and products

21.6 Mt

Recycled materials and products

43.0 Mt

Reclaimed materials and products

3.3 Mt

Total

363.4 Mt Table 2: Total material resource use in UK construction industry

Material/product

Total Used (Kt)

Quarry products

125,871

Cement, plaster, etc.

97,992

Stone and other non-metallic mineral 43,631 products Bricks and other clay-based products

5,979

Ceramic products

4,313

Fabricated metal products

3,938

Finishes, coatings, adhesives, etc.

1,447

Glass-based products

1,415

Plastic products

1,402

Cabling, wiring and lighting

190

Total primary material resource use

295,450 Table 3: Total primary material resource use

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environmental impacts of industry, and increasing national resource security. The industrial sector accounts for almost one-third of global energy demand with most of that energy required for the production of bulk materials (Allwood et al 2013). The headline figures for material resources incorporated in the built environment, and wastes and emissions generated, by the UK construction industry in 1998 (Smith, Kersey and Griffiths 2002) are as shown in table1. To identify material efficiency opportunities the total resource use must be further broke down as shown in Table two. As the opportunity to achieve higher material efficiency is located in primary materials and products (it constitutes over 80% of total material resource use), a further breakdown is provided in Table 3. As can be seen from table three, a staggering 94% of primary material resource use is ascribed to products used essentially in wet works of construction (stone, sand, cement, clay). It is unfortunately also the area most difficult to control. Although gains can be made through modular design, significant gains will only come about through changing construction methods. While many bulk material manufacturers have taken significant steps to reduce the energy consumption of their production facilities, the reality is that further energy reductions are not really possible without a) significant technological breakthroughs with regard to these current production processes and/or, b) the development of a next-generation of bulk materials with a significantly lower energy footprint. While both of these hold promise, reducing the throughput of virgin raw materials is a critical immediate goal in reducing energy use and emission, and a key strategy in material efficiency. Allwood et al note that there are a number of steps

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that can be taken to achieve this including increasing recycling, material substitution, maintaining existing products for longer, re-using components from unwanted products, designing products with less material through light-weight design or dematerialisation, and switching to renewable energy.

Recycling

Recycling is the process whereby waste materials are changed into new products or components thereby preventing the waste of potentially useful materials, reducing the consumption of fresh raw materials, reducing energy usage, reducing pollution and reducing landfill. Recycling has become a key component of modern waste reduction although it is by no means unique to contemporary society: archaeological excavations provide ample evidence of materials or products being recycled, especially during periods of scarcity. Recycling is a fundamental part of the shift toward a green economy with its focus on zero waste. It is also the third component of the “Reduce, Reuse and Recycle” hierarchy. As noted by the Northern California Compactors “these products are recycled by converting them into items worth using for the second time. This is typically done by breaking down the product into its raw materials and reusing them to manufacture something new or similar to the old product. When customers purchase products made from recycled material, the overall environmental benefits are multiplied as less energy and resources are consumed in manufacturing these products as compared to the goods that are manufactured for the first time” (Environmental Expert 2013). Though reusing products or reducing their consumption in the first place can possibly have greater long-term benefits, recycling and composting are the perfect


7

means of managing the discarded items and other kinds of waste. In a majority of cases, the prime difference between these two techniques pertains to the materials involved – manufactured or organic (Environmental Expert 2013). Much of what is used in the building process can be recycled: in the Menlyn-onMaine development in Pretoria where over 200 houses were brought down to make way for a new inner-city development, the bottom structures of the houses were all recycled through careful deconstruction rather than demolition. Foundation walls and slabs were recycled as base course for the roads and for underslab filling in the new buildings. Regrettably, despite its potential, levels of metals recycling are generally low (UNEP 2010). In reality, the metals available in society constitute an ‘above ground mine’ which, if recycled strategically, could shift metal stock use from below ground to above ground. The quality of the recyclates are key to the success of recycling: for example, clear glass is preferred over coloured glass for recycling, and polished steel over coated steel as the coating has to be removed first. Designers can assist the recycling process by keeping their material palette simple, for example, using polished steel or aluminium hand railing or framing rather than finishing the rail with a coating. A higher quality recyclate is more likely to be recycled, thereby offering significant benefits including reducing environmental impact, supporting economic growth by maximising value, returning higher value to the recycling industry, and boosting consumer and producer confidence in the waste and resource management sector which will also encourage investment in that sector (DEFRA 2013). Protecting recyclate quality and avoiding cross-contamination

MATERIAL EFFICIENCY

is one of the reasons why green building assessment systems require that waste be separated. As noted by the Northern California Composters, “recycling, in its own, is a very large industry that employs more than one million workers who are paid about $37 billion per year, employed by companies who are making a profit of over $236 billion every year” (Environmental Expert 2013).

Re-using components from unwanted products

Reuse is to use a component or product again, either for the same function or for a different function, after it has been used. Reuse is one of the easiest strategies aimed at decoupling natural resource use and environmental impacts from economic growth. A desktop review undertaken by the CSIR (2005) indicated that substantial efforts were and are increasingly underway in South Africa in pursuit of recycling and the reuse of materials generally, and construction products specifically. Much of what is used in the building process can be reused: in the Menlyn-onMaine development case study cited earlier, the top structures of the houses were all reused through careful deconstruction rather than demolition. Roof tiles and sheets, all roof timbers, insulation, rain water goods, fascia boards, bricks, fenestration and doors, steel, plastic, sanitaryware, floor finishes and wall finishes were all made available for reuse . The case study below is indicative of the circumstances under which reuse is optimal. In this case study a condition of the refurbishment contract was to recover the face bricks used in the interior partitioning of the building. However, the contractor – who is a specialist in this field – recovered, in addition to what was called for in the tender, a quantity of aluminium scrap, face

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Ground Floor, Block 2A Tyger Terraces 2 DJ Wood Way, Bellville, 7530 Cape Town, South Africa Tel. +27 (21) 948 1877 / 2593 Fax +27 (21) 948 3455 e-mail: info@avna.co.za www.avna.co.za

• •

g r e e n b u i l d i n g d e s i g n • e n e r g y c alc ulat i o n • gr e e n r at ing specif ication • life cycle assessment • gr een build document at ion

• •


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MATERIAL EFFICIENCY

Materials

Quantity

Bricks, ROK

30,000

Ceilings, acoustic panels

250 sq.m.

Ceilings, tees

250 sq.m.

Doors

30

Partitions, boards

200

Partitions, studs

240

Power skirting

110 lengths

Sanitary ware

9 sets

Tiles, wall

120 sq.m. Table 4:Case study

bricks, carpets, ducting, insulation, and pine as well as meranti timber was recovered. The measured quantity of recovered material is listed in table 4. Based on the expertise of the contractor and the incentive offered by the client the recovery rate achieved for ROKâ&#x20AC;&#x2122;s was 80%, and 15% for face bricks. On this basis, this particular contractor would have a 50% advantage over another contractor based on the value of recyclable material alone. In reality, the advantage will most probably be higher than that as the transport costs for some of the new materials will be higher than those of the equivalent recycled material. It must be remembered that in developing countries, unlike developed countries, very little construction waste from a construction site is actually wasted: most of the bulk materials used in the construction sector such as aggregates, steel, aluminium, timber, pvc, cement fibre, and clay-based products, is salvaged and reused in low cost and informal settlements. For this and

other reasons, the use of recycled materials presents similar difficulties to those of industrial waste. Given the dispersion pattern of construction waste, and the difficulty of collection, it is unlikely that the use of salvaged building materials could be undertaken on a national scale and in sufficient quantity to make a significant contribution to the objectives of this study. Therefore while the reuse of construction materials is to be encouraged, this activity will be most effective at the local level.

Reducing the throughput of virgin raw materials Material substitution

The desktop review undertaken by the CSIR in 2005 revealed substantial activity in the use of industrial waste that lead to the conclusion that the application of material substitution through the use, for example, of industrial waste are driven in large part by the financial cost and environmental

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Klip-Tite Roofing Solutions:

IMPROVED DESIGN DELIVERS A SMARTER SOLUTION

Klip-Tite Innovation

the pan is reduced, increasing the wind uplift resistance of the sheet. These transverse pan stiffeners are a first in the South African sheeting market.” Testing conducted on the new profile showed improved wind uplift resistance results when compared with GRS’s existing Klip-Lok 700 product. Klip-Tite Innovation

Klip-Tite is a product that has been developed through continuous in-house testing of existing products, with the realisation that failure is normally caused by the sheet unclipping from the fixing clip, during high wind uplift pressure. Through rigorous testing, GRS’s technical team found that the weak point of sheeting is the flat (wide) pan, which is ‘sucked’ upwards causing dimensional changes and eventual failure. “During the applied upwards pressure, the pan deflects upwards in the form of a bow, causing the edges of the pans to rotate inwards, which increases the width of the narrow rib and allows the narrow rib indentations to slip over the clip,” says Johan van der Westhuizen, Deputy Chairman, Global Roofing Solutions. Methods to stiffen the pan were evaluated, prompting GRS to introduce an improved locking product, called Klip-Tite. Vd Westhuizen explains: “We have replaced the traditional longitudinal pan stiffeners with transverse stiffeners, to form structural members spanning across the width of the pan. The deflection of

Conservatively, the ultimate wind uplift resistance of KlipTite is 1.8kPa compared to 1.6kPa for KL700. Klip-Tite has already been supplied in various projects, including the Nicolway Shopping Centre, Pepkor building, Value Logistics distribution centre and Cell C headquarters

So when you’re looking for roofing solutions, get smart with GRS. Talk to us, The Smart Roof People on 011 898 2900 or visit www.globalroofs.co.za or email info@globalroofs.co.za

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implications to the enterprise of producing and discarding waste. Improved input to output ratios, stringent environmental regulation, dwindling landfill capacity and high transport costs are growing pressures that are increasingly impacting on all industries with the objective of eliminating waste. Various attempts have been made in the building sector with regard to material substitution, most notably the work of the acclaimed Japanese architect Shigeru Ban. Ban works with cardboard tubes (see Figure 1) to quickly and efficiently provide emergency shelter: the use of paper and cardboard is related to its availability in a post-disaster scenario compared to conventional materials. Given the 2005 CSIR review of the use of industrial waste for construction purposes, one can draw two conclusions. Firstly, it is to be expected that the generation of waste will progressively continue to reduce, and the limited residual waste will increasingly be used to generate added value through the manufacture of new products. Secondly, due to the nature and location of the waste, it is difficult to centralise sufficient material to enable a new product to be manufactured. Future product development in this field will therefore occur in specific response to the opportunities offered by the type and

Figure 1: Takatori Catholic Church, Kobe, 1995 Source: Wikimedia

MATERIAL EFFICIENCY

location of the waste material. For these reasons, it is unlikely that the use of industrial waste as a resource for the manufacture of new mainstream construction products holds any significant promise in terms of energy and emission reduction.

Maintaining existing products for longer

An obvious way of reducing material use is to use materials that will last for as long as possible. Fortunately, the construction sector is one of the sectors where this is generally the case â&#x20AC;&#x201C; infrastructure is designed to last because of the high cost of construction. Notwithstanding this, the lifespan of these materials can be extended by the way they are installed, and finished. Epoxy-coated steel or aluminium is more difficult to reuse than polished steel or aluminium since in the former instance the finish must first be removed which may, in itself, be material intensive. Choosing a low maintenance finish will reduce material intensity in terms of ongoing maintenance, and extend the lifespan of the material. A wall built from facebrick will over its life cycle require far less resource use than a wall built of run-of-the-kiln bricks that are plastered and painted. Although timber may often last for many decades, using it in harsh conditions will result in premature degradation and thus replacement, at worst, or frequent maintenance, at best. Since buildings are generally designed for long life, it is possible to reuse buildings rather than to demolish them. In many cities reusing warehouses has become fashionable: this is particularly so in cities with a waterfront where warehouse and other industrial-type buildings were located either along a river or the sea. Heritage buildings are similarly highly reusable in part because they are located in historic quarters of the city and because they are often also

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MATERIAL EFFICIENCY

Figure 2: Heritage Square, Cape Town

7

protected by law. However, most buildings can be reused, and where this is not possible or desirable, components of a building can be reused including, at a minimum, floors, columns, beams and load bearing walls. Very often facades and fenestration can also be reused, and, again, where not possible or desirable, those components can be removed and reused elsewhere, or recycled. Heritage Square in Cape Town is a fine example of extending the life of existing products: this collection of 18th century town houses, associated outbuildings and a warehouse on Bree Street (once earmarked for demolition to make way for a new parking garage) was redeveloped through a combination of restoration and careful insertion of new uses. Not only were significant gains made in terms of resource use, but an irreplaceable artefact of Cape Town’s heritage was retained for the benefit of future generations.

Dematerialization

Figure 3: Ultra-thin concrete raft slab

Figure 4: CSIR designed house, Kleinmond

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Dematerialization of a product literally means using less – preferably no – material. Although the latter sounds unfeasible in the construction sector, ultimately the shift from a reliance on products to services is the process of dematerialization. A good example of this is hot-desking, i.e. where a working space is shared between two or more people. Another example would be car-pooling. The basic idea is simple: relieve ecosystems of the demands made by man by using less virgin raw material (Aachener Stiftung Kathy Beys 2015). Japan is one of the countries that have adopted dematerialization and resource efficiency as an economic and societal strategy through its Junkangata Shakai (sound material-cycle society) programme in 2000. Their Fundamental Law for Establishing a Sound Material-Cycle Society of 2000 emphasises a utilization hierarchy beginning “with resource reduction, on to reuse, material recycling, thermal recycling and final disposal” (Wuppertal Institute 2008:7). In architecture dematerialization involves designing with a view to achieving the same outcome while using less material (less is more). As Brown and Lutz-Carrillo (2009:2) note


7

â&#x20AC;&#x153;dematerializing the built environment as a goal for the way we approach the world leads to a re-examination [of ] the necessity of building in the shifting environment, designing for things like flexibility, durability, and deconstructability as well as the particular materials and resources used for the manufacture and operation of a particular building.â&#x20AC;? Brown and LutzCarrillo argue that there are three steps to dematerialization of the built environment: the first is to evaluate which buildings and building typologies are still relevant and abandon those which have become obsolete; the second is to re-evaluate the nature of the necessary buildings with the objective of meeting multiple needs with one structure or space; and the third is to find innovative ways of reducing the quantity of materials needed in the built environment and engineer buildings to operate more efficiently (2009:2). In an experimental house designed by the CSIR and built on the Built Environmentâ&#x20AC;&#x2122;s Innovation Site in Pretoria (see Figure 3), redesigning the slab from the conventional 100mm thickness to a 50mm thick Continuously Reinforced Ultra-thin Concrete Pavement (CRUCP) reduced the amount of concrete used by 2 cubic meters. A further reduction of 3.5 cubic meters of concrete was made by replacing conventional strip foundations with a raft slab providing an overall saving of 5.5 cubic meters of concrete or 13.42 metric tonnes. Brown and Lutz-Carrillo also posit an argument for rematerialization which involves the use of materials that are designed and manufactured for reuse (2009:3).

Designing out Waste

Designing out waste can be done through designing with regard to the dimensions and properties of the material being used,

MATERIAL EFFICIENCY

designing on a modular basis, and designing for disassembly. Designing with the dimensions and properties of the material to be used requires that the material dictates the component being designed, not the other way around. Floor and wall tiling is a case in point: too often designers do not set the floor or wall dimensions to match those of the floor or wall finish, especially where use is made of individual components such as tiles. Secondly, the design of the floor pattern ignores the dimensions and shape of the tile resulting in extensive cuttings, most of which is of a dimension which restricts its future use and results in the cutting being dumped. It is possible to design in a manner that minimises cutting: the dimensions of the rooms of the low income house designed by the CSIR was based on the dimensions of the walling element, in this case, hollow concrete masonry blocks (see Figure 4). As can be seen in the illustration, use is made of full blocks and half blocks: as a result, cutting is eliminated (there is no visible sign of cut blocks around the construction site), and because of this the time to erect this house was 50 per cent less than a comparable house built by the same construction crew a few months earlier. Not only was there a significant reduction in material, but also in time, the two main cost centres in construction.

Designing for resilience

Resilience is an ecological term used to describe a circumstance where an organism is able to withstand impacts which would ordinarily force it into another state. Climate change is likely to give rise to impacts which could push a number of organisms into an altered state, perhaps even to collapse. Building resilience is an inherent objective of an adaptation and mitigation strategy: in the building sector resilience has to do with

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withstanding impacts arising from climate change like higher wind speeds. If the actual loads exceed the design loads buildings will fail, with a concomitant material damage and loss. Incorporating resilience into building design and construction includes ensuring that the building is not located in areas that are, or will become, vulnerable to climate change impacts, i.e. coastal areas and/or areas of likely land slippage. Secondly, designing in anticipation of climate change will involve anticipating higher structural loads arising from higher wind speeds. Thirdly, building resilience will include designing buildings that are easily adaptable to changing functional requirements (loose-fit) to minimise potential material loss arising from future alterations.

MATERIAL EFFICIENCY

Conclusion

From a resource perspective, the greenest building is probably the building not built: the second greenest building is arguably an existing building where the resource use is already accounted for. Where a new building is required, or where alterations and additions are made to an existing building, a design approach aimed at minimizing resource use is an imperative if the ecological footprint of homo sapiens is to be kept within planetary boundaries. Fortunately, as this chapter demonstrates, there are a number of strategies that can be employed that have demonstrated that it is possible to substantially reduce resource consumption while achieving the same outcome.

References • • • • • • •

• •

Aachener Stiftung Kathy Beys 2015. Dematerialization. [Online] Available from: http://www. dematerialization.org/cms.php?id=4&lng=english [Accessed: 2015-02-16]. Allwood JM, Ashby MF, Gutowski TG, Worrell E., (2013). “Material efficiency: providing material services with less material production.” Phil Trans R Soc A 371:20120496. http://dx.doi. org/10.1098/rsta.2012.0496 Brown, M. and Lutz-Carrillo, S. 2009. Dematerialization – a changing paradigm in architecture. [Online] Available from: http://repositories.lib.utexas.edu/bitstream/handle/2152/11696/4Brown_Lutz-Carrillo-Dematerialization.pdf?sequence=2 [Downloaded: 2015-02-16]. CSIR (2005). The use of agricultural crops, industrial waste and recycled materials in construction, CSIR, Pretoria. PDP TH/2004/020. DEFRA 2013. Quality action plan proposals to promote high quality recycling of dry recyclates. London: Defra. Edwards, B. 2002. Rough guide to sustainability. London: Royal Institute of British Architects. Northern California Compactors 2013. Composting versus recycling: drawing the line to differentiate between the two waste. [Online] Available from: http://www.environmental-expert. com//articles/composting-vs-recycling-drawing-a-line-to-differentiate-between-the-twowaste-403319?utm_source=Articles_Waste_Recycling_01012014&utm_medium=email&utm_ campaign=newsletter&utm_content=feattextlink [Downloaded: 2014-01-08]. Smith, R., Kersey, J. and Griffiths, P. 2002. The construction industry mass balance: resource use, wastes and emissions. London: Ciria and Viridas. UNEP 2010. Metal Stocks in society – scientific synthesis 2010. New York: International Resource Panel, United Nations Environment Programme.

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PROFILE

GLASS SUSTAINABILITY

REDUCING CARBON EMISSIONS OF RESIDENTIAL EMITTERS Stephané Burger Interior Designer Shaluza Projects

How green is glass? The answer to the question is transparent, due to research and development put towards creating a product which not only provides the traditional properties of glass, but also environmental and structural properties which increase the use of glass as a major construction material that can be related to other materials like steel and brick. South Africa, as a developing country, has a long road ahead to create this awareness and although there exists regulations like SANS 10400 –XA and carbon tax legislation, most people are either unaware of ill informed.

CHANGES IN SOUTH AFRICAN BEHAVIOUR The General Household Survey of 2007 by Stats SA indicated that 58% of all households use electricity from mains for heating. With dramatic changes in the supply and demand of electricity in South Africa, it is virtually impossible to overlook the fact that a major shift in electricity consumers behaviour can lead to a massive reduction in CO2 emissions. Small shifts in paradigm has resulted in a major roll-out of solar water heaters being installed throughout the country and people using alternative means to produce energy used in residential applications. 2011 Marked the year which South Africa has joined countries worldwide that have incorporated ecological responsible requirements to standards in the built environment, thereby acknowledging the fact that the buildings are responsible for more than one third of total energy use, both in developed and developing countries (Cheng

140

THE GREEN BUILDING HANDBOOK

et al, 2008). With SANS 10400-XA and SANS 204 standards included in the Building Regulations and strict regulations being applied regarding competent persons involved in the building sector, South African building and construction professionals are rising to the occasion and developing excellent examples of ecological conscious buildings.

EXISTING HOMES PERFORMING TO INFERIOR STANDARDS While home owners in the local middle to upper property market, spend thousands of Rands to remodel a home to increase the market value of the property or to make it more suitable for them, they overlook the importance of including passive design strategies. These strategies have successfully been applied by commercial property owners throughout South Africa and while they reap the benefits of lower operating costs, they have harnessed the power to increase the value of the property without massive construction work. According to Nick Shore the Sustainability Director for the NSG Group’s Building Products Division, one of the world’s leading glass manufacturers, a British study showed that if all the inefficient single glazing in existing buildings across Europe was upgraded to double glazing, it could save over 100 million tonnes of CO2 per year (Shore, 2012). This highlights the problem of existing buildings performing to an inferior standard as an international phenomenon. If a home owner only change the existing single glazed doors and windows in their house to double glazed units they can


PROFILE

reduce the energy spent on regulating the temperature by as much as 50% and thereby reduce carbon dioxide emissions. Product Performance Indicators like the U-value and the Solar Heat Gain Coefficient (SHGC) is important tools professionals use to evaluate the thermal performance and make up of doors and windows, but it is foreign terminology for ordinary home owners. It remains an invaluable tool when explaining glazing performance and the building regulations to a home owner. The Product Performance Indicators was used to derive the make up of the fenestration in the renovation of an apartment in Cape Town’s Three Anchor Bay district with great results. By applying 6.38mm PVB laminated clear glass to both layers in the double glazed units, the excellent thermal performance of the apartment was not the only benefit. Other benefits included: • Draught-proofing: All round rubber seals in the frames ensure that no draughts get through. • Extra security: The use of 6.38mm PVB safety glass provides added security and increases the safety of occupants. • Acoustic insulation: The double glazed units reduce the noise from the busy Beach Road and high levels of wind noise that previously filled the apartment day and night. • Condensation reduction: With the heat reflected back into the apartment the inner

pane is much warmer resulting in virtually no condensation. Previously the apartment was cold in winter and warm in summer with constant draughts through closed windows. The owners contemplated the installation of Airconditioning to ‘correct’ the insufficient thermal performance but the installation of new windows and doors gave the clients first-hand experience of the effect that proper and correct glazing can have on the thermal performance of a home.

CONCLUSION Professionals will remain the main contributors in creating awareness when consulting clients regarding the means available to reduce carbon emissions in residential design by the use of correct glazing. Although campaigns provide a valuable source of information to the general public or residential emitters it will, like the information provided by professionals only reach a certain segment of residential emitters. Continued efforts must therefore be put forth to educate the general public through information leaflets provided with municipal accounts and possibly home energy audits done by municipal officers. It is a time consuming project to undertake but could benefit the greater cause, to reduce CO2 emissions drastically by 2050.

References •

Cheng,C., Pouffary,S., Svenningsen,N., Callaway,M., The Kyoto Protocol, The Clean development Mechanism and the Building and Construction Sector – A Report for the UNEP Sustainable Buildings and Construction Initiative, United Nations Environment Programme, Paris, France, 2008, p. 1. Shore,N. (2012). How Green is Glass. [Blog] ECO in the City Metroblogs. Available at: http://blog. worldarchitecturenews.com/?category_name=ecointhecity&paged=4 [Accessed 30 Mar. 2015].

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PERFORMANCE OF A SOLAR CHIMNEY BY VARYING DESIGN PARAMETERS

Tichaona Kumirai, Jan-Hendrik Grobler, Dr D.C.U. Conradie


8

SOLAR CHIMNEYS

T

rombe walls and solar chimneys • Height or distance (h) of the solar are not widely used or well known chimney in South Africa. A previous Green • Average inside temperature ( Ti) Building Handbook article described the expressed in K. University of Fort Hare teaching complex in East London (Stratford, 2012) that inter Performance of a for solar chimney by varying design parameters alia used a trombe system a naturally ventilated building. This article explores the Tichaona Kumirai, Researcher, Built Environment CSIR use of these passive devices further. Jan-Hendrik Grobler, DPSS CSIR Solar chimneys are elements Senior that researcher, Built Environment CSIR Drpassive D.C.U. Conradie, use solar energy to induce a buoyancy force 1 Introduction that drives airflow and naturally ventilate TrombeBuoyancy walls and refers solar to chimneys are not widely used or well known in South Africa. A the building. one of the previous Green Building Handbook article described the University of Fort Hare teaching mechanisms by which motion in fluids such complex in East London (Stratford, 2012) that inter alia used a trombe system for a naturally as air isventilated caused by naturalThis means. building. articleBuoyancy explores the use of these passive devices further. forces are induced by density differences chimneys of aretemperature passive elements due toSolar the variation of thethat use solar energy to induce a buoyancy force that drives airflow and naturally ventilate the building. Buoyancy refers to one of the mechanisms fluid: warmer and thus lighter fluid rises by which motion in fluids such asand air is caused by natural means. Buoyancy forces are coolerinduced and thus sinks. due to the variation of temperature of the fluid: warmer and bydenser densityfluid differences Figure 2: Illustration of solar chimney (Gontikaki, thus lighter rises and cooler and thus denser fluid sinks. According to fluid CIBSE (1997) the general 2010, p.3). formula that determines the flow rate According to CIBSE (1997) the general formula that determines the flow rate through a solar through a solaris:chimney is: chimney The mechanism by which solar chimney   naturally ventilates the building is illustrated in Figure 2. Solar radiation enters the chimney through the glazed part and heats up the walls. The temperature of Q= stack effect draft/draught flow rate (m2/s) the air inside the solar chimney channel A= flow area (m2) rises due to heat transfer from the walls. If C= discharge coefficient (usually taken to be the temperature difference between the from 0.65 to 0.70) air in the solar chimney channel and the 2 g= gravitational acceleration (9.81m/s ) building is high enough, then the buoyancy h= height or distance (m) forces drives the air from the interior of the Ti= average inside temperature (K) To= outside air temperature (K) building into the solar chimney channel to be exhausted at its top. The exhaust air is replaced by fresh air through openings or alternative paths in the building, and natural Figure 1: Equation (1) Stack effect in a building ventilation is accomplished. (CIBSE, 1997) Unlike mechanical     ventilation     where(1)   airflow is noticeable, since a fan is used to Figure 1: Equation (1) Stack effect in a building (CIBSE, 1997) This indicates     the   following important transfer momentum to the air to move in a aspects. following factors thataspects. certain the airflow driven by the solarflow This The indicates the following important Thedirection, following factors that determine rate (Q) available andiscan be varied designer: chimney is often not noticeable because of determine theisflow rate (Q) available andby the can be varied by the designer: the small pressure differences that lead to • Flow area (A) in m² • Flow area (A) in m² low velocities (Cengel, 2002). Because of the • Height or distance (h) of the solar chimney

144

Average inside temperature (Ti ) expressed in K.

The mechanism by which solar chimney naturally ventilates the building is illustrated in Figure 2. Solar radiation enters the chimney through the glazed part and heats up the walls.

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8

SOLAR CHIMNEYS

small buoyancy forces developed in a solar Brief description of the CFD chimney, it is very important to placed optimise the finite volume method on passive design principles, hence the use of a solar chimney to assist design of solar chimneys to ensure optimal The Navier-Stokes equations (NSE) are used and cooling.  chapter is performance. The purpose of this to describe the motion of fluids. The NSE is Methodology based on the principle of the conservation to discuss the performance of2an example To quantify the effect of the abovementioned objectives, a numerica of momentum, but was the continuity equation shown he solar chimney by varying (mathematical the design modelling) methodology used. The simulations performed commercial Computational Fluid (CFD) parameters and examining their effects with on the(based on the conservation ofDynamics mass) and the code StarCCM+ that utilises the finite volume method in its computations. the interior ventilation performance. energy equation (based on the conservation   of energy) areCFD usually included. The 2.1 Brief description of the finite volume method and of fluids. Analysis objectives The Navier-Stokesconservation equations (NSE)ofaremass, used tomomentum describe the motion on the principle of the of momentum, but (2), the (3) continuity equ â&#x20AC;˘ The effect of chimney wall based temperature energy areconservation given below by equations on the conservation of mass) and the energy equation (based on the con on interior ventilation performance. (4), respectively. The of formulations use and ener energy) are usuallyand included. The conservation mass, momentum below on by equations (2), (3) and (4), respectively. The use index not â&#x20AC;˘ The effect of floor grille width the index notation, where i â&#x201A;Ź {1, 2, formulations 3}; j â&#x201A;Ź {1, 2, 3}. i Ďľ {1, 2, 3}; j Ďľ {1, 2, 3}. interior ventilation performance.   â&#x20AC;˘ The effect of chimney height on the đ?&#x153;&#x2022;đ?&#x153;&#x2022;đ?&#x153;&#x2022;đ?&#x153;&#x2022; đ?&#x153;&#x2022;đ?&#x153;&#x2022; + đ?&#x153;&#x152;đ?&#x153;&#x152;đ?&#x2018;˘đ?&#x2018;˘! = 0                                                                                                           (2) interior ventilation performance. đ?&#x153;&#x2022;đ?&#x153;&#x2022;đ?&#x153;&#x2022;đ?&#x153;&#x2022; đ?&#x153;&#x2022;đ?&#x153;&#x2022;đ?&#x2018;Ľđ?&#x2018;Ľ! â&#x20AC;˘ The effect of chimney inlet position on đ?&#x153;&#x2022;đ?&#x153;&#x2022; đ?&#x153;&#x2022;đ?&#x153;&#x2022; the interior ventilation performance. placed on passive design of ađ?&#x153;?đ?&#x153;?!" solar=chimney to assist in ventilatio đ?&#x153;&#x152;đ?&#x153;&#x152;đ?&#x2018;˘đ?&#x2018;˘ đ?&#x153;&#x152;đ?&#x153;&#x152;đ?&#x2018;˘đ?&#x2018;˘hence đ?&#x2018;?đ?&#x2018;?đ?&#x203A;żđ?&#x203A;żuse 0                                                                       (3) ! +principles, ! đ?&#x2018;˘đ?&#x2018;˘! +the !" â&#x2C6;&#x2019; đ?&#x153;&#x2022;đ?&#x153;&#x2022;đ?&#x2018;Ľđ?&#x2018;Ľ đ?&#x153;&#x2022;đ?&#x153;&#x2022;đ?&#x153;&#x2022;đ?&#x153;&#x2022; and cooling. ! â&#x20AC;˘ The effect of chimney inlet area on the   interior ventilation performance. 2 Methodology đ?&#x153;&#x2022;đ?&#x153;&#x2022; đ?&#x153;&#x2022;đ?&#x153;&#x2022;

To quantify the effect of the abovementioned objectives, a numerical simulatio (4) đ?&#x153;&#x152;đ?&#x153;&#x152;đ?&#x2018;&#x2019;đ?&#x2018;&#x2019;! + methodology đ?&#x153;&#x152;đ?&#x153;&#x152;đ?&#x2018;˘đ?&#x2018;˘! đ?&#x2018;&#x2019;đ?&#x2018;&#x2019;! + was đ?&#x2018;˘đ?&#x2018;˘! đ?&#x2018;?đ?&#x2018;? used. + đ?&#x2018;&#x17E;đ?&#x2018;&#x17E;! The â&#x2C6;&#x2019; đ?&#x2018;˘đ?&#x2018;˘simulations ! đ?&#x153;?đ?&#x153;?!" = 0                                                        (mathematical shown here were a đ?&#x153;&#x2022;đ?&#x153;&#x2022;đ?&#x153;&#x2022;đ?&#x153;&#x2022; modelling) đ?&#x153;&#x2022;đ?&#x153;&#x2022;đ?&#x2018;Ľđ?&#x2018;Ľ! performed with the commercial Computational Fluid Dynamics (CFD) code Star-CCM+. Sta CCM+ that utilises the finite volume method in its computations.

Description of bio-    can be solved analytically in some cases, but have no kn composite building These equations 2.1

Brief description of the CFD finite volume method

2.2

CFD Solver settings

solution.These The finite volume method frequently used to transform th The solar chimney described inanalytical this chapter beistosolved The Navier-Stokes equations equations (NSE)can are used describe analytically the motion of fluids. The NSE their partial based differential form toof algebraic equations, which be solved numeric on the principle the conservation of momentum, but can the continuity equation (base forms part of an experimental aid building the in some cases, but have no known general of a computer. on the conservation of mass) and the energy equation (based on the conservation energy) are usually included. The conservation of mass, momentum and energy are give CSIR is undertaking to test the feasibilitybelow of by analytical solution. The finite volume equations (2), (3) and (4), respectively. The formulations use index notation, whe The term â&#x20AC;&#x153;finite non-overlapping volumes surrounding a numbe i Ďľ {1, volumeâ&#x20AC;? 2, 3}; j Ďľ {1, refers 2, 3}.is to constructing a net zero building, i.e. energy, method frequently used to transform the node points  where values are calculated. The divergence theorem is used to đ?&#x153;&#x2022;đ?&#x153;&#x2022; example, water, waste, emissions, and volume biodiversity fromintegrals. theirđ?&#x153;&#x2022;đ?&#x153;&#x2022;đ?&#x153;&#x2022;đ?&#x153;&#x2022;partial differential form to theorem integrals toNSE surface For if the divergence đ?&#x153;&#x152;đ?&#x153;&#x152;đ?&#x2018;˘đ?&#x2018;˘! = 0                                                                                                                                            (2 + đ?&#x153;&#x2022;đ?&#x153;&#x2022;đ?&#x153;&#x2022;đ?&#x153;&#x2022; đ?&#x153;&#x2022;đ?&#x153;&#x2022;đ?&#x2018;Ľđ?&#x2018;Ľ! (2), it takes the following form: loss. To achieve this outcomeequation significant algebraic equations, which can be solved   đ?&#x153;&#x2022;đ?&#x153;&#x2022; the aid of a computer. đ?&#x153;&#x2022;đ?&#x153;&#x2022; emphasis is placed on passive design numerically with đ?&#x153;&#x152;đ?&#x153;&#x152;đ?&#x2018;˘đ?&#x2018;˘! + đ?&#x153;&#x152;đ?&#x153;&#x152;đ?&#x2018;˘đ?&#x2018;˘! đ?&#x2018;˘đ?&#x2018;˘! + đ?&#x2018;?đ?&#x2018;?đ?&#x203A;żđ?&#x203A;ż!" â&#x2C6;&#x2019; đ?&#x153;?đ?&#x153;?!" = 0                                                                                                        (3 đ?&#x153;&#x2022;đ?&#x153;&#x2022; đ?&#x153;&#x2022;đ?&#x153;&#x2022;đ?&#x2018;Ľđ?&#x2018;Ľ! + đ?&#x153;&#x2022;đ?&#x153;&#x2022;đ?&#x153;&#x2022;đ?&#x153;&#x2022; + đ?&#x2018;?đ?&#x2018;?đ?&#x203A;żđ?&#x203A;ż â&#x2C6;&#x2019; nonđ?&#x153;?đ?&#x153;?!" đ?&#x2018;&#x203A;đ?&#x2018;&#x203A;! đ?&#x2018;&#x2018;đ?&#x2018;&#x2018;đ?&#x2018;&#x2018;đ?&#x2018;&#x2018; = 0   principles, hence the use of a solar chimney đ?&#x153;&#x152;đ?&#x153;&#x152;đ?&#x153;&#x152;đ?&#x153;&#x152;! đ?&#x2018;&#x2018;đ?&#x2018;&#x2018;đ?&#x2018;&#x2018;đ?&#x2018;&#x2018; The termđ?&#x153;&#x152;đ?&#x153;&#x152;đ?&#x153;&#x152;đ?&#x153;&#x152;â&#x20AC;&#x153;finite volumeâ&#x20AC;? refers ! đ?&#x2018;˘đ?&#x2018;˘! đ?&#x2018;&#x203A;đ?&#x2018;&#x203A;! đ?&#x2018;&#x2018;đ?&#x2018;&#x2018;đ?&#x2018;&#x2018;đ?&#x2018;&#x2018; !" đ?&#x2018;&#x203A;đ?&#x2018;&#x203A;! đ?&#x2018;&#x2018;đ?&#x2018;&#x2018;đ?&#x2018;&#x2018;đ?&#x2018;&#x2018;to đ?&#x153;&#x2022;đ?&#x153;&#x2022;đ?&#x153;&#x2022;đ?&#x153;&#x2022; ! ! ! ! đ?&#x153;&#x2022;đ?&#x153;&#x2022; đ?&#x153;&#x2022;đ?&#x153;&#x2022; to assist in ventilation and cooling. overlapping volumes surrounding a number đ?&#x153;&#x152;đ?&#x153;&#x152;đ?&#x2018;&#x2019;đ?&#x2018;&#x2019;! + đ?&#x153;&#x152;đ?&#x153;&#x152;đ?&#x2018;˘đ?&#x2018;˘! đ?&#x2018;&#x2019;đ?&#x2018;&#x2019;! + đ?&#x2018;˘đ?&#x2018;˘! đ?&#x2018;?đ?&#x2018;? + đ?&#x2018;&#x17E;đ?&#x2018;&#x17E;! â&#x2C6;&#x2019; đ?&#x2018;˘đ?&#x2018;˘! đ?&#x153;?đ?&#x153;?!" = 0                                                                                          (4 đ?&#x153;&#x2022;đ?&#x153;&#x2022;đ?&#x2018;Ľđ?&#x2018;Ľ! đ?&#x153;&#x2022;đ?&#x153;&#x2022;đ?&#x153;&#x2022;đ?&#x153;&#x2022; discrete node points where values are Once in this   form, of a set of algebraic equations can be obtained that describe h variables change in each volume as divergence aanalytically functioninofsome time. A detailed discussion of These equations can be solved cases, butishave no known gener calculated. The theorem used analytical solution. The finite volume number method is of frequently used have to transform NSE fro is not included here because a large methods beenthedevelop partial formthe to for algebraic equations, which can solved numerically with th Methodology todifferential convert volume integrals tobe surface adaptions totheir this basic technique specific purposes. These include different aid of a computer. properties at faces; performing Reynolds-averaging to To quantify the effect of approximate the aboveflow integrals. Fortheexample, if the divergence The â&#x20AC;&#x153;finite volumeâ&#x20AC;? to non-overlapping volumes surrounding number of discre of term turbulence modelling; and modifications to allow athe modelling mentioned objectives, a introduction numerical theorem isrefers applied to equation (2), it takes multiphase node flow.points where values are calculated. The divergence theorem is used to convert th volume integrals to surface integrals. For example, if the divergence theorem is applied simulation (mathematical modelling) the following form: equation (2), it takes the following form:   Solver settings CFD methodology was used. The 2.2 simulations đ?&#x153;&#x2022;đ?&#x153;&#x2022; Figure 3 is an illustration the bio-composite building. two solar chimn đ?&#x2018;&#x2018;đ?&#x2018;&#x2018;đ?&#x2018;&#x2018;đ?&#x2018;&#x2018; + đ?&#x153;&#x152;đ?&#x153;&#x152;đ?&#x153;&#x152;đ?&#x153;&#x152;! đ?&#x2018;˘đ?&#x2018;˘! đ?&#x2018;&#x203A;đ?&#x2018;&#x203A;! đ?&#x2018;&#x2018;đ?&#x2018;&#x2018;đ?&#x2018;&#x2018;đ?&#x2018;&#x2018; + đ?&#x2018;?đ?&#x2018;?đ?&#x203A;żđ?&#x203A;ż!" đ?&#x2018;&#x203A;đ?&#x2018;&#x203A;! đ?&#x2018;&#x2018;đ?&#x2018;&#x2018;đ?&#x2018;&#x2018;đ?&#x2018;&#x2018; â&#x2C6;&#x2019; Theđ?&#x153;?đ?&#x153;?!" đ?&#x2018;&#x203A;đ?&#x2018;&#x203A; shown here were all performed with the đ?&#x153;&#x2022;đ?&#x153;&#x2022;đ?&#x153;&#x2022;đ?&#x153;&#x2022; ! đ?&#x153;&#x152;đ?&#x153;&#x152;đ?&#x153;&#x152;đ?&#x153;&#x152;! of ! đ?&#x2018;&#x2018;đ?&#x2018;&#x2018;đ?&#x2018;&#x2018;đ?&#x2018;&#x2018; = 0                                    (5 clearly seen. ! ! ! (5) commercial Computational Fluid Dynamics â&#x20AC;ş Once in this form, a set of algebraic equations can be obtained that describe how the flo variables change in each volume as a function of time. A detailed discussion of this proces (CFD) code Star-CCM+. Star-CCM+ that is not included here because a large number of methods have been developed to mak utilises the finite volume method in adaptions its to this basic technique for specific purposes. These include different methods approximate flow properties at the faces; performing Reynolds-averaging to enable th computations. Once in thismodelling; form, a set of algebraic equations introduction of turbulence and modifications to allow the modelling of inter al multiphase flow. can be obtained that describe how the

Figure 3 is an illustration of the bio-composite building. The two solar chimneys can b clearly seen. â&#x20AC;ş

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145


8

SOLAR CHIMNEYS

flow variables change in each volume as a function of time. A detailed discussion of this process is not included here because a large number of methods have been developed to make adaptions to this basic technique for specific purposes. These include different methods to approximate flow properties at the faces; performing Reynolds-averaging to enable the introduction of turbulence modelling; and modifications to allow the modelling of inter alia multiphase flow.

CFD Solver settings

Figure 3 is an illustration of the biocomposite building. The two solar chimneys can be clearly seen. For simulation purposes the flow was assumed to have reached a steady state and approximately 650 000 volumes (Figure 4) also referred to as cells were used in each model. The air was assumed to behave as an ideal gas. Turbulence was modelled using the CFD k-ε turbulence model. Since the flow is driven by buoyancy effects, density gradients were important and therefore the “coupled solver”-option was selected as opposed to the standard “segregated solver”-option.

Figure 4: Computational domain of approximately volumes

Simulation strategy

The simulation strategy used is described in Table one. The right hand of Table one shows the design parameters that were investigated. The left hand shows the results of the volume flow rates for both chimneys. Simulation number 569 was used as a basis for comparison; therefore the results of simulation number 569 appear in the graphs of results (Figures 4-8).

Figure 3: An artist’s impression of the completed bio-composite building.

146

THE GREEN BUILDING HANDBOOK


SOLAR CHIMNEYS

8

567 0.49

0.41

0.32

0.50

0.54

0.49

0.41

0.32

Chimney 2

1.00

1.09

0.99

0.83

0.63

70

70

80

70

55

40

Total Wall flow rate Temperature (°C)

300

500

400

300

300

300

300

bottom

bottom

bottom

bottom

bottom

bottom

bottom

0.6

0.6

0.6

0.6

0.6

0.6

0.6

1

0

0

0

0

0

0

Summary of Results: Volume Flow Rate (m³/s) Design Parameters

568 0.54

70

Simulation Chimney Number 1

569 0.50 0.99

Chimney Chimney inlet Area Height (m²) Above Roof (m)

570

1.18

Floor Grill Chimney Width Inlet (mm) Position

571 0.50

0

0.59

0

0.50

0

0.59

chimney inlet 0.6 at the top

0

572

0.9

573

1.2

2

bottom

0.6

300

bottom

bottom

300

300

70

300

70

70

1.35

70

0.67

1.19

0

0.67

simulation failed to converge

1.25

0.6

2

574

0.59

bottom

1.2

300

0.62

3 x 300 grill

bottom

70

0.60

70

500

0.51

576

0.62

1.03

40

0.16

577

0.52

1.12

0.35

578 0.52

0.56

575

634 0.56

chimney inlet 0.6 halfway

635

Table 1: Simulation strategy

147

THE GREEN BUILDING HANDBOOK


SOLAR CHIMNEYS

Results and discussion:Effect of chimney wall temperature on chimney air flow rate

8

Figure 5 shows the inside chimney wall temperature on the horizontal axis and chimney air floor rate on the vertical axis. Figure 4 indicates that there is a linear relationship between the chimney wall temperature and chimney air flow rate. Increasing chimney wall temperature increases chimney air flow rate. Therefore a high chimney wall temperature is desired for a maximum building interior air change rate (See Figure 1, Equation 1). A high chimney wall temperature can be achieved by painting the chimney walls with high solar absorptance paints such as matt black paint. It is highly recommended that the absorbing solar chimney walls be constructed from high thermal mass building materials such as brick and concrete. This ensures a substantial sensible heat storage in the walls which can drive air flow in the chimney for longer periods

during overcast periods and prolong the effectiveness after sunset.

Effect of floor grille width on chimney air flow rate

Figure 6 illustrates the air inlet floor grille width on the horizontal axis and chimney air floor rate on the vertical axis. Note that simulation 634 in Figure 6 is a combination of three separate air inlet floor grilles with a grille width of 300 mm each, which adds up to a 900 mm air inlet grille width (See Figure 7). Figure 6 indicates that increasing the grille width from 300 mm to 400 mm increases the chimney air flow rate. Figure 6 also indicates, somewhat counterintuitively, that increasing the grille width from 400 mm to 500 mm begins to reduce the chimney air flow rate. These results indicate that there is an optimum air inlet grille width beyond which a poorer solar chimney performance will result. This result can also be interpreted as, beyond 400 mm air inlet grille width, the buoyancy effect of the solar chimney will be cancelled. This means that natural

Figure 5: Effect of chimney wall temperature on chimney air flow rate (Refer to Table 1 for related design parameters for given simulation numbers)

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SOLAR CHIMNEYS

Figure 6: Effect of floor grille width on chimney air flow rate (Refer to Table 1 for related design parameters for given simulation numbers)

cross ventilation from windows and doors will reduce the performance of the solar chimney (this effect was not evaluated in any of our simulations). If the solar chimney is to provide ventilation on wind still days, the doors and windows should be shut. However if it is a windy day the user can decide to rather use windows to provide natural ventilation, because the solar chimney is not necessary.

Effect of chimney height on chimney air flow rate

Figure 8 illustrates the height of the chimney above the roof level on the horizontal axis and chimney air floor rate in the vertical axis. Figure 8 indicates that there is a linear relationship between height of chimney above roof and chimney air flow rate. Increasing height of chimney above roof increases chimney air flow rate. Although not specifically addressed in this chapter it is important to note that the chimney should be high enough to ensure that the Neutral Pressure Level (NPL) in the chimney is well above the building to avoid the possibility that hot air enters the building.

Effect of chimney inlet area on chimney air flow rate Figure 7: Position of 3 x 300 mm floor grilles coloured in purple

Figure 9 indicates the chimney inlet area on the horizontal axis and chimney air flow rate on the vertical axis. Figure 9 indicates that there is a big increase of 0.22 m続/s in

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CHIEFTON Chiefton Facilities Management has left a lasting impression on the capabilities of small enterprises through its delivery methods and astute team of professionals. Due to the stigma associated with small black owned companies relating to non-delivery and the assumed inabilities to perform due to inadequate resources, small brands like Chiefton have been overlooked, but, now over the past 10 years, Chiefton has managed to change this mindset and has proven to be at the forfront of strategic thinking, solutions and innovation. It is now a brand that is well recognised for it’s reliablility and has moved itself beyond its key performance areas, progressing projects to completion despite the client’s budget constraints and process deficiencies. We do more with less! The bottom line is, “We complete projects!” That’s our role. We find solutions and we are astute troubleshooters. We have seen tremendous growth due to our commitment, dedication and moral standings with our clients. Our ability to package solutions and coordinate resources to meet project demands, has been our key success factor. It is not all about making money, its about pleasing our client, first. This basic principle has been forgotten by many companies including corporates, and Chiefton takes advantage of this – best price, best advise! Chiefton has become a sort-after Strategic Advisor in the field of Facilities Management and Infrastrusture Operations in general. We have served clients across the industry and completed some flagship projects that we are proud of:

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SOLAR CHIMNEYS

Figure 8: Effect of chimney height on chimney air flow rate (Refer to Table 1 for related design parameters for given simulation numbers)

Figure 9: Effect of chimney inlet area on chimney air flow rate (Refer to Table 1 for related design parameters for given simulation numbers)

chimney air flow rate when increasing the chimney inlet area from 0.6 m² to 0.9 m². However a further increase of the chimney inlet area from 0.9 m² to 1.2 m² results in a very small increase of 0.04 m³/ s in the

chimney air volume flow rate. Once again this indicates that there is an optimum chimney inlet area beyond which no further improvements in chimney air volume flow rate are realised.

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Results for air flow pattern

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The results of Figures 5 to 9 are based on air change rate as an indicator for ventilation performance. However for good ventilation practise, it is not enough to achieve just the prescribed air change rate of fresh outdoor air. An adequate air distribution pattern is also required for replacing all the air in the room, otherwise there may be overventilated zones and others where the air is stagnant (Meâ&#x20AC;&#x2122;ndez et al., 2008). Meâ&#x20AC;&#x2122;ndez, et al., (2008) goes further to describe and explain mean age of air as another ventilation performance indicator. They

defined the mean age of air at a point as the mean time that the air particles contained in a differential volume around the point have stayed inside the room. The freshest air (least time in space) will be found at outdoor air inlets, while the oldest air can be found at any other point, not necessarily at the outlets. For instance, if there is a stagnation region or a recirculation region, the mean age of air will be high in these regions and the ventilation will be poor. The right side of Figure 10 is entirely blue. This shows that there is little or no air movement on the right side of the building.

Figure 10: Air velocity distribution within the ventilated space for one floor inlet grill at the middle and chimney inlet located at the bottom

Figure 11: Air velocity distribution within the ventilated space for 3 floor inlet grills and chimney inlet located at the bottom

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This means that the mean age of air is high on the right side of building that will lead to poor air quality. This shows that the initial idea of one middle inlet floor grill would cause poor air quality on the right side of the building. A simulation which included three inlet floor grills as illustrated in Figure 7 was done and the air velocity distribution captured in Figure 11. Figure 11 shows that there is air movement on the left, middle and right sections of the building. Spreading the air inlet floor grills therefore promotes a better distribution of air flow that leads to good indoor air quality.

Conclusions

Currently solar chimneys are not widely used in South Africa for a variety of reasons. This chapter quantified the effect of the various design parameters on the efficiency of the air flow. The study indicated that all the design parameters investigated affect

SOLAR CHIMNEYS

the ventilation performance of the solar chimney. It was also discovered that there is an optimum beyond which no significant improvement in air flow is realised or even a reduction in efficiency might occur. The precedent study for the University of Fort Hare teaching complex in East London (Stratford, 2012) and the simulations ran in this study clearly prove that buoyancy driven ventilation systems such as Trombe walls and solar chimneys do work well if they are designed properly. Furthermore they perform well in a hot and sunny country such as South Africa that provides sufficient temperature differentials to drive the chimney. Buoyancy driven ventilation systems continue to function in wind still conditions that are often found in places such as Pretoria. Over and above sufficient air changes per hour the distributed placement of floor inlets will ensure a air distribution and good air quality.

References • • •

• •

Cengel, Y.A., 2008. Introduction to thermodynamics and heat transfer. 2nd ed. Reno, Nevada, USA: McGraw-Hill. Chartered Institution of Building Services Engineers (CIBSE), 1997. CIBSE applications manual AM10 natural ventilation in non-domestic buildings. London: CIBSE. Gontikaki, M., 2010. Optimisation of a solar chimney to enhance natural ventilation and heat harvesting in a multi-storey office building. March. Technical University of Eindhoven. Available at: http://www.bwk.tue.nl/bps/hensen/team/past/master/Gontikaki_2010.pdf [Accessed 3.04.2014]. Mendez, C., San Jose J.F., Villafruela, J.M. and Castro, F., 2008. Optimization of a hospital room by means of CFD for more efficient ventilation. Energy and Buildings, 40(2008), pp.849–854. Stratford, A. 2012. University of Fort Hare: new Auditoria and Teaching Complex: East London Campus. In Green building Handbook, Volume 4, pp. 157-163.

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While the   current   emphasis   on   green   building   with   all   its   technical solu)ons   in   crea)ng   green   buildings,   is   admirable,   the   key   is   to   change PROFILE the  lifestyle  of  all  humans. This   change   needs   to   curb   the   environmentally   nega)ve   impact   of   the predicted  doubling  of  the  world  popula)on  over  the  next  half  millennium. AVNA   proposes   a   new   form   of   mul)-­‐use   tower   block:   a   self-­‐contained ver)cal  village.  Apart  from  the  exchange  of  goods  and  services,  occupants would  have  no  need  to  leave  their  village.

avna

AVNA ARCHITECTS architects

Groups of  towers  (villages)  are  to  be  erected  in  areas  where  the  natural environment   has   been   permanently   damaged.   Villages   are interconnected  electronically  and  by  mass-­‐transport  media  at  base  level.

Technical features:   The  physical  features   of  towers   hat  render   it  self-­‐sustainable   includes: AVNA architects and green-building designers sunscreens of photovoltaic panels, • tRotating is involved in experimental design that searches following the sun. 1 Rota)ng  sunscreens  of  photovoltaic  panels,  following  the  sun. for a new order in the built environment • Rotating windscreens enabling satisfactory 2 Rota)ng  windscreens  enabling  sa)sfactory  outdoor  life  on  the  various  piazza  levels  between  towers. thereby laying the groundwork forto  atwo   full  outdoor life fion various piazza levels A   central   energy-­‐genera)ng   device   consis)ng   height   water-­‐ lled  the tubes.   A   looped   drive-­‐belt, 3and constitution of a new, modern andby  sustainable between towers. rota)ng   through   both   and   powered   aAached,   inverted   cup-­‐shaped   air   collectors,   travelling   upwards   in   a stream  While of  air  that   nters  at  the   base  of  one   the  tubes.  •Having   eleased  the   air,  it  is  then  subjected  to  gdevice ravity society. theecurrent emphasis onof  green A rcentral energy-generating in  the  alternate  tube.  Energy  gained  from  decelera)ng  people  carrier  liFs  are  also  used  to  boost  this  system. consisting of two full height water-filled building with all its technical solutions in 4 Methane  is  produced  from  organic  waste  in  the  basement  of  each  building.  This  is  then  used  for  steam-­‐based creating buildings, is admirable, keyor  hea)ng   tubes. looped drive-belt, rotating through energy  ggreen enera)on   and  a  central   supply  for  cthe ooking   ,  aFer  A cleaning. change the lifestyle of all humans. This both and powered by attached, inverted In  dry  climates  a  centrally  placed  evapora)ve  cooling  tower  creates  a  cool  airstream,  which  can  be  used  by 5is to adjacent   accommoda)on   let  environmentally cool   air   into   the   units.   The  cup-shaped hot   air   is   then   on   the   opposite  upwards side   at change needs to curb to   the airreleased   collectors, travelling higher  level. negative impact of the predicted doubling in a stream of air that enters at the base of 6 At  high  level,  the  helical  wind  generator  joins  the  power  genera)on  combina)on. of the world population over the next half one of the tubes. Having released the air, it 7 Rainwater  is  harvested  in  a  subterranean  reservoir  and  services  the  buildings  potable  water  needs.  Recycled millennium. AVNA proposes a new form of is then subjected to gravity in the alternate water  is  used  for  farming  ac)vi)es  on  the  piazza  levels. towercooling   block: system   a self-contained tube. The drive isduring   connected an electricity A   geothermal   assists   the   vertical hybrid   of   technologies,   especially   more   to humid   weather 8multi-use condi)ons. village. Apart from the exchange of goods and generator. Energy gained from decelerating services, occupants would have no need to people carrier lifts are also used to boost this Combined  with  other  energy-­‐efficient  and  sustainable  systems,  the  tower  is  largely  turned  into  a  net-­‐energy leave their village. Groups of towers (villages) system. producer,  feeding  excess  into  a  na)onal  grid. are to be erected in areas where the natural • Methane is produced from organic waste in the basement of each building. This is then environment has been permanently damaged. Villages are interconnected electronically and used for steam-based energy generation by mass-transport media at base level and a central supply for cooking or heating, after cleaning. • In dry climates a centrally placed evaporative Technical features cooling tower creates a cool airstream, which The physical features of towers that render it self-sustainable includes: can be used by adjacent accommodation to

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PROFILE

let cool air into the units. The hot air is then released on the opposite side at higher level. • At high level, the helical wind generator joins the power generation combination. • Rainwater is harvested in a subterranean reservoir and services the buildings potable water needs. Recycled water is used for farming activities on the piazza levels • A geothermal cooling system assists the hybrid of technologies, especially during more humid weather conditions. Combined with other energy-efficient and sustainable systems, the tower is largely turned into a net-energy producer, feeding excess into a national grid.

Farming / food security Some piazza levels act as village squares and allows for entertainment, education, physical Social life training, socialising and relaxation. On other Each  tower  is  dedicated  to  a  different  level  or  form  of levels various grown,age   supplementing educa;on,   ranging  crops from  are younger   groups   to the variety by adult   bartering anyand   surplus with dedicated   schooling,   educa;on   correc;ve educa;on   for  problem   individuals. neighbouring communities. From  early  on,  individuals  learn  to  find  a  place  in  the Social life tower  society  based  on  a  voca;on,  while  balancing  it Each tower is dedicated to a different level or out   with   volunteer   work   in   other   fields,   including form ofand   education, ranging elderly-­‐care   assis;ng  in   farming.from younger age

Technical attempts at greener buildings will not create a greener society. Social entrepreneurs must create a new social order. Architects’ contribution would be in interpreting social systems and to design a place enabling the future fundamentals. The design illustrated here is such an attempt. It remains to be seen who will take the lead in this process – an individual or a collective? Precedent for a strong architectural response to a changing society and promoting further change, is found in the architectural international movement of the 1960s. The new champions of change will have to create a fundamentally new way of life, comparable in size but not content, to the Industrial Revolution. However, henceforth social intervention and empathy for human life and the earth alike will be the point of reference: an international revolution of mind and spirit. Farming /  could food  sact ecurity Architecture as catalyst through a Some  piazza  levels  act  as  village  squares  and central movement based in the virtual realm. allows  for  entertainment,  educa;on,  physical Contributions and and   thoughts must freely training,   socialising   relaxa;on.   On  be other shared toward sustainable future for thethe earth, various   crops  aare   grown,   supplemen;ng   with humans be surplus   a relatively small variety   by   supposed bartering   to any   with neighbouring   communi;es. part of the ecosystem.

groups to dedicated schooling, adult education

A culture   mutual   understanding   is   thus   and of   corrective education for cul;vated problem with  individuals. a   focus   on   direct   contact.   Spaces From interpersonal   early on, individuals learn to are   fidesigned   to   enable   and   promote   nd a place and meaning in the strong   tower social society awareness  and  care.  Reward  is  not  only  monetary,  but based on a vocation, while balancing it out includes  goods  or  services.

with volunteer work in other fields, including elderly-care and assisting in farming. A culture of mutual understanding is thus cultivated with a focus on direct interpersonal contact across all generations and other groups. A levy  on  social  involvement  is  linked  individually  and used  Spaces as   further   of   bartering.   Exchange   done   in areform   designed to enable andis   promote kind  strong and   creates   jobs   with   a   realis;c   for  Reward persons is social awareness andvalue   care. of  all  not abili;es. only monetary, but includes exchange for goods or services. A levy on social involvement is linked individually and used as further form of bartering. Exchange is done in kind and creates jobs with a realistic value for persons of all abilities. THE GREEN BUILDING HANDBOOK

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PROFILE

AQUAPOL CASE STUDY Kyalami Castle, Midrand

The Kyalami Castle Castle Kyalami was built in 1992 by Greek millionaire and architect Demos Dinopoulos. Located in the northern Johannesburg suburb of Kyalami adjacent to the Kyalami Race Track, the 5900 m² castle is set on 22 acres of brushland. It has an Arthurian style and was built with a spa, 24 suites, a luxury hotel, a restaurant, a conference centre and its own helipad. The Castle was a recommended and popular tourist attraction until 2006 when it was purchased by a private company.

The problem Numerous spaces had wet, musty smells and evidence of wall moisture.

Client’s requirement To dry out the affected walls without interfering with the integrity of the masonry. This had to be achieved by avoiding, if possible, the disruptive installation of a vertical membrane or an outside drainage system.

What was done We inspected the site and found large areas of rising damp which were evident on the inside walls where paint was found to be bubbling and flaking, plaster was cracking and visible salts had crystalized. Also on the outside brick

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façade there were clear “tide marks” up to 1.2 meters indicating the presence of rising damp. Other sources of wall moisture were also identified as coming from leaking pipes and gutters as well as from condensation in some areas where poor ventilation existed.

The project - Installation In February 2013 Aquapol South Africa was contracted to dry out the rising damp


PROFILE

Inspections The first inspection was carried out 5 months after installation. A 51% moisture reduction was measured in this short space of time. The second inspection was conducted one year

after installation. Despite very heavy rainfalls during the summer season the walls remained dry. The diagram illustrates the overall reductions at the various drill points. The only anomaly being Measuring Point M5, located adjacent to a bathroom which was later found to have leaking pipes.

The client’s feedback The client initiated this unsolicited feedback below:

I.H. and I recently did an assessment of the damp-proofing of the (Kyalami) Castle. As you know, the results are remarkable. We are now in the process of cleaning the walls, where they were stained. I.H. and I are of the opinion that there is a lot of potential for your product, and, with I.H. as an engineer and myself as an architect, we have many contacts in the construction industry. We would like to get the Aquapol system “marketed” via civil engineers to the end-user or property owner as a business venture. -T.P.

component of wall moisture and work commenced in the same month. Measuring out the area that needed to be dried out the correct locations were determined to install the 3 Aquapol devices to give maximum coverage – the entire Castle. Once installed, using the recognized DARR method (the most accurate method for determining the absolute moisture content of construction materials), seven points were isolated to drill into the walls for the purpose of extracting brick samples. The moisture of these samples was recorded using a precision measuring instrument. From Figure 1 below it can be seen that the brick samples were wet at the time of installation, indicating that the walls themselves were wet internally, not just superficially.

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THE ROLE OF ACOUSTICS IN THE CONTEXT OF GREEN BUILDINGS

Coralie van Reenen


ACOUSTICS AND GREEN BUILDING

9

T

he Green Building Council of South Africa (GBCSA) recognises good acoustics as a point of merit under the Indoor Environment Quality category of its rating tools. While good acoustics definitely has its place in design, what is its role in the greening of buildings? The concept of green building is most commonly thought of as a drive to decrease the carbon footprint of development and minimise the depletion of natural resources. However, this is only part of the motive. While we advocate saving the planet, in truth we are striving to save ourselves, mankind. The Green Building Council makes the statement that “building green is an opportunity to use resources efficiently and address climate change while creating healthier and more productive environments for people to live and work in” (Green Building Council South Africa, n.d.). In other words, building green is as much about the sustainability of the environment as it is about supporting the sustainability of people and businesses. What would be the point of building highlyrated green buildings if they were terrible spaces to occupy?

Indoor environment quality

The GBCSA, as well as other green building councils around the world, factor Indoor Environment Quality (IEQ) into their rating systems in pursuit of this human aspect of development. The term “sick building syndrome” (SBS) has long been used to describe a range of negative health effects experienced by building occupants that can be associated with time spent in a poor building environment. The World Health Organisation recognised the adverse health effects of ‘sick buildings’ as early as 1982 (World Health Organization, 1982). Symptoms may include chest tightness and difficulty with breathing, eye irritation, dry throat, headaches, tiredness, irritation

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or concentration difficulties and even fever (Bluyssen, 2009). While this condition is primarily related to the air quality in a building, it is also associated with other aspects of the indoor environment, such as poor lighting, thermal discomfort and noise (Bluyssen, 2009). The impact of a poor indoor environment extends beyond the direct physiological and psychological effects on the occupants, influencing productivity. Research has shown that the building itself can influence productivity by up to 17% (ClementsCroome, 2006), with associated economic impacts. Since the green movement is as much about creating healthy, productive environments as it is about resource efficiency, the IEQ category in the Green Star rating system can be justified. More specifically, though, the reason for including acoustics needs to be understood and justified. For this, it is important to first understand the nature of sound and the definition of noise.

Sound and noise

Sound is energy in the form of a wave of vibrating particles with an amplitude and frequency. The amplitude of the wave determines the loudness, described as a sound level in deciBels [dB]. The frequency can be described as the pitch, measured in Hertz [Hz]. The range of human hearing is 0 dB to about 130 dB at frequencies between 30 Hz and 20 kHz. Hearing damage can occur due to exposure to certain frequencies, prolonged exposure to sound above 90 dB or short-term exposure to sound above 120 dB. However, these thresholds do not necessarily define noise. Rather noise is defined as unwanted sound and is very subjective. Noise can have two basic kinds of effects on humans. Firstly, it can have auditory effects that lead to hearing damage, as


9

mentioned above. Secondly, and more importantly for this discussion, are the nonauditory effects. This cannot be measured empirically and results from noise that is not necessarily excessively loud but rather noise that interferes with activities or disturbs attitudes. Non-auditory effects include performance effects, such as disrupted work or rest, and physiological effects, such as increased heart rate and blood pressure (Canadian Centre for Occupational Health and Safety, 2007). The World Health Organization (WHO) lists cognitive impairment, annoyance and cardiovascular disease amongst the effects of noise on people (World Health Organization, 2011). From this it is easy to see how noise influences health, happiness and productivity. In non-industrial buildings, the source of this kind of noise is typically building services (such as noisy ventilation systems), traffic, talking, alarms, or media. Recommended ambient noise levels for various types of spaces are listed in the WHO Guidelines for community noise (Berglund, et al., 1999) and SANS 10103. The measurement and rating of environmental noise with respect to annoyance and speech communication

ACOUSTICS AND GREEN BUILDING

(South African National Standards, 2008), providing a useful reference for design. In working and living environments,

Figure 1: Graphic representation of reverberation time

the common criteria for good acoustics are speech intelligibility, speech privacy and non-distractibility. One of the most important aspects of acoustics to be controlled in order to achieve these requirements is reverberation. This refers to the amount of time it takes for a sound to die down by 60 dB. A room that has a long reverberation time becomes very noisy as sound ‘bounces’ around and speech becomes unintelligible, making productivity and communication difficult. There are no standards for reverberation time in different

Reverberation Time (Tmf) - Seconds

Internal Space Private Office

0.6 – 0.8

Open Plan Office

0.8 – 1.2

Secondary School Classroom

< 0.8

Primary School Classroom

< 0.6

Atrium

1.5 – 2.0

Restaurant

0.8 – 1.2 Table 1: Recommended reverberation times for internal spaces (Clarke Saunders Associates Acoustics, 2014)

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types of spaces, though some useful recommendations are listed in the Table 1. Reverberation is influenced by the geometry of the room and the materials of the room. The geometry will influence the way in which the sound waves reflect and which frequencies become most amplified. The materials of the room will determine how much of the sound is absorbed, rather than reflected. The frequency of the sound is relevant because different materials will absorb different frequencies. It is therefore important to understand which frequencies are likely to exist in a space and which of these needs to be removed or amplified to achieve appropriate acoustic conditions. The frequency of human speech lies in the mid to high frequency range of about 150 Hz to about 4 kHz. The vowel sounds are produced at frequencies at the lower end of the spectrum while most consonants are produced at the higher frequencies. In order to achieve speech privacy, only the higher frequencies of the speech spectrum need to be removed as speech without consonants becomes unintelligible, though audible. At the same time, lack of clarity means that overheard conversations are less distracting.

Fortunately, higher frequency sound energy can quite easily be absorbed and dissipated by open-cell materials. When sound waves strike a surface, a portion is reflected and a portion is absorbed and transmitted. Sound energy entering an open cell material can be converted to heat and dissipated. The amount of energy that is absorbed depends on the frequency of the sound and the size of the open cells. Different materials have different sound absorption properties at different frequencies. The noise reduction coefficient (NRC) of a material is a single figure (between zero and one) indicating the absorptive properties of a material at different frequency bands. This can be used to assess the effectiveness of a particular product or material (the closer the NRC value is to 1, the better the absorption).

Acoustic challenges in green buildings

To create an indoor acoustic environment that is conducive to occupant health and productivity is very often a challenge in green buildings since many of the other IEQ and energy-efficiency factors can easily contribute to sound transmission rather than attenuation. Post occupancy surveys have indicated that in many cases, the acoustic environment in green buildings is worse than in conventional buildings (Muehleisen, 2011). Some of the factors of green building design that seem to present problems for acoustics are daylighting and external views, natural ventilation, and passive thermal design.

Daylight and external views

Figure 2: Diagrammatic illustration of the reduction of sound energy in a material.

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Maximum penetration of natural daylight and provision of external views is promoted as an aspect of green buildings to improve the indoor environment. In order to achieve this, it is often necessary to have large openplan spaces. The lack of partition walls


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enables the free transmission of sound throughout the space. Large open spaces such as open plan offices tend to have a very long reverberation time as reflected sound waves travel a longer distance. Large glazed surfaces also contribute to the reverberation since they do not absorb much sound energy but rather reflect it back into the space, as well as allowing the transmission of outdoor environmental noise.

Natural ventilation

In a similar way, natural ventilation design can also create acoustic problems. Interior divisions are avoided to allow cross ventilation but at the same time allows sound transmission across a space. Often a central atrium is used in multi-story buildings to create a chimney effect. This not only means that sound can travel across a floor but also between floors. Furthermore, natural ventilation essentially requires openings in the building envelope, allowing the transmission of outdoor noise to the interior, which needs to be addressed correctly.

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Thermal comfort

Passive thermal comfort solutions can also compromise acoustics. The thermal properties of mass elements in a building, such as masonry walls and concrete slabs, can be used for the retention and transfer of heat, thus decreasing the load on mechanical heating and cooling systems. However, this concept requires mass elements to be exposed to the interior. This has resulted in a trend to omit ceilings, exposing the concrete slab above. One problem for acoustic comfort in this type of design is that exposed hard surfaces, like the concrete slab, do not absorb sound well and instead reflect it, resulting in a high reverberation time. Another potential problem to be aware of when ceilings are omitted is that there is less opportunity to attenuate noise generated by exposed services, such as exposed ducting or water pipes.

Acoustic solutions

Good acoustics, however, need not be incompatible with these factors of indoor comfort.

Figure 3: Diagrammatic illustration of noise transfer in passively ventilated atrium building.

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Figure 4: Illustration of sound transmission in open plan office.

Figure 5: Illustration of acoustic solution using ceiling islands in open plan office.

Open plan, exposed mass

Where an open plan design is desired for the benefit of maximising daylight penetration, views and natural ventilation, sound transmission and reverberation can be most easily controlled through the installation of acoustically absorptive materials. This will reduce the amount of sound energy in the space and thus decrease the effect of reverberation. Any soft finishes and furnishings, such as carpets and upholstering, can provide absorption and will also aid in reducing the reverberation time. The effectiveness is dependent on the area and composition of the textiles. Absorptive textiles may be covered with perforated panels to give them structure or to suit the building aesthetics. The perforations can be in any design that provides at least 20% of the absorptive area to be exposed. Acoustic panels composed of suitably absorptive materials of almost any shape, form, dimension and orientation can be installed. These can be merely decoratively or used to demarcate functional zones. A good rule of thumb is that the absorption area should be equivalent to at least 20% of the surface area of the room to be noticeably effective. This leaves a large percentage of the thermal mass exposed.

Acoustic panels need not be directly against the structure and can be creatively positioned in such a way as to minimise interference with daylight and ventilation. An example is the use of floating ceiling islands of acoustic panels, which correctly positioned, could also provide a plane for the reflection of light deeper into the space. Another example would be to clad internal structural elements, such as columns, that do not contribute to the thermal mass in acoustic panels.

Thermal insulation

Thermal comfort achieved through the use of thermal insulation, rather than thermal mass, is extremely compatible with acoustics since most thermal insulation materials also provide good acoustic absorption. For example, a 100mm nonwoven thermal blanket offering a thermal resistance (R-value) of 2 m2K/W could also have a noise reduction coefficient (NRC) of around 0.75. Care should be taken, however, not to make assumptions in this regard as some thermal insulators, such as EPS, do not provide good acoustic absorption. It is important to remember that different materials absorb different sound wave frequencies. It would be futile, for example, to hope to absorb low frequency base

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CHEAPER, QUICKER & STRONGER

Not new to Europe, the USA and Australia, steel frame buildings are increasingly being manufactured and erected in South Africa. Not only are sheds and houses made using steel frame design, but even highrise apartments and hotels are also commonly being erected all over the world. Once cladded with Cromodeck or Nutec Everite sheeting- 9mm, they cannot be distinguished from regular buildings. They offer numerous advantages over traditional brick and wood constructions. These include: • The frames and trusses are extremely lightweight. This makes them safer, easy to handle and easy to transport and erect, requiring less labour. • Modular, computer-assisted designs mean you can custom build them to your specific requirement. • Speed of manufacture and assembly make the steel frame building extremely cost-effective and cuts down delivery time. • Being fireproof is an obvious safety advantage. • Steel frames have inherent design strength and quality is consistently assured, especially when the manufacturer carries nationally recognized certification. • Durable and climate-resistant, the steel frame building will far outlast its normal counterpart and will save on maintenance. • Environment-friendly, with little wastage in construction. The frame is recyclable and not needing wood has obvious advantages in saving trees. • Numerous internal and external cladding options mean the finished product can be aesthetically pleasing as well as full functional. • Plumbing and electrics can be easily accommodated, as can aircons. • Once erected, the design can be easily modified to meet future requirements

Office no: 035 7974925 | Fax no: 035 797 4828 / 086 514 5996 Email: rhconstruction1@gmail.com.


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sound by installing a non-woven insulating blanket in the wall panelling as it would only absorb higher frequencies. However, it may be ideal for creating speech privacy.

Masking and ventilation

Sound masking is the concept of using background noise to â&#x20AC;&#x2DC;coverâ&#x20AC;&#x2122; disturbing or distracting noise. Sometimes white noise is generated electronically to mask conversations and very often the sound of mechanical ventilation provides a masking effect. Running water or simply music playing can also provide sound masking, though care should be taken that the masking sound does not become a disturbing noise. When considering natural ventilation, the open sections in the building envelope allow outdoor noise to penetrate the interior space. This noise can create a masking effect, provided it is not too loud or disturbing. Outdoor noise can additionally establish a sense of connection with the outdoors, which is beneficial in the same way as views to the outside is. Features, such as running water, can be artificially created near open windows to enhance this effect.

Material selection

There are many products and materials available on the market that can provide sound absorption. When selecting acoustic products, the specifier must ensure that the materials used do not compromise any other aspects of green building, having a low carbon footprint, low toxicity, and being resource efficient. Many acoustic products are made from recycled plastic or glass fibres, offering a responsible solution, provided the VOC content is low. These products can be used in conjunction with steel or timber panels to create the desired aesthetic, for example, as a backing to a perforated steel plate. Material must be used efficiently, only using acoustic material where it is necessary and effective. A

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comprehensive understanding of the sound frequencies that need to be addressed will help inform the material choice. Considering that only around 20% of the area of a room needs to be absorptive to make a noticeable difference, anything in great excess of this could be considered wasteful.

Conclusion

Acoustics in buildings, like any other aspect of design, only becomes problematic when the designer neglects to consider it from conception. As an after-thought acoustic installations can compromise the intended aesthetic and functioning of a design but when correctly incorporated, it can provide excellent opportunities for creative and complementary interior solutions. While the basic principle laid out here is to increase the area of absorptive materials in a space, acoustic design can be very much more complex and consultation with an expert may be necessary. A good starting point when considering acoustics in design is to determine the basic requirements of a space by asking whether sound needs to be kept in, kept out, or controlled within the space and whether the need is to create privacy, clarity or quietness. Then, since acoustic solutions are frequency-dependent, one must identify the type of sound to be addressed (such as speech, music, traffic, or machine noise). Once this basic understanding of acoustic requirements has been established, decisions regarding design, material choice and the complexity of the solution can begin to be addressed sensibly. Designers play a significant role in determining how human, environmental and economic resources are invested in buildings. Neglecting to address a single aspect can potentially ruin the investment, wasting resources. A sensually holistic approach to design is thus essential in the design of sustainable buildings. THE GREEN BUILDING HANDBOOK

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References • • • • • • • • • • • • • • •

Berglund, D., Lindvall, T. & Schwella, D., 1999. Guideline for community noise , Geneva: World Health Organization. Bluyssen, P., 2009. The indoor environment handbook: How to make buildings healthy and comfortable. 1 ed. Oxon: Earthscan. Canadian Centre for Occupational Health and Safety, 2007. Canadian Centre for Occupational Health and Safety. [Online] Available at: http://www.ccohs.ca/oshanswers/phys_agents/non_auditory.html [Accessed 28 February 2015]. Clarke Saunders Associates Acoustics, 2014. Clarke Saunders Acoustics. [Online] Available at: http://clarkesaunders.com/reverberation-time/ [Accessed 28 February 2015]. Clements-Croome, D., 2006. Creating the productive workplace. 2 ed. Oxon: Taylor & Francis. Green Building Council South Africa, n.d. Green Building Council SA. [Online] Available at: https://www.gbcsa.org.za/about/what-is-green-building/ [Accessed 21 February 2015]. Muehleisen, R., 2011. Acoustics of green buildings. San Diego, Acoustic Society of America. Paroc, 2015. Paroc. [Online] Available at: http://www.paroc.com/knowhow/sound/sound-absorption [Accessed 28 February 2015]. South African National Standards, 2008. SANS 10103 The measurement and rating of environmental noise with respect to annoyance and to speech communication. Pretoria: Standards South Africa. World Health Organization, 1982. Indoor air pollutants: exposure and health effects, Copenhagen: World Health Organization. World Health Organization, 2011. Burden of disease from environmental noise, Copenhagen: WHO Regional office for Europe.

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PROFILE

MENLYN SHOPPING CENTRE Context and Client directive Developed over some 30 years ago, when Green Building within South Africa was little more than an aspiration within Academic circles, Menlyn has seen various stages of expansion, alteration and redevelopment culminating with the 2000 redevelopment, which received an ICSC International Design Award. In 2008 the owners reaffirmed their development strategy to ensure the Centre’s continued position as their premiere Super Regional Centre. This resulted in the concept design for a redevelopment expanding onto the adjacent disused western brownfield site and reconstruction of the existing Checkers Hyper box over two levels, resulting in a total GBA of 245 000m² in 2016. The owners stipulated that the redevelopment should encompass their ongoing commitment to good environmental stewardship. Thus the design and completed development are being submitted to the Green Building Council for a 4 Star design and as built accreditation. Rising to meet this challenge was simply not possible solely through inclusion of new materials and technologies. Additionally strategies have been followed with the aim of influencing the energy consumption and procurement behaviour of the tenants – the party with the greatest environmental footprint – considerably greater than base building.

Strategies

Design 101 Menlyn by definition contains a number of inherent constraints, i.e. extent and orientation of existing envelope, construction and infrastructure etc. Whilst the budget included an allowance for “Green” components, not all solutions can be achieved through financial support for new

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materials and technologies. This is specifically pertinent to a building of this scale – a minor increase in a component or finish cost can become a considerable addition to the budget. Principals of good design and detailing have been used to limit such financial burdens. An example of this is orientation and lighting. Menlyn’s considerable energy consumption is exacerbated by the “deep box” nature of the floor plate and consequential need for artificial illumination. During the concept design phase the desire for a more open, spacious and naturally lit environment was addressed through provision of large mono-pitch roofs with clearstory side lights over double level malls. This approach has greatly reduced the need for artificial lighting. Moreover this direction of natural light into tenant spaces lowers their need for artificial lighting which facilitates the utilisation of green leases. Whilst this solution allows natural light into the malls, it was recognised as a challenge for HVAC environmental control. Consequentially the design utilises orientation, large overhangs, performance glazing and appropriate roof construction to minimise the heat load.

Methodology & Technology Aspects of construction methodology and technology have been embraced as one of


PROFILE the ‘tools’ used to achieve the desired Green Star rating. Constructionally the scale of the project has dictated a need to reduce wastage and reclaim materials from demolitions & earthworks activities for reuse within the project or off site. This was managed through a Waste and Recycling Management Plan monitored by the Principal Contractor and the Green Building Consultant. An aspect that has previously had little emphasis, if any, is the need for additional administration resources to monitor and implement the specification, sourcing, procurement and installation of “Green” products and materials. This equally applies to the Contractors and Consultants, i.e. increasingly accurate product choice and specification requirements to ensure conformity. These all add to the time constraints on such a Fast Track project. Technologically some of the “Green” aspects used in the project include: • Rainwater reclamation • Grey Water utilisation • Lighting Management • LED lighting • Economy Cycle AHUs • Variable speed pumps & leak detection • CO² and CO monitoring BIM and Teamwork Methodology With the project’s sheer scale and extremely fast-track approach it was imperative that the traditional “silo” approach be consigned to the dustbin. At commencement it was determined that great assistance would be

achieved through implementation of Building Information Modelling processes. These processes and tools have allowed for a more inclusive approach to the realisation of the project design and detailing – from design concept presentation to energy consumption and lighting. Whilst BIM has enormous potential for free, flexible, prompt, and accurate information flow between parties, they required adjustment to suit the exigencies of this Fast Track project and the South African context. Inclusivity If large projects are to be successful, new tools can only take you so far. The most important lesson throughout the project has been that greater complexity needs greater professionalism and teamwork. As alluded to earlier the greatest user of materials and energy in completing a development of this nature are Tenant installations. Thus, ideally, Green Star evaluation criteria should eventually also measure and include the specific behaviour of the tenants themselves. Utilisation of green leases by the developer has greatly helped in moving towards this.

Conclusion Whilst this article describes and alludes to some of the strategies, designs and components followed it is recognised that of its very nature it can only be a taster as to some of the more pertinent aspects. It is hoped however that it has given an indication of the intricacies, extent and scope of this major development.

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ACCELERATING THE GREEN AGENDA THROUGH INNOVATIVE BUILDING TECHNOLOGIES

Llewellyn van Wyk


This chapter flows out of a study (CSIR 2013b) prepared for the Presidential Infrastructure Coordinating Commission (PICC) in May 2013 which prepared a value proposition for the use of Innovative Building Technology (IBT) for the construction of clinics, schools, and student residences.


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Aim and Objective

The aim of the study was to encourage innovation in the building industry as a means of accelerating green building. Green building rating systems include, as part of their objectives, demonstrating leadership to the building industry with regard to improving the environmental performance of buildings. The Green Star rating system is advocated on the following premise (GBCSA 2015): • Establish a common language and standard of measurement for green buildings; • Promote integrated, whole-building design; • Raise awareness of green building benefits; • Recognise and reward environmental leadership; and • Reduce the environmental impact of development. While rating systems have achieved various degrees of success with regard to the above, international industry reports (see later) hold the view that systemic challenges within the industry continue to impede an industry-wide transition to true sustainability. Similarly, the lack of innovation in the building industry is seen as one of the systemic challenges impeding transformation – a factor recognised by rating tools through the encouragement of green innovation. The main objective of the study was to analyse, compare and validate the efficacy of IBT (time, cost and performance) in accelerating green and sustainable building in South Africa. The secondary objectives were to: • Quantify the benefits accruing to a project from IBT (time, cost, performance). • Quantify the benefits accruing to the country from IBT (local beneficiation,

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• • • •

• •

economic growth, job creation, skills development). Support the development of a viable IBT industry in South Africa. Reduce the quantity and mass of materials used in the building process. Develop and utilise construction materials with low embodied water. Develop and utilise construction materials with a low maintenance requirement. Strengthen the local content of IBT. Develop and utilise construction materials with low toxicity.

Rationale

The construction industry in South Africa, particularly the building sub-sector, has a critical role to play in delivering social infrastructure facilities. However, the delivery process associated with conventional building technologies, i.e., brick and mortar, is slow due, in large part, to the technology requirements (diverse and plentiful building systems, products and components assembled on site and the curing periods associated with ‘wet’ works). Some IBT’s on the other hand, adopt a more industrial approach to building and construction, i.e., more of the building systems, products and components are manufactured in a factory, and assembled on site. This method improves performance because quality control can be properly exercised under factory conditions, and the amount of time required on the construction site is reduced.

Construction reform

There has been numerous construction industry initiatives globally aimed at improving construction performance. From a review of these global initiatives as well as the South African Construction Industry Status Report, 10 systemic issues affecting


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construction industry performance in South Africa are identified (CSIR 2006). These are: • Poorly integrated delivery system. • Low performance expectations. • Poor knowledge base. • Inadequate construction inspections. • Inadequate construction warranties and services certification. • Complicated procurement environment. • Social, environmental and economic challenges. • Inadequate quality-based regulatory environment. • Poor business acumen, management and innovation. • Inadequate research and development.

Research method

For the investigative research a mixedmethod approach is adopted where both quantitative and qualitative analysis is used to arrive at a conclusion. The primary research question set is: how, and in what way, can the use of IBT assist building infrastructure delivery in a manner that delivers improved performance and sustainable human settlements? Five secondary questions are posed for discussion, namely: • What is innovative building technology • Why is innovative building technology used • Where is innovative building technology used • How do innovative building technologies perform • What is the value proposition promised by innovative building technologies Research plan The research plan used for the study is shown below. Data collection The following sources were used:

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• CSIR Parliamentary Grant Funded Research – the advancement of construction has been a focus of the CSIR Building Science and Technology competence area under the banner of the Advanced Construction Technology Platform (ACTP) for over a decade and numerous research reports prepared on the subject. • Literature Review – a desktop study was undertaken to obtain data pertaining to the main objective of this study. • Interviews – interviews were held with construction industry specialists both in South Africa and abroad. • Conference Papers – the CIB World Congress 2013 was attended in Brisbane Australia to obtain first-hand knowledge of the status of alternative building methods and technologies as well as to hold interviews with leading international academics and researchers in construction. This academic conference is held every three years and concludes a three year research cycle. • Case studies – use was made of three case studies to gain actual data based on South African projects where IBT were utilised. • Data collation – data collected from the research sources was collated using the primary and secondary research questions. • Synthesis – the data was synthesised to answer the sub-questions. • Conclusion – the synthesised data was used to derive a conclusion. Limitations The following limitations apply to this study: • The availability of data on the use of IBT in South Africa is limited: Statistics South Africa does not capture construction data based on technology types.

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• Only a few IBT trade associations exist, thereby impeding access to data about technology uptake in the building sector. • Time restrictions applied to the research study, thus limiting the depth to which the study could delve. More time would be required for a thorough analysis to be done. • Much of the data included in this report was provided by contractors and although their bona fides is not contested, the data has not been validated by the CSIR. Delimitations: The following delimitations apply to this study. • The study was located within the context of IBT, an international initiative to shift construction away from on-site bespoke construction to off-site manufactured construction. • A Life Cycle Analysis had not been done to determine the environmental performance of IBT. • No economic impact assessment had been undertaken.

What are Innovative Building Technologies?

Innovative Building Technologies (IBT) in the context of the study was the use of materials other than brick and mortar, and the use of construction methods other than on site mixing and erection. Within the building regulatory environment IBT refers to the use of materials and technologies not covered by the SANS 10400 building standards in the National Building Regulations and Building Standards Act 103 of 1977 (NBR Act), and where building permission is granted for such systems, materials and technologies based on either a rational design or an Agrément Certificate.

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IBT can generally de described by its materials, i.e., either light (steel frames) or heavy (concrete panels), and methods, i.e., either on site (mixing and erection of raw materials on the construction site) or offsite (factory-based fabrication). Globally IBT’s form part of a larger initiative aimed at industrialising construction, i.e., the building process is more closely aligned with a manufacturing process where more of the components are manufactured and assembled on the factory floor and delivered to the construction site in modules of various sizes. This form of construction is known variously as Offsite Manufacturing (OSM), Modular Construction, Modern Methods of Construction, and Prefabrication. In the context of this chapter IBT is defined as using alternative building materials, usually lightweight materials such as light steel frame sections, and offsite building technologies, where more of the components are manufactured on a factory floor.

Why are Innovative Building Technologies used?

The use of IBT is predicated on the desire to reduce the time (reductions of up to 35%) and cost (savings of up 41%) of construction, to improve the quality of construction, and to improve the performance and the sustainability of construction products (CSIR 2013). The need to create a stimulating and rewarding working environment in order to attract young people to the sector is also a primary driver of IBT. The case study (CSIR 2013a) found sufficient evidence to support IBT claims of cost benefits (reductions of up to 41%) and time benefits (up to 35%) as well as health, quality and sustainability improvements through international and local case study and questionnaires.


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Buildings, both the construction and operation thereof, are a significant consumer of scarce resources. It is typically referred to as the ‘40% industry’ – 40% of energy consumption, water consumption and raw material consumption can be ascribed to the global construction industry. The increasing demand for a stepchange in the performance of buildings is something that traditional construction method struggles to deliver. To ensure high levels of performance requires a high degree of accuracy in the construction process. This is expensive to achieve through traditional construction methods and the inevitable reworking and additional use of materials and investment in additional levels of supervision. This approach is costing money and eventually all such additional costs will accrue to the client. Adopting an approach to construction based on the assembly of components manufactured in factories to a high level of accuracy offers a realistic and much more certain approach to achieve the required levels of performance. The uncertainty and inconsistency of traditional methods does not offer a similar opportunity (Buildoffsite 2012). Traditional construction methods give rise to significant waste of material whether as a result of the common practice of overordering, ‘shrinkage’, reworking to remedy defects of poor quality, or damage on site. No matter what the cause the client ends up paying for every scrap of material that is wasted and paying again for landfill. Aside from the financial cost this practice has a significant impact on the environment. There is no sign that the traditional construction industry has been able to effect any significant improvement in practice and frankly as the cost is simply passed on to the client and end user there is no incentive for change. The manufacturing and assembly of offsite construction solutions give rise to

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very little waste to landfill. Manufacturing waste is modest, readily measurable and in almost all cases collected for reuse and recycling (Buildoffsite 2012). To achieve high performance green buildings will require the adoption of advanced and innovative technologies which conventional building techniques have struggled to achieve over the past 30 years. To achieve sustainable building and construction activities requires the development of the third generation of construction materials and methods, essentially those emerging as part of IBT. It would be mistake to see the shift towards IBT solely as a response to more rapid social infrastructure delivery: on the contrary, a shift toward IBT can be the catalyst for construction sector reform. Numerous initiatives have been undertaken by various countries to enhance the capability of their construction industry particularly since the end of World War II. Stakeholders of the construction industry have responded to global challenges and domestic pressures exerted on the industry through research resulting in a series of major studies undertaken over the past 50 years. Studies within the international arena include several by international agencies such as the United Nations, the World Bank, the International Bank for Reconstruction and Development, and the International Labour Office. Governments, clients and contractor organisations have also invested heavily in initiatives aimed at reforming the construction sector, with a specific emphasis on industry performance improvements and on increasing the sector’s ability to innovate. The U.K. industry in particular undertook a spate of investigations such as the Simon (1944), Banwell (1964), Wells (1986), Latham (1994), Levene (1995), and Egan (1999) reports. These stimulated widespread

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IT STARTS HERE!

SUSTAINABILITY

WEEK 23

African Capital Cities Sustainability Forum Sustainability in Mining

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Green Building Conference Day 1 Sustainable Energy Seminar Day 1 Food Security Seminar Transport and Mobility Seminar Green Manufacturing and Supply Chain Seminar

25

Sustainable Energy Seminar Day 2 Sustainable Infrastructure Seminar Vision Zero Waste Seminar Water Resource Seminar Responsible Tourism Dialogue Green Business Seminar

26

Youth and the Green Economy Seminar

27-28

Green Home Fair

CSIR INTERNATIONAL CONVENTION CENTRE

23-28 JUNE 2015

www.sustainabilityweek.co.za

021 447 4733

sales@alive2green.com


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international interest and spurned a spate of similar initiatives, including countries such as Ireland, Sweden, Finland, Australia, Singapore and more recently, Netherlands. In the main the objective has been to elevate the construction industry into a vibrant, reputable and professional sector. Some have opted for best practice-type improvements to enhance delivery quality while others are actively pursuing new technologies. In reviewing the industry visions and strategies of these studies, the following issues appeared most consistently (CSIR 2006): • Technology as an agent of change – many of the visions recognise the need for the industry to become more innovative and to a greater or lesser extent look to technology as the vehicle. Huge variations exist in terms of which technologies should be pursued, although the drive toward the greater use of off-site assembly processes appears consistently, especially in the Asian region. • Strategies and structures for achieving change – this includes the respective roles of official and industry bodies, strategy preparation and communication, and how individual stakeholders can participate in the change process. • Procurement as a driver of behaviour – this examines the degree to which procuring bodies can shape industry performance through their ongoing purchasing power, including new contractual and financing systems, the balance between imposed and negotiated requirements, and the entire supply chain delivery process. • Monitoring and evaluating change – every strategy has a monitoring system attached to determine the extent to which the objectives are being met,

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and usually includes benchmarking and indicators in its application. • Regulatory environment – the introduction of statutory controls is a common approach to driving behaviour, although some markets are less amenable to government intervention than others. • Human capital – without fail, all visions recognise the dire need to greatly advance the depth of human capital within the construction industry, and advocate a number of strategies aimed at attracting skills, encouraging change, training for change, and creating a safe and healthy workplace conducive to innovation and improved productivity.

Where are Innovative Building Technologies used?

The uptake of IBT as defined for this study is generally higher in countries that have a tradition of light weight construction whereas the uptake is low in countries that have a tradition of brick and mortar construction. However the market penetration of IBT is increasing in the latter markets in response to the pressures emanating from raw materials scarcity, the demand for higher performing buildings, the need to reduce associated construction risks, and the need to reduce construction costs. In the BRICS countries interest in IBT is growing in response to developmental challenges with both China and Brazil showing an increased appetite to move in this direction. Certainly the use of prefabrication is fairly common in the BRICS countries especially with regard to precast concrete panels. There is evidence that light steel frame construction and structurally insulated panels are used in Brazil, Russia, India and China. However, the interest is

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now extending to innovative and advanced construction materials in the search for high performance, green buildings. In this regard Brazil is a member of the World Federation of Technical Assessment Organisations (WFTAO), an organisation which supports the technical assessment of non-standard systems and of which Agrément South Africa is a member as well.

How do Innovative Building Technologies perform?

Agrément South Africa certifies nonstandard building products and systems as fit-for-purpose by assessing the product and/or system against performance criteria. These criteria ensure that the system meets the performance requirements of the NBR Act. For purposes of the study (CSIR 2013b) each certified system was scrutinised to determine whether the system was certified for the targeted use, i.e., clinics, schools, and student residences. In addition, only those systems with maximal local content were selected. The selected systems were then scored against key performance indicators derived from the Agrément Certificates and compared to a Standard Brick House (SBH), the benchmark used by Agrément as it meets the requirements of the NBR Act. The result showed that the SBH scores an aggregate of 3.6. This places the SBH 32nd out of a total of 40 building systems according to the performance criteria as set out. From this data it may be said that most of the systems outperform the standard brick house. To assist in the selection process the CSIR has developed an assessment tool – the IBT Rating Tool – to rate systems on optimal performance with regards to building performance, logistics, and climatic conditions.

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What is the value proposition?

From the data it is evident that IBT demonstrate significant value-add to construction products. Sufficient evidence exists to confirm that IBT reduce construction cost by about 41% on average in South Africa depending on type and location; reduces construction time (by up to 50% in South Africa) depending on type and location; out-performs the standard brick house (SBH ranks 32nd out of the 40 systems); reduces the construction costs of schools by up to R2 749/sq.m. (from R7 581 to R4 832); reduces the per student bed cost in student residences by up to R44,146 offering a potential R8,8bn saving on the 200,000 bed backlog; and can act as an agent of construction industry reform by supporting the industrialisation strategy, local raw material beneficiation; the creation of decent jobs; and the green economy. As stated earlier, it would be a missed opportunity to simply procure IBT to expedite construction delivery – the significance of IBT is located in the technology step-change and the ability to deliver construction products on time, to quality, to budget, with enhanced building performance. Using the ten systemic issues undermining construction industry performance identified in the Foresight Report (CSIR 2006), IBT’s are able to overcome each of the systemic issues identified in the Status Report, namely; • Simplifying the delivery system • Establishing performance expectations • Strengthening the knowledge base • Adding to construction inspections • Enhancing construction warranties and services certification • Establishing defined procurement protocols

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• Enhancing economic, social and environmental performance • Strengthening business acumen, management and innovation • Supporting research and development

Conclusion

Buildings and infrastructure contribute in large measure to the quality of people’s living-, working- and leisure environment. But they also provide the infrastructure for mobility, industrial and commercial activities. It is clear in this way that a lack of innovation in the construction sector directly influences the costs and competitiveness of other industrial or economic activities within South Africa. For those reasons, innovation in the construction sector should be a major concern of South African institutions. More than ever any focus on the construction industry must bring about a new total construction capability founded on customer orientation (addressing of unique processes), environmental design-based consciousness (ecological judgement), and a technology-driven (knowledge and expertise) delivery chain, including the built environment professions, material manufacturers and contractors.

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This will result in a re-conceptualisation of construction delivery best practice away from determining what processes are required from a construction perspective to what processes are required for the optimal formation of immovable assets. Inherent in this refocus is the building of construction competence and product knowledge on the basis of post-completion evaluation, assessment and re-application to achieve immovable asset fitness-for-purpose. The study showed that IBT’s offers an opportunity for a technology transfer paradigm shift that will transform traditional construction methods into a manufactured production process that will benefit society through improved property performance, which will directly impact national concerns about the environment, the state of social infrastructure and the improvement of the quality of life of communities. The study shows that IBT’s outperform conventional building technologies against a basket of indicators, and without a loss of quality. In addition, the study shows that both cost and time is reduced, and that working conditions are greatly improved, creating decent jobs and making the construction sector more inviting for young entrants.

References • • • • •

Buildoffsite 2012. Buildoffsite review 2012: the business case for offsite. United Kingdom: Buildoffsite. GBCSA 2015. What is Green Star SA? [Online] Available from https://www.gbcsa.org.za/greenstar-rating-tools/office-rating-tool/ [Downloaded: 2015-03-03]. CSIR 2006. Foresight – South African Construction 2014. Pretoria: Council for Scientific and Industrial Research. CSIR 2013a. Comparative analysis between alternative building technologies and conventional brick and mortar. Pretoria: Council for Scientific and Industrial Research. CSIR 2013b. Innovative building technology: value proposition. Pretoria: Council for Scientific and Industrial Research.

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COROBRIK’S SUSTAINABILITY PROFILE Clay brick intrinsically sustainable and in harmony with natural environments A programme of continuous improvement continues to be followed at Corobrik to lower the environmental impacts of its operations this to support and compound the value that the generic intrinsic properties of clay brick contribute to sustainable built-in environments.

climates and lower the operational energy usage of buildings.

Clay Brick – Intrinsicly Sustainable Fired clay brick is one of only a few man-made walling materials that is proven reusable and/or recyclable. Robustness and extreme durability mitigates future carbon debt associated with refurbishment and replacement of less durable building materials and it is longevity that provides the time opportunity for embodied energy to dissipate. The mineral properties and inert non-toxic qualities of fired clay brick well recognised for meeting all necessary requirements for healthy living, further defines clay bricks enduring environmentally sensitive proposition. It is such qualities, coupled with the colourfast maintenance-free attributes of face brick that help mitigate future carbon debt associated with painting, that adds further substance to clay bricks sustainability proposition. And then one cannot overlook the natural thermal performance properties of clay brick, proven through extensive empirical and modelling research to support greater thermal comfort conditions within South African

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Clay brick walling supports thermal comfort conditions In the above graph from the study by WSP Green by Design of a 40 m² low cost house, the three double skin Corobrik clay brick walled alternates [with the requisite thermal capacity and low R-values] accounted for the generally superior thermal performance, greater thermal comfort and lower energy usage for heating and cooling than the insulated lightweight walled alternates [with higher resistance but low thermal capacity]. The sum total of research findings is that, for climates akin to South Africa, clay brick walls for houses can be specified to assure greatest thermal comfort and optimal energy efficiency with best payback for the level of insulation applied, outperforming


PROFILE

THERMAL MODELLING OF VERDANT AND SIROCCO HOUSE PLANS AVERAGE HVAC GREEN HOUSE GAS (kg CO2-e) EMISSIONS OVER 50 YEARS Extracted from Energetics Full Life Cycle Assessment Location

Four Orientations

Uninsulated Double Brick

Insulated Double Brick (R1.3)

Insulated Timber Frame

Insulated Timber more/ (less) GHG than Double Brick

Insulated Timber more/ (less) GHG than Double Brick Insulated R1.3

Newcastle Climatic Zone

N,S,E&W

108273

102471

137053

11.67%

18.00%

Melbourne Climatic Zone

N,S,E&W

146100

127281

145139

11.67%

14.03%

Melbourne Climatic Zone

N,S,E&W

129847

130020

145108

11.75%

11.60%

Average GHG

N,S,E&W

128073

137053

137053

7.01%

14.28%

comparable insulated lightweight walling. The heating and cooling energy savings of clay brick construction are significant, with the full Lifecycle Assessment by Energetics in Australia – see table above - going so far as to show that the savings provided by cavity brick walling offset clay brick wallings higher embodied energy to provide a lower total energy usage [embodied plus operational] compared to timber frame insulated weatherboard in most situations, with insulated cavity brick walling providing lowest total energy usage and lowest GHG emissions in all situations. These performance attributes of clay brick, along with South Africa’s strong masonry tradition and society’s broad preference to live in brick houses, combine to underpin clay bricks pre-eminent status for sustainable house construction and infrastructure buildings – schools, clinics etc.

Making Corobrik’s Business Greener Corobrik’s approach to reducing environmental impacts in the business has concentrated on quarrying clay materials within a sustainable development framework, achieving greater resource efficiencies and lowering the consumption of non-renewable resources. Progress made has elevated the environmental integrity of Corobrik’s products beyond the sustainable qualities generic in fired clay. The interventions include: i. Dematerialisation Through investment in advanced extrusion technologies dematerialization with enhanced product quality, performance attributes has been achieved. Resultant energy usage reductions through dematerialization include: • Reductions in drying and firing energy usage in the order of 20 per cent when THE GREEN BUILDING HANDBOOK

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PROFILE compared to a ‘standard’ three core-hole brick with 20 percent perforations. • Reduced diesel usage per thousand bricks delivered. • An eight per cent reduced mortar usage on site reducing the carbon footprint associated with the cement component of mortar.

Corobrik’s Kliprug quarry – now a residential estate with vineyards

Efficiency through advanced technologies

ii. Lowering the carbon footprint through the use of cleaner burning fuels For each giga joule of energy, natural gas releases just 48kgs of CO2 compared to 97kgs of CO2 emitted from coal. In 1996 Corobrik committed to a process of converting to natural gas for the firing of its kilns. Today, Corobrik has six major factories using natural gas as a primary fuel for the firing of its kilns, bringing to the South African market clay bricks with embodied energy values in line with best international practice for the clay types and the manufacturing technologies employed. Further conversions are being pursued but remain dependent on the availability of natural gas at the factory gate. Corobrik has the distinction of being the first company in South Africa to be issued Certificates of Emissions Reductions by the United Nations Clean Development Mechanism for its fuel switch programme – Lawley Factory conversion. Corobrik presently has two CDM projects registered with UNFCCC. iii. Lowering electrical energy consumption Teams are in place at all operations with a mandate to reduce electrical energy usage. Through power correction interventions and modifying shift activities thereby circumventing high electrical energy usage at peak periods, electrical energy usage has dropped significantly throughout with further savings being explored.

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iv. Use of recycled materials in the production process Most ‘green’ brick waste is recycled back into the clay production processes. Burnt brick


PROFILE waste is either crushed as aggregate for use in road building applications, or the manufacture of concrete products. Surplus aggregate is returned to the quarry from where it came. In addition suitable waste materials from other waste streams are regularly evaluated for their suitability as a recycled component in our the brick manufacturing processes. At this stage we have not been able to source suitable waste materials that meet the environmental requirements of a ISO 14001 certified factory.

three typical technologies Corobrik employs, ranges between 23.2 and 33.8 Kg CO2/ m² single skin of brickwork. This equates to between 215 and 250 tCO2 per tonne of bricks against the international average of approximately 300 tCO2 per tonne of bricks. Ideas and interventions with the potential to effect incremental reductions in emissions are continually being assessed and implemented where appropriate.

v. ISO 9001:2008 Quality Management Certification at factories Corobrik has 10 factories with ISO 9001 Certification with others busy with the accreditation process.

Building on progress made, sustainability at Corobrik is set to continue forward during 2015 through the ongoing broadening of understanding, knowledge and commitment in the business for addressing the sustainability imperative. In addition to the above, Corobrik will continue to invest in research to understand how brick may be better specified in buildings to lower environmental impacts and to help develop specifications for masonry walling able to facilitate optimal thermal performance outcomes – greatest energy efficiency and payback for the built cost. This is presently being advanced through our membership of the Clay Brick Association of South Africa, where Corobrik is involved in the commissioning of the ground breaking full Life Cycle Assessment of clay brick in South Africa being undertaken by the University of Pretoria. This assessment is to consider the contribution of clay brick to sustainability in the three dimensions environmental, economic and social.

vi. ISO 14001:2004 Environmental Management Systems Certification at factories Corobrik has five factories with ISO 14001 Certification with others busy with the accreditation process. It is the two processes of achieving Quality and Environmental certification, coupled with Corobrik’s commitment to employing international best practices at its operations that has helped drive down Corobrik’s carbon footprint and enhance eco systems around operations.

The Carbon Footprint of Corobrik bricks As calculated by CSIR Built Environment, the embodied energy of clay bricks from

Continuous improvement

Corobrik Factory

Avoca 1 Transverse Arch Kiln

Lawley 2 Transverse Arch Kiln

Midrand Tunnel Kiln

Product Type in Imperial Format

Clay Plaster Bricks

Clay Face Bricks

Clay Face Bricks

Kg CO₂/m² Single Skin Brickwork

29.3

33.8

23.2

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FEASIBILITY OF GENERATING ELECTRICITY FOR CLINICS USING WIND TURBINES Steve Szewczuk


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M

any primary healthcare facilities currently suffer from poor infrastructure quality and problems with the procurement of infrastructure. In 2013 the CSIR embarked on a research project to develop a design terms of reference and blueprint designs for modular conventional clinics and for the rapid deployment of clinics. In the final phase of the project it was intended to construct and commission a new design pilot clinic(s). The outcome of the project was to be high quality clinic facilities and standardised procurement practices. Studies undertaken by the Infrastructure Unit of the National Department of Health had identified a number of challenges to the delivery of healthcare infrastructure. Many of these challenges are addressed through the Infrastructure Unit Systems Support (IUSS) project with the National Department of Health. This chapter describes the investigation undertaken to evaluate the feasibility of using wind turbines to provide electricity to the clinics.

Problem statement

Historical funding models have recognised the entrenched inequity and furthermore undermined affordability of healthcare services in South Africa. The National Department of Health is introducing the National Health Insurance scheme to integrate healthcare services. This will be heralded by a renewed focus on primary health care provision and will be accompanied by an initiative to reengineer primary health care services. Major implications, such as shifting to increased community outreach services (as opposed to facility-based services); emerging requirements for information networks (for NHI management) are foreseen. As infrastructure is integral to the delivery of health care services, these organisational

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transformations provide an extraordinary opportunity for Science, Engineering and Technology (SET) input into the strategic planning, design, specification, equipping, and decommissioning of primary healthcare facilities. Many primary healthcare facilities currently suffer from poor infrastructure quality and problems with the procurement of infrastructure. Buildings and their operations depend on the continued supply of services such as water, sanitation and electricity. However, service delivery failures do occur whether due to operational factors such as regular maintenance or system failure, or due to service protests. Critical services such as primary health care rely on a stable service provision especially with regard to sanitation, electricity and the proper storage of drugs. Alternative infrastructure service technologies are technologies that can be implemented to provide alternative methods for securing a stable infrastructure service. One of the strategies that can be employed to ensure an uninterrupted service is to reduce the buildingâ&#x20AC;&#x2122;s exposure to municipal services. This will assist the building to adapt to major perturbations and events without a disruption in service delivery. Reducing the buildingâ&#x20AC;&#x2122;s dependence on municipal services will also reduce the operational costs of the building.

Situational analysis

Primary healthcare services are kingpin to the healthcare services in South Africa. It is recognised that prioritisation of care at this level of service is uniquely suitable to promote good health, prevent ill-health and avert demand for services at higher (more expensive) levels of care. In order for South Africans to benefit in this way, primary healthcare services need to be inclusive, accessible, affordable and high quality. Primary healthcare service delivery


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is severely hampered by lack of, and poor quality infrastructure. In many cases the physical infrastructure at clinics is old, inadequate and in some cases not suitable for use. The provision of services (water, sanitation and electricity) is in many cases not adequate, especially in rural areas. In addition to this, no standardised clinic design and lifecycle management tools currently exist. This results in poor infrastructural investment decision making, problematic procurement processes and practices and poor maintenance of existing facilities. Re-engineering of primary healthcare as the main mechanism of healthcare service delivery requires urgent intervention at the infrastructure level. Studies undertaken by the Infrastructure Unit of the National Department of Health had identified a number of challenges to the delivery of healthcare infrastructure. These included: • South African health infrastructure norms and standards for all stages of the building life-cycle are out dated. Lack of a sustainable set of universally adopted, current national norms, standards, guidelines and benchmarks is hampering rapid planning, design, construction and operation of these facilities. Norms and standards have been identified as a priority programme area. • Until the 2007/08 financial year, the National Department of Health control over provincial capital expenditure was weak. As a result, many incidents of reallocation of earmarked HRP Hospital Revitalization Programme (HRP) Grant funding were observed and reported. Conventional procurement strategies and methods persist, resulting in long delays in awarding professional services and contracts. • There has not been a strong and scientifically based project and program

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management system in place to monitor and then improve the infrastructure delivery system at either national or provincial level. There has been a steady increase in budget allocation to health infrastructure through various funding mechanisms - Hospital Revitalization Programme (HRP), Parliamentary Infrastructure Grant (PIG) and Equitable Share (ES) - between 2004 and 2011. Even although there has been a concurrent increase in expenditure, of concern, however is the consistent under-expenditure. To overcome this shortcoming a Project Management Information System (PMIS) is required. • Delivery capacity of implementing agents (works departments, and others) as well as the provincial department of health did not match budget increase. The roles of National Department of Health on monitoring and oversight were minimal and confined to ‘watching’. In the 2007/08 financial year the peer review mechanism was introduced. Projects monitoring and oversight support mechanisms should be strengthened. • As budget requests are met primarily through Treasury loans, a more ‘realistic’ match between allocation and delivery capacity is required to avoid incurring unnecessary finance costs. Given poor spending patterns, a more considered approach and conservative budget allocation may be advisable and should be investigated. To overcome this shortcoming an infrastructure cost model is required. In the context of this background the Infrastructure Unit approached the CSIR and DBSA to assist in the development and support of some systems to assist in the optimisation of public health care infrastructure planning, design procurement

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PERFORMANCE CEILINGS Mo re scope for i nnovati on

Knauf AMF Ceiling system location Headquarter Grafenau, Germany

With the strong brands AMF THERMATEX速, AMF VENTATEC速 and HERADESIGN速, the ceiling specialists Knauf AMF offers a fully developed product range and exceptional sales and advisory services to architects, specialist contractors, developers and distributors throughout the world. With us, you are always a ceiling solution ahead! Knauf AMF Southern Africa P.O. Box 85, Ruimsig 1732 - Roodepoort, Gauteng Tel.: +27 11 768 4373, Fax: +27 11 768 4373 E-mail: motlhathudi.thabo@knaufamf.co.za, http://www.amfceilings.com


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and operation. This project started in the 2010/2011 financial year and is known as the Infrastructure Unit systems Support (IUSS) project. A work package was defined for each of the five areas mentioned above. The project also has extensive consultation processes – a series of 46 work packages, each with its own committee, is used to get to the development of norms and standards. There is no accurate data on the number of clinics in South Africa, but the most accurate indication available is a number of more than 3500. This flagship project will build on the norms and standards that are developed as part of the IUSS project to ensure primary healthcare facilities of the appropriate quality are delivered.

Description of the project

Infrastructure is an integral part of primary healthcare delivery and improvement of the quality of health infrastructure has been identified by the National Department of Health as a high priority for improving healthcare service delivery. This project aimed to optimise the quality, accessibility, lifecycle management and cost of primary healthcare physical infrastructure by building on the work that has been done in the IUSS project on norms and standards for clinic design. A standardised clinic infrastructure solution(s) was to be developed. This would allow implementation of a standard procurement package thereby enabling improved financial governance.

Goal of the project

The project has a hierarchy of goals and objectives. The ultimate goal of the project was to erect a new basic clinic building and a clinic that could be rapidly deployed with the support of the National Department of Health. The new buildings would make use of alternative construction methods and the procurement of the buildings would

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be standardised. These buildings would be based on the blueprints developed as part of this project.

Alternative infrastructure services technologies: wind turbines

It is intended that all the power required to operate a clinic should be generated on site allowing the building to function off-grid. A review was done of wind turbine machines of less than 100kW in size. (Szewczuk et al, 2010) Topics covered were: • Markets and applications • Market drivers and barriers • Review of common applications of SWT’s Small-scale remote and off-grid power (residential, village or remote) are used for supplying energy to rural, off-grid applications in the developed and developing world. This market encompasses either individual homes or small community applications and is usually integrated with other components, such as storage and power converters and PV systems. Residential and on-grid power is small wind turbines used in residential settings that are installed using net metering to supply energy directly to the home. Excess energy is sold back to the supplying utility. Farm, business and small industrial wind applications are used for supplying farms, businesses and small industrial applications with electric power. The loads represented by this sector are larger than most residential applications, and payback must be equivalent to similar expenditures (4 to 7 years). In many cases, businesses are not eligible for net metering applications thus the commercial loads must use most of the power from the turbine. ‘Small-scale’ community wind is a system using wind turbines to power grid-connected loads such as schools,

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public lighting, government buildings and municipal services. Turbines can range in size from very small, several-kW turbines to small clusters of utility-scale multi-megawatt turbines. The key defining factor is that these systems are owned by or for the community. Wind/diesel power systems are used for providing power to rural communities currently supplied through diesel technology in an effort to reduce the amount of diesel fuel consumed. The rising cost of diesel fuel and increased environmental concerns regarding diesel fuel, transportation and storage have made project economics more sensible.

Available wind in South Africa

South Africa’s wind resources are influenced by the large scale weather patterns that have distinct characteristics between summer and winter.

Summer Winds

In summer, the ‘Westerlies’ are situated well to the south of the continent (Figure 1). The south-eastern Trade Winds (A) influence

Figure 1: Summer winds over South Africa Winter Winds

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the north-eastern part of the region. These winds can be strong, curving sometimes from the Limpopo Province (N) into the Free State Province (F), or moving over far northern areas, such as Zimbabwe and Zambia (Z). In the west, the South East Trade Wind (B) caused by ridging of South Atlantic High, are often strong and persistent. The strong ‘Westerlies’ are only able to influence the western, southern and south-eastern coastal areas and adjacent interior. In winter all the circulation features (Figure 2) are situated more to the north than in summer. Strong winds and gusts during winter are usually caused by strong cold fronts, moving mostly over the southern half of South Africa, and also by the ridging of the high pressure systems behind the fronts. The ‘Westerlies’ influence the weather of the southern and central parts of the subcontinent to a large degree. Cold fronts often move over these areas and may reach far to the north. The strong ‘Westerlies’are only able to influence the western, southern and south-eastern coastal areas and adjacent interior.

Figure 2: Winter winds over South Africa


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Over the years various studies have been undertaken to quantify South Africa’s wind resource. Dr Roseanne Diab from the then University of Natal published South Africa’s first wind atlas. However this wind atlas based on reviewing good quality that was available from metrological weather stations. The review of this data resulted in broad conclusions being drawn as to South Africa’s wind resource. A meso-scale wind map of South Africa was produced by (Hagemann: 2008) as part of a PhD research at the University of Cape Town. This thesis explores the utility of the MM5 regional climate model in producing detailed wind climatology for South Africa in the context of wind power applications. In terms of the resultant meso-scale wind atlas of South Africa, Figure 3, a significant inland wind resource was discovered over the three Cape Provinces which were previously unknown. Hagemann put forward the case that South Africa’s wind resource is higher than some previous studies have suggested and is comparable to some of the windiest markets in the world. Using remote sensing technologies more detailed meso-scale wind atlases for South Africa are available. One such atlas is shown in Figure 4. From this more detailed mesoscale wind atlas it can be seen that South

Africa has a good wind resource. There are a number of locations with an annual average wind speed of 8m/s at a height of 80m. Meso-scale wind atlases, such as those shown in Figures 3 and 4, are too coarse to be used for planning and evaluation purposes and higher resolution atlases are required, known as micro-scale wind atlases. The micro-scale Wind Atlas for South Africa is described in the next section.

Figure 3: Hagemann’s meso-scale wind atlas

Figure 4: Detailed meso-scale wind atlas for South Africa

Wind Atlas for South Africa

The main objective of the new Wind Atlas for South Africa (WASA) is to develop and employ numerical wind atlas methods and develop capacity to enable planning of large-scale exploitation of wind power in South Africa, including dedicated wind resource assessment and siting tools for planning purposes. The Global Environmental Facility and the Danish Government are co-funding the multiyear project to develop an accurate wind resource map for the coastal regions of South Africa. The wind resource assessment being done by the CSIR, University of Cape Town (UCT), South African Weather Services (SAWS), South African National Energy Research Institute (SANERI) and Risø-Danish Technical University (Risø-DTU).

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Figure 5: WASA domain in blue

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Figure 5 shows the area in blue that has been assessed to form the basis of the new wind atlas. Using meso-scale data and information site selection criteria were developed as to the locations of where the 10 wind measurement masts are to be erected. These sites are representative of terrain types, suitable for meso and micro scale modelling and geographically spread out evenly over the project area. South Africa’s first verified micro scale wind atlas was launched by the Deputy Minister of Energy in March 2012 and covers the area as shown in Figure 6 below. Small wind turbines are a possible option to consider for the provision of electricity for clinics. To determine an optimal system for a clinic the location of the clinic would need to be known and currently the use of Small Wind Turbine’s (SWTs) would need to restricted to the area of the verified wind atlas.

System’s analysis Figure 6: First Verified Wind Atlas for South Africa

Figure 7: Kestrel e400 wind turbine

For this investigation it is unlikely that large multi-MW grid connected wind turbines will be considered. However South Africa does manufacture wind turbines of the size that will be considered to power the clinic. These two major South African manufacturers are: • K estrel Wind Turbines from Port Elizabeth • Adventure Power from East London In 1986 the CSIR designed, manufactured and tested a small low wind speed wind turbine and will be described later. Kestrel Renewable Energy is a subsidiary of Eveready (Pty) Ltd, South Africa’s icon battery manufacturer brand. Kestrel manufactures a range of small wind turbines rated at 600W, 800W, 1kW and 3.5kW, all of which feature robust turbine construction and unique engineering solutions. The Kestrel e400nb has been UK (MCS) certified with pending USA (SWCC) certification.

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Figure 7 shows the largest of the Kestrel wind turbines, the e400 with a maximum output of 3300Watts. This Kestrel wind turbine will be used to further energy

Table 1: Characteristics of the Kestrel e400

analysis for this project. The characteristics of the e400 are shown in Table 1.

Rated output is achieved at the rated wind speed at sea level. Rated power is the optimal power rating of the turbine at the rated wind speed making it maintainable without a cut out wind speed. Rated output is optimised by technology and design, namely by dynamically limiting the output by pitch control. The Axial Flux alternator type reduces the heat losses while energy is being generated in the form of poly phase high frequency output. The full aerofoil blades are moulded from fibre glass and

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protected from dust and moisture. The e400 conforms to IEC standards and follows the provisions in the directives IEC61400-2 (small wind turbines). The power curve for the Kestrel e400 is shown in Figure 8. Applications of the Kestrel e400 in further detail are: • Boost solar and other renewable energy installations increasing productivity, reliability and cost effectiveness. • Water pumping systems with suitable water pump controller to reduce utility costs. • Continual and reliable power for repeater stations, suitable for the telecommunications industry. • Grid tie applications using approved inverters to reduce energy costs. • Generate dedicated power for housing, community and health centres not connected to the national grid. • Small wind farm installations. • Adaptable to meeting many electrical needs. Adventure Power manufactures a mediumsized 300kW wind turbine (Figure 9). This wind turbine is a direct-drive machine, i.e. this wind turbine has no gearbox between the wind-turbine blades and the generator. The variable speed, permanentmagnet multi-pole direct-drive generator is designed to operate the rotor blades at peak performance over the complete range of operating wind speeds. It has a stationary stator and permanent-magnet rotor. The decision regarding the size of the wind turbine of 300kW was influenced by research undertaken by Frost & Sullivan. Frost & Sullivan undertook a study entitled “African Large-Scale Wind Turbine Market” and provided an in-depth analysis of the market drivers, equipment suppliers and industry challenges in the African


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Figure 8: Power curve for the Kestrel e400 wind turbine

wind-power market. In this research, Frost & Sullivan, examined the North Africa and Sub-Saharan Africa regional wind-power markets. The research focused on the following segments of the large scale windturbine market: 100-600kW, 660-850kW and greater than 850kW. Despite its potential, the African wind-turbine market is yet to contribute significantly to the power sector in the continent. Historically, the low price of electricity generation from traditional feedstock such as coal and natural gas has limited the interest in renewable-energy power generation. However, higher-thananticipated economic growth in African states in the last five years has led to a rapid increase in electricity demand, along with a renewed interest in alternative forms of power generation. “As a result of public pressure to provide reliable power supply, governments in Africa are investing more time and resources into exploring renewable energy for power generation,” says the analyst of this research. “The success of the wind-power market in Europe and the United States has convinced many governments that wind power can assist in alleviating some of the power shortages in the African continent.”

The energy crisis of the 1970’s stimulated interest in power generation by means of wind turbines. A programme for the research and development of wind turbines for generating electricity was launched by the CSIR. The objective of this research programme was to develop small-scale wind energy conversion systems intended for operation in regions with low average wind speeds (Esterhuyse, 1986). This was to compliment the then existing machines that were designed to operate in much stronger winds. The main objective of the programme was therefore to develop a wind turbine (Figure 10) that could operate continuously in regions with low average wind speeds, such as in Pretoria that has an average annual wind speed of 1,8m/s. From the results of tests done on the full scale wind turbine it was shown that a turbine rotor could be designed for effectively harnessing the wind energy in regions with very low average wind speeds. This programme also proved that a wind turbine could be built from locally available parts to produce an attractive source of energy suitable for application in the underdeveloped regions of South Africa.

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Figure 9: Adventure Power’s 300kW wind turbine

Feasibility Correct sizing

For purposes of this project the electricity consumption for a typical clinic was estimated at approximately 20 kWh/day. The Kestrel e400 wind turbine was selected as the wind turbine around which a hybrid wind/PV system will be designed. Within the context of this project where clinics are located in windy areas a configuration that can be considered is to combine PV with wind turbines.

Installation requirements

The full installation requirements could not be determined at the time, but once the full system was designed the installation requirements would be completed. However it should be noted that Kestrel’s preliminary quote for the East London IDZ site did not make use of PV panels but two Kestrel e400i wind turbines. Eveready Diversified Products who manufacture the Kestrel range of small wind turbines were approached to provide

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Figure 10: CSIR’s low wind speed turbine

a quote and sizing for a wind PV based system for the East London IDZ. This was done to get a cost and correct sizing as a reference point for a wind/PV hybrid based system for the clinic where the wind resource is good. Kestrel quoted for a 24 hour battery backup but this can be extended to any autonomy necessary. If 20 kWhrs/day is not exceeded this should not be necessary. Also quoted for are 12 Volt deep cycle lead acid batteries could be replaced by the higher performing 2 and 4 volt solar cells if needed. However, it should be noted that for this site Kestrel’s preliminary design requires no PV panels and that two small wind turbines generate electricity.

Payback period

Preliminary enquiries suggest that the cost of a 20 kWh/day wind based system for a clinic located on the East London Industrial Development Zone is R287 854.56 inclusive

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in association with

 BEST ARCHITECTURE SINGLE RESIDENCE SOUTH AFRICA A South African Home For Art by Mellet & Human Architects


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of VAT. The payback period can only be calculated when firm cost figures have been obtained: however at current rates and projected rate increases the likely payback period is 20 years.

Conclusion

Small Wind Turbines are an option to be considered in particular in those regions where the wind resource is known to be good. The cost of a 20 kWhr/day PV system for a sunny but wind poor location such as CSIR Pretoria campus ranges from R291 718.00 to R319 000.00 inclusive of VAT and requires 48m2 of PV panels. The cost of a 20 kWhr/day wind system for a windy location such as the East London Industrial Development Zone is

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R287 854 56 inclusive of VAT and requires 2 x 3000W wind turbines. Preliminary investigations indicate that a wind system is slightly cheaper than a PV only system, but is site dependent on the availability of wind and solar resources. In the short term the following three options are recommended for the clinic to function off-grid: • Photovoltaic (PV) based system for the generation of electricity for sunny but wind free sites such as CSIR Pretoria campus. • Wind based system for the generation of electricity for windy sites such as the East London Industrial Development Zone. • Liquid Petroleum Gas (LPG) for heating and cooking.

References • • •

Esterhuyse J.C. 1986. Harnessing the wind using axial flow wind turbine. Pretoria: CSIR Research Report 619, ISBN 0-7988-3775-6. Hagemann K. 2008. Mesoscale Wind Atlas of South Africa. Thesis presented for the degree of Doctor of Philosophy, University of Cape Town. Szewczuk S.; Markou H.; Cronin T.; Lemming J.K.; Clausen, NE. 2010. Investigation in to the Development of a Wind Energy Industrial Strategy for South Africa. Pretoria: CSIR. Prepared for the UNDP.

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CASE STUDY

HOUSE DU PLESSIS MIDSTREAM RETIREMENT VILLAGE

This house, designed by Mellet & Human Architects, is situated on a corner stand of 600 square meters in the Retire@Midstream Village of Midstream Estates, a development with typical Highveld climate: Cold winters and moderate summers. Views are afforded to the southeast, and an existing house borders to the north. The brief from the client was to design an energy efficient, low maintenance, and private retirement house. Estate architectural guidelines had to be followed, with living areas flowing to the northeast of the stand, and an allowed maximum coverage of 50%. The resulting design makes full use of the coverage guidelines. The house is compact, and maximizes on northern exposure. A central living space connects the private bedroom wing, kitchen, outside living space, garage and staff room. No space is wasted, folding doors connect outside and inside living areas, and no passages or steps are found. Clerestory windows in the high volume rooms allow sunlight into the house. These windows are remote controlled to open for ventilation, and rain sensors automatically close them in rainy weather. The pitched roofs along an east west orientation provide sufficient surface for solar

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panels. The concrete roof links collect rainwater, and provide sun protection over windows and doors. The house envelope is completely insulated with high density polystyrene insulation in the floors, cavity walls and ceilings and on top of concrete roofs. Double glazed, UPVC windows and doors are used. The heated lap pool has remote controlled pool cover in order to retain heat. Energy efficient LED lighting is provided through downlights and recessed strip lighting. Cooking is done with a gas hob and braai, and all kitchen appliances have low energy usage. The exterior has low maintenance finishes of face brick, natural


CASE STUDY

Hot Water

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Floor plan stone, Chromadek roofs and uPVC framed windows. The water wise garden has plantings of succulents, extending onto the pavement. Grey water is recycled for use in the garden, as well as flushing of toilets. Kyasol Green Building Solutions was approached by the architects to provide the following practical energy saving solutions for the house:

Rainwater Rainwater collected from the roofs is stored in 3x 6500l rainwater storage tanks with automatic municipal switchover and 5000l water back up capacity at all times. Filter rinsing is automatically or manually triggered. The rainwater is treated through an ozone unit to drinking water quality and supplied to all consumers in the house.

A 500l storage tank is heated by 10square meter high performance flat collector panels on the roof. Back up is provided by a heat pump and 2.3kW submersible heating element. Insulated warm water is ring fed throughout the house with timer pre-heating at peak times in the mornings and evenings, according to set temperatures. Excessive heat from solar heating is diverted to the pool for heating purposes.

Heating and cooling of the house In total 190square meters under floor water heating is provided insulated by 50mm thick high density polystyrene underneath. Water based wall hung air handling units are installed in the living areas and bedrooms used for cooling or as heating booster, powered by a 14kW heat pump. This heat pump also acts as backup for hot water in case of insufficient solar radiation.

Photovoltaic panels 22x245W polycrystalline photovoltaic panels supply +- 5.4kW to all consumers in the house. A total of 28kWh battery storage supplies essential appliances with power during power outages or at night. This system is optimized for self-consumption, but backed up by the power utility.

Home automation Light switching, and creation of scenes is via wireless EnOcean switches or via cellphone app. The automation also sets temperatures in the rooms, switches the heat pump to different operational modes, controls the level of rainwater tanks, and controls pool pump schedules.

1. Street elevation with waterwise pavement garden visible; 2. Pool courtyard with solar panels, double glazed windows and clerestory windows visible; 3. 3 500l buffer, 14kW heat pump and back up batteries THE GREEN BUILDING HANDBOOK

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ENERGY PERFORMANCE CERTIFICATES FOR BUILDINGS

Dr. Rodney Milford, CIDB


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S

ANS 1544 (2014) Energy Performance Certificates for Buildings, has recently been published by the South African Bureau of Standards (SABS), and sets out the requirements for producing energy performance certificates (EPCs) for buildings that compare the energy performance of a building to the maximum energy consumption values contained in SANS 10400-XA (2011) The Application of the National Building Regulations, Environmental Sustainability, Energy Usage in Buildings. The Standard is applicable only to: • the energy performance of buildings based on measured energy consumption; • existing buildings that have been in operation to meet a particular need associated with the use of the building for two years or longer, and that have not been subjected to a major renovation or change of occupancy within the year before the assessment period; and • building occupancy classes considered in SANS 10400-XA for which the maximum energy consumption is specified in SANS 10400-XA. EPCs are commonly used around the world for driving energy efficiency in appliances, motor vehicles and, more recently, for buildings. An impetus to the use of EPCs for buildings in Europe and around the world was outlined in the European Directive 2002/91/EC, which requires that: • “Member States shall take measures to ensure that for buildings with a total useful floor area over 1 000 m2 occupied by public authorities and by institutions providing public services ... an energy certificate … is placed in a prominent place clearly visible to the public”; and • “The energy performance certificate for buildings shall include reference values

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such as current legal standards and benchmarks in order to make it possible for consumers to compare and assess the energy performance of the building.” EPCs are used extensively around the world as a mechanism: • to focus on energy efficiency within buildings; • to benchmark the energy performance of a building against industry benchmarks or national norms; • for establishing a register of information on energy performance of buildings, which can be used: • to support policy development by government; and • support retro-fitting programmes by building owners and operators. EPCs in South Africa are aligned to the Department of Energy’s National Energy Efficiency Strategy, and an official request was sent by the Department of Public Works in August 2012 for SABS to establish a sub-committee on Energy Performance Certificates for Buildings – with an intended strong focus on government buildings. The sub-committee was established as part of SABS TC59/SC 01 Construction Standards - Energy Efficiency and Energy Use in the Built Environment. The work of the subcommittee received a major impetus when the South African-German Energy Program (SAGEN) of the German International Cooperation Agency (GIZ) sponsored a study tour to Germany in September 2013 to obtain first-hand information on the use of EPCs in Europe. The study tour visited, amongst others, the German Energy Agency (DENA), the EfficiencyHouse+ in Berlin, the city of Frankfurt, and the KfW Promotional Bank, Frankfurt. The study tour included representatives from the Department of Energy and of Public Works, the cidb,


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SANEDI, SANAS, the GBCSA and the South African Institute of Architects. The study tour was led by Christian Borchard of GIZ, and has had a major impact on SANS 1544, and continues to have an impact on the roll-out of SANS 1544.

ENERGY PERFORMANCE CERTIFICATES

regulation or a policy directive will be issued by government in 2016 requiring EPCs to be displayed on public buildings owned and leased by the public sector. While the details are still being finalized, consideration is being given to requiring all government buildings of an occupational category that is covered by SANS 10400-XA and with a total net floor area of over 1000m2 will be required to display an EPC in a prominent place that is clearly visible to the public. In terms of SANS 1544, the EPC would be valid for a period of 5 years.

The Standard for Energy Performance Certificates

Figure 1: Sample UK home performance rating energy efficiency label Transferred from en.wikipedia; transferred to Commons by User:Magnus Manske using CommonsHelper.

The publication of SANS 1544 is the beginning of a process that targets energy efficiency in buildings â&#x20AC;&#x201C; and is being led by the public sector. It is intended that

EPCs record the net energy consumed within the building in kilowatt hours per square meter of net floor area per year (kWh/ m2/a), and SANS 1544 requires the energy use over a period of 12 calendar months. SANS 1544 then compares this energy use against the maximum annual energy consumption per building classification for each climatic zone provided for in SANS 10400-XA â&#x20AC;&#x201C; which is a measure of how efficient the building is. It is recognised however that EPCs include measured energy use arising from plug-loads (including PCs, dishwashers, portable air-conditioners, etc.), whereas the maximum annual energy consumption specified in SANS 10400-XA excludes plug-loads. SANS 1544 includes rules for including different energy mixes, multiple occupancies, unoccupied floor areas and excluding energy used by garages, car parks and storage areas as well as energy consumed by outdoor services (for example landscape lighting and security).

Driving Energy Efficiency through EPCs

EPCs measure the energy consumption of a building (in kWh/m2/a, including plug-loads), and compares this against the

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quality finishes International

Marcoatings International was granted an exclusive Marmoran International Applicator Licence to ‘Supply & Fix’ Marmoran Customised Wall Coating Systems through out the African continent and abroad. What makes these’ Quality finishes’ not only aesthetically pleasing but they are formulated for a specific compatibility with most construction materials and dealing with extreme climatic conditions on the African continent. Our Marcoatings range of quality wall finishes, with more than 40 different specialised textures are all water based and enviromentally friendly. Marcoatings Internationl is making strong inroads into West Africa, having completed several Prestigious Projects in Nigeria, with current projects still in progress. Marcoatings International works closely with Marmoran assuring clients locally and all over the African Continent and abroad of receiving not only world class Specialised wall coating systems from Marmoran, but also engaging our Marcoatings International Licensed Applicators & Project Management teams to these different countries to carry out work on the many prestigious projects throughout the continent and abroad. Marcoatings offers a TEN YEAR INTERNATIONAL GUARANTEE on all Customised wall coating systems supplied & fixed by Marcoatings International. We pride ourselves, being associated with some of the finest wall coatings in the world, Being able to supply the Marmoran range directly to the customer, architect & developer. Marcoatings is able to advise on all Marmoran Specification as well as shipping & clearing. Contact us Telephone: Mobile: Email: Website:

00 27 21 686 4225 00 27 79 917 7799 info@marcoatings.co.za www.marcoatings.co.za


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ENERGY PERFORMANCE CERTIFICATES

Figure 2: SA Energy Performance Certificate

maximum allowable energy consumption of a new building as specified in SANS 10400-XA (excluding plug-loads). The EPC then becomes a management tool, and provides the building owner or lessee with information to: • select which buildings to lease; • benchmark the energy-efficient performance of buildings; • prioritise buildings for energy-efficient retrofitting; and • identify and monitor energy-efficient cost savings. All owners and operators of buildings are encouraged to adopt and implement EPCs as a management tool to support energy efficiency.

The Building Energy Performance Register

It is envisaged that a national Building Energy Performance Register will be established by the South African National Energy Development Institute (SANEDI) to record all valid building energy performance certificates. This will then establish a

national register of energy use of buildings (in kWh/m2/a), for different occupational categories, in different climatic zones, and by age of building or age of major retrofit. The Building Energy Performance Register will be key to monitoring energy efficiency trends, and to provide a feedback loop into the maximum allowable annual energy consumption provided for in SANS 10400XA. In this regard, aligned to the NDP and to National Energy Efficiency Strategy, the Building Energy Performance Register will in monitoring the trajectory towards ”zero carbon buildings” that is currently being developed by the SABS Committee 59G WG4 Targets (see illustrative example below).

Timelines for Introducing EPCs

To comply with SANS 1544, EPCs must be issued by organisations accredited by the South African National Accreditation System (SANAS) or by a member of the recognition arrangements of the International Laboratory Accreditation Cooperation (ILAC) or the International Accreditation Forum

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PROFILE

PRODIGIOUS

Cost efficient eco-construction ahead

Prodigious Construction and Property Development Consultants is a medium sized quantity surveying firm based in Cape Town. The company is recognised for eco-friendly sustainability and their understanding of an urgent need to lower environmental impact. This has seen Prodigious integrating advanced technological energy saving solutions such as Photovoltaic (Solar PV) systems and Radiant heating solutions to their latest projects. Radiant heating solutions can be used in all commercial and residential properties and, as such, has been included in all projects undertaken by Prodigious where possible. Different applications of the system which uses convection and radiation to exchange heat through temperature-controlled surfaces with their surrounding environment, are tailored to each project to ensure lowest energy consumption at all times. In addition to installing Radiant heating and cooling systems, Beau Constantia Wine Farm as well as a private residence have implemented a usable solar power supply and energy saving solution by means of Photovoltaics. This substantially decreases the clientâ&#x20AC;&#x2122;s main grid electricity consumption and costs. In addition,

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it safeguards against main grid power failures. Solar panels are installed on the roof and provides the source to convert sunlight into electricity, which is then stored in a battery back-up. This ensures uninterrupted full back-up power for up to 6 hours. The system is fully controlled by the user through online monitoring software. The plans and construction of Pearl Valley Golf and Country Estate also include the use of a grey water recycling system, which markedly reduces water consumption. Due to the need for relatively high water use, the system not only has a positive impact on the environment but drastically reduces costs and protects the Estate from water restrictions imposed during very dry seasons. Prodigious Construction and Property Development Consultants has accomplished experience and offers a comprehensive range of professional property consulting services. Their main aim is to provide cost-effective and efficient turnkey quantity surveying services. Implementation of environmentally efficient systems in all their projects have earned them a good standing within the industry for providing cutting-edge, sustainable ecological solutions to new and existing urban developments and housing projects.


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ENERGY PERFORMANCE CERTIFICATES

Figure 3: Energy efficiency trajectory Source: GIZ/Warren Gray

(IAF). In support of this, SANAS has initiated a programme to develop the necessary criteria for accrediting organisations which will be complete by around March 2016. Conformity assessment bodies are encouraged to follow these developments and to be ready to be accredited to issue EPCs in line with SANS 1544 by early 2016. Furthermore, two organisations have already initiated the development of training material for assessors to issue EPCs, which will be available from July 2015 onwards. Organisations and individuals that are interested in issuing EPCs are encouraged to follow these developments and to participate in recognised training opportunities from around the third quarter of 2015 onwards. Further training providers are also encouraged to participate in the process, but will need to align their training processes with the requirements of SANAS. Finally, it is anticipated that regulation or a policy directive will be issued mid-2016 requiring buildings that are owned or leased by government to have an EPC within two

years of the regulation or a policy directive coming into effect.

EPCs for the Commercial and Residential Buildings

As is required in several countries around the world, consideration is also being given to introducing requirements for EPCs to be displayed on private sector commercial buildings, on change of ownership or on a substantial change in lease agreements. It is possible that such requirements could be introduced from around 2020 onwards, but the private sector is encouraged to adopt EPCs as soon as possible. EPCs are also a very effective tool for managing and driving energy efficiency in the private sector. Consideration is also being given to developing a national Standard for EPCs for residential buildings, and for introducing requirements for EPCs in residential building upon change of ownership or change in lease arrangements. These requirements are currently being considered by the relevant SABS committee.

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ALEXANDER FORBES A case study

Developer: Zenprop Property Holdings Tenant: Alexander Forbes


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CASE STUDY: ALEXANDER FORBES BUILDING

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he new Alexander Forbes head office at 115 West Street Sandton, replaces the existing head office for Alexander Forbes which is currently spread over two buildings on Katherine Street and Rivonia Road. Alexander Forbes needed to consolidate with better use of space for 2500 people; this involved modernising work facilities and upgrading technology services. Considering its status as a renowned financial services company, these needed to be state of the art, with added security.

Construction & Design

The design warranted a flexible building hence the large floor plates, punctuated by two atria to maximise the natural daylight into the office spaces. The north-west orientation of the site also influenced the design with the powerful scallop elements to capture north and south light and protect the inhabitants from east and west light. The atrium captures natural light which floods from the top down and from each side. It was designed to create a park like environment with the introduction of 6m high Ficus Benjamina trees, sunken into the floor. A wide variety of natural materials were used including bamboo veneer and wafer thin slate stone to clad the organic pods.

Facilities

The project is essentially an office building but includes a wide variety of staff facilities including: a crèche, a gym, 6 parking levels, smoking rooms (in a basement with separate ventilation, was required because of current smoking regulations) prayer rooms for Muslim and Interdenominational faiths; a beauty parlour, a health studio with a physiotherapist, a 200 seat auditorium, state of the art AV meeting rooms, a multipurpose

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room; staff training rooms, a fully integrated caterers kitchen and canteen, coffee shop, bar and wine cellar.

Special Features

This is Paragon’s biggest Green Star project and has been accorded a 4 star Green Star Design V1 rating. This had a profound impact on the architectural design. Other work style elements that influenced the project included: the efficiency of floor plates and a flexible work environment which allows for ‘churning’ (the ability of a space to adapt to flexible sizes and working conditions). Internal circulation was considered in two further areas, viz. the introduction of escalators (although this cost 1/3 of a Green Star point) to encourage staff moving between floors, not to use the lifts; and the splayed bridge links ensure optimum travel distances between the floor plates. The building features a total construction area of 100 000m2 with a 37 500m2 rentable area and a budget of between R700 million and R1 billion. The building incorporates some 1800 parking bays over 6 basement levels, plus 140 bicycle bays, with shower facilities and preferred bays for car pooling and hybrids. Construction on the project began in mid-February 2011, and practical completion was achieved on 17 September 2012. Slightly ahead of the originally scheduled 30 September 2012. The architectural design is characterised by a number of elements: • The skylights are made up of 12 giant cones. They are 8.4m in diameter and float above the atrium space like giant clouds. The forms continue to the outside of the off-shutter concrete roof. They were required to introduce vertical light and their sizes and shapes were generated through Revit to maximise their performance balanced with cost.

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Two prototypes were developed, which were then rotated to generate 12 cones. They were manufactured off site in M1 (material: high grade gypsum reinforced with glass fibre for a very high strength); they are self-supporting; about 10mm to 50mm at the ribs, skimmed and painted. They were cast off a master mould in 8 pieces to facilitate transportation and then re-strung in the atrium space and tied back to the roof structure. • Scallops clad in Rheinzink, constructed from a concrete structure which generated the form, clad in a timber (German pine imported 22 x 110mm) sub-structure and then clad in Rheinzink with a vertical standing seam. This naturally ages over time, oxidises, and takes on a blue-grey colour. • Vanities: The central ablution core is required to cater for the floor plates of 4500m2, which is fairly large and requires a high number of bathroom facilities. The bathrooms were conceived as open spaces with minimal hindrance and articulated with a calm interior. This was expressed with a simple black and white

CASE STUDY: ALEXANDER FORBES BUILDING

colour scheme and drawing a single point of focus to the single vanity and mirror. The intention being that fittings would fade visually away. WC cubicles are simply Duco sprayed white against painted white walls. The vanities were constructed from a Corian steel framed structure which was generated in Revit, and hung from the black porcelain tiled wall. • The off-shutter concrete columns are one of the architectural features of the atrium. The columns are 8.5m high, raked and moulded in a single cast; based on specialised formwork that was generated in Revit and Structures; exported in AutoCAD.dwg format to the sub-contractor for construction. Sizes were specified by the engineer and then sculpted by the architects. There were two types: a Y-shaped branch that supports the cantilevered walkway and one that is simply supporting. • Water features in the atria: Reflecting black ponds are clad in 5mm porcelain tile, it was important to achieve a precise level at the rim thus meeting pods on the

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northern side, so when in the meeting area, the sensation is one of floating. • Steel bridge links & roof structure: these are Wishbone shaped in plan to link the north and south blocks across the atrium. They span 22m and are suspended off the roof trusses by 16mm diameter solid steel rods. Due to a tight construction programme, the bridges had to be hung from temporary steel columns, once the roof structure was in place, the bridges were suspended from the trusses, the columns were later removed. Self leveling connecting bolts were used to re-align the steel, once the full load was transferred to the roof structure. • Glazing: integral part of the Green Star calculations. Approximately 22 000m2. An important balance between light and heat loading. All double glazed except the atrium, roughly 8 types of glazing specification, in various combinations. • Landscaping and planting: decking ground floor north and south, fully

CASE STUDY: ALEXANDER FORBES BUILDING

planted, planter walls are constructed from off shutter concrete, which create pockets of meeting areas. • Integrated motorised blinds in the meeting pods on the ground and first floor face north-west and the glass slopes at 67.37° design feature. Internal rectilinear and ‘spinnaker’ shaped blinds are operated manually by a remote control whilst externally the Ferrari fabric vertical blinds are controlled by a sun and wind sensor to ensure shading internally without compromising safety and structure. • Product and material specification: Bamboo, a widely used renewable material, was used throughout the project. Low VOC (volatile organic compound) paint was also used extensively. Whilst this may not initially be noticed, the absence of a new chemical smell, would have been. • Water recycling: All the grey water from the basins and showers is harvested and

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ECO-CRETE Concrete by its nature is not Eco-friendly by any means! Have you ever driven past a cement quarry or processing plant, quarry in itself indicates nonrenewable resources being consumed. There are many other building materials that are renewable but none are suitable for large constructions, buildings etc. There are however ways we can reduce our impact on the environment. All the cement manufacturers blend their lower grade cements with pozzolans, such as fly-ash and silica fume to produce a lower cost, lower strength grade of cement. But this does not always work with high strength requirements of the building industry. We at The Concrete Company have specialised in the manufacture of decorative concrete products, coloured floor screeds, overlays, polished concrete floors and polished concrete counters. In the process of developing our counter systems we along with Textile Concrete Consultants have developed a systems where we can not only make our counters thinner but stronger and in the process use substantially less virgin material. Only our face coats are made with sands, our backing is a blend of cements some chemicals and purely pozzolans. This produces a 15 â&#x20AC;&#x201C; 20% lighter concrete that is on average 50Mpa that even after cracking still retains its strength. Overall we product counter tops from up to 70% recycled material. We can apply the same possolan material to our floors, replacing up to 50% of our sands and aggregates with the recycled material yet retaining the overall strength of the concrete floor. Recycled material does however not mean less expensive as the sources of these products are often remote and need to be transported fair distances.

www.theconcretecompany.co.za â&#x20AC;˘ 0748916217


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treated with enzymes to be combined filtered rainwater which is used for plant irrigation and the flushing of urinals and WCs. â&#x20AC;˘ Passive space heating and cooling. The system is a chilled water fan coil system which is structured as follows: 60% of the cooling is by water-cooled chillers for maximum efficiency; 40% of cooling is by reversible (heat pump) air-cooled chillers for water independence and winter heating. High Greenstar fresh air rates are preconditioned using indirect evaporative precooling in summer and heat pump heating in winter. â&#x20AC;˘ Atrium Conditioning: The atria have a separate air conditioning system. In summer hot air that collects at the top is discharged to outside and replaced with fresh air which is indirectly precooled through evaportion. In winter the hot air that collects at the top is ducted down to heat lower levels in a desertification process. While under fire conditions smoke is extracted from the atria.

CASE STUDY: ALEXANDER FORBES BUILDING

Challenges faced during the construction of the project

A very tight construction programme, featuring parking bays which are 100% of site, left little to no room to work. This impacted on the sequencing of construction which was impeded. To this end a construction ramp was used; but fortunately an adjacent site could be used for batching plant.

Making a lasting impact

Alexander Forbes encourages staff to recharge their energy by using the colourful break-out spaces on every floor. Bins are provided here to change the mindset regarding recycling. To this end print stations have recycling bins for paper. A gymnasium has been provided and in the parking areas, preferential bays are provided for fuel efficient/hybrid and car pooled vehicles. Cycle bays are also provided. All of these design considerations are important not only for their impact but also to change societal mindsets for the future as we grapple with energy and resource shortages.

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PUSHING THE BOUNDARIES AND EXCEEDING EXPECTATIONS A Case Study: 102 Rivonia

By Boogertman + Partners Architects


T

he new headquarters for Ernst and Young, developed by Eric Property Group and designed by Boogertman & Partners has been a unique addition to the new Sandton skyline. With all the new development happening in the Sandton’s golden mile, Boogertman have truly designed a user centred productive work place for its occupants by using flowing organic spaces that encourage people to circulate and interact and in turn creating a spectacular design feature. Modern architecture has become tremendously challenging; aesthetics need to be married with practicality, build ability, budget, time constraints, tenant requirements and sustainable principles in a package that satisfies many different stakeholders. Boogertman, backed by the professional consultant team, pushed the boundaries to deliver a 98 800m2 4 Star Green Star SA quality product to be known as 102 Rivonia. EY required 102 Rivonia to not only function as a work space but to reflect EY culture of integration, professionalism and excellence and to live “Quality in Everything We Do”. The building comprises of organic shapes and curves, with no one floor similar to another, married together with the use of glass and metal and finished off with timber. The offices space offered by 102 Rivonia is a reflection of the workplaces of the future and meets the requirements of their high profile tenants with accessibility to major transport networks (including Gauteng’s prestigious Gautrain and Rapid Bus transit lane), visibility, large floor plates, flexible & efficient work space and closer proximity to local amenities. The site encompasses 3 identifiable elements; a 9 level parking basement structure with 2 buildings on top of the main podium. The precinct is designed to encourage the mixing of people with the use of the main podium where pedestrians gather from the parking levels below and the grand stair case


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off Rivonia. The EY building, Tower Block 1, located on the eastern boundary comprises of 7 levels and the multi tenanted building, Tower Block 2, located on the western boundary compromises of 14 storeys. Tower block 1, the shorter tower and the new headquarters of EY, has an active atrium space with transaction stair and bridge links. Tower block 1 and 2 are connected on 5 different levels offering a link between both buildings allowing for future flexibility of its anchor tenant.

The Design

Individual and unique floating floor planes create overhangs and protrusions, enhancing the organic relationship between the façade and the horizontal movement of the spaces. In order to create such vertical fluidity, a unitized glass façade was adopted and complemented by vertical fins rotated at 3 degree increments around the entire external face. These fins to ensure the maximum natural light enter the space but minimal solar heat warms the space. The façade was constructed from a unitised high performance double glazed glass unit with a light tint, allowing for an ease of assembly and at the end of the building’s life an ease or possible reuse/repurpose of the unitised glazing. As previously mentioned the 102 precinct was designed to be people centric as a building need to work for the users. EY where committed to the design ideology and conducted Workplace Audits to understand how their workforce functions. This insight led to the development of solutions and creation of new work settings that would better support the staff’s actual work needs. As much of the staff is a mobile workforce it made sense to utilise an Activity Based space planning philosophy. An Activity Based Workplace provides more (more facilities, more variety,

CASE STUDY: ERNST AND YOUNG BUILDING

more amenities) to enable people to more effectively undertake their work where a variety of spaces are provided, that give staff a choice of where and how to work depending on the work task requirements. The ratio and type of space was informed by research on EY’s work habits combined with future needs. It can be noted that in most areas, from the Work Café to Pause areas, staff have access to power and WiFi so that they can focus in solitude or brainstorm with colleagues. Sustainable space planning initiatives included maximising access to natural light and views by keeping built zones away from the perimeter. Glazed partitions to meeting rooms rather than solid partitions have been used wherever possible and in training areas walls are operable so that spaces are flexible and dynamic. Acoustics have been considered with noise minimisation features on the open floors. These include using sound absorbent materials wherever possible. Carpet, fabric workstation screens, acoustic ceiling tiles, suspended acoustic panels and padded wall treatments have been used in more collaborative areas where there is a denser population and therefore higher noise levels. Use of planting, specification of furniture and selected finishes, including low VOC paints, create a harmonious and healthy work environment. The architect and space planner made clever use of dematerialised surfaces to differentiate space use. For example, exposed polished concrete flooring was used for the high traffic circulation areas around the atrium and adjacent to the lift core and columns were left unclad and unpainted reducing the need for materials and reducing the carbon footprint of the project.

Building Systems

Although floor plates are large, they are divided strategically with the atrium (and

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various walkways/bridges/links) and different space uses, open plan/meeting rooms resulting in all of the office being expose to natural light. Utility areas and meeting spaces are located close to the core, ensuring that at least 60% of the office open plan area has unhindered line of site views to the outdoors. The blinds in EY are automated and are programmed to close when direct solar glare is experienced on a particular faรงade. Due to the amorphous design of the building, sixteen different zones are identified and programmed into the automated blind motorisation system. The automation assists in maximising the natural light but maintain a comfortable working space. WSP were responsible for the Electrical and Electronic design for this project. The lighting is controlled throughout the open plan offices with occupancy sensors, zoned to control switching to areas not exceeding 100m2. Smaller rooms and media rooms have individual switches. All the the office spaces maintain a lighting power density less than 2 W/m2/100 Lux. The building management system (BMS), which monitors and controls all electrical equipment via meters, serves as early warning signal to high energy consumption or areas with excessive usage. Meters monitor the energy usage for each floor for power, lighting, HVAC and UPS power. With these efficient system features the building is designed to be approximately 50% more efficient than the notional building of the same size as defined by Green Star SA Office v1, with a reduced energy reduction of 214.7Kwh/m2 per annum. Within the EY Tower, fresh air is distributed through the access flooring to users where they are situated and not mixed with warmer air as traditionally done the increased fresh air rates maintain the general airborne contaminants at concentrations

CASE STUDY: ERNST AND YOUNG BUILDING

below exposures that have potential to cause adverse health effects to a substantial majority of occupants. The HVAC systems consist of 3 air-cooled chillers located on the roof. Primary & secondary pumps are used to circulate the chilled water to decentralised air handling units on each floor. Insulated supply air ducts and variable volume controls supply air to the office spaces. The air is controlled through a wall mounted set point adjuster, allowing occupants to adjust the desired temperature set point. Water is a precious resource and as a result, rain water is harvested and stored in tanks located in the basements. Separate pipes supply rainwater to toilets and urinals for flushing thereby decreasing consumption of high grade potable (clean drinkable) water. Water-efficient sanitary fixtures have also been installed throughout the building. Further reducing the amount of portable water required, as a result discharges less water to the sewerage system. An estimated 0.57L/day/m2 is discharged to sewerage, adding less strain on existing infrastructure. Similarly the fire system testing in building is typically responsible for millions of litres of water wasted due to weekly routine pump, now up to 98% of the water used in routine testing is recycled back into the storage tanks and this allows for a saving of millions of litres of water, per annum. A further water conservation design element for the active fire protection systems (sprinklers) is that isolation valves are fitted on every floor to allowed individual draining on each floor. This means that in cases of malfunction/ office churn only the relevant floor can be tested and drained without draining the fire system for the entire building.

Construction

Construction commenced in June 2012 and the building had to be ready for operational occupancy by November 2013

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PROFILE

G-FLOW GREY WATER RECYCLING Setting New Standards For Grey Water Recycling Systems As South Africa becomes more environmentally aware, there has been an increase in ‘green’ technologies and grey water recycling is no exception. The affordable, award Winning Grey Flow Grey Water systems have set a new standard for grey water recycling by automatically (and safely) irrigating up to six different watering zones in your garden via a state of the art drip line and rotor irrigation controller. While fresh water is quickly becoming a scarce commodity, grey and recycled water resources are fast becoming very popular options for reuse in the garden. Installing a grey water system will save municipal water and keep your gardens green. International standards in many countries recommend using a drip line irrigation system with grey water and not a sprinkler system. This is in order to prevent any germs and bacteria that may be in the grey water systems from getting airborne or settling on top of the lawn and garden. Most standard drip line as well as irrigation systems are not designed for use with grey water and the emitter/spray nozzles often clog rendering the grey water system ineffective. The manufacturer of the Grey Flow systems have overcome these problems and designed a robust and reliable grey water unit and drip line irrigation system.

The Grey Flow Advantage The manufacturer of the Grey Flow system has spent the last 8 years developing an affordable, safe, clean, low maintenance, robust and reliable grey water drip line irrigation system that meets the most stringent environmental health and safety requirements. The Grey Flow system’s drip line and rotor (irrigation controller) have both been specifically designed for grey

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water use. The drip line is self cleaning and has a turbulent flow path. The vortex, thermally protected pump and side mounted float switch have also specifically been designed for grey water use. Ensuring years of trouble and clog free watering. The Grey Flow systems are fail safe with an automatic diversion to the sewer during power outages. The Grey Flow systems are supplied with a 3 way manual valve for gravity diversion to the sewer when the system is not in use. The systems come with an innovative self drain and auto de-sludge mechanism. The Grey Flow systems have won various awards overseas as well as locally. They have been awarded a ‘commendation’ at the Eco Logic awards (hosted by SABC3 and the Enviropedia) as well as ‘The Most Innovative Product’ at The Green Expo in Sandton. The systems have Smart WaterMark certification & WaterWise approval.

Tel: 044 3824887 Email: marc@watercon.co.za Website: www.watercon.co.za


14

for EY. Added to this tight programme were the unforeseen and problematic soil conditions, transport strike, NUMSA strike and a complex architectural design. Eris Property Group challenged the professional team with an absolute deadline and this forced consultants to opt for out of the box thinking and set new benchmarks for the speed of construction for contracting team. Added to the pressure Murray & Roberts had to comply with strict Environmental Management Plans (EMP), Waste Management requirements, CIBSE & ASHRAE commissioning standards and Hazardous Materials audits and safe removal as required by Green Star SA Office v1. A waste management plan was implemented to reduce the amount of construction and demolition waste going to landfill and the project managed to divert at least 70% of the waste from landfills. Additionally, all the reinforcing steel was specified to have a minimum post- consumer recycled content of 90% or higher and at least 50% of all timber uses was sourced from Forest Stewardship Council Certified suppliers. At the peak of construction over 1,000 construction personnel and sub-contractors were active on site. Murray & Roberts have continued to break new ground with the use of concrete with low Portland cement content. The building required more than 40,000m3 (16 Olympic swimming pools) of concrete and had to be completed within an 18 month deadline. In addition to this goal being achieved, the project succeeded in reducing the absolute quantity of cement by more than 30%. The concrete used has 30% fly ash, which is a recycled by-product from coal-burning power stations for which there is usually no use. Not only does the process require less ordinary cement (with a

CASE STUDY: ERNST AND YOUNG BUILDING

high carbon foot print) it is environmentally friendly, and the concrete can gain higher strengths. Speed of build was assisted by adoption of a typical construction method. The building was finished from the bottom up, with no ‘bird cage scaffolding’ allowed on the external façade or in the atrium. This was not only to save time with the assembly and dismantling of the scaffolding but also the scaffolding restricts access to the areas below. This in itself presented challenges and had to be part of the design considerations for these areas. Typically, buildings structures go up and they are then finished from top down. 102 Rivonia’s finishes followed the wet works, i.e. there was still wet works being carried out on the top floors whilst finishes were being installed on the floors below. This allowed for the tight program to be achieved and for areas to be completed as the building topped out.

Conclusion

In the end it came down the right people and team in place. A team that was solution –focused that pushed funding, aesthetics, design and innovation borders. Drawing on WSP’s global experience and in depth local knowledge we take a holistic approach to green building design. We take into account the whole life-cycle of the building, from the earliest stages of design through construction and operation and this building represents what is possible despite time and budgetary constraints. Sustainable buildings are the way of the future – delivering attractive, healthy, fitfor-purpose environments that add real value through enhanced user comfort and well-being, reduced demand on energy and natural resources, improved performance and above all, higher market values.

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THE NEW HEAD OFFICE FOR THE DEPARTMENT OF ENVIRONMENTAL AFFAIRS (DEA) Case Study

By Boogertman + Partners Architects


CASE STUDY: DEA HEAD OFFICE

15

T

he new 6-star GBCSA Office V1 designrated departmental headquarters building for the Department of Environmental Affairs is located in the City of Tshwane in Arcadia Ext. 6. The site is bound to the east by Steve Biko Street, to the north by Soutpansberg Road and to the west by Oumashoop Street. The latter will eventually make way for the planned extension of Nelson Mandela Drive. The building comprises 27,422 square meters of office and circulation space, accommodates 1305 people and provide parking space for approximately 600 vehicles. The building is procured as a Public Private Partnership project – essentially leased for a 25-year period by the Government from Imvelo Concession Company Proprietary Limited (RF) (the Private Party) who designed, constructed, financed and will operate and maintain the building during that time. The project is a good example of how Government can lead by example through forefront sustainable innovation. In the design of the building, the key considerations were to respond to the spatial and organisational brief of the Client, to provide an environmentally sensitive and sustainable architecture, and to design a functional yet memorable and beautiful building to inspire generations to come.

Location & Urban Context Macro The site is located in the City of Tshwane, capital city of South Africa, in Arcadia extension 6, in the medium density hinterland surrounding the city centre. The property, owned by the City Council, was originally built up however the buildings were demolished at some point in the past and the site had become overgrown and derelict.

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Micro The main access to the site is from Steve Biko Street to the east, however a secondary and ministerial access route also exists from Oumashoop Street to the west. There is a fall in natural ground level of approximately 3 metres from south to north. Surrounding buildings are predominantly 3-4 storeys in height and the rights for this particular site allow a building of maximum 4 storeys in height. Building forms/Urban Fabric The building footprint was strongly influenced by the urban fabric and spatial organisation of the context. The proposed building enhances and preserves the linear, north facing character of the surrounding building forms, and respects the height restrictions by having mostly 3 storeys. The central ‘nautilus’ shaped reception wing of the building deliberately breaks this rhythm to emphasize the importance of the entrance and signify the approach in a subconscious architectural language. Topography In order to respond to the one storey fall across the site, the approach of a semirecessed car parking basement ‘podium’ was adopted. This allows the minimum number of visible vehicles above ground and to create a park-like campus setting with external entertainment and circulation spaces that are pedestrian safe. The exposed western face of the basement provides opportunity for natural ventilation. Design Development A number of previous building forms were considered to arrive at the current building form. The linear approach for the ‘wing’ buildings are functionally derived, however the golden section spiral shape of the reception building is derived from natural


15

references, a more democratic approach (as opposed to dominating and intimidating) and strong symbolic references to origin or birth, growth and aspiration. This then provides for and evocative exploration route into the heart of the building.

Design Brief

The site location is regarded as a gateway to the Tshwane inner city therefore the Private Party was expected to design a facility with suitable prominence that reflects its importance even to international visitors. The new office should communicate an architectural language that reflects the Departmentâ&#x20AC;&#x2122;s environmental and sustainable ideologies. The building should, through its architecture, express to the public as well as the building users the core values of DEA and its willingness to live up to its environmental values through clearly demonstrating aspects of sustainable design, energy and resource efficiency. Finally, it was expected that the Private Party must provide an environmentally friendly building with sufficient energy efficient equipment, energy saving devices and water saving devices with adequate energy efficient cooling throughout the year.

Architectural Design Response Form and layout Due to the size of the building site it was possible to distribute the floorspace relatively evenly to create a general height of only three storeys, which is comfortably accessed by stair. Each office wing includes a central atrium with internal planting at ground level and clerestory windows above the roof to enhance natural light into the building. This also encourages natural

CASE STUDY: DEA HEAD OFFICE

ventilation using the stack effect and night flush ventilation. Building Elements The building is conceived as three distinct elements, consisting of the masculine or utilitarian machinelike office wings, the feminine and organic central reception building, and finally the â&#x20AC;&#x2DC;bridge structureâ&#x20AC;&#x2122; thread that link all of the elements together. Male The main office wings take their inspiration from industrial and machine design. Each of the 3 wings (and 2 short wings to the north) are identical in every aspect. The structure is expressed externally in the form of a concrete frame that provides shading, and also represents the structural grid. Whilst the elevations are heavily indented, particularly on the northern side for sun shading purposes, the roof for each wing is rigorously rectangular and detailing simplistic but elegant. External fire escape stairs at the end of each block provide interest and variation to enhance the rhythm created by the blocks. Decorative screens which are also functional solar shading devices, provide a finer texture and layered effect, and are derived from the veined patterns found on dragonfly wings, giving a light and familiar appearance. These screens were made of double glazed units with patterns printed on the inner faces of the glass, giving opportunity to introduce both colour and pattern. Ever changing shadows created by the screens create a dappled forest-like effect within the offices. Female In contrast with the office wings, the central arrival space and ministerial wing is organic in shape, whilst retailing the common thread of materials and vertical rhythm. The nautilus shell shape, inspired by nature,

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CASE STUDY: DEA HEAD OFFICE

15

retains the powerful archetype of the Fibonacci number sequence and golden section. The asymmetry of the shape creates a dynamic form enhancing the concept of movement or progression. By incrementally increasing the height of the front part of the nautilus, references are created to an organically growing being. This effectively reduces the scale of the entrance to that of a human being and becomes more democratic rather than intimidating in the way of many public buildings. It speaks of inclusion and the entrance procession is inviting and comforting. The element of suspense is created by screening the double height entrance space, only to be revealed at the last minute. The intimacy of this discovery continues into the womblike reception area which houses a ‘discovery centre’ that is freely accessible to the public. Bridge The common thread tying together the discrepant male and female elements is the central circulation corridor which also houses meeting rooms and break-out areas. The design aim was to make this a distinct building element in its own right and to create consistency in appearance to make it recognisable. This is done by confining the shape and width of the bridge by strong parallel lines and by utilizing cladding with a strong horizontal emphasis. By having dropped the height of the front part of the nautilus by a storey, this bridge can now be seen spanning the two separate departments. It also defines the shape of the ministerial suites at third floor level. Feature water collectors at roof level that penetrate the lower level corridors become visual punctuation marks and effectively help to foreshorten the central spine. An enhanced perception of depth is further created by suspending floating bulkhead ceilings in staccato intervals at each block,

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with the remaining areas left ceiling less and therefore higher in appearance. Snaking services are left exposed, providing glimpses into the inner workings of the ‘machine’.

Interior Design Response

A challenge here was to reflect the Africanness of the building without resorting to the usual highly literal pastiche. In our view South African architecture should be equal to the best internationally and that brings with a level of sophistication extending from conceptual design through to details. Our reference to Africa here is at the most basic level where we are crucially located at the ‘origin of the species’, the cradle of humankind. The primeval nautilus shell shape, based on naturally occurring fractal geometry, speaks of birth and origin, growth and progression. The origin point of the golden section spiral is at the reception and from this radiates form-giving lines that affect floor, ceiling and wall layouts. This almost primordial African reference allows a certain freedom to create bright, modern interiors, workstations and shop fitting items which are functional and long-lasting. Colour plays an important role internally, with each functional space provided with a different colour, for instance conferencing and meeting rooms being blue. This assists subtly in way finding, along with a playful signage strategy which is both visual and tactile. In the offices, each block has a different colour scheme reflecting the 6 biomes of South Africa, for instance ‘savanna’ or ‘ocean’. This is demonstrated through the upholstery on the furniture and in accent carpet tiles.

Environmental Approach

The brief called for a minimum 4 Star Green Star rating, along with a maximum energy consumption rating of 115 kWh/sq m/


15

CASE STUDY: DEA HEAD OFFICE

annum, roughly a third of a typical building of this nature. In order not to exceed these targets, stringent energy modelling was iteratively done throughout the design stage, and each possible Green Star point was targeted. This ultimately resulted in 82 points, giving a 6 start office v1 design rating, with the as-built rating currently being pursued. This is only the 3rd six star building in South Africa and by far the largest, and the first Government building with this rating. It was also awarded with the GBCSA highest rated building in 2013/14. The following are some of the green building strategies employed on the project: Building Orientation Office wings are placed on an east/west axis with solid east and west walls, shaded northern facades and less shaded but glassy south facades. Comprehensive energy modeling was used to inform the best combination of external shading versus daylight requirements, glass specification and glare control. Resources Over 1000 cubic meters of rainwater and grey water is collected in basement storage tanks and used for WC flushing and irrigation. Water saving sanitary appliances are used throughout, roving a 30% saving in potable water consumption. Recycling and compacting of office waste reduces the production of comprehensive land fill waste. During construction, a 70% reduction in landfill waste was achieved, along with 95% of all steel being from recycled sources and a 52.2% reduction in cement usage. Natural Light Lightly tinted double glazed units with high luminous efficacy ensure good daylight penetration without the heat energy. Electric lighting energy load is drastically reduced by

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CASE STUDY: DEA HEAD OFFICE

15

BMS controlled light fitting which only come on when required. Overall a 62% reduction in lighting energy is achieved. Ventilation Air conditioning is provided via roof mounted evaporative cooling plant, making it possible to open windows while the air condition is on, under the right circumstances. Passive ventilation is utilized through exposed concrete soffits which absorb daytime heat energy, which is then automatically flushed at night. This results in a temperature reduction of up to 7 degrees from late afternoon to the next morning, reducing in turn the start-up load on the air conditioning system. Solar Energy A 2,200 sq m roof mounted photo voltaic farm will provide for in excess of 20% of the annual energy load of the building, creating approximately 760 000 kwh/annum. Solar hot water heating is also employed. Material Selection The building envelope is highly insulated and incorporated off-shutter concrete walls/columns, insulated terracotta clad rainscreens and some masonry walls. This provides for a combination of thermal mass and insulated walls, including the insulating double glazing with a u-value of 2.1. The roof is insulated on top and the high-tech waterproofing membrane is solar reflective. Off-shutter concrete with a high fly-ash content is used extensively for its raw aesthetic and zero maintenance qualities, however the panel sizes, joints and tie holes are carefully engineered to create a consistent aesthetic.

BIM

The design team, led by the coordinating architects, have produced comprehensive

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3 dimensional CAD models of the building. This not only ensured early clash detection but could also serve as a useful facilities management tool during the operational phase.

Social Impact Community enhancement 23 local community members received and completed adult basic education and training providing general conceptual foundation towards lifelong learning and development, comprising of knowledge, skills and attitudes required for social, economic and political participation and transformation. Empowerment/job creation/ financial viability The project had about 962 employees, of those 462 were sourced from Pretoria


15

and surroundings. Skills development was provided for Engineering, Reinforcement, Shutterhand GR III, Concretehand GR III, Bricklaying, Plastering and Painting to about 29 interns. Cost effectiveness Training programmes were facilitated for onsite by permanent staff members. Innovation The project facilitated the training process similar to the Expanded Public Works Programme successfully used on previous projects in the City of Tshwane where unemployed people from local communities were first trained at training facilities where after the undergo on the job training on site in various trades. This was done under guidance of permanent staff members on a rotational basis. Sustainability Through the 27 year project life, the Private Party has committed to supporting the development of SMMEs and EME’s in the City of Tshwane and to facilitate job creation and poverty alleviation. The Private Party has committed approximately R15m over the full concession period to facilitate access to unemployed youth to participate in the National Youth Development Programme. In this initiative the Private Party will make a contribution to the alleviation of poverty in the City of Tshwane as the students that complete the programmes will have skills to enable them to find suitable employment.

Summary

The architectural design represents a coherent response to a host of complicated requirements by the Client team, including spatial, cost, environmental, operational and security considerations. The architectural team believe that we have not only

CASE STUDY: DEA HEAD OFFICE

met but exceeded the requirement and simultaneously created a beautiful building which will inspire all who work and visit there. The real value of this building lies in the fact that this is the first rated/measurable manifestation of sustainability policies within Government that have been years in the making. By achieving the 6 star accolade, the Department of Environmental Affairs firmly sets the bar for other Government departments and also challenges the private sector to follow their lead. It also serves as a positive example to other African states where sustainability policies are only starting to emerge and regulatory bodies are non-existent. Not only is the impact of this building measurable in terms of its reduction in energy use, water use and waste generation, but the socio economic implications through work creation, local labour force and education has also been described above.

Credits Client: Imvelo Concessions Company Contractor: Aveng Grinaker LTA/Keren Kula JV Space Planning: BEADS Quantity surveyor: Pentad Consulting engineers: PD Naidoo and Associates (Mott Macdonald) Facilities manager: Imvelo Facilities Management Green Star SA-accredited professional: PD Naidoo and Associates (Mott Macdonald) Architect & Interiors: Boogertman + Partners Architectural Key Team: Andre Wright – Director Lood Welgemoed – Lead Project Architect Leone Hessel - Senior Architectural Technician Anushka de Bruyn - Senior Architectural Technician Carin Wolfaard- Lead Interior Architect Johan Pieterse - Graphic Designer

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African Utility Week

INDEX OF ADVERTISERS PAGE 228

African Water Controls CC

94

Alugro (Pty) Limited

32

Andre Du Toit Projects

66

Antalis South Africa (pty) ltd

30

Aquapol Aquatrip cc ArcelorMittal South Africa (Pty) Ltd Asphalt Impressions Avna Architects and Green Building Consultants BASF Holdings South Africa (Pty) Ltd Belgotex Floorcoverings Pty Ltd Bild Architects (Pty) Ltd BlueScope Steel Southern Africa (Pty) Ltd

96; 156-157 86-87 122-123 60 132; 154-155 249 124-125 168; 170-171 40-43

Bulkmatech Engineering (Pty) Ltd

62

CDS Supplies

72

Cape Contours Landscapes Chiefton Facilities Managment Claybrick Association

52-53 150 14

Corobrik (Pty) Ltd

184-187

Decorex

222-223 8

DPI Plastics Drainage Insulation and Protective Systems (Pty) Ltd

16

Evapco South Africa (pty) ltd

20

Fabtec Skylite Geberit Southern Africa pty ltd Green Energy Solutions

256 2-3; 180 257

Hellerman Tyton

102-103

Holm Jordaan Architects & Urban Designers

109-111

Home Technologies

258-259

ICI Dulux (Pty) Ltd

218; OBC

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INDEX OF ADVERTISERS COMPANY Knauf AMF South Africa

Kyasol Green Technologies Pty Ltd

PAGE 192 48

Mapei South Africa Pty Ltd

182

Marcoatings International CC

210

Marley Pipe Systems (Pty) Ltd

250-251

Mellet & Human Architects Merensky Misplon Green Building Consulting pty ltd My Sketch Architecture Nima Solar Solutions Omnicon Media Group PVC Ceilings Pescatech Cleaning Solutions Precast Cement Products

202; 204-205 76 232-233; 242 68 260; IBC 88-89; 134 164 22; 200 36

Pro- Digious Property Development

212

Rajan Haranarian Construction (pty) Ltd

166

Reynaers Aluminium South Africa Pty Ltd Riaan Steyn Architects Pty Ltd Safintra South Africa Pty Ltd Saint-Gobain Construction Products SA PTY LTD/Isover Shaluza Projects cc Shutters Cape Sika South Africa (Pty) Ltd Sustainability Week Technopol (SA) Pty Ltd

252-253 234-235; 241 IFC; 1 10 138; 140-141 6-7 80; 254-255 178 4-5; 34

The Concrete Company

220

Travietta

246

Umbala Paints

196

University of Johannesburg Water Conservation Systems Xnovest Africa

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100-101 230 24


PROFILE

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– WE CREATE CHEMISTRY AND SUSTAINABLE SOLUTIONS At BASF we create chemistry. Our Construction Chemicals division offers advanced chemicals solutions for new construction, maintenance, repair and renovation of structures. Driving sustainable solutions is one of BASF’s core strategic principles. This leads to the development of durable products that improve energy efficiency as well as the speed and ease of construction while meeting green building standards and sophisticated design requirements. With a strong global approach towards product solution offerings, BASF has tailormade products that solve specific local needs and challenges. Weather conditions are a key factor we need to consider when developing a customized portfolio. We believe that structures must be built to last. Our products help expand life cycles and

reduce the projects’ resource consumption. Our Master Builders Solutions portfolio – the BASF brand for the construction industry - includes cement additives and concrete admixtures that strengthen all types of concrete structures and reduce the required amount of water, often allowing the replacement of up to 50 percent of the cement clinker with other materials. BASF’s highly flow-able concrete ensures a faster placement process and provides greater concrete durability. Our waterproofing solutions and sealants help prevent moisture damage, sealing even the most complex of construction geometry. Flooring solutions enable hard wearing floors and meet high hygienic requirements. Should damage occur, our repair systems help restore and improve durability. Our products also support energy efficiency and mitigate carbon emissions. BASF’s portfolio also allows faster construction and improves indoor air quality for better health and comfort. As an example, our Exterior Insulation and Finishing Systems (EIFS) increase cooling efficiency, reducing the use of fossil fuels and facilitating design flexibility*. BASF’s concrete admixtures help minimize the heat application in the production of precast concrete elements and provide self-compacting properties to eliminate the need for vibrating concrete. Admixtures and cement additives support the use of cement types that generate smaller carbon footprint. Our Green Sense Concrete is an example. It is an environmentally-friendly, cost-effective concrete mix optimization service in which supplementary cementitious materials and non-cementitious fillers are used with BASF chemical admixtures to meet or exceed performance targets. Evidence for the improvement of sustainable criteria is provided by third party approved eco-efficiency analysis.


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ES 50 Simply smart

Eco System® 50 is a well-insulated system for windows and doors, that combines aesthetic design and energy efficiency with a moderate price. The system’s HI+ variant achieves Uf values down to 1.6 W/m²K. The Uf of a frame/vent section with 86 mm visible width is 2.3 W/m²K. The system’s limited built-in depth allows its application in many constructions, even with reduced wall thicknesses. Design wise, ES 50 offers, next to the functional design frames, special block profiles resembling wooden frames. The use of invisible fittings results in an even more elegant look, since hinges are no longer in sight. In addition, ES 50 can comply with burglar resistance class 2, offering a safe and secure solution both for residential constructions and utility buildings.


ES 50

TECHNICAL CHARACTERISTICS Min. visible width inward opening window

Min. visible width outward opening window

Min. visible width inward opening flush door Min. visible width outward opening flush door

Frame

48 mm

Vent

30 mm

Frame

21 mm

Vent

87 mm

Frame

67 mm

Vent

74 mm

Frame

42 mm

Vent

99 mm

Frame

50 mm

Min. visible width T-profile

70 mm

Overall system depth window

Overall system depth flush door

Vent

59 mm

Frame

50 mm

Vent

50 mm

Rebate height

22 mm

Glass thickness

up to 32 mm

Glazing method

dry glazing with EPDM or neutral silicones omega-shaped fibreglass reinforced polyamide strips (frame 26.3 mm – vent 22 mm)

Thermal insulation High Insulation Plus variant (HI+)

Available

PERFORMANCES ENERGY Thermal Insulation (1) EN 10077-2

Uf-value down to 1.6 W/m²K depending on the frame/vent combination and the glass thickness

COMFORT Acoustic performance (2) EN ISO 140-3; EN ISO 717-1

Rw (C; Ctr) = 35 (-1; -4) dB / 39 (-1; -3) dB, depending on glazing type

Air tightness, max. test pressure (3) EN 1026; EN 12207 Water tightness EN 1027; EN 12208 (4)

Wind load resistance, max. test pressure (5) EN 12211; EN 12210 Wind load resistance to frame deflection (5) EN 12211; EN 12210

1

2

(150 Pa)

1A

2A

(0 Pa)

3

(300 Pa)

3A

4

(600 Pa)

4A

5A

6A

7A

(600 Pa)

8A

9A

E

(50 Pa) (100 Pa) (150 Pa) (200 Pa) (250 Pa) (300 Pa) (450 Pa) (600 Pa) (750 Pa)

2

1

(400 Pa)

(800 Pa)

A

(≤ 1/150)

3

4

(1200 Pa)

(1600 Pa)

B

(≤ 1/200)

5

Exxx

(2000 Pa)

(> 2000 Pa)

C

(≤ 1/300)

SAFETY Burglar resistance (6) ENV 1627 – ENV 1630

WK 1

WK 2

(windows & doors)

WK 3

This table shows possible classes and values of performances. The values indicated in red are the ones relevant to this system. (1) (2) (3) (4) (5) (6)

The Uf-value measures the heat flow. The lower the Uf-value, the better the thermal insulation of the frame. The sound reduction index (Rw) measures the capacity of the sound reduction performance of the frame. The air tightness test measures the volume of air that would pass through a closed window at a certain air pressure. The water tightness testing involves applying a uniform water spray at increasing air pressure until water penetrates the window. The wind load resistance is a measure of the profile’s structural strength and is tested by applying increasing levels of air pressure to simulate the wind force. There are up to five levels of wind resistance (1 to 5) and three deflection classes (A,B,C). The higher the number, the better the performance. The burglar resistance is tested by static and dynamic loads, as well as by simulated attempts to break in using specified tools.

Level 4 BEE Compliant

Tel. 011 570 1836 • Fax. 011 570 1836

Reynaers Aluminium (Pty) Ltd • www.reynaers.com •Marthinus.coetzee@reynaers.com 07/2013 – 0H0.09C2.00 – Publisher Responsible at Law: E. Fonteyne, Oude Liersebaan 266, B-2570 Duffel


PROFILE

SIKA SOUTH AFRICA (PTY) LTD SIKA SOUTH AFRICA Sika regards itself as a “multi-domestic” company, putting the needs of its local customers at the very centre of its business activities. The company’s products and systems, backed by comprehensive service packages, are carefully tailored to local market needs. On a local level, Sika always puts this sound business principal into practice. Sika strives to provide value-added products and full solutions. Sika’s products and systems are used in almost every aspect of modern living, from building bridges, dams, roads and harbours to high-rise buildings. Sika’s technology is also used for building cars, trucks, buses, boats and industrial products. When using Sika systems, quality, durability and sustainability are added to concrete. Sika South Africa started trading in 1988.

Sika also prides itself on substantial contribution to sustainable development

Our Promise Sika strives for global and local leadership in clearly defined target markets; Concrete, Waterproofing, Flooring, Roofing, Repair and Protection, Sealing and Bonding, as well as Industry. Sika’s innovative solution boosts efficiency, durability and aesthetic appeal of buildings, infrastructure facilities, installations and vehicles throughout production and use.

BUILDING TRUST

Our Values Each product and service reflects our commitment to the three core values that define our Company coined by Romauld Burkard who represented the third generation of Sika’s founder family, Winkler: Courage for innovation, strength to persist, and pleasure or working together Our Voice We speak from experience and with a global understanding. We talk knowledgeably about the local and geographical issues faced by our customers. We respond to our customers quickly,

Sika AG Corporate Profile Sika AG, located in Baar, Switzerland, is a globally active specialty chemicals company. Sika supplies the building and construction industry as well as manufacturing industries (automotive, bus, truck, rail, solar and wind power plants, facades). Sika is a leader in processing materials used in sealing, bonding, damping, reinforcing


PROFILE and protecting load-bearing structures. Sika’s product lines feature high-quality concrete admixtures, specialty mortars, sealants and adhesives, damping and reinforcing materials, structural strengthening systems, industrial flooring as well as roofing and waterproofing systems. Worldwide local presence in 80 countries and some 15 200 employees link customers directly to Sika and guarantee the success of all partners. Sika generated annual sales of CHF 4 829 million in 2012.

SIKA South Africa (Pty) ltd 9 Hocking Place, Westmead, P.O.Box ∙ 15408 Westmead ∙ Durban 3608 Phone: +27 31 792 6500 ∙ Fax: +27 31 700 9593 ∙ www.sika.co.za


Green Energy S O L U T I O N S

PV Solar Systems

Contact

- Design, sales, installations, and finance. - Commercial and Domestic. - Grid-tied, off-grid and backup solutions.

- 082 554 0050 - 011 768 3415 - 61 Naboom Street, Rodepoort, Johannesburg - info@GreenEnegySolutions.co.za - www.GreenEnergySolutions.co.za - www.facebook.com/greenEnergySolutions2012


POWER SOLUTIONS Portable Electricity Backup System | Power Trolley The 1000w modified sine wave Power Trolley can easily supply emergency power TVs, DSTV decoders, M-Net decoders, lights, alarm systems, laptop computers, desktop computers, deskjet printers, radios, hi-fi systems, security systems, cash registers, PABX systems, modems, hubs, routers, etc. The unit can be operated in any position as it has fully sealed internal batteries.

& NOW ONLY R9,999.00 (excl. VAT)

Back Up Electricity – HomeTech Luminous PowerCube The Luminous 1000w pure sine wave inverter, with built in AC multi stage intelligent charger and solar ready input. (Photovoltaic panels can be connected to this inverter). The HomeTech PowerCube 1000 has a 1000W pure sine wave inverter with static contactor for simple power transition. The unit has 2 x 60Amp hour batteries inside the powder-coated box case. This mobile unit can cater for 300W of power during a load-shedding period for 4 hours or 500W for 2.5 hours.

& NOW ONLY R8,999.00 (excl. VAT)

Integrated Off Grid Inverter Back Up Electricity Solution 1500w Pure Sine wave inverter connected directly into your DB Board with Battery Back up. We supply and install a 1500w (1875VA) DevelPower pure sine wave off grid ups/inverter with 4 x 105 amp hour batteries which connected onto your essential appliance circuits in your home DB Board. The system is integrated into your DB Board electrical system. Cross over during load shedding is automatic and seamless >10ms. You won’t even know that there is load shedding happening! Keep your fridge, TV’s, decoders, internet and lights running….

& NOW ONLY R24,995.00 (excl. VAT)

* Prices are subject to change without notice. T & C's apply.

NATIONAL SALES HOTLINE: 076 969 3807 SHARECALL: (0860) 448367 or 0860 HITEMP

www.powertrolley.co.za


Contact Ralph on 076 755 1584


The biggest consumer of electricity in the household is a hot water geyser that will typically consume 15-20 kWh per day per geyser. The next biggest consumer is your pool pump, which would consume 8-14 kWh per day depending on the timer settings. A Solar Powered Swimming Pool pump is powered solely by two to three solar modules connected directly to a solar powered pump using no mains power whatsoever â&#x20AC;&#x201C; a saving of 8-14 kWh per day every day. A typical residential installation including solar modules and pump will cost approximately R 14 000 incl VAT. This equates to a payback period of less than 18 months at current electricity tariffs. The cost compares favourably with a solar water heater or heat pump but offers better value, as this product will run for many years without any electricity cost.


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2014/12/02 2:30 PM

Green Building Handbook V8  
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