Building Engineer June 2020

the journal of the chartered association of building engineers

June 2020

buildingengineer June 2020 | www.cbuilde.com

To the Lighthouse

Blue sky thinking

Pooled knowledge

Heating trials

Building sustainably with timber raises as many questions as it answers

From theory to practice, why blue-green roof systems need to become the norm

The global collaboration that assesses new watermanagement innovations

Can domestic consumers switch to thinking of heat as simply another utility?

Open and shut case The ventilation, acoustic and thermal comfort problems of our own making

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CABE has partnered with Fire Risk Consultancy Limited to provide a range of online fire safety training courses at discounted rates for members.

Designed and run by FRC, each CPD course focuses on an aspect of Fire Safety and delivers valuable insights to learners.

Available Courses: • • • • • • • • • •

External Fire Spread B5 Access and Facilities Human Behaviour in Fire Fire Safety in Specialised Housing BS 9999: The Concept Fire Safety in Heritage Premises Responsible Persons Responsibilities Fire Doors - What you need to know Fire Warden Training Loft Conversions.

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Book now at: cbuilde.com/onlinetraining 12/05/2020 09:30

JUNE 2020

CONTENTS

building engineer WELCOME 04 Congratulations!

New CABE President Jayne Hall takes a positive view of the future

25 Lighting by numbers Facts and figures you need to know about LEDs

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26 SuDS standards If you’re not taking SuDS seriously it’s time to start

INFORMATION

28 Living history Sustainable conservation at a new heritage centre

07 New Building Engineer website

INTELLIGENCE

JUNE 2020

30 Blue sky thinking Boosting biodiversity with a blue-green roof

08 The briefing News and views

32 Set for change Making cement more eco-friendly with GGBS

12 Good with wood?

Why we need to relinquish our reliance on concrete

34 Heating trials Will consumers buy into the notion of heat as a utility?

35 Science of the future Open up possibilities with state-of-the-art ventilation

17 2020 vision Thermal imaging explained

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14 To the lighthouse Over to Finland where a residential unit reaches new heights of sustainability

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INSIGHT 18 Through the roof Understanding the importance of U-values

36 Hand in hand Construction’s reciprocal relationship with academia

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20 Better living through chemistry Installing a roof system that neutralises CO2 21 Kerb your enthusiasm SuDS solve a university’s flood-risk challenge

COMMUNITY

22 Pooled knowledge The water technologies supporting urban resilience

Building Engineer is published on behalf of the Chartered Association of Building Engineers (CABE)

by Redactive Publishing Ltd Tel: 020 7880 6200 Email: info@redactive.co.uk redactive.co.uk

Printed by Warners

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40 Open and shut case Setting the standards for acoustics, ventilation and overheating in a new guide

Publisher: Will Hurrell Editor: Rebecca Davies-Nash Email: cabe-editorial@redactive.co.uk Designer: Joe McAllister Picture researcher: Claire Echavarry Sub-editor: Alison Krog Production: Aysha Miah-Edwards Email: aysha.miah@redactive.co.uk Tel: 020 7880 6241 Advertising: Email: cabe-ads@redactive.co.uk Tel: 020 7880 6206

48 Movers and shakers

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49 Profile

Volume 95 No 6 June 2020 The Official Journal of the Chartered Association of Building Engineers Chief Executive: Dr Gavin Dunn Patron: The Earl of Lytton President: Jayne Hall Email: info@cbuilde.com cbuilde.com

Subscription Rates: UK and Ireland £85.00, Overseas £120 (per annum, 10 issues a year, sterling). Digital subscription to buildingengineer.org.uk £50 + VAT per annum.

Building Engineer has been carefully prepared but articles are published without responsibility on the part of the publishers or authors for loss occasioned to any person acting or refraining from action as a result of any view, information or advice included therein. Articles published in Building Engineer do not necessarily reflect the opinions of the Chartered Association of Building Engineers, nor can the Chartered Association of Building Engineers, the publishers or authors accept any responsibility for any claims made by advertisers. ISSN: 0969-8213

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JUNE 2020

WELCOME

Congratulations!

The unusual inauguration of CABE President Jayne Hall

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ay is usually an exciting month in CABE’s calendar, with the inauguration of a new President for the Association. We usually find some way to celebrate the occasion with colleagues, professionals and friends. But this year it has been very different.

Due to Covid-19 all celebrations had to be cancelled and Ant Burd and Jayne Hall met up at HQ late in May for Ant to hand over the reins from a socially acceptable distance to our new President Jayne Hall.

Ant Burd Immediate Past President and Jayne Hall President might not be able to deliver their speeches as intended, but now take the opportunity to reflect on experiences and challenges as they start their new positions on the CABE Board.

Experience and reflection After my piece in last month’s journal you probably thought that might be the last you would hear from me. I’m afraid not quite yet.

As I step down as President, I have to say thank you and goodbye to our Past President, David ‘Two Terms’ Taylor, Richard Smith and Darren Burrell all of whom leave the board. Our quarterly board meetings take place at the weekends (and with Covid-19 virtually, too) and several of its members continue to support CABE activity within their respective regions. This is a huge undertaking, and we continue to be truly grateful for all that they, and everyone at the regions, do for the Association.

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Now, you might think I’m going to reel off all off all the things that I’ve achieved while President at CABE, but it doesn’t work like that. We’re a team, and we have a clear and established five-year strategy of all that we want to achieve. A year is a very short period.

But in that time, working with and supported by our amazing HQ team, we have continued to progress, all the while helping to set the agenda and leading by example. Including such highlights as: Publication of our Code of Professional Conduct supported by guidance on Ethical Professionalism coupled with our revised Competency Framework Continued top-table involvement in all aspects of the Grenfell response and Hackitt review; including development activity around professional competency across the industry and providing input into MHCLG’s revisions of both the technical and procedural aspects of the English Building Regulations The CABE rebrand (including our new journal, website and digital members’ platform) The establishment of CABE’s sustainability strategy, including the CABE HQ refurbishment – designed to nearly zero energy The establishment of our new regional office in Hong Kong; and last, but not least Securing full membership of the Engineering Council.

I’ve had the privilege of being on the CABE Board for almost three years now, where much of the above and more has been developed and decided upon. I served two years as a Vice President, one as President and now one last year as Immediate Past President.

IMAGES: PAUL MOCKFORD

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NEW PRESIDENT JAYNE HALL

Challenges for the future New President, and Chair of the CABE Board, Jayne Hall Welcome to my inaugural letter as President of CABE. When I first encountered Ant Burd 13 years ago, he was delivering a stimulating piece on the changes to the Building Regulations, hot off the press from the Deputy Prime Minister’s office. I was impressed by how easily he managed to turn a very dry subject into an entertaining lecture. Little did I know that he would become a valued mentor and friend. I cannot say how privileged I feel to follow in such revered footsteps.

I hope I will do justice to the role that other highly respected members have held before me.

I am generally a glass-half-full kind of person, but the challenges thrown to our industry over the past few years have been trumped by the extraordinary global chaos that has followed the unforeseen appearance of a microscopic entity in our midst.

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In that time I’ve made some great new friends and forged ever deeper relationships with some old ones.

The debate is always healthy, the challenge always professional and the support unstinting.

I will look back with considerable pride at all that we’ve achieved this past year. Now it is the time to hand over to our new President Jayne Hall. Jayne has been a friend of the Association for a very long time. What can I tell you about the covent-schooled lady from Burnham on Sea? She was never going to be held back from doing what she wanted to do, that’s for sure.

She entered our industry with a focus on architecture and had a design consultancy that specialised in signage and wayfinding. Then finding herself a single mum, she entered a profession close to my heart, building control, as an assistant trainee.

Jayne undertook a part-time degree in Building Control Studies. She was joined on that course by Diane Marshall PPBEng, so clearly a course that was a hot bed for future Presidents of the Association.

From there Jayne became a Chartered Member of CABE and a committee member for the South West Region. She quickly became Head of Building Control for her authority, and – following a dabble with national activity – she soon became a Vice President and then President of LABC. She now finds herself heading up the Building Control and Planning Enforcement team for South Gloucestershire Council as Built Environment Enforcement Manager.

Jayne is a doer, a get up and goer; and she has a passion for all things built-environment related. She’s hardy, she’s resilient and she seeks collaboration in all that she does. She’s also our Diversity Champion. I’m so proud to hand over to her.

It’s been an honour as CABE continues its journey, onwards and upwards. Take care, stay safe.

Ant Burd PPCABE FCABE, now CABE Immediate Past Present

Welcome to the board Joseph Birt VPCABE FCABE – Vice President I am greatly honoured to be elected to the position of Vice President of CABE. My career to date has consisted of 22 years within Local Authority Building Control, the latter 12 years as Specialist Support Officer for a cluster of councils, which included responsibility for advising on fire safety aspects of the Building Regulations. Three years ago I started out in private practice. I now feel like the gamekeeper turned poacher, as I often engage with my former colleagues from the other side of the table on Building Regulatory matters.

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Buildings are becoming more complex with the interrelationship of materials, technologies, systems and services.

To create these amazing structures to exacting modern standards requires an expert multi-disciplinary team. I am, therefore, proud to be a member of CABE, as I believe it is the only association that accurately describes what we are; we are not singularly architects, structural engineers, services engineers or building surveyors, but an incorporated association of architects and surveyors and more – we are chartered building engineers.

It is my aim to ensure that as the Association grows and develops, we stay true to our roots and deliver excellent services to our membership.

Dan Fordham FCABE – board member I am a structural engineer based in Cambridge. I formed my company in 2004, initially

as a sole practitioner, then growing into a small practice. I am currently Vice Chair of the Membership and Professional Standards Committee with CABE and regularly sit on CABE member interview panels. I also sit on the Small Practitioners Panel for IStructE. Since joining CABE I have felt extremely welcomed, as it is clear the Association truly follows its ethos on collaboration.

Other professional bodies focus on their specialisms within our industry and provide essential services needed for their own key areas to thrive. CABE is unique in that the membership covers the whole

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NEW PRESIDENT JAYNE HALL

WELCOME

Many of you will know I have always championed the argument for improved diversity and inclusion, so social isolation has never been part of my vocabulary.

And disappointing though it is to see some of our regional buildeng events being postponed, I applaud the team at HQ for embracing the Fourth Industrial Revolution and rolling out the new CABE Community website and providing regular online CPD webinars to keep members up to date and occupied while we adjusted to government-imposed lockdown. If you haven’t signed up, I urge you to do so (cbuilde.com/webinar).

I am a great believer in reframing the negative to look for the positive, to seek out opportunities in adversity.

Now is the time for us all to reflect on our ethics and social responsibilities and to rethink how we deliver our services. We need to move forward as building engineers with greater confidence in our competencies, to reach out to fellow professionals and embrace constructive collaboration.

The emergence of fully operational Nightingale hospitals in the UK have proved our industry can rally round to mobilise quickly alongside the health service and military and other agencies in a highly successful way to kit out an emergency hospital within a matter of days.

No one really knows what the post-Covid-19 world will bring, but it is fair to say that the load for some of us might tip us to breaking point. There is no magic formula for recovery, and we cannot predict what the new normal might be as the restrictions are gradually lifted. Each of us probably has a story to tell about the impact the past few months have had and some of us will have fared better than others.

I am proud to be a trustee of the CABE Benevolent Fund and pleased that, through establishing a special

emergency fund, we are able to offer support to members who have been hit harder than others by the sheer unexpected and fast-moving implications for people’s health, emotional and economic wellbeing. Thank you to all of our members, past and present, who have made donations to the Benevolent Fund at CABE events, through adding a gift to their annual subscription, leaving a legacy or by responding to the sudden growth of the Coronavirus pandemic.

Over the past year, with CEO Gavin Dunn at the helm, an invigorated board of directors and an enthusiastic and knowledgeable team at HQ, CABE has really shone as a bright light while the construction industry gears up to take on the rising tide of safety reform.

There is a level of CABE membership for everyone, from students to chartered engineers. Our Association is member-focused to guide us through change, to support every one of us, both on our individual career paths and collectively through raising standards and competencies and representing building engineers in the corridors of power to ensure our voice is heard.

If the past weeks have shown us anything, it is how fragile society, the economy and the whole structure of life as we know it is. I would like to thank my fellow members, the Association’s board, regional and regional committees and chapters around the world, and the whole team at HQ for allowing me the opportunity to be part of the global CABE family as we all look forward to a dramatic year of change.

Take care, keep safe and well and – whatever hand you are dealt – know that CABE is here for you, and ‘Always look on the bright side of life’.

JUNE 2020

“I believe in reframing the negative to look for the positive, to seek opportunities in adversity”

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of the built environment and is perfectly placed to bring together otherwise segregated professionals. It is this that makes CABE such an open association.

One of the criticisms to come out of the Hackitt review was that all the professionals within our industry sit in isolated silos. Never truly collaborating.

The industry is going to change, and it is CABE that needs to be the leading body, drawing on the abundance of skills from its membership to allow the industry to integrate, adapt, develop and grow.

I am extremely excited to join the board at this time. However, it is also a very difficult time; the construction industry was already facing a challenging future, and this has been made more intense by the recent global pandemic. This is time for CABE to continue to push for change and to drive the industry forward.

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Jayne Hall PCABE FCABE, CABE President

Russell Urwin FCABE – board member Through my role as Northern Region Chair, I always look forward to interacting with friends and colleagues of the Association at the many excellent events held during the year, and 2020 was set to be no exception.

Thrilled as I already was at taking up another three year term as a NonExecutive Director, this year now looks to be one that will offer a completely different experience, albeit with a more interactive, multi-media approach, but one I’m really excited to be a part of.

As a Principal Consultant of Turner & Townsend, with more than 28 years’ experience within the construction industry – 15 years as a senior leader within the housing sector, delivering a

broad range of technical professional roles across building surveying, asset management, health and safety and risk management. I maintain a passion for improving the outputs of our sector and raising the standards we apply to ourselves as professionals.

Putting aside the absence of this year’s presidential inauguration, and the impact on our regional CPD activity, I look forward to utilising my knowledge and experience supporting our new President Jayne Hall and the executive team over the coming months as the CABE community rally together to meet the challenges, for both the industry and our Association. Working alongside our excellent HQ team as we continue to take CABE forwards in these unprecedented times with a smile on our faces.

What a year this looks to be.

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BUILDINGENGINEER.ORG.UK

INFORMATION

Your favourite construction engineering journal is now only a click away

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or as long as I can remember, whenever I have spoken to CABE members and mentioned that I work on Building Engineer, the first question I get asked is: when is it going to be available online? Since the relaunch of the journal in October, Building Engineer has been available online in a digital format, but now we can finally, and proudly, say that Building Engineer is truly part of CABE’s digital transformation with the launch of buildingengineer.org.uk buildingengineer.org.uk contains all the same in-depth articles and news as the journal as well as some exclusive online content. All CABE members will

be able to access the whole site for free – look out for an e-mail with your log in details, which means you will no longer have to wait for the next edition to pop through your letterbox.

Colleagues and friends of the Association will be able to view sections including news, but if they wish to read any articles, they will need to sign up to a digital subscription of Building Engineer. cbuilde.com/page/building_engineer_subscribe The new site contains links to further reading and the opportunity to sign up for a Building Engineer newsletter to keep you abreast of industry news and legislative changes.

This is a genuinely exciting development, and one that I am sure that all building engineers will be keen to embrace.

Laura Richardson Head of Communications

buildingengineer.org.uk

JUNE 2020

It’s here…

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INFORMATION

The briefing

NEWS AND VIEWS FROM THE INDUSTRY

Green recovery?

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Read Ailean Beaton’s article at bit.ly/AileanBeaton Read the government’s recovery roadmap at bit.ly/RecoveryRoadmapBTW

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Pollen count

GLOBAL CARBON EMISSIONS COULD NOW FALL BY

6%

DUE TO COVID-19 LOCKDOWN MEASURES

Scottish Natural Heritage (SNH) has published new guidance for the planning and construction industry to create a more resilient and nature-rich urban environment. Pollinators including bees, wasps, moths, butterflies and flies are vital for our biodiversity, but face challenges due to changes in land use, habitat loss, diseases, pesticides and climate change. The guide offers advice on how best to fit pollinators into urban design and construction with a series of easy-to-follow steps to suit project budgets and sizes.

Wildflower meadows, flowering trees, hedgerows, nectar-rich plants and herbs, window boxes, green roofs, living walls and sustainable drainage systems can all help expand the habitats of pollinators.

They also support biodiversity, improve wellbeing for inhabitants and reduce costs from urban maintenance such as mowing road verges.

For a copy of the guide, contact SNH at snhmedia@nature.scot

IMAGE: ISTOCK, GETTY IMAGES

JUNE 2020

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s the world reels from Covid-19, there have been plenty of positive stories about the effects on nature. From goats roaming through Llandudno, north Wales (bit.ly/NWgoats) to improved urban air quality, environmentalists have been quick to point out that the break in human activity has shown the possibilities of slowing climate change.

Rising global carbon emissions could now fall by 6% over the next few months, according to the United Nations’ World Meteorological Organisation (WMO).

However, as its Secretary-General Petteri Taalas warned: “Covid-19 may result in a temporary reduction in greenhouse gas emissions, but it is not a substitute for sustained climate action.”

Ailean Beaton’s article in Holyrood discusses how different governments are facing the new challenge of restarting the economy in a way that supports the climate change commitments they made before the pandemic. The UK Committee on Climate Change has already said that its annual progress report to parliament this month will refocus to include discussion of how economic rebuilding efforts can be designed to support environmentally sustainable industries and activities.

Beaton notes, too, that where people have embraced new ways of working and living they may not want to just return to how things were done before. “There is a real opportunity for governments to make sure that the economic stimulus packages, everything that comes in place to reignite the economy, is different and better to what was in place before,” says Charlotte Hartley of the 2050 Climate Group.

A sentiment that is echoed by Dr Richard Dixon, Director of Friends of the Earth Scotland, who notes that for construction the standard response is to: just keep building so the sector can right itself, but that in this case, the sector needs to change what it is building. Experts are unanimously saying that now is the time to invest in low-carbon construction techniques, energy-efficient housing, green/blue systems and biodiverse urban environments; and that this will not only constitute a green recovery for the economy but it will also save the construction industry.

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THE BRIEFING

28 pledge to tackle climate change Free chartered environmental webinars

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Chartered Association of Building Engineers (CABE) is a professional body licensed by the Society for the Environment to award Chartered Environmentalist (CEnv) status. To find out more about becoming a CEnv via CABE, please visit cbuilde.com/register_with_socenv

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On behalf of members and with the advice of the Climate Change Panel, CIC will: 1. Support and provide co-ordination and information exchange for the climate change and biodiversity action plans and activities of individual CIC member organisations.

2. Work with the professional bodies to develop partnerships with governments, the Committee on Climate Change, the Construction Leadership Council and other governmental and nongovernmental organisations in pursuit of these objectives.

3. Communicate activities both internally and externally, including through the publication of a regular Climate Change and Biodiversity Digest.

Stephen Hodder MBE, Chair of the CIC said: “Those in the built environment have an enormous role to play in reducing carbon dioxide emissions from new and existing buildings and infrastructure.

We hope in forming this unprecedented alliance our collective skills, knowledge and influence will drive necessary change.”

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If you are a Chartered Environmentalist via CABE and are interested in presenting as part of a future webinar series, contact Phil at phil.underwood@socenv.org.uk.

appropriate adaptation of the built and natural environment.

JUNE 2020

he Society for the Environment (SocEnv) is committed to facilitating learning and shared good practice across the environmental profession. Its free webinars are just one of the ways to achieve this. They allow registered environmental professional speakers to showcase their expertise and for viewers to engage with a topical issue and ask questions.

In celebration of this year’s World Environment Day theme of biodiversity, throughout the week commencing 1 June SocEnv is running a special series of webinars exploring key aspects of biodiversity including what everyone – from organisations to individuals – can do to boost biodiversity in their area. Culminating in World Environment Day on 5 June, the webinars will feature expert insight and analysis from chartered environmentalists across a variety of sectors and organisations.

Find out more and book your place on one or more of these biodiversity webinars via SocEnv’s dedicated hub: socenv.org.uk/webinars. If you are reading this after the 5 June, you can catch up with all the webinars in the series via the same hub. Here you will also find all SocEnv’s past webinars – including the recently completed Climate Change series.

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ABE and 27 other members of the Construction Industry Council (CIC), together with the UK Green Building Council, the Edge and the University College of Estate Management, have jointly pledged to work together to tackle climate change. They have issued a joint statement that recognises that the breakdown in global climate and biodiversity as a serious issue and that the built environment is a major contributor.

The 28 signatories to the statement acknowledge that the built environment accounts for almost 40% of energy-related carbon dioxide emissions while having a significant impact on natural habitats. To this end, the signatories have established a Climate Change Panel, formed from leaders within each profession and convened by CIC, to aid collaboration and shared endeavour between the professional bodies. The panel will: Drive a net zero carbon emissions pathway Identify and promote examples of best practice carbon reduction, climate resilience, biodiversity protection and improvement Encourage thought leadership and innovation to bring about change Share best practice in terms of education accreditation, membership qualification and CPD development Provide advice on all matters relating to the mitigation of the climate change and biodiversity ‘emergencies’ and the

Download the statement at bit.ly/CCandBEstatement

Low-energy retrofit guide EnerPHit is the gold standard of performance for existing buildings.

James Traynor’s practical guide provides architects and designers the tools to retrofit our existing buildings.

To meet the target of reaching carbon zero by 2050, or much earlier, building owners across the UK will be required to upgrade buildings to adhere to increasingly stringent energy performance requirements.

Nearly 20% of UK carbon emissions

are attributed to the heating and cooling of buildings. By tackling inefficient stock, both carbon emissions and fuel poverty can be addressed, while providing improved thermal comfort and a healthier environment.

The guide offers clear methodology and case studies to improve current buildings for future use.

Available from RIBA bookshops at bit.ly/2lEXvrV

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INFORMATION

#yearofnetzero

JUNE 2020

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ulti-disciplinary engineering consultancy Cundall has named 2020 the Year of Net Zero. It will work alongside the Royal Institution of Chartered Surveyors (RICS), Royal Institute of British Architects (RIBA), the Chartered Institution of Building Services Engineers (CIBSE), the UK Green Building Council, the Greater London Authority (GLA) and the London Energy Transformation Initiative (LETI) to help unify the industry and define targets for achieving net-zero carbon in both new and existing buildings.

They will then lobby to set these targets in legislation, originally planned to showcase at COP26 in Glasgow in November 2020, now postponed until summer 2021.

Simon Wyatt, Sustainability Partner at Cundall, said: “We saw more industry action around sustainability in the second half of 2019 than in the whole preceding decade… Ultimately, achieving net zero is an engineering problem that needs a technical solution, and we are dedicated to helping the industry achieve it.”

Cundall is working with the GLA to launch new standards for wholelife carbon for all referable schemes, simultaneously setting out a proposed roadmap and targets for all developments in the next decade. The next step will be to set intensive targets for whole-life and embodied carbon and mandate compulsory reporting for all building projects.

NICE air quality

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he National Institute for Health and Care Excellence’s (NICE) guidance Indoor air quality at home noted that as we spend 90% of our lives inside, poor air quality within buildings affects our health. The document issues recommendations to stakeholders including local authorities, healthcare professionals and ventilation specialists.

Alan Macklin, Group Technical Director at Elta Group, comments: “There has been significant research into the impact of bad air quality in our buildings, especially as the insulation of structures reduces levels of natural ventilation. Sick building syndrome (SBS) has made

an unwelcome return, and the link between CO2 and concentration levels in schools is alarming.”

Domestic air quality is no better, and given that 60% of time is spent at home (according to the guide) it’s an important focus. “From product design through to installation, the focus must be on adopting a whole-house approach to heating and ventilation, taking energy efficiency into account while striving for optimum air quality,” he says.

For an understanding of the sources and symptoms of poor indoor air quality and what actions to take to improve it, read the guide at nice.org.uk/guidance/ng149

See Cundall’s #yearofnetzero campaign, UN’s #2030isnow and #decadeofaction campaigns

Amy Flemming makes a case in The Guardian for cities to embrace an anthropological approach to planning that works with nature, instead of embracing smart systems.

She sites Julia Watson’s book Lo-Tek: Design by Radical Indigenism as a guide to ancient habitation solutions to modern environments – as sponge cities architect Kongjian Yu comments: “Ancient wisdom tells us how to live with nature in a smart way.” Examples include the Zuni people in New Mexico, who create waffle gardens to capture, store and manipulate water for desert

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crop farming and the Khasi hill tribe in Northern India whose living tree-root bridges can withstand monsoon better than any human-made structure.

Watson notes that nature-based technologies such as these could be explored for urban use – the living-root bridges could be grown to reduce the urban heat island effect by increasing canopy cover for example.

Read the full article at bit.ly/AFlemming To order Julia Watson’s Lo-Tek: Design by Radical Indigenism, visit bit.ly/LoTek

IMAGE: ISTOCK, GETTY IMAGES, SHUTTLESTOCK

Dumb cities

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THE BRIEFING

Living Lab

ADAPT AND REUSE when pressure is reduced. The absence of dissolved oxygen improves the efficiency of heat transfer and retention. By removing the dissolved oxygen from the central heating’s circulation and electronically controlling the now enhanced heat, savings and reductions in CO2 emissions can be made. The Living Lab trials will provide real-world validation to reinforce the results of the testing we did with the Scottish Environmental Technology Network in conjunction with Strathclyde University. The tests showed energy and carbon savings of up to 49.8% for domestic homes and up to 39% for commercial buildings.”

The Living Lab is a unique trial facility of 100 connected homes, where innovative businesses can rapidly design, market-test and launch new energy products and services. See page 34 for details.

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t the NBS Construction Product Leaders’ Summit, Dame Judith Hackitt noted that the construction supply chain must change to take maximum advantage of digital technology and made it clear construction materials manufacturers must improve their standards, processes and digital toolkit.

With this in mind, NBS Source provides a digital platform embedding standardised construction product information, using data from

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thousands of manufacturers, in the places specifiers need, across the project timeline. It is set to help the construction industry make better-informed product decisions and give manufacturers a highly targeted route to market for their products, helping them grow as well as comply.

To help build the golden thread of information for construction materials, visit manufacturers.thenbs.com/ nbs-source

Read at bit.ly/Livingwithbeauty

EMBODIED CARBON TOOL Engineering firm Thornton Tomasetti has released an embodied carbon measurement tool, BEACON, to aid engineers in understanding and modifying carbon optimisation from the beginning of a project. The open source tool (bit.ly/BEACONgitbook), provides users with a visualisation of a project’s embodied carbon quantities, enabling engineers to design structures that are more sustainable and efficient.

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Blueprint for construction products

The greenest building is the one that is already built, is the key message from the government’s Building Better, Building Beautiful Commission report (Jan 2020). The report states: “It is desirable to make better use of existing buildings in city centres given not only the colossal challenges facing traditional urban-based business but critically the need to better use finite natural resources. We want to dispel the perception that renovation represents poor value for money in comparison with demolition and reconstruction.” The report calls for a major shift in policy towards the reuse, refurbishment and retrofit of existing building stock to manage the longterm impact of the built environment.

JUNE 2020

Scottish energy firm Biskit Controls has become the latest business to demonstrate an innovation in the Energy System Catapult’s 100-home Living Lab. Biskit has developed a patented technology called the Hydro Genie, which is designed to improve the performance of central heating systems by removing oxygen bubbles from the circulating water to improve heat transfer from the boiler to the water and from the water to radiators. Fitted alongside an existing boiler or heat pump, it is designed to reduce the amount of gas needed, lower energy bills and carbon emissions, while keeping the home warmer.

Jim Bisset, founder of Biskit Controls, said: “Hydro Genie applies fluid dynamics and Henry’s Law to wet heating systems.

Assuming constant temperature, Henry’s Law predicts that dissolved gasses are released from liquids

SEA CHANGE The Roca London Gallery had, since February, been hosting Sea Change: Flood Resilient Architecture for the 21st Century exhibition. The collection of projects showed how urban planners and residents have been adapting to frequent flooding in cities. While the gallery is currently closed due to Covid-19, the striking images are well worth viewing online at: bit.ly/RLGSeaChange or visit Roca Gallery at bit.ly/Rocavirtual

Have an opinion on something in this issue or something you’d like to discuss with your peers? e-mail the Editor at cabe@redactive.co.uk

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INTELLIGENCE

JUNE 2020

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Sustainability credentials aside, the human cost of the housing crisis cannot be ignored. As the report notes: “The housing crisis in the UK has a fundamental and negative effect on our quality of life. A lack of affordable housing is consistently linked to poverty, poor mental and physical health.” Success in creating a flourishing housing industry, and in turn, a flourishing timber industry, would be felt right across the country.

Offsite timber-frame construction

a significant downturn in production.

Until recently, this stigma has remained.

Perceptions are very different in Scotland where timber frame remains wellrespected, with production hardly affected and timber frame continuing to account for 75% of all new houses.

Quite rightly, we’re now seeing a shift in mentality throughout the rest of the UK. It’s a method that combines speed, quality and efficiency; all of which contribute to affordable, low-carbon, efficient homes. Today’s offsite timber-frame homes – thanks largely to technological advances – are also high quality.

Offsite construction’s controlled approach to planning and constructing buildings significantly minimises any room for error, and gives opportunity for new eco-friendly process planning, designing and installing within a much-reduced time frame and budget. The factory setting allows better quality control of

“CLT is easy to transport and modify, reduces noise pollution on site and is highly cost efficient”

Throughout the 1950s and 1960s the UK building industry moved towards industrialised forms of building, and in the early 80s prefabricated housing became dominated by timber-frame systems.

Timber-framed dwellings grew steadily to around 30% of the new-build market until negative media coverage and the public’s continued general suspicion of modern construction methods contributed to

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he government needs to build 300,000 new homes in England per year while achieving zero carbon emissions by 2050.

Construction 2025, a joint government and industry strategy, has outlined targets for the UK construction sector, including halving constructionrelated emissions and project delivery times, and reducing construction costs by a third, by 2025. These ambitious goals are made no less so by the industry’s reliance on concrete, “the most destructive material on Earth,” according to The Guardian.

According to the All-Party Parliamentary Group (APPG) for the Timber Industries’ report, How the timber industries can help solve the housing crisis, if 270,000 of these new homes were to be built by the timber industry, three million tonnes of carbon dioxide would be absorbed and stored each year and build times would be 30% quicker. The report goes on to argue that using timber in construction is central to meeting emissions targets and urges the government to implement the recommendations of the Climate Change Committee by increasing the use of timber in construction.

Good with wood?

Jeremy English, Director at Södra Wood, believes timber is the answer to the building industry’s problems, if only it can give up concrete…

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STRUCTURAL TIMBER

materials, chain production setups and easier implementation of processes and manufacturing methods. Research published by WRAP also demonstrates that the use of timber-frame construction components can reduce the amount of waste generated on site by up to 40%.

According to the NHBC, timber-frame construction currently accounts for just 15% of UK housing output. The benefits outlined above, coupled with the fact that government housing targets simply cannot be met through traditional methods alone, makes me confident that this figure will increase exponentially in the years to come.

The elephant in the room

For more information, please visit sodra.uk

270,000

of new homes were to be built by the timber industry,

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if

layer preventing an excessive rise in temperature within the unburnt core.

The core continues to function, providing a predictable period of fire resistance.

As Andrew Waugh of Waugh Thisleton Architects, one of the UK’s leading proponents of timber construction, notes: “The reality is that the evidence says we’ve got 12 years left to sort out climate change – we’ve got to start changing the way we do things. And we’ve got to keep pushing the message about the safety of CLT. It’s not only quicker to put up; it’s safer, healthier, lighter and locks away carbon.”

Presently, the Structural Timber Association, among others, is currently augmenting its already extensive fire-resistance testing data. Further investigation will determine how the in-situ fire resistance characteristics of structural timber systems can be best exploited in modern high-performance buildings. Once they arrive, I believe we should then have an informed review of regulations.

JUNE 2020

No current conversation about timber is complete without comment on the government’s catch-all ban on combustible materials. At the end of 2018, as part of fire safety improvement measures intended to prevent another tragic blaze like that seen at Grenfell Tower, the then Housing Secretary, James Brokenshire, introduced new legislation banning combustible materials on new high-rise homes above 18m. The

government is now considering lowering the height threshold for combustible materials to at least 11m according to current Housing Secretary, Robert Jenrick.

Architects, builders and suppliers of timber and engineered timber products are looking at what the future holds for mass timber builds following this catch-all ban and, in particular, the specification and use of cross-laminated timber (CLT) as a strong, lightweight structural component for multi-floor structures.

While there’s no question that these restrictions are intended to enhance occupant safety, we mustn’t lose sight of CLT’s inherent benefits; benefits that have made it an increasingly popular choice for structural components since its introduction into the UK in 2004. It’s easy to transport and modify, it reduces noise pollution on site and it’s highly cost efficient to produce and use.

Available testing evidence indicates that structural timber and CLT products also have predictable charring rates.

When exposed to fire, the load-bearing core of a beam or truss will remain intact while the char layer remains to protect it. The char forms an insulation

3m tonnes of carbon dioxide would be absorbed and stored each year and build times would be

30% quicker

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JUNE 2020

INTELLIGENCE

BUILDING ENGINEER

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To the lighthouse Stora Enso’s LightHouse project in Joensuu shines a light on the use of wood to reduce the construction industry’s CO2 emissions

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f the building sector is to truly change to meet the decarbonisation goals of the Paris Agreement, both operational and embodied emissions need to be addressed. There must be greater scrutiny of how buildings can be made more sustainable in all stages of their lifecycle – including material choice.

This is the message from the World Green Building Council (WGBC), an international organisation dedicated to promoting the practice of sustainable building. Its report Bringing embodied carbon upfront highlights the importance of emissions from materials, and it advocates for new policies – such as the EU’s Level(s) framework – that seek to make a building’s lifecycle assessment mainstream.

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As members of WGBC, Stora Enso is keen to increase the knowledge about sustainable construction and construction materials, and believes that timber offers a solution.

“We need to change the raw materials we are constructing with,” says Jari Suominen, Head of Stora Enso’s wood products division. “Timber has everything. It has a low-carbon footprint due to the relatively low greenhouse gas emissions in production, it stores carbon throughout its lifetime, our sustainably sourced wood is renewable and at the very end of its lifecycle, and wood products can be safely converted into renewable bioenergy without becoming waste,” he says.

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TIMBER CONSTRUCTION

Tall, impressive and sustainable.

The 14-storey high building is made almost entirely from wood

Carbon sequestration

and storage Trees grow by absorbing carbon dioxide from the atmosphere and store it as biogenic carbon. In European forests, the average rate of sequestration and storage is about 750kg of biogenic carbon per single cubic metre of wood. At end-of-life, when ultimately wood products from sustainable managed forests are burned to generate bioenergy, the biogenic carbon will be released as biogenic CO2 and absorbed by a new generation of growing trees. The longer the biogenic carbon is stored, the greater the environmental benefit as longer storage increases the sink for fossil CO2 emissions.

Carbon dioxide emissions from construction materials – mostly cement and steel – account for approximately 11% of all global emissions. Stora Enso believes that an increase in the use of low-carbon materials will lead naturally to an increase in the use of wood and timber. Its Lighthouse project in Joensuu, Finland, demonstrates what can be achieved by choosing wood as the main construction material and should give the naysayers pause.

Is net-zero carbon possible?

Joensuu Lighthouse is Finland’s tallest wooden building, rising close to 50m and providing 14 storeys of residential units (117 student apartments). It is also

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Global warming potential kg CO2e/m2/a A1-3 Product stage A4-5 Construction stage B1-7 Use stage C1-4 End-of-life stage A-C Total Additional information kg CO2e/m2/a D Benefits and loads beyond the system boundry Biogenic carbon storage

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net-zero embodied carbon through extensive wood product use and biogenic carbon storage

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88%

a net-zero-carbon pioneer because it is a high-rise building made almost entirely from wood.

The construction combines different wooden products, more than 2,000m3 of wood products to be exact, and both laminated veneer lumber (LVL) and cross-laminated timber (CLT) panels fitted to an LVL and CLT frame were used. CLT and LVL are high-strength solid engineered wood products that are used in structural applications, made up of multiple layers of thin wood assembled with adhesives that ensure a high strength.

Each floor took less than two weeks to construct.

All floors above the ground floor (which is made from reinforced concrete) are made from predominantly wood products, from sustainable forests, including: 1,200m3 of LVL for the walls, 900m3 of CLT for the floors and approximately 100m3 of other timber products.

In total, the wood products used to construct the Lighthouse Joensuu building store more than 1,600 tonnes of CO2 throughout its lifespan. Incredibly, the amount of carbon sequestrated by the timber used in the build equals the annual carbon dioxide emissions of approximately 700 passenger cars.

The lifecycle emissions of the Lighthouse Joensuu, and the carbon stored therein, were studied using the European Commission’s Level(s) reporting framework.

In fact, the project was an official EU Level(s) pilot. The Level(s) consist of six indicators, each designed to link the individual building’s impact with the sustainability priorities at European level. These indicators are: greenhouse gas emissions throughout the building’s lifecycle (as used on the Lighthouse Joensuu project), resource efficient and circular material lifecycles (also used on the Lighthouse Joensuu project), efficient

5.52 0.58 22.59 0.74 29.42 -4.04 -5.39

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INTELLIGENCE

JUNE 2020

“Carbon stored in wood is emitted back into the atmosphere as CO2 at the end of its useful life where it can be absorbed by growing trees”

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use of water resources, healthy and comfortable spaces, adaptation and resilience to climate change, and lifecycle cost and value.

The lifecycle assessment spans 60 years including all main building materials and installations, material transport and construction activities, the use phase and end-of-life scenarios. Carbon emissions are measured in four assessments: 1 Embodied carbon comprises the greenhouse gas emissions associated with materials and construction processes throughout the whole lifecycle of a building or infrastructure.

2 Upfront carbon emissions result from material production and construction phases of the lifecycle before the building or infrastructure is used.

3 Operational carbon emissions are generated by the energy used to operate the building or infrastructure.

4 Biogenic carbon storage refers to carbon removed from the atmosphere and stored as carbon in a wood-based product.

Timber construction brings less obvious carbonemission saving opportunities (upfront carbon emissions). For example, wood products typically have a fifth of the weight of conventional construction materials, such as concrete, they require fewer deliveries to site and potentially lower transport-related emissions. The wood elements on the Lighthouse required 50 truck deliveries compared with an estimated 270 deliveries that would have been required if concrete had been used to construct the entire building.

The embodied carbon of the building Level(s) promotes a life-cycle approach that goes beyond use-phase energy efficiency. The global warming potential indicator covers all greenhouse gas emissions from the building lifespan (material manufacture, construction, maintenance, renovation and deconstruction). The carbon stored in wood is emitted back into the atmosphere as carbon dioxide at the end of its useful life, where it can again be absorbed by growing trees. This circular carbon cycle is a key lifecycle difference between renewable wood products and non-renewable materials.

For the Lighthouse project, the results showed it had achieved 88% net-zero embodied carbon through extensive wood product use and biogenic carbon storage (see chart on previous page). It shows that the goal of net-zero carbon dioxide emissions during

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TIMBER CONSTRUCTION

Richard Harral, Technical Director at CABE: From a UK perspective The Stora Enso Lighthouse project brings the tensions between sustainability and building safety into sharp focus. For many parts of the UK the use of structural timber in the cladding of a building is now banned for higher-rise developments. There is an ongoing debate as to whether this is entirely proportionate.

But setting aside the impact of government regulation, it is clear that insurance and mortgage lenders’ risk appetite has shifted considerably and across a much wider range of buildings.

This suggests that there will be ongoing challenges for the increased uptake of timber in UK construction, although in many cases the need may well be for more robust evidence of performance rather than further product innovation. This will most likely need to extend beyond testing of material performance to more complex testing of performance in use as building systems.

Given the shift in insurance and finance markets, the onus would appear

to be on the product systems’ manufacturers to restore confidence.

For building engineers, the need to balance competing priorities in the design or assessment of buildings is nothing new. There are many areas where difficult decisions need to be made to get the best outcome overall. However, the pressing need to reform the construction sector so that it is capable of delivering building work with net-zero carbon emissions will increasingly require the use of materials and systems that are less familiar – and even more so once embodied carbon becomes part of the overall calculation of emissions (as seems likely over the next decade).

This requires engineers, designers and assessors to make more complex judgements.

Pressure to innovate will be intense, and it is clear that enabling innovation will continue to be an important part of achieving global climate change reductions. We do, however, need to learn the lessons of the recent past and exercise the precautionary principle – by emphasising caution and taking time to review decisions where the evidence of through life performance is not yet available – to reduce the risk of future systemic building failures.

construction can be reached almost fully when wood is chosen as the construction material.

“Lighthouse Joensuu is a fine Finnish example of how massive wood products can be used to build tall, impressive and sustainable buildings,” says Antto Kauhanen, Stora Enso wood products division’s Business Development Manager, “and anecdotally the first residents that moved in have praised the acoustical conditions in the building and the affect it has had on their wellbeing.”

The building was developed by Joensuun Opiskelija-asunnot Oy Joensuun Elli, the architectural designer was Arcadia Oy, the structural designer was Joensuun Juva Oy/A-Insinöörit and the contractor was Rakennustoimisto Eero Reijonen. The timber parts were machined by Timberpoint Oy and the Karelia University of Applied Sciences was responsible for wooden high-rise research and development.

For more information on the project, visit bit.ly/LighthouseJoensuu

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INTELLIGENCE

THERMAL IMAGING

Thermographic image 5

Thermographic image 6

Thermographic image 5: shows what the thermal readings would be in a good construction. The consistency of the orange colour across the wall surface indicates that the thermal insulation has been installed to a satisfactory standard to limit heat loss and so the wall temperature is uniform. It is normal for thermographic imaging to detect slightly lower temperatures at external corners of walls, both horizontal and vertical. This is caused by the slightly higher level of heat loss expected in these locations and is not a sign of a problem.

Thermographic image 6: shows a potential fault. The patch of darker colour indicates that part of the wall area in the corner is at a much lower temperature, indicating higher localised heat loss. The regular shape, together with what appears to be the structural timber, suggests that an area of insulation may be missing or has been poorly installed between the vertical studs.

No cause for alarm

2020 vision

Thermographic image 25: the bright colour of the roof tiles appears to indicate excessive heat loss through the roof, suggesting that the loft insulation is either missing or has been poorly installed. In fact, the higher surface temperature of the roof tiles is more likely to be due to the loft space being heated up during the day and the heat being retained as the external temperature falls at night.

The same is true for the bright yellow patch above the front door roof canopy, which suggests the cavity wall insulation is missing when, in fact, during the day sunlight may have been reflected onto the wall by the roof canopy, causing the temperature increase. The dark colour of the windows suggests the ambient external air temperature is cold and, as glass is reflective, it could be reflecting the sky temperature.

Herein lies the point of the guide, thermal imaging is a fantastic tool, but it is only really useful if undertaken by a thermographer; otherwise it may offer a distorted vision of a building’s thermal performance.

How to undertake and interpret thermal imaging

For a copy of the guide, visit bit.ly/Thermalimagingguide

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Thermographic image 25

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The guide gives good and bad examples of doors, ceilings, walls and floors. It also helpfully gives examples of typical variations in thermal images that aren’t cause for alarm, despite how they might initially appear (see image 25).

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IMAGE: GETTYIMAGES

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arly this year, the NHBC Foundation published Thermal Imaging Report Guide: how to interpret a thermal imaging report (NF86). Prepared

by Building Services Research and Information Association (BSRIA), the guide aims to identify good practice and aid clear interpretation of the information provided within a thermal imaging report.

Thermal imaging has long been used to give a non-invasive view at various stages of construction. It can show the thermal performance of the internal and external walls, roofs and surfaces (it cannot see through materials) by creating a visual map of the surface temperatures. This is made from thousands of temperature measurements taken by infrared-sensing equipment and displayed against a temperature scale. The warmer an object, the more infrared radiation it emits. A specialist thermal camera detects infrared radiation that is electromagnetic radiation (EMR) with longer wavelengths than those of visible light and, therefore, generally invisible to the human eye.

Thermal imagining is primarily used to assess the energy efficiency of new and existing builds and help identify areas of heat loss (such as gaps in the building fabric and the performance of windows and doors). Thermal imaging has also been used to identify water penetration into external cladding systems and can have other wider analytical applications.

As the guide points out, the correct settings of the specialist camera are crucial for an accurate survey, as is the employment of a suitably trained thermographer to conduct and interpret the results. The reasons for this include the need to take account of atmospheric pressures at the time of reading. It is also important that operatives understand the minute variations in colour and scale of the readings, to help understand the likely cause of the results (see images 5 and 6).

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INTELLIGENCE

JUNE 2020

Through the roof BUILDING ENGINEER

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Paul Trace from Stella Rooflight offers guidance on the thermal performance (U-values) of rooflights and what to look out for in the specification process

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ne of the most important elements of modern building materials is thermal performance, which is primarily understood and measured in terms of heat loss. In the construction industry this is commonly expressed as a U-value (the overall thermal transmittance of a product) or an R-value (the thermal transmittance of a system or a discrete product in a system). U-value calculations will invariably be required early on in the building strategy stage as they provide an indication as to how much heat loss a building is likely to suffer upon completion. The products used in the build are normally required to be tested and a figure for each component given.

One example of where this is an essential requirement is rooflights.

Thermal transmittance (U-value) is measured in units of W/m²K, which stands for Watts per metre square Kelvin. The lower the U-value the more efficient the construction is at keeping heat flow through the structure to a minimum. It is worth noting that it’s not just the building materials and products that have an impact on the thermal performance of a building, as both workmanship and installation

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standards can strongly affect the thermal transmittance. If insulation is fitted poorly, with gaps and cold bridges, then the thermal transmittance can be considerably higher than desired, no matter how good the individual products are.

Thermal transmittance (R-value) takes heat loss due to conduction, convection and radiation into account. The amount of heat conducted through a material of a given volume in a unit of time – i.e. the rate of conduction – is why the units are measured as W/K. There are guidelines in the UK, set out in Building Regulations Approved Document Part L (Conservation of Fuel and Power), which give the maximum U-value that materials and structures are allowed to have in a range of buildings, including domestic properties. It sets a national standard to ensure that homes must be built to a certain performance

level of energy efficiency for both the reduction of carbon emissions and the reduction of residents’ heating bills.

A true reading?

A U-value is one of the most difficult thermal measurements to calculate, so it is important that any figures are produced using reliable software from a bona fide source. When it comes to rooflight suppliers providing U-value figures for their products, we all want the lowest possible number to prove that our rooflights give the best thermal performance, which ultimately reduces heat loss for our customers. In the rush to be the best, it is not inconceivable that figures get a little massaged. It is always best to ask for a copy of the test performance report to ensure that a) the figures are genuine and b) that the figures were produced in the correct way.

“U-value calculations provide an indication as to how much heat loss a building is likely to suffer upon completion”

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THERMAL PERFORMANCE

One of the easiest ways to lower a U-value on a window or rooflight is to increase the thickness of the glazing. A decent double-glazed unit will give a centre pane value of 1.0W/m²K and a triple around 0.5W/m²K. There are some that offer quad glazing, which reduces this figure further.

However, it should be noted that reducing the U-value in this way will significantly

Stella rooflights are manufactured using high quality Marine Grade 316 stainless steel, which enables more glass per frame

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Aesthetics and other considerations

increase the weight of the product, the cost and also the depth of the rooflight profile.

If you are working on a listed building or in a conservation area, you may require a conservation rooflight design that should sit completely flush with your roofline. If you are looking to use quad glazing or modern bulky rooflights to improve thermal performance, this will most certainly be to the detriment of the building’s aesthetics.

There are a few exceptions relating to the thermal requirements in certain buildings, and it is always a good idea to take professional advice should your project fall into one of the following categories: i) Where the replacement roof windows are unable to meet the requirements because of the need to maintain the external appearance of the façade or the character of the building, replacement windows should meet a centre pane U-value of 1.2 W/m2K. ii) Buildings that are: listed in accordance with section 1 of the Planning (Listed Buildings and Conservation Areas) Act 1990; in a conservation area designated in accordance with section 69 of that Act; included in the schedule of monuments maintained under section 1 of the Ancient Monuments and Archaeological Areas Act 1979; used primarily or solely used as places of worship; stand-alone buildings with floor area less than 50m2; carports; temporary buildings with a planned time of use less than two years.

JUNE 2020

Despite being used in their millions across the country, it might surprise you to discover that there is no specific test for a rooflight. Instead rooflights are tested to BS EN ISO 10077-1:2017, which is a thermal performance test for windows, doors and shutters.

Does this actually matter?

Well, yes, it does because most rooflights cannot be used in the same way as windows, and this will result in a change to the U-value.

For example, the pitch of the roof will change the thermal performance of your rooflight. However, the testing of rooflight performance is based on either a vertical (above 60˚) or horizontal (0˚) pitch. Both positions are usually outside the maximum and minimum pitch that rooflight manufacturers recommend for their rooflight products.

There is quite a difference between the U-values given to rooflights at each end of the scale. For example, the Stella rooflight can achieve a U-value of 1.5 W/m²K in the horizontal position, but this improves to 1.1 W/m²K when used above 60˚. So, when you ask most companies what the U-value is for their rooflight, you can take a good guess which figure will be given? Most likely the more optimistic result – which is why it is important to either ask for both figures or to request data to support the figures quoted.

The design of a rooflight is also critical to the thermal performance. Most modern rooflights are produced from thermally broken aluminium, which is then clad internally with wood to provide very good U-values. While making the frames more thermally efficient, this approach also makes the rooflights chunky, which often results in them sticking several inches above the roofline and providing poor frame-to-glass ratios. It is not uncommon for some rooflight frames to make up over 40% of its overall size, which ultimately means 40% less light entering a building – finding the right balance in specification and design can mean making trade-offs between these features.

While the testing methods for obtaining a rooflight’s thermal performance could arguably do with an overhaul, a U-value figure remains very important for both choosing products and in the overall construction of a building. The lower the figure, the more thermally efficient a product or building is; and this can contribute to reducing heating costs, reduce carbon emissions and ultimately improve its energy efficiency. It is also important that the figures provided are genuine. It is advisable to request proof that U-values being quoted are not only correct, but are appropriate for the application that you are using that product. Nowhere is this more important than rooflights because of the current way in which these products are tested.

If you have any questions or require further technical information concerning the use of rooflights, please contact Stella Rooflight team on 01794 745445 or visit stellarooflight.co.uk

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INTELLIGENCE

JUNE 2020

Derbigum Olivine membranes have a naturally occurring mineral upper layer that neutralises CO2 via an irreversible chemical reaction when it comes into contact with rainfall

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Better living through chemistry Ben Green, Divisional Marketing Manager for Alumasc, discusses the installation of its carbon dioxide-neutralising roofing at Nottingham Trent University

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evelopments that design with environmental concerns in mind are becoming the norm. As well as teaching the effects of positive actions towards the environment, Nottingham Trent University (NTU) considers that the best way to press home the ecological and sustainability agenda to its students is through demonstration. To this effect, it has installed a new CO2 -neutralising roofing system.

Alumasc Derbigum Olivine roofing contains a top layer of Olivine, an iron-magnesium silicate that is a common, naturally occurring mineral. When CO2 in the atmosphere comes into contact with the roof as rainwater, it is absorbed and neutralised in a chemical reaction, the residue of which is water, silicon dioxide (sand) and magnesium carbonate. All these are

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ROOFING SYSTEMS

harmless to the natural environment, so when the rainwater rolls off the roof and reaches the drains, it’s carbon-free.

In addition, the roofing has a bituminous felt membrane system, 40% of which is recycled. Belgium company, Derbigum, recycles 4,000 tonnes of bitumen a year, and notes that the material suffers no loss in quality from the process (like gold, which can be melted and recast). The membrane is 7.27m long, 1.1m wide and 4mm thick. It can be applied as a single or two-layer system, and cold-bonded or welded to cover the necessary area. Once the roofing system has reached the end of its lifespan, it can all be recycled and reused.

The Olivine grains themselves decrease in size with each reaction. However they are large enough to last more than 30 years before having completely reacted.

Adding a second layer of Olivine grains increases the lifespan to more than 60 years. One kilogram of Olivine granulates has the capacity to neutralise 1.25kg of CO2 over 30 years.

Nottingham Trent University This ground-breaking technology has been used in the recent redesign and refurbishment of NTU’s Clifton Campus Library, which now features more than 1,000m2 of Olivine, providing a waterproof, BBA-approved, ecological roofing solution.

Durability and sustainability are also in evidence in other aspects of the design and specification.

This included Alumasc Rooflights with kerb design to prevent water penetration and domed glazing moulded from Marlon FSX polycarbonate, which has an impact resistance up to 200 times that of glass. The Harmer AV roof outlets and GX pressed aluminium gutters used in the project have the ability to drain up to 40% more roof area than conventional drains – a significant consideration bearing in mind the large surface area of roof and higher predicted peak rainfall arising from climate change. The membrane is guaranteed for 40 years, carrying the longest British Board of Agrément (BBA) certificate in the UK, and its high melting point ensures membrane stability in the hottest weather while the polyester/glass fibre reinforcement provides high tensile strength. The entire roofing system, including the gutters and drains, is 100% recyclable. Moreover, the Olivine granules have a green hue that makes this the next generation green roof in every respect.

For more on Alumasc’s roofing systems visit alumascroofing.co.uk and its water management solutions, visit alumascwms.co.uk

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INTELLIGENCE

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he development of the University of Northampton’s £330m purpose-built Waterside campus (featuring a burgeoning Waterside Enterprise Zone, a 20,000m2 Learning Hub, student accommodation and a new low-carbon Energy Centre) required more careful consideration than most new builds. Bordering the River Nene, and built on brownfield land once home to the old Northampton power station and a series of industrial warehouses, the 24-hectare site posed a series of development and design challenges, not least that its close proximity to the river deemed it at high risk of flooding.

Jon Williamson, Specification Manager at ACO Water Management, worked closely with the consultant engineers, Peter Brett Associates (PBA), on all elements of the drainage system. He notes that the development had to be

FLOOD-RISK SOLUTIONS

aesthetically appealing because of its location, but that it also, “had to be able to provide effective water storage contingency capacity in the event of a flood or periods of heavy rainfall to mitigate any significant damage to the campus”. The flood mitigation strategy centered on using channels with a high hydraulic capacity throughout the site and – where possible – integrating sustainable drainage system (SuDS) principles into the design.

For paved and pedestrianised areas in open view, a Brickslot channel drainage system was used. Designed as standard with a heelguard 10mm offset drainage inlet, ACO’s Brickslot (grating) when combined with MultiDrain channels provided discreet drainage because the vertical sides of the grating allow pavements to be laid directly to the unit’s edge. A number of the Brickslot channels also drained directly into swale outlets,

IMAGE: ALAMY

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“Another key area of the design identified by the consulting engineers,” says Jon, “given the volume of road infrastructure, was kerb drainage. Specifically, they needed to find a unit that would match the finish of the solid granite paving that would be used throughout the campus.”

ACO’s KerbDrain met both the structural design and hydraulic capacity criteria, and the company was able to match the surrounding granite.

For quieter roads and other areas such as car parks, ACO’s MonoDrain channel was used. It is a monolithic general-purpose channel drainage system made from high performance, recyclable Vienite® polymer concrete. Unlike other monocast solutions, its inherent strength means that it requires significantly less concrete haunching when being installed, which offers a £5/m per linear metre saving on installation costs.

Finally, a series of textured RoadDrain channels, also made from Vienite® polymer concrete and built to Load Class F900, were installed at the main entrance to the campus near the River Nene. The location is the primary point of access for campuswide deliveries and HGVs, and a major bus route for students travelling to and from the campus, which meant high loadbearing capacity channels were needed.

The campus combines aspirational architecture with sustainable build principles, so it was entirely appropriate that a sustainable approach to drainage was employed – a SuDS-focussed solution to a high flood-risk site.

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Kerb your enthusiasm

Kerb appeal

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Applying SuDS principles provided a practical, yet attractive, solution at a high flood-risk beauty spot

located throughout the site to help facilitate the release of surface water back into the local environment in a controlled way.

Swales are shallow drainage channels with gentle side slopes in the ground where water running off a site can collect and soak away. Swales can be used to channel run-off from roads, yards and car parks, or to carry water through a site.

Crucially the presence of swales throughout the site not only bolstered the site’s overall water management capabilities, but further improved the aesthetics and biodiversity of the campus by boosting the volume of green spaces.

ACO has a broad portfolio of watermanagement solutions, visit aco.co.uk for more information

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INTELLIGENCE

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uropean cities need to transform their infrastructure if they are to meet the emerging challenges posed by the effects of anthropogenic climate change. From a water perspective, this means there is now a higher probability of flooding from heavier precipitation and storm surge, but also an increased risk of not having enough water available to keep taps flowing.

Further issues arising include flood damage to buildings and other street infrastructure; sewer overflows polluting watercourses and water bodies, and the declining quality of lakes, rivers and reservoirs. Biodiversity is also at risk, along with public health and the psychological wellbeing of those affected by extreme weather events.

UN-Habitat’s Urban Resilience Hub defines urban resilience as: “The measurable ability of any urban system, with its inhabitants, to maintain continuity through all shocks and stresses, while positively adapting and transforming toward sustainability” – and a key part of that ability will be technological. It is against this background that Isle set up its Urban Resilience Technology Approval Group (UR TAG) in 2019.

The group has spent the past year actively identifying and piloting water technologies that help transform cities’ infrastructures as they adapt to climate change. Designing and structuring the urban environment to absorb and capture as much rainwater as possible can reduce and prevent floods.

The harvested rainwater can also be repurposed for irrigation and greywater domestic use.

China is leading the way to sustainable drainage systems (SuDS) at city scale, with plans for sponge cities where 80% of the country’s urban centres harvest and reuse 70% of rainwater. Sponge cities are promoted as an holistic approach to rainwater management, not just limited to China, but also taking place in the USA, UK and across other European projects. The goal is to buffer rainwater at its place of origin. Green elements, such as swales, tree-drains, and green roofs and façades help to evaporate, store and infiltrate the rainwater, which effectively reduces the outflow. We see these holistic approaches to managing a city’s water as a strong trend across the world – not only one single solution for one problem, but rather an integrated approach to tackling several challenges.

Building SuDS at scale and driving urban resilience requires significant investment, which is another reason UR TAG is so important. Utilities and

Pooled knowledge Isle’s Technology Consultant Sylvia Schuster explains why managing the effects of climate change requires urban transformation, specifically for water management

“Designing the urban environment to capture as much rainwater as possible can reduce and prevent floods”

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18/05/2020 12:49

WATER MANAGEMENT

Bosco Verticle – nature-based urban resilience infrastructure in Milan, Italy

JUNE 2020

municipalities can pool project experiences, share best practice and collaborate on technology trials so that they can learn from each other, avoiding unnecessary repetition and costly mistakes.

23

Current UR TAG members include HSY, the Helsinki Region Environmental Services Authority; together with MM, which manages water and wastewater services in Milan, Italy; and the Belgian utilities Aquafin and WaterGroep. Isle Utilities and UR TAG also have a partnership with CALL Copenhagen – the Climate Change Living Lab – which enables Danish cities and utilities to be introduced, too.

Members meet to exchange knowledge and expertise.

For example, February’s excursion to Antwerp, Belgium, saw members exploring the city’s urban resilience infrastructure.

Aquafin’s Els Liekens notes: “To be effective, we need to improve research and innovation, and by using UR TAG we have a clarified view of the available technologies and don’t have to invent it all again. The regular meetings are a useful opportunity to network and see how other cities and utilities are managing their climate resilience challenges and keeping on track with interesting solutions.”

Isle uses an online portal that lists all the technologies it has screened. All UR TAG members get access to that database where they can see detailed information about technologies and are able to exchange knowledge about them. Excursions to sites where innovations are being used offer valuable insight and allow members to ask questions of those using the technology – including the applicability of the solutions in their respective organisations and countries. Discussions can range from the need for

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BUILDING ENGINEER

Meeting of minds

18/05/2020 12:49

INTELLIGENCE

WATER MANAGEMENT

End-user forum A proposed technologies list is prepared before each UR TAG event, following a careful due diligence process, and members can vote for their top five. These companies will then be invited to pitch at the event.

The events usually take place over two days and have included an excursion in the host city to see initiatives that have already been implemented. Presentations of case studies are shared before interactive sessions take place. The technologies are collaboratively reviewed in a Q&A process, after

which members discuss the technology complete feedback forms. Feedback is anonymised and sent back to the tech company, which then has the opportunity to reply to open questions. There may be interest by one or several parties for a trial.

There are also strategy sessions and technology updates. It is important that it is an end-user forum, where the members are comfortable sharing. After all events, a summary with the highlights of the day are shared via Isle’s TAG portal.

JUNE 2020

Urban Resilience TAG meetings are an opportunity to pool project experiences, share best practice and collaborate

BUILDING ENGINEER

24

a sophisticated hydraulic model at the start of software testing to the interest in real-time live web services for precipitation events.

A watershed moment With regards to stormwater management, integrated solutions with nature-based elements are preferred. If you have a neighbourhood that is constantly flooded, the first step is to map out the hot (or rather wet) spots where flood events are most problematic. A variety of technologies can then be considered to mitigate impacts. Permeable pavements instead of non-permeable asphalts could allow the stormwater to infiltrate into the ground – either to a storage tank or to the groundwater aquifer. We have seen permeable pavement technologies that only buffer the water, but there are also technologies that include a filtration stage. Modular wetland technologies incorporating filters for heavy metals can be installed at parking areas. Stormwater can be heavily polluted; but by treating it on site, the same water can be reused for irrigation, for example. With combined sewer overflows, there are several hardware technologies to reduce the risk of pollution to surrounding water sources, such as automatic gates that close when the water reaches a certain level.

There are smart software solutions that allow users to monitor their whole network, sometimes the entire urban water cycle, combined with a real-time live

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Urban Resilience practitioners on an excursion during a platform meeting held in Rotterdam, Netherlands

forecast of precipitation. The software could monitor water storage capacity and send out flood risk alerts and suggested actions to take. The group has also seen software that analyses recent weather data to identify drought risk and suggests the best actions for sustainable water resource management.

Enhancing biodiversity improves urban resilience, and by increasing green areas in cities not only increases the biodiversity, it also improves quality of life. UR TAG has witnessed systems that enable urban trees’ roots to grow better by allowing stormwater to infiltrate into the ground. It has also reviewed various green wall and green roof concepts as well as floating ecosystems for urban water bodies.

Essential to all these measures is citizen engagement and participation. If the people living in the neighbourhood and local community are engaged in the planning process, they are more likely to feel ownership long after the project’s implementation.

The focus of the UR TAG technologies depends on the interests and needs of its members, such as sustainable decentralised energy systems, alternative water sources or greywater recycling. This is assessed after every meeting to help the process of screening technologies. Until now, there has been a focus on holistic water management. However, because of Covid-19, the group is exploring technologies that help build resilience towards future pandemics, such as those that enable more remote working. UR TAG is looking into natural disaster resilience, too. Sharing experiences of different innovations and providing an environment to discuss their applications is a very positive approach to meeting the challenges of climate change.

Isle is an independent technology and innovation consultancy that brings together technical and commercial specialists. Through its global innovation forum, the Technology Approval Group (TAG), it identifies emerging technologies, connects expertise and investment to accelerate their adoption. For more information, visit isleutilities.com To join UR TAG, email bastian.piltz@isleutilities.com

18/05/2020 12:50

INTELLIGENCE

LED LIGHTING

LEDs’ energy efficiency is in part due to their use of directional light downwards.

Fluorescents project light in many different directions – including towards the ceiling – so they waste the light

LEDs bring potential energy savings of

Fewer LED lights are needed to achieve the same level of brightness given off by fluorescents and incandescent lights. Fewer lights will reduce energy consumption

80%

Fluorescent lighting has a shorter lifespan than LEDs – as much as Initial outlay costs are typically paid for within

LED luminaires are designed to replace fluorescent fittings in more ways than one LEDs need virtually no maintenance and last up to six times longer than other types of lights

W

ith businesses working to improve their energy efficiency and help tackle climate change, it’s becoming harder to justify keeping traditional fluorescent and incandescent lighting in buildings when LEDs are more than proving their worth. However, for many, the initial upgrade to LEDs can be a daunting prospect, mainly due to the higher upfront costs, disruption and installation. Here are some figures that may incentivise the change.

Further information on energy-saving LED lighting schemes is available at ecolightinguk.com

LED lights draw much less power than traditional lighting; a typical 84 watt fluorescent can be replaced by a 36 watt LED to give the same level of light. Less energy use reduces the demand from power plants and decreases greenhouse gas emissions

25 LEDinfo.indd 25

5%

is wasted as heat

LEDs maintain their brightness throughout their life unlike fluorescents, which suffer lumen depreciation and flicker or buzz as they begin to FAIL

25 BUILDING ENGINEER

Lighting by numbers

of the energy in LEDs is converted into light and only

JUNE 2020

3 years

24,000 hours shorter

95%

80

Hg

mercury (200.59)

LEDs are free of harmful chemicals such as mercury, making them safer to use and dispose of

LEDs create a safer working environment, as better quality light improves visibility, reduces accidents and eye strain issues

18/05/2020 12:50

JUNE 2020

INTELLIGENCE

SuDS standards Martin Lambley, Product Manager for stormwater management at Wavin, highlights the fundamentals of Sustainble Urban Drainage Systems

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N

ew Design and Construction Guidance for the water sector was released in April 2020.

For the first time, it set out standards for sustainable drainage systems (SuDS), redefining the types of assets that water companies will be required to adopt and maintain and that contractors will have to install.

There’s never been a more crucial time for building engineers to understand what SuDS are and the benefits they bring to a development and the built environment.

SuDS are specialist drainage systems that help to reduce the risk of surface flooding. The concept is not new to the industry – SuDS have been around since the early 1990s – however, as sustainable development is becoming more of a prominent focus, SuDS are only now starting to be taken seriously.

Traditionally, stormwater has been managed through natural infiltration where water gathers on existing vegetated

IMAGES: IMARK COVENTRY, ALAMY

BUILDING ENGINEER

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18/05/2020 15:14

SUDS STANDARDS

Hard SuDS are appropriate for projects with restricted space, such as those in urban areas

patches of land and soaks through into the ground. However, in urban areas this isn’t always feasible. The tarmacking and cementing of outdoor space, such as pavements and car parks, make them impermeable and the water has nowhere to drain. If not managed effectively, this can easily increase the risk of flash flooding during storms and extreme rainfall, which are on the rise.

Rather than using pipes to collect rainwater and release it into rivers, which is no longer considered practical or sustainable, urban planners are having to consider smarter drainage systems for extreme weather. This is where SuDS come in. They help to collect surface water and release it into the environment at a manageable rate.

SuDS: the variations

Read Design and Construction Guidance for the water sector at bit.ly/DesConGuide

27 BUILDING ENGINEER

For more on Wavin’s sustainable drainage systems, visit wavin.co.uk

JUNE 2020

Soft SuDS use purpose-built green landscaping to manage water within a site

SuDS typically fall under two categories – soft SuDS and hard SuDS. Soft SuDS are an ideal solution for holding back water for later release. They use purpose-built green landscaping, such as swales and soakaways, to manage water within a site and massively encourage biodiversity.

They can sometimes take up considerable space, which limits their viability.

Hard SuDS are large storage tanks buried underground, so are appropriate for projects with restricted space, such as those in urban areas. Collected stormwater enters directly into the tanks and then is released back into the surrounding soil through infiltration, or at a controlled rate into the drainage network or local watercourse.

In the past couple of years, the UK government has trialled and revised policies designed to improve rain and stormwater management, contributing to overall sustainability. The Design and Construction Guidance, which took effect in April, is the most up-to-date version of these and supersedes all other guidance.

Unsurprisingly, SuDS play a major role; they can significantly reduce the risk of flooding and stormwater management, they also improve factors such as air quality, biodiversity and water quality. This is, in part, due to their larger water storage capacity and their ability to reduce the rate of pollution. The guidance defines only some SuDS assets as adoptable by water companies (see below), setting out clear standards for their integration into the urban design process.

It means that designers will be required to consider the installation, health and safety, maintenance and access requirements of both hard and soft SuDS as part of their designs. With the growing threat of climate change and towns and cities continuing to grow at a rapid pace, it’s more important than ever that local authorities, planners and engineers work in unison with developers, installers and manufacturers to find the most suitable solutions to water management.

Definitions of SuDS assets

“As sustainable development is becoming more of a prominent focus, SuDS are only now starting to be taken seriously”

26-27 Suds.indd 27

Adoptable assets If it is constructed for the drainage of buildings and yards appurtenant to buildings If it has a channel (a depression between banks or ridges with a definite boundary) If it conveys and returns flows to a sewer or to a surface water body or to groundwater If it has an effective point of discharge, which must have lawful authority to discharge into a watercourse or other water body or onto or into land.

As with conventional piped systems, this right to discharge must be secured by the developer and transferred to the water company on adoption.

Excluded assets Watercourses as defined in law (these include rivers, streams and can include some ditches) Components built primarily for the drainage of surface water from streets or for the drainage of land Components built to manage groundwater Components which are part of the structure of a building or yard (green roof, pervious driveway or guttering and rainwater pipes attached to the building) Components which are an integral part of the structure of a street (a pervious street or the channel formed by the kerb of a conventional road or a channel formed by a depression in the centre of a street).

18/05/2020 15:15

INTELLIGENCE

JUNE 2020

L

BUILDING ENGINEER

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ocated in the green belt on the edge of a country park and on a site reclaimed from industry, the new heritage centre is a part of the Land of Oak & Iron project, led by Groundwork NE & Cumbria, which celebrates the industrial, cultural and natural heritage of the Derwent Valley and surrounding area. The centre focuses on the revolutionary iron works established on the site in the 1690s as one of the largest suppliers of ironware in Europe at the time. It was supported by the National Lottery’s Heritage Lottery Fund and the Rural Growth Network, which complemented investment from Groundwork and Gateshead Council.

The proposal also had to overcome the hurdles of building on reclaimed ground, site conditions, flooding risk, its green belt location, limited budget and time constraints. The flood-risk assessment determined the appropriate ground-floor level, taking into account future climate change and weather conditions. This informed the overall design and provided the opportunity to develop the building above the existing capping layer of the reclaimed site.

The water wheel-shaped design concept by Matthew Glover was inspired by the revolutionary iron works at Old Winlaton Mill, which – by 1707 – was one of the first, fully integrated, iron founding and goods manufacturing plants in Europe. The concept was chosen by local residents following a competition involving 35 post-graduate architecture students from Northumbria University. Gateshead Council’s design team (architecture, below ground structure, quantity surveying, mechanical and electrical engineering), Groundwork (the client’s project management, landscape design and interior fit out) and Esh Construction (contractor and superstructure design) brought Matthew’s concept to life.

Supporting a three-quarter, waterwheel-inspired building footprint on contaminated reclaimed ground, without penetrating the existing capping layer or reaching the bedrock some 20m below, presented a significant challenge. This was overcome by extending the raft slab across the courtyard area.

By doing so, both gable ends were tied together, reducing the risk of differential movement. To manage the risk associated with the site’s ground contamination, the intended specialist combined hydrocarbon, gas and damp-proof membrane was later substituted with an active air-blanket system by the contractor.

Living history The award-winning Land of Oak & Iron Heritage Centre is a fine example of sustainable conservation

Aesthetics and practicalities Since the conceptual shape of the building had already won the hearts and minds of the local community and the planning authorities, the large envelope-to-floor area ratio posed an additional challenge. A fabric-first design approach was taken within the budgetary constraints of the project resulting in EPC Rating B being achieved. The selected MMC utilised a steel portal frame in combination with insulated timber frame panels and timber warm roof construction. The building envelope was completed with untreated Western Red Cedar external cladding,

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The visitor centre showcases the site’s history

18/05/2020 15:15

LIVING HISTORY

would temporarily store the surface water and delay its discharge with a view to contribute to the mitigation of the flood risk As part of the water management, there was the need for a green roof instead of solar PV panels.

Equally, solar PV panels were not considered acceptable as there was a possibility for undesirable light reflection onto the village above Due to the ground contamination there was a need to minimise any interference with the existing clay capping layer of the contaminated soil. Installing horizontal or vertical pipes for ground source heat pumps would have resulted in interference and potential release of contaminated material or gases.

This also ruled out a wind turbine, which would have required a foundation in excess of 20m.

28-29 IronOakHeritage.indd 29

29 BUILDING ENGINEER

“The water wheelshaped design concept was inspired by the revolutionary iron works at Old Winlaton Mill”

JUNE 2020

aluminium-framed, double-glazed units, green roof and the rusted mild steel fins/paddles.

The open shape of the building allows ample opportunities for natural lighting and ventilation, while the polished concrete screed and the green roof provide thermal mass. Due to the following site constraints, it was not viable to implement renewable energy generation options: The site is located on reclaimed contaminated ground in a flood-prone area within the green belt and in close proximity to a river. As a result of the surface-water flooding risk, it was necessary to build up the ground under the building so the ground floor is above the anticipated flood level.

This was done in conjunction with measures that

Due to the challenging site and ground conditions, it was considered most cost effective to use condensing gas boilers controlled by a building management system. This allows the building heating system to be weather compensated (heat flow temperature varies with the external temperature) and provides an optimised on/off control. All fans are controlled by local passive infrared detectors and LED lighting is used. The infrastructure was provided for charging of electric vehicles in the near future, too.

The single-storey building’s green roof minimises the impact on the local biodiversity in the area, as well as lessening the visual impact of the roof if viewed from higher ground. The green roof, permeable hard paving surfaces around the building, and permeable road surface in the overspill car parking, are all part of a system designed to attenuate and mitigate the impact of surface water discharge on the site. The building is complemented by the landscaping works, enhanced by artwork and the provision of additional car parking to meet visitor numbers.

Hearts and minds The limited preconstruction timescale was made even more challenging by the requirement that a contractor should be selected through open tender before the funding could even be considered.

Since opening in September 2018, the centre has become a focal point for visitors, as well as a catalyst for further improvements in the area. Between September 2018 and January 2020, the Land of Oak & Iron Heritage Centre attracted 132,332 visitors, supported 18 part-time jobs (9.5 FTE), of which 14 are held by local people, and has provided opportunity for 18 local business to supply and offer their products for sale.

The Land of Oak & Iron Heritage Centre won the 2019 CABE New Build Award, a 2019 Silver (Public Building) Green Apple Award for the Built Environment and Architectural Heritage, the 2019 Best Small Commercial Project LABC Northern Building Excellence Award, was Highly Commended (Sustainability) at the 2019 CABE Built Environment Awards, and Commended at the 2019 RTPI North East Planning Excellence Awards.

For more information about the project, visit landofoakandiron.org.uk

18/05/2020 15:15

INTELLIGENCE

P

olypipe, manufacturers of piping, water and climate management systems, has won a Green Apple Environment Award for its smart roof research project, installed at the company’s plant in Aylesford, Kent.

The Smart Roof 2.1 research project has been underway since 2017 and aims to determine the hydrological, thermal and biodiverse functioning of blue-green roof systems in the urban environment.

The prime goal of the system is to harvest and store as much rainwater for capillary plant irrigation as possible and only use potable (drinking) water in the case of extreme or prolonged droughts.

The greening outcome is that the system

has a higher urban cooling capacity, reduces rainwater discharge run-off rates to sewers and enables a wider plant species selection due to improved water availability.

The company took the decision to install a blue-green roof when re-roofing to test and demonstrate the viability of retrofit green infrastructure. Not only did the blue-green roof encourage biodiversity and prove a valued leisure space for employees; the intelligent, water-management system also optimised greening, increased water usage efficiency and reduced waste, and managed extreme weather events. It proved a micro-model of the water management challenges cities

face, along with the issues of suitable, sustainable urban landscaping.

Smart system The system comprises a drainage sub-base replacement with sedum top layer and an isolated instrumentation cell to automatically monitor and manage water supply to ensure optimum soil moisture, temperature and salinity conditions, which allows the bluegreen roof to flourish. The control and monitoring systems are operated remotely online via a smartphone, tablet or PC. Capillary cones – unique to the sub-base platform – draw stored rainwater upwards to irrigate the

JUNE 2020

Blue sky thinking Polypipe is acknowledged as a Green Champion for its intelligent, water-management roofing system

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ENVIRONMENTAL BEST PRACTICE

blue-green roof, while sensors within the cells monitor available water levels.

If a pre-determined low set-point is reached, the system operates a solenoid valve to add water from a rainwater recovery tank until the desirable level is reached. During high-rainfall events, excess water in the wet cell spills into the raft. When the tank reaches capacity, this water overflows to the drain.

The results of this smart management of water collection included: Higher diversity in plant and insect species Reduced average annual water shortages for sedum-dominated vegetation Increased evaporation reducing run-off and waste-water discharge to ground systems Increased building cooling capacity.

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“The blue-green roof proved a micro-model of the water management challenges cities face”

JUNE 2020

The storage of precipitation and capillary irrigation of the roof vegetation proved to be an effective measure for increasing total annual evaporation. Increased storage reduced average annual water shortage for

sedum-dominated vegetation from roof applications. MDPI’s Evaporation 28% to 4% and for a grass/herb vegetation from (Blue-) Green Roofs: Assessing the from 29% to 12%.

Benefits of Storage and Capillary Irrigation Installing a maximum 80mm storage (at bit.ly/MDPIbluegreen) provided the and capillary irrigation system increased only evidence to support blue-green the mean annual actual evaporation with roof thesis. For this reason, Polypipe staff 101mm/year (grass/herbs) and 96mm/year and the local university carried out their (sedum). This also means that hydrological own research into invertebrates and the performance in the sense of evaporating suitability of different plants for the site. precipitation water instead of discharging Overall findings from the invertebrates this water into the sewer was greatly study showed significant activity of improved by the storage and capillary pollinators around flowing plants (wet cell) irrigation system. compared with the rest of the roof area, Monthly averaged run-off from a and there are clear preferential trends capillary irrigated roof with 80mm storage within vegetative zones on the roof. is only half that of a conventional roof This could well be a preference for with sedum vegetation. With grass/herb blue-flowering plants. However, taking vegetation, this into considerations difference is even the other patterns larger resulting in that have been GREEN CHAMPION almost no discharge observed, the study in May and June, and would suggest that Polypipe was recognised less than one third the this is simply a result as a Green Champion for discharge in July and of preference Environmental Best Practice.

August annually. The for well-watered The Green Organisation’s mean annual available flowering plants over annual awards recognise, water for irrigation the sedum mat. reward and promote from precipitation A beehive has also environmental best practice. increased to 515mm been introduced For more details, visit (88% of evaporation (named the thegreenorganisation.info potential) for grass/ POLYnator Site) herbs vegetation and the local HSE and 386 mm (96% manager trained of evaporation as the designated potential) for the beekeeper. Last sedum-dominated year even saw the vegetation. first collection of Grass/herbs Polypipe honey. Staff vegetation needs are encouraged to additional irrigation increase the bee water during the population, thereby summer months to prevent complete attracting other insects and birds, to dehydration and a long recovery period make the site more sustainable. While during which the plants are not transpiring. the project provided a valuable research With on average 70mm – and in dry model for blue-green roofs and a valuable years 150mm – of additional irrigation space for wildlife, it brought wellbeing annually, grass/herbs vegetation becomes benefits to staff, too. Many use the seating sustainable under the current climate area during the day and report a greatly assuming an 80mm storage level and improved environmental awareness. capillary irrigation.

A second research project is underway Besides the extra cooling capacity, such based on the Polypipe blue-green roof vegetation provides additional advantages and will consider the use of stored water such as a higher diversity both in plant for business use (eg WCs), cooling solar and insect species. This creates more panels and its insulation effect in winter. natural vegetation that sustains native The Water Management Solutions Team biodiversity, making the roof look like formed in 2007 after identifying a need a meadow rather than the well-known within the UK construction industry sedum-dominated vegetated roofs. for engineered sustainable drainage solutions. It researches innovations to meet the global challenges of carbon Biodiversity reduction and water management.

Currently, no design or installation standards exist for blue-green roofs, and existing flat roof standards For more information, visit somewhat contradict the blue-green polypipe.com

18/05/2020 17:48

INTELLIGENCE

Set for change

JUNE 2020

Nina Cardinal, National Technical Manager at Hanson Cement, discusses how cement and concrete can be more eco-friendly

BUILDING ENGINEER

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G

lobally the cement industry alone accounts for 7% of CO2 emissions, while in the UK this figure is 1.5%.

It is no secret that the production of CEM I Portland cement (PC) is energy intensive and produces CO2. It is for this reason that many manufacturers have invested heavily to improve the efficiency of the production process and increase the amount of alternative fuels used to power the kilns.

Hanson Cement is taking part in a research project funded by the Department for Business, Energy and Industrial Strategy (BEIS). It is looking at the potential for hydrogen and plasma technology to reduce carbon emissions through switching away from fossil fuels, which could lead to cement and lime kilns operating with a net-zero carbon fuel mix. Its Ribblesdale cement works in Clitheroe, Lancashire, is the site of trials to demonstrate the zero-fossil fuel operation using hydrogen and biomass fuels in the cement kiln. The project’s results will be shared with wider industries to maximise the environmental benefit of the technology, which could save around two million tonnes of CO2 a year if implemented across the UK cement industry; equivalent to the annual emissions from 266,000 households and reducing UK greenhouse gas emissions by 0.6%.

Cutting CO2 emissions and conserving natural resources are obvious priorities for everyone involved in the construction industry. In the UK, Hanson has already achieved a 30% reduction in CO2 emissions since 1990 across the business, and has set an ambitious new target of a 50% reduction by 2030.

GGBS In addition to the use of alternative fuels, the use of products to replace some of the cement content in concrete, grout and mortar is also helping to significantly reduce CO2 emissions. One of the most effective alternatives to PC is ground granulated blastfurnace slag (GGBS). There are environmental

globally the cement industry accounts for

11%

of CO2 emissions

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18/05/2020 15:17

GGBS APPLICATIONS

Flood defence walls at the New Cut River in Ipswich used concrete containing up to 70% GGBS

Environmental issue

Measured as

Impact One tonne of GGBS1

One tonne of PC

Climate change

CO2 equivalent

0.08 tonnes

0.86 tonnes

Energy use

Primary energy2

1,390 MJ

4,200 MJ

Mineral extraction

Weight quarried

0

1.35 tonnes

1. No account has been taken of the impacts of iron making because the slag is created regardless of whether or not it can be used.

2. Includes energy involved in the generation and distribution of electricity.

32-33 HansonCement.indd 33

GGBS case study Almost 5,000m3 of concrete containing up to 70% GGBS have been used to construct a 20m-wide tidal barrier gate and piled flood defence walls at the New Cut River in Ipswich. The £21m project for the Environment Agency will protect around 2,000 properties that are at risk of flooding.

In total approximately 1,000 tonnes of GGBS were used in the project, saving 780 tonnes of CO2 emissions, which is equivalent to taking around 170 cars off the road for a year. The use of GGBS also enhanced the durability of the concrete, as concrete containing GGBS has a finer pore structure, reducing its permeability and making it more chemically stable and resistant to sulfate and chloride attack. The main barrier structure also required a low-heat concrete due to the scale of some of the pours, which were up to 730m3. Using GGBS in the mix reduced the heat of hydration, protecting the structure from early-age thermal cracking.

There is little doubt that, within the construction industry, cement and concrete production have been responsible for a significant contribution to CO2 creation globally. It is time now, for these industries to innovate and invest in change.

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Comparison of environmental benefits of GGBS and Portland Cement (PC)

The use of GGBS also increases the long-term durability of concrete, further cutting a project’s environmental impact by reducing the amount of repair and maintenance needed, and extending the service life of concrete structures. It provides: Enhanced resistance to sulfate attack (both the ettringite and thaumasite forms) Lower ingress of chlorides into the structure Minimised risk of alkali silica reaction Better resistance to acid attack Lower propensity to delayed ettringite formation Reduced risk of thermal cracking.

JUNE 2020

benefits to be gained from its use both in its production and throughout the life of the structure.

Portland cement is made by mixing calcium carbonates (eg limestone, chalk) with silica and aluminates (such as clay, marl or shale). They are burned in a rotating kiln at a temperature of 1,450°C and, during the process, the calcium carbonate decomposes to calcium oxide and CO2 is released. At the same time the carbon in the fuel used to power the kilns combines with oxygen to give off further CO2.

The manufacture of GGBS, however, requires less than one-third of the energy and produces less than 10% of the CO2 emissions. This is because it is a byproduct of the iron-making industry: slag is produced simultaneously with iron in a blast furnace and is an inevitable consequence of the iron production. For a comparison of the environmental impacts of GGBS and Portland cement see below.

To optimise the cementitious properties of the molten slag leaving the furnace, it is cooled rapidly before being dried and ground to produce a fine white powder that has similar characteristics to those of Portland cement. Energy is only used in the drying and grinding process as the power used in melting is all allocated to the iron produced.

The major use of GGBS is in ready-mixed concrete, with more than a third of all UK deliveries containing the product. Replacing one tonne of CEM I Portland cement with GGBS in a concrete mix reduces the embodied CO2 by approximately 780kg.

GGBS can replace a substantial part of the normal PC content – generally about 50% and up to 95% in

special applications – and is used in other types of concrete, including site-batched and precast, mortar and grout.

It can be used anywhere concrete is needed – from sustainable housing development and soil stabilisation to wind farms and road building – and is typically used in major construction projects such as bridges and sea defences. There are also other environmental benefits: GGBS does not require the quarrying of new materials and the slag used will not be disposed of as landfill.

Each year, the UK uses more than two million tonnes of GGBS as a replacement for cement, which: Reduces CO2 emissions by almost 1.56 million tonnes Reduces primary energy use by 1.6 million MWh Saves approximately 2.7 million tonnes of quarrying.

Hanson’s parent company HeidelbergCement is one of just 179 companies worldwide to be recognised for the action it is taking to reduce its impact on the environment with a place on CDP’s A-list for climate change. For more information, visit hanson.co.uk/en

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INTELLIGENCE

HEATING TRIALS

Heating trials

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nergy Systems Catapult runs innovation trials in its Living Lab – where 100 homes spread between Newcastle, Manchester, the West Midlands, Gloucestershire and Bridgend in Wales are fitted with smart heating systems that provide room-byroom temperature control and a wealth of data on consumer behaviour and the thermal performance of the home.

Energy Systems Catapult created a heat-as-a-service offering called a Heat Plan – where instead of buying units of energy (kWh), consumers buy hours of warmth in their home called Warm Hours.

In an industry first, two British companies successfully trialled the sale of Heat Plans to consumers. Baxi Heating UK trialled mobile phone-style bundles combining heating system and energy bills for a fixed monthly price. Bristol Energy trialled selling fixed price and pay as you go (PAYG) Heat Plans.

In addition, Energy Systems Catapult also tested the performance of hybrid heating systems that combine traditional gas boilers with an electric heat pump.

Dr Matt Lipson, Consumer Insight Business Lead at Energy Systems Catapult, said: “The UK has a target of achieving net zero emissions by 2050, yet only about 5% of UK homes currently have low-carbon heating, compared to 85% with gas boilers.

Low-carbon heating is simply a step into the unknown for most households.

Consumers have concerns about their ability to get warm and comfortable at an affordable price and how to fix the system if it breaks down. Switching to new forms of purchasing can help people become more comfortable with longer-term switching to low-carbon heat sources.

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“[The Heat Plan] allows people to schedule and budget for a specific number of Warm Hours – giving them the temperatures they want, in the rooms they want, at the times they want – for a fixed weekly or monthly price… then when it comes time to replace their gas boiler, they will be more confident of switching to a lowcarbon heating system like a heat pump, district heat network or hydrogen boiler.”

The results Of the 20 households in the Baxi Heating UK trial, ten liked the mobile-style bundle and wanted to continue, and one accepted the offer of a new boiler installation. The Bristol Energy was trialled in 85 Living Lab households and offered two Heat Plan options. Using consumers’ own data, one trial priced for a fixed number of Warm Hours based on their existing heating schedule and the other trialled a PAYG option with a price per Warm Hour. All those who trialled the different plans and were in favour of switching cited improved control and comfort, and certainty of price.

Energy Systems Catapult has also undertaken trials on a hybrid heating system (combining a heat pump with an existing gas boiler), which found that: More than half of households asked in the Living Lab had never heard of heat pumps Heat pumps were installed in five of

the 100 homes in the Living Lab, creating a hybrid system Hybrid heating systems achieved the same temperatures and levels of comfort as the gas boiler alone Heat pumps delivered between 6% and 63% of the heating across the five different homes (6%, 17%, 44%, 59% and 63%) depending on how each household used their smart controls The household utilising the heat pump only 6% of the time increased that figure to 51% with some simple advice on reducing the number of manual overrides to their heating schedule, which would force the boiler to kick-in Four of the five homes trialling the hybrid system were open to removing their gas boiler and relying entirely on a heat pump if they could buy their heat as a service, such as a Heat Plan. One customer commented: “You expect to have a boiler to heat the house… (most people) don’t even realise there’s the option of any other form of heating.

When the boiler’s old you don’t think ‘is there any other alternative?’. You think ‘the boiler’s old, I’ll replace it with another boiler’.”

Read the full findings of the 2018/19 Living Lab Winter Trial at bit.ly/BEHeatTrial, or to understand how to increase the appeal of heat pumps, visit bit.ly/BEHeatPump

IMAGE: ISTOCK.COM

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Can customers be persuaded to view heat as another supplied utility rather than as the result of supplied utilities?

An energy research company and two British energy firms decided to find out

18/05/2020 15:18

INTELLIGENCE

A

system will destroy a significant percentage of any viral elements passing over the panels.

Viruses are extremely small particles and as such are able to penetrate even the highest-efficiency filters.

(The Covid-19 virus’ 0.06-0.14 μm size range ensures that a percentage of virus particles will pass through even a 99.97 HEPA filter.) If the ventilation system’s air-cleaning capability is enhanced with a Genesis PCO system, particle size becomes unimportant since the virus is being reduced by a chemical oxidation process. Destroying the pathogen lowers risk liability versus simply capturing it, since a dead pathogen poses no risk if it escapes from a filter. Independent testing to that effect has been performed by RTI International, Aircuity and the US Army.

Maintenance requirements of such systems are low, too. The lamps used to power the ROS generation process are changed every 12,000 hours. Systems such as this are installed in federal buildings and military installations in the US where the threat of chemical and germ attacks exist. That said, the costs are not prohibitive (generally from $1.25-$2 per CFM installed). So, while the potential sounds fantastic, the systems could easily become commonplace in public buildings such as hospitals.

For more, visit https://genesisair.com/ Ben would like to thank the Sacramento Governor for his leadership during the Covid-19 crisis.

IMAGE: ISTOCK

The following example uses the process of photocatalytic oxidation taking place within the air handler itself to destroy or damage viruses in the unit’s airstream. The Genesis system can destroy Covid-19 viruses found in droplet nuclei by creating free radicals in the form of a reactive oxygen species (ROS) called hydroxyl radicals (OH). Viruses are broken down as they pass through the OH field generated within the Genesis panels.

The panels are scalable and simple to install, and are most commonly installed in air handlers and as in-room units. Importantly, the Genesis system is safe to use for occupied spaces. The hydroxyl radical ROS has a half-life of 1x10-10 seconds. Therefore, it remains within the Genesis panel and does not migrate to the occupied space. Free radicals (oxidants) can cause damage to – or destroy – a body’s cells when they overwhelm the body’s natural free radical defence of antioxidants. The oxidative process is not limited to a specific organism and does not discriminate between viruses and lung tissue. So where the oxidation reaction takes place is important, and in a Genesis system, all oxidation occurs safely within the panels.

The OH ROS is not pathogen-specific, although the single-pass efficiency through the panel may vary by pathogen type. The hydroxyls in the Genesis panel are a continuously generated, controlled, exogenous source of free radicals. All the destruction happens using OH, and the reaction occurs only within the panel itself. Bio-aerosols consisting of airborne droplet nuclei (<5μm) can be carried to a return air intake and back to an air handler where they can be redistributed to other parts of a building. A Genesis

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Science of the future?

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Genesis

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s a building environmental system consultant, I am concerned with studying the emerging conditions of health and welfare in the micro and macro environment. A significant element of this is the air quality – be it the home, work, school or in public buildings. With the Coronavirus weighing heavy on everyone’s psyche, it’s an appropriate time to consider the capabilities of ventilation systems.

In a hospital environment, for example, the ventilation system is critical to reduce the contaminants within the spaces for the safety of the patients and the staff. Contaminants can be anything from the outcome of rushed maintenance, repairs, inadequate air circulation and medical procedures. In a situation such as Coronavirus it is advisable to put in extra effort to monitor the performance of the system.

However, as the latest position document on infectious aerosols from the American Society of Heating, Refrigerating & Air Conditioning Engineers (ASHRAE) states: “Infectious aerosols can pose an exposure risk, regardless of whether a disease is classically defined as an airborne infectious disease.”

Since HVAC systems can potentially redistribute infectious aerosols, strategies for treating this possible path of infection should be a primary consideration for building designers. One method of disinfecting a building’s ventilation airstream is to disinfect the air that passes through a facility’s air handlers.

VENTILATION SYSTEMS

Ben Venktash, independent Building Environment Services Engineer in the US, discusses the fantastic possibilities of state-of-the-art ventilation systems

18/05/2020 16:09

INSIGHT

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iscussions surrounding sustainability generally focus on the reduction of carbon emissions, the responsible sourcing of materials together with the recycling and elimination of waste, which are all vitally important. But sustainability is about much more than the environment. Moving away from established practice requires people with new skills, understanding and attitudes.

Education is a critical element in ensuring those entering the built environment are able to support the shift towards more sustainable systems and technology.

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Evolving definitions

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In 1987, the Brundtland Report for the United Nations said that for something to be sustainable it must: “meet the needs of the present without compromising the ability of future generations to meet their own needs”. Under this definition, sustainability can be said to encompass the social, economic and environmental needs of both present and future generations. It is this holistic definition of sustainability that is increasingly being applied to the construction industry in place of the nebulous and increasingly meaningless term green.

It is certainly the case that sustainability represents one of UK construction industry’s most important and challenging issues. In the policy paper Construction 2025: strategy, the government made it clear that it wants the UK construction industry to be a market leader in both efficiency and sustainable construction.

Its vision is for UK construction to be so efficient and technologically advanced that it can lead the world in low-carbon construction. Key to realising this, the government says construction must invest in smart off-site manufacture and digital design and technology.

In this context modern methods of construction (MMC) – off-site manufacture, modular construction or good old pre-fabrication – stand up well against the people, profit and planet triple bottom line definition of sustainability, with many attributes that make off-site manufacture of buildings more environmentally friendly and productive.

These include: Economic benefits such as faster construction and improved quality leading to reduced snagging and defects; there is also less dependency on the weather Social benefits such as improved health and safety of the workforce, improved working conditions and the opportunity

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Hand in hand Do we really understand all aspects of sustainability and how is academia strengthening this emerging sector?

Asks Andrew Pearson

to locate a factory in an area with a skilled workforce or for job creation Environmental benefits including reduced waste, reduced road traffic movements from fewer site deliveries, improved operational performance because elements are likely to be produced in accordance with the specification and design intent, and because factories can control the emissions that result from construction more effectively than construction sites.

As architect and TV presenter George Clarke notes: “It’s amazing how much more efficient and better for the environment building off-site can be, yet in the UK less than 5% of construction uses off-site techniques, compared with around 9% in Germany, 12-15% in Japan and 20% in Sweden.” He also notes that off-site building can bring the cost of construction down, offer 30% quicker build time, and is one of the ways the industry can get to net-zero carbon emissions. “So it’s a crucially important area where we really need to be making change.”

Modernise or die The need to invest in MMC to ensure the industry’s long-term sustainability was a message echoed in 2017 by Mark Farmer in his review of the UK Construction Labour Model, Modernise or Die. This highlighted the impact on the housing industry, in particular, of an ageing workforce and a reliance on on-site labour. The report said the case for change was compelling

“Education providers are struggling to recruit off-site experts to teach the next generation of structural engineers”

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EDUCATION

in the uk less than

5% of construction uses off-site techniques, compared with around

9% in Germany

12-15% in Japan and

20% in Sweden JUNE 2020

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and called for modernisation through better productivity and harnessing technology to improve long-term margins, decrease unit delivery costs and create greater predictability by de-risking on-site delivery. The document’s 10 key recommendations included a call for government to: “Encourage the use of off-site construction to improve efficiency and reduce the need for labour on site.”

Andy Goodwin, Managing Director of off-site design and build specialist

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B&K Structures, echoes Mark Farmer in saying said that one of the major issues facing the industry today is “an ageing workforce and the looming impact of Brexit”, and that the off-site industry has been, “hailed as the solution”.

Goodwin highlights the challenge of attracting, the brightest and best to structural timber technology in the UK and questions whether it is because “education providers are struggling to recruit off-site industry experts to

teach the next generation of structural engineers?” To help resolve this issue, B&K Structures has formed partnerships with Nottingham Trent University and Derby College with the manufacturer’s staff giving guest lectures to engage directly with students.

A more radical solution proposed by Goodwin is for contractor-led training programmes to form part of the planning obligation for contractors working on education projects. “We are familiar with

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INSIGHT

JUNE 2020

Sustainability is embedded into the Cardiff Metropolitan University’s design and built environment courses

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Section 106 Agreements ... these are often referred to as developer contributions ...putting back something into the community where the project is being delivered,” he says. He suggests guest lectures and contractor-led training programmes could form part of 106 Agreements for education builds. “By sharing our expertise, we will get the best opportunity to engage directly with students to promote the diverse range of career options available within the structural timber sector,” he adds.

University and industry Cardiff Metropolitan University is already engaging directly with industry on sustainability issues through its involvement with industry-based research projects that feed into its BSc (Hons) Architectural Design and Technology degree, its BA (Hons) in Architecture and its BA (Hons) in Interior Design courses.

“We try, where possible, to work with industry because it makes the teaching more relevant for the students when they work on live projects,” says Dr John Littlewood, Senior Lecturer and Head of the sustainable and resilient built environment group (SuRBe) at Cardiff School of Art and Design.

One such initiative outlined is a three-year innovation project with JG Hale Construction/Seven Oaks Modular, a South West Wales-based building contractor and on-site manufacturer of timber-frame prefabricated and modular components.

Here the university is working with the manufacturer to increase the thermal performance of their products, including the use of more natural materials for insulation, and to improve their processes to reduce costs (funded by Innovate UK and the Welsh Government).

“These types of research projects lead to examples and case studies that we incorporate into our teaching at

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undergraduate and at post-graduate level,” Littlewood explains.

Another project is Home Grown Homes.

This a project led by Wood Knowledge Wales, a body established to promote the use of locally sourced Welsh timber for structural use and in the manufacture of cladding, windows, doors and even for insulation. For this project, the university is involved in a package of assessing building performance related to timberbased projects across Wales.

The university’s involvement with manufacturers generally results from a business approaching academia with an issue that it needs help in resolving. “The problems tend to be around sustainability and/or building performance because that is what the SuRBe group’s expertise is in, and those projects then feed into our teaching.” Once approached, the university can use its connections to source other funding streams and to engage with potential project partners.

“Generally, research and innovation projects are funded in part by industry and then we will help source other types of funding to go alongside that,” he adds.

It exemplifies how academia is helping to strengthen sustainability as an emerging sector in the construction industry, and it’s a reciprocal relationship.

Each time an organisation approaches a university with an issue that needs resolving, the research and innovation involved provides an opportunity for students to get hands-on experience in industry and alerts manufacturers to the potential of sustainable applications.

It also helps improve and promote sustainable construction practices in the wider industry.

Alongside its usance in industrial projects, sustainability is embedded into the Cardiff Metropolitan University’s art, design and built environment courses.

Within Cardiff School of Art and Design, sustainability is part of theory teaching through a module called Constellation, which is taught by 20 different members of staff. “I’m lecturing sustainability considerations to a range of students including architectural technologists, product designers, fashion designers and ceramicists,” says Littlewood.

At the University of Wolverhampton, however, sustainability is taught as a defined module on the degree level Construction Management course.

“When you are talking sustainability you are talking materials, process, product and technology. We look at a project and try to assess what are the most sustainable technologies, what are the most sustainable processes and which materials are the most sustainable,” says Dr Emmanuel Daniel, Senior Lecturer in Construction Management and Course Leader for the MSc in Offsite Housing Construction.

The content of the courses is agreed with the professional bodies that validate the courses, such as CABE and CIOB, which happens every five years.

“Professional bodies understand what is needed by industry,” he says. It is the social element of sustainability and how a construction project impacts the local community that holds a particular interest for him. This might include whether

MOBIE’s first MSc in Advanced Home Futures commenced at the University of Teesside in 2018

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EDUCATION

“In some respects, the industries needed to meet the UK’s climate goals remain in the early stages of development”

George Clarke founded the Ministry of Building Innovation and Education (MOBIE) in 2017 to train and inspire young people to innovate in the design and construction of homes in the UK and abroad. According to Gerry Ruffles, Head of Education at MOBIE, the charity is about trying to bring the homebuilding industry into the 21st century in order to make it efficient and sustainable. “We’re still building houses the same way today that we have for hundreds of years; it’s slow, it’s inefficient and it’s not particularly sustainable from an environmental and social point of view,” he says.

Ruffles says that while many industries have adapted to digital technologies, construction has not. “It’s wrong in this day and age that when you buy a new home you have a snagging list a mile long, whereas if you were to buy a brand new car you would not expect to be trailing backwards and forwards to the dealership with problems. It is all down to a failure of the homebuilding industry to engage with modern methods of construction and offsite manufacture, which was why MOBIE was set up,” he explains.

MOBIE has a mission to disrupt the homebuilding sector by attracting and nurturing a new cohort of designers,

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A sign of MOBIE’s intent to drive change through the industry is its launch of Offsite Ready, a programme developed to train the trainers funded by the Construction Industry Training Board. “One of the issues with off-site construction is that the technologies are changing so fast that there were concerns that a lot of academic institutions were going to be challenged to teach these

For more information on any of the courses discussed here, visit MOBIE.org.uk/courses cardiffmet.ac.uk/artanddesign wlv.ac.uk

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Education initiatives

Training the trainers

things, particularly on vocational courses,” Ruffles explains. “For the train the trainers programme, the project partners have created 10 modules looking at all aspects of off site to provide tutors with a complete set of materials including class projects and assignments,” he adds.

Perhaps universities are preaching to the converted. At the University of Wolverhampton Daniel says that the concept of sustainability and off-site is starting to become inherent in construction. “I have 10 students working on their BSc dissertations, some of which are part time and working in industry, and I think 70% of them are looking at issues around sustainability and off-site construction because it matters to them.” There’s little doubt that academia is helping support sustainability in construction, but it’s the students themselves that are leading that.

In some respects, the industries that are needed to meet the UK’s climate change goals remain in the early stages of development. This is true as much for MMC as it is for the household and commercial refit projects needed to bring the UK’s existing stock up to zero-carbon standards. But what is becoming clear is that by working together, the potential for industry and the academic sector to accelerate this development is vast, and that it’s the students themselves who are embracing the possibilities.

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a project sourced its materials locally or took on apprentices from the local community. “We’ve done some work with Highways England looking at how their supply chain is delivering social value across their projects, it’s what we call social sustainability,” he says.

Daniel also teaches on the University of Wolverhampton’s MSc course on Off-site Housing Construction. “At the master’s level, we teach the principle of sustainability through the design and construction of off-site products,” he says.

One of the contributors to the course is education and training charity MOBIE.

makers and integrators to reshape the housing industry. In short, it seeks to embrace all aspects of sustainability, and its aim is not so much to strengthen the emerging sector within construction, it is to drive it.

To do this it has created an educational pathway through developing a series of courses, from BTEC through to postgraduate, in advanced home design, manufacture and construction. Its first MSc in Advanced Home Futures at the University of Teesside commenced in 2018, but it also provides courses at the University of Wolverhampton.

Its BTEC and HNC/D courses, which are provided in association with Pearson, are available to colleges around the country Ruffles says MOBIE is currently working with CABE to produce a Level 7 postgraduate standard to enable people to do master’s degrees using the training levy. Sustainability does not feature as a specific entity in any of the courses because it is ingrained in everything MOBIE does, says Ruffles. “I don’t think anybody would teach construction technologies and techniques and BIM without incorporating sustainability now.”

Architect and TV presenter George Clarke believes off-site building is a way to get to net-zero carbon emissions

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INSIGHT

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“Opening the window to create a livable temperature leads to a non-stop soundtrack of traffic and urban noise”

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AVO GUIDANCE

Open and shut case JUNE 2020

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t’s a conundrum playing out across the country: well-insulated, air-tight residential blocks are designed with ventilation strategies that rely on opening the windows to purge heat, when the statutory acoustic assessment for its noisy, urban site stipulated that the windows should be closed. Residents are given the keys to flats built on incompatible assumptions, with a foundation of contradictory reports that were never cross-referenced – or perhaps simply ignored.

It results in complex trade-offs in comfort levels where opening the window to create a livable temperature leads to a non-stop soundtrack of traffic and urban noise that impacts sleep and mental wellbeing. Alternatively, closing the windows – and relying on ventilation systems that are often inadequate, or noisy, or both – runs the risk of uncomfortable temperatures, stuffiness and high carbon monoxide levels. If the flat is on the ground or first floor, or accessible from the street, then security has to be added to the equation.

The situation has arisen because a trio of interlinked issues – acoustics, ventilation and overheating – are

In the race to make new builds and existing buildings energy and heat efficient, acoustic, ventilation and thermal comfort practicalities may have been overlooked. As Elaine Knutt discovers, that’s about to change

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less than

regulated by a triad of disconnected authorities. To gain planning permission, developers must submit an acoustic assessment demonstrating that dwellings will not have excessive internal noise levels, but this can be based on the assumption the windows are shut.

Meanwhile, the ventilation axis is owned by building control, and there is no statutory requirement to do an overheating assessment to predict thermal comfort.

“The acoustic report is assessed by the planners, who delegate it to the environmental health team, the ventilation strategy may not be determined at planning stage and is regulated by building control, and thermal comfort may be considered by different consultants. No one is joining the dots, so no one’s joining them together,” says Jack Harvie-Clark, immediate Past-Chair of the Association of Noise Consultants (ANC) and Director of Apex Acoustics.

To help resolve the conundrum, the ANC has produced new guidance to promote a balance between acoustic comfort and thermal comfort, and to give the different technical specialisms a common language and metrics. If a decade’s worth of residential development has been built with problems, the ANC hopes that better conversations – guided by fixed, quantitative values on noise and ventilation levels – can ensure that the next decade offers a more intelligent response.

3mto/m5/ 3

hour air tightness can have an impact on health

Arrested development Failure to balance acoustic and other environmental requirements effectively starts with disconnects in the development process. When a proposal is submitted for planning approval, acoustic assessments estimating internal noise levels must be submitted to the planners, with an EHO making a recommendation to the planning team who in turn make a recommendation to the committee. A project may be granted permission with conditions attached on mitigating internal noise, but these are never backed by post-completion acoustic checks, leaving

Trinity of factors Dan Saunders, Director at acoustic consultants Clarke Saunders, and Chair of the ANC, says: “The Acoustics, Ventilation and Overheating [AVO] Guide gives a holistic view of internal acoustic conditions and thermal comfort. It gives environmental health officers [EHOs] a reference to ask applicants or developers, ‘Has this proposal taken account of this guidance?’ and ‘What are the expectations on indoor air quality, or indoor acoustic comfort?’. And it should also help to educate people in the design team to realise that we need the acoustics advice early, not once the layout has been frozen.”

The guide was launched in January, with only a few weeks to gain traction before the Covid-19 pandemic froze projects in their tracks. Jo Miller, Director of independent acoustic and air quality consultancy Miller Goodall, says that the guidance is already proving useful. “We have directed ventilation engineers [to the guidance] to give them a better understanding of the issues between noise, ventilation and overheating. For local authority environmental health and planning departments, it will help them understand how the three areas interlink.”

Dr Anthony Chilton, Chair of the ANC working group that produced the guide, and a Head of Acoustics at building services consultant Max Fordham, agrees: “People are already being paid to do assessments using the guide, to see, for instance, if you can reduce the need for mechanical cooling.

Whether it has changed the design of a building yet is harder to assess.”

The guide covers new-build residential projects, where sustainability and practicality tend to favour sites next to noise-producing rail lines and traffic arteries.

For reasons of cost, the problem mainly manifests in

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social housing, or the affordable element of mixed tenure schemes, although consultants also describe problems in student accommodation and care homes.

However, the guide doesn’t cover retrofit programmes, which has seen plenty of problematic examples of improving insulation and airtightness at the expense of reduced ventilation and greater noise risk.

But the number of homes likely to find themselves at the centre of the Venn diagram of overlapping vulnerabilities is only likely to increase, as energy efficiency regulation tightens insulation standards and airtightness. “More and more we are seeing that overheating is an issue. Buildings have more insulation for good levels of energy efficiency, and we’re having hotter summers,” says Carolina Caneva, a sustainability specialist and Associate in the Development Consultancy Team at PRP Architects. “At the same time, a lot of clients want to be climate proof.”

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INSIGHT

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AVO GUIDANCE

However, the input data will look very different if the acoustic strategy recommendations on the acceptability of opening the windows are factored in.

Apex Acoustics has undertaken its own research into the issue, Harvie-Clark explains. “We went through 160 planning applications for major developments in London and found that of those that had both noise and overheating assessments, 85% assumed that the windows were open for the overheating assessment and closed in the noise assessment – even where the two assessments were done by the same company.

“You could say the industry standard has been to make incompatible assumptions. But in fairness, there was previously no guidance on how to assess noise conditions where you are relying on opening windows to deal with overheating.”

Process and inertia At Max Fordham, Chilton agrees that the problem may not be lack of awareness, but awareness failing to trigger action. The consultancy was hired to undertake a post-occupancy review of a large, 1,000-dwelling, social housing development in London built five years ago on a busy road. The review was prompted by resident complaints of overheating, although Chilton says it was just as much an acoustic problem – and one that had been accurately foreseen.

“We managed to get hold of the original acoustician’s report, which said that internal noise levels would be high when windows are open,” he says. “It wasn’t that people weren’t aware. Either there was confusion, with overheating and acoustics regarded as separate issues: you can’t assume that two teams will talk to one another, or that one will pick up statements in the other’s reports. Alternatively, the problem was recognised, but it would have cost money to resolve and so nothing happened.”

Chilton notes that the lack of a regulatory requirement to assess noise levels for the overheating situation leaves cost-conscious developers an open invitation. “Measures to improve summertime noise levels are often discounted on the basis of cost because they are not mandatory.”

However, Harvie-Clark believes that, with growing awareness of the problem, commercial pressures are starting to apply, as owners and developers realise that buildings harmful to health can harm their own commercial health. “People are being sued for delivering buildings that aren’t fit to live in; there is legal action going on, although everyone wants to settle cases out of court. Litigation is happening and developers are increasingly concerned about overheating risks.”

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“Failure to balance acoustic and other environmental requirements effectively starts with disconnects in the development process”

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an unclosed loop large enough to drive a deficient design through.

Meanwhile, that process is entirely separate from the ventilation strategy approvals needed to achieve compliance with Approved Document F, which is assessed by the building control team. The result is a situation where incompatible solutions can be developed. And while it’s easy to imagine that qualified and experienced services consultants are responsible for the ventilation design, Harvie-Clark says that, in the real world, it is common that no one takes responsibility for the ventilation design.

Decisions on the size and placement of vents or the power of fans are often delegated to the subcontractor, working to a few notes on drawing that they should “comply with Building Regulations”.

As a result, compliance with Approved Document F is patchy at best, non-existent at worst. Harvie-Clark summarises the results of a government study by consultancy Aecom, published last September. “The government did research on whether the Part F of Building Regulations gives you good air quality. But they found so few homes that actually comply with the Regulations, they can’t tell if the provisions are effective! Almost none complied because there were not enough trickle vents, or the air flow through fans didn’t meet the minimum requirements.” The result can be fewer air changes than targeted in the design, with Harvie-Clark quoting research that suggests health can be impacted from poor indoor air quality, particularly when the air tightness is less than 3-5m3/m2/hour.

Finally, overheating assessments are not a statutory requirement in the planning system except in London, where CIBSE Technical Memorandum 59 has been adopted into the London Plan. Thermal models calculate the risk of overheating, in terms of annualised hours that exceed maximum and minimum temperatures, by inputting data on materials, U-values, air-tightness and solar gain.

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But James Butcher, Head of Policy and Research at the National Federation of Builders, says that neither voluntary guidance nor commercial pressure alone will be enough to drive change, particularly in the social housing sector. “We’ve had too much consideration of energy efficiency, without equal consideration of other factors that affect wellbeing, such as ventilation and noise levels. If you’re relying on purge ventilation but the windows open onto a busy highway, that hasn’t really been thought about. We now have a decade’s worth of work that has caused unintended consequences. We need a long-term renovation strategy as part of the industry’s post-Covid-19 recovery plan.”

He adds: “One of the key issues with all forms of guidance is that the people who are already interested in quality and achieving high standards are likely to see it, whereas most of the problems are created by the people working to minimum standards or a low level of quality. We need a more widespread approach – the guide is probably unlikely to change things on its own.

Chilton agrees that voluntary guidance may not be enough to shift entrenched approaches cemented by financial disincentives. “Certain things have to be driven by regulation, for instance thermal insulation.

In the absence of clear Building Regulations requirements, developers would be unlikely to achieve the current thermal insulation standards given the long pay-back period. This issue is the same – there is no market incentive, so it will require a regulatory push to move the industry towards providing better environmental conditions for occupants.”

Window vents can help to achieve the balance between acoustic comfort and thermal comfort

advises a contextual approach rather than setting strict decibel limits. ProPG has now been listed on the government’s planning practice guidance website, in effect forming part of government planning policy on good acoustic design.

However, the ANC saw a need to go further than ProPG’s advice to design holistically. “ProPG tells you what you should consider, but provides no guidance on how to do it,” says Harvie-Clark. “We tried to write the AVO Guide in a way that people who don’t understand the full detail can say ‘please do a noise assessment in accordance with the AVO Guide’ and it gives you a checklist of information you should ask for as part of the planning strategy.”

For consistency and clarity, both the ProPG and the AVO Guide draw on the same definitions and levels for desirable internal noise levels for different rooms contained in two other common source documents: World Health Organisation Guidelines for Community Noise and BS 8233, Guidance on sound insulation and noise reduction for buildings. As Saunders explains: “They include the same values, the same references.

Essentially, acoustics hasn’t changed, or the criteria against which we validate a design for the average demographic.”

By linking expected noise levels, including ambient noise from ventilation systems themselves, to the four ventilation methodologies set out in Approved Document F, the guide allows design teams to adopt an integrated approach to ventilation and acoustic strategies, and recognise issues at an early stage.

(System 1, 2, 3 and 4 are, respectively, background ventilators and intermittent extract fans; natural ventilation; continuous mechanical extract; and

Regulations vs guidance Local authorities used to apply centralised planning policy on noise levels contained in the government’s Planning Policy Guidance (PPG) Notes 24, but PPGs were abolished as part of the reforms that created the and National Planning Policy Framework in 2012. This move coincided with a decade of austerity measures that saw environmental health and planning teams shrink to skeleton operations without breadth or depth of experience.

In response to the removal of PPG 24, the Institute of Acoustics and Chartered Institute of Environmental Health collaborated on developing guidance to advise local authorities and practitioners on how to chart a course through the subject’s technical and legal issues, bearing in mind that EHOs also have to consider a cross section of issues across housing, public health and safety and food safety. “People in acoustics said, ‘if there is no government guidance, we’ll write it ourselves’,” recalls Harvie-Clarke.

Saunders explains that Professional Practice Guidance (ProPG) Planning & Noise – New Residential Development (May 2017) draws on PPG 24 in classifying sites into risk categories according to the impact of predicted noise levels: where no mitigatory action is needed; where mitigation measures are needed to minimise risks; where sites should be avoided due to a significant adverse effect; or an unacceptable effect means that development should be prohibited. However, he stresses that ProPG

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AVO GUIDANCE

mechanical supply with extract and heat recovery).

A preference for windows to be openable, giving residents a degree of control over their environment, is also implicit in the guide.

The guide’s specificity should help with adoption, says Harvie-Clark. “Developers tend to push until design teams say they can’t go any further. The ProPG has no limits to it, there are no absolute values. But we all work to thresholds, we all need numbers to work to. The guide has real numbers with hard lines – a red zone and a green zone with a flexible bit in the middle.”

The problem has a regional dimension, with major urban centres such as London and Birmingham more likely to generate issues than smaller cities,

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45 BUILDING ENGINEER

Electric vehicles (EVs) are likely to become one of the themes of the decade, with the government committed to banning sales of new petrol, diesel or hybrid cars by 2035 to ensure that minimal numbers are on the road by the legally-binding 2050 net-zero carbon deadline.

With EVs emitting far less noise, doesn’t this policy shift one of the key parameters of the problem, and therefore, the design solutions adopted to mitigate it?

In fact, acoustic specialists argue that the shift to EVs will make less of a difference than we assume. Harvie-Clarke notes that approximately half of vehicle noise is tyre noise. “In acoustic terms that’s 3dB, so it represents a relatively small reduction in noise. With faster-running vehicles, a greater proportion of the noise is from tyres than engines, whereas with slower-running vehicles there’s a greater proportion of noise from engines.” The AVO Guide is written around noise levels per se, rather than assuming specific sources.

Chilton makes a similar point. “Often developers say, ‘it will all be EVs’. Yes, that would be fine except that at speeds below around 20mph, it’s tyre noise that is the main factor, not engine noise, so reducing the amount of traffic is the bigger issue – and waiting until 2035 doesn’t seem like a good policy. Cars aren’t the only mechanism for producing noise, there are also HGVs and LGVs, and people in an urban environment make a lot of noise. We can’t say that’s the solution, although long term, it is possibly a partial solution.”

But Miller points to the calm that has descended during the Covid 19 lockdown, when traffic levels fell to 35 to 45% of normal levels. When economic activity ramps up again, it’s entirely possible that there will be a shift to cycling and a collective decision to drive less, take fewer buses or stagger travel times, she suggests. “There’s also been an improvement in air quality levels, so let’s hope some positive outcomes arise from this awful situation.”

JUNE 2020

IMAGES: TEK, ALAMY

Traffic noise

where the urban heat island effect is weaker and the scale of noise-generating activities is lower.

From her north-west practice, Miller notes that the issues of overheating in the north west haven’t been as significant as you might find in London. Chilton adds that residential schemes outside the south east and major cities tend to benefit from a slightly cooler climate and better scope for cross-ventilation.

However, there is also a patchwork of regionalised responses. “Some local authorities treat balconies differently, for instance – this guide is trying to breed consistency,” reports Saunders.

In the capital, the London Plan adopted CIBSE Technical Memorandum 59 on predicting overheating risk. But according to Susie Diamond, a Building Services Consultant at Inkling (which produces overheating and sustainability assessments) where there are restrictions on the opening of windows the modelling often advises that mechanical cooling is the only viable option, ruling out adaptive thermal comfort solutions. “Some homes are getting comfort cooling in order to pass, which wasn’t the plan at all as the consequent heat rejection can exacerbate the local microclimate, and the expense of running the systems, put occupants at a higher risk of coolth poverty,” says Diamond. The AVO Guide should be helpful to give us something to push back on and say ‘what about this?’.”

Sometimes it’s not the local authority dictating this approach, but acoustic consultants’ over-reliance on the precautionary principle, according to Diamond.

“Where there is an acoustic report, it can just say ‘computer says no’ – it’s noisy on site so don’t open the windows. That means you are committed to mechanical ventilation often with cooling, which is quite a big deal and a very different environment for the people who live in that home. The guide is good at quantifying what the risk is, and it’s helpful for having those conversations [with acousticians].”

The Venn overlap But once the project has drawn on the input of acoustic and thermal modellers, what design options are available to hit the ventilation, acoustic and overheating sweet spot? Several consultants mention attenuated vents: floor-to-ceiling units, manufactured as part of a window assembly, that can supply acoustically attenuated ventilation. Typically, they have an outer steel casing and internal “splitters” constructed from fire-retardant acoustic insulation.

The units, with a door on the internal side that can be opened by the resident, allow air flow with less noise than if a conventional window of the same size was open. Horizontal units mounted below the glazing are an alternative configuration.

As Saunders explains: “It’s better than an open window for sound attenuation, possibly giving you an 18dB sound reduction [compared with an open window]. It’s not as good as it might need to be, but it’s not relying on mechanical means. However, it’s difficult to get people to buy into natural ventilation if the default is mechanical, and there is also a visual aspect, as they take up space on the façade.” The technology is already established elsewhere, he says.

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INSIGHT

JUNE 2020

“We want to get to the point where the overheating risk assessment and the acoustic risk assessment are on the same page”

BUILDING ENGINEER

46

“Scandinavia is good at doing acoustics and they do a lot of this kind of thing.”

Caneva adds that another passive attenuated option is a plenum window system, a double-glazing unit with a wider than normal air gap, and staggered inlet and outlet window openings to provide better sound protection, although she notes that these systems tend to be more expensive. If the site allows it, adding balconies at the design stage can make a 5dB difference to the internal noise levels, Chilton suggests, while shutters can also help.

Harvie-Clark has found little appetite so far among developers to trial novel systems, which fall outside their comfort zone. “We find that no one really wants to build passive solutions – they cost more to build, although they are better from a sustainability point of view.” But he hopes that the fear factor could be reduced by the AVO Guide. “Possibly attenuated vents aren’t popular as no one has had to think about these things previously. Where local authorities adopt the AVO Guide, developers will have to think about it and respond to the design challenges.”

Miller agrees that non-standard passive solutions can be hard sell to developers intent on maximising returns, particularly on large-scale developments such as student accommodation. However, PRP Architects’ Caneva has worked on another student project where the additional cost of the mitigation solution was absorbed. Diamond hopes that the guide will encourage people to: “Design windows cleverly, if the alternative is designing a mechanical cooling system.”

Part F and Part L With the guide now published, the challenge is to disseminate it. “We want the AVO Guide to be listed on the government’s National Planning Practice Guidance website; that will give it weight,” says Harvie-Clark, “We also think local planning authorities will be keen to adopt it, even though they are judged more on the quantity of housing they permit, rather than the quality.” He acknowledges that, “It will take a few years until local authorities start to adopt or refer to the AVO Guide in their local plans”.

Chilton also stresses the role of local authorities and the need to engage with their planning teams.

“The quickest way is if local authorities include it in supplementary planning guidance. If some local authorities say ‘this is important’ and included it in planning guidance, [using the guide] could form part of a planning assessment.”

However, Butcher at the National Federation of Builders points to the various downsides of a

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council-by-council approach, calling instead for a government-backed national strategy. “That leads to a patchwork effect, a postcode lottery on noise standards. We need a more macro-level approach to solving noise problems, and the interrelated problems of lighting and ventilation.”

The AVO Guide is attempting to address gaps in the regulatory jigsaw, however, the consultants generally expressed little confidence that changes to building regulations would fill in some of the missing pieces.

“The forthcoming update to Part F isn’t moving in the direction of addressing the question,” says Chilton, noting that it makes little reference to noise.

Diamond is concerned that the new Part L potentially takes away local authority autonomy on setting local energy efficiency standards, seeing this as a step backwards, but is hopeful that the draft version could yet be amended following a huge response to the consultation. Also, she notes that the Ministry of Housing, Communities and Local Government has yet to publish its intentions on the future regulation of overheating risk.

Caneva is more positive: “The new Part L will bring in tighter U-values and air-tightness, so more designs are likely to predict overheating and there will have to be more conversations on how to get that balance of avoiding overheating and achieving net zero.”

The AVO Guide itself will flex to accommodate the future updates, according to Harvie-Clark. “It’s all designed to sit within current government policies for both planning and noise, it doesn’t require a change of policy. When the update to Part F of the Building Regulations is published, we will just need to marginally tinker with the guide.”

Diamond also chooses to be optimistic: “There is a lot of support from the acousticians, at the launch event they asked a lot of questions, for instance about the granularity of overheating models, so it felt like conversations are happening. We want to get to the point where the overheating risk assessment and the acoustic risk assessment are on the same page, with the same assumptions, and where we can agree satisfactory solutions on both counts.”

Chilton is hopeful the guide will raise awareness of the need for acousticians to provide the results of reports to thermal modellers. “In the real world, studies tend to run in parallel and there’s a tendency to appoint as late as possible without much time to co-ordinate. In cases where there is only an overheating consultant, they can read the guide and see that the building could be in a high-risk category, which could trigger appointing an acoustician.”

Saunders hopes that acoustics will become a more visible issue in the early stages of project planning – joking that acoustic consultants should now be appointed directly after the Aardvark consultant.

Where sustainability and climate change are pushing design and build practices into the spotlight, it’s important to stop seeing energy efficiency, thermal comfort, acoustics and ventilation as separate entities and start to see where they overlay.

Read the Acoustics Ventilation and Overheating (AVO) Residential Design Guide at bit.ly/AVOguide

18/05/2020 15:22

COMMUNITY

CABE BENEVOLENT FUND

Letter from the Benevolent Fund Chair

S

ince the launch of the CABE Benevolent Fund, COVID-19 Emergency Grant in April we are pleased to report that we have already been able to help members throughout the world. A one-off payment has been sent to successful applicants and in most cases, we have been able to process the payments within a few days.

Lockdown restrictions may be easing for some, but the new normal that is emerging brings its own challenges and complications. It will certainly be a long time before businesses and the economy will be functioning as before.

The COVID-19 Grant

Donations I would like to take this opportunity to thank everyone who has kindly donated to the CABE Benevolent Fund.

Your donations are making a huge difference to so many members during this difficult time, and with your kindness we can now support even more members who are struggling. If you would like to donate visit bit.ly/BEdonate Kind regards Robert Biggs BSc PPBEng C.Build E FCABE Chair of Trustees, CABE Benevolent Fund

JUNE 2020

Remember that the CABE Benevolent Fund COVID-19 Emergency Grant is there to help ease the immediate distress of members, including those currently unable to work due to having to self-isolate or through illness.

If you find yourself struggling due to the effects of COVID-19, please consider applying for the CABE Benevolent Fund Emergency Grant. The application for

this one-off payment of £500 can be found at cbuilde.com and has been developed to make it as easy as possible for you to apply.

Don’t forget, you can also apply for the regular CABE Benevolent Fund for further financial assistance and support. Both the Benevolent Fund and the COVID-19 Grant were set up by building engineers to help when times are tough. So please reach out and let us help.

47 BUILDING ENGINEER

Emergency COVID-19 Support

Have you been affected by the COVID-19 pandemic?

You may be eligible to apply for the CABE Benevolent Fund Emergency COVID-19 Support >-:@

Successful applicants will receive a one-off payment of £500.00

To find out more, visit cbuilde.com/covid19 or email emergencybenfund@cbuilde.com

47 BenevolentFund.indd 47

18/05/2020 15:22

COMMUNITY

Industry movers and shakers PEOPLE NEWS

Mental health champion

JUNE 2020

M BUILDING ENGINEER

48

anaging Director of Faithful+Gould, Jon Sealy is the newest board member of the Pagabo Foundation. The Foundation was set up in 2019 by national framework organisation Pagabo and aims to raise awareness of mental health in the construction industry (pagabo.co.uk/ pagabo-foundation).

Jon Sealy said: “The charity’s mission to remove the stigma around mental health is vital. Men in particular can often hide their emotions and feelings, which can be massively detrimental to their mental health.”

Jason Stapley, Pagabo Managing Director said: “The effect of Covid-19 is profound and adding more pressure points than ever. Many people may be worried about how the pandemic will impact their jobs and their ability to earn money, others may be worried about how to stay safe while continuing to work.

“Whether a person’s struggles with mental health are a direct cause of their job or not, we want to ensure that everyone working within the industry should have access to all the provisions and help they need.”

New President of BCIA The Building Controls Industry Association (BCIA) has announced Terry Sharp as its new President.

He takes over from Jon Belfield who has held the role for the past two years. Terry has worked in the controls industry for 35 years and is an Associate at NDA Consulting, the specialist BEMS and energy consultancy practice. His experience includes UK and European leadership roles at Johnson Controls, Sontay and Satchwell Control Systems. After rejoining the BCIA Management Committee in 2017 Terry was appointed Vice President of the BCIA in January 2019.

In memory of The University of Northampton, in association with LECS (UK), has created the Alex MacDonald Award for Lift Engineering in memory of Alex MacDonald who died in February. Having studied architecture and engineering, Alex was leading a project in the Docklands set to attract worldwide attention for its bespoke design. The annual award will be given for for an outstanding dissertation submitted by an MSc Lift Engineering student.

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MEMBER NEWS CABE IS DELIGHTED TO WELCOME THE FOLLOWING INTO MEMBERSHIP: CHARTERED FELLOWS A Al-Samarraie – Shipley R Ballam – Altrincham A Barton – Southport P Hampton – Burntwood CHARTERED BUILDING ENGINEERS G Hayes – London D Healy – Garvagh W Nayanajith – Sri Lanka E Ryan – Cork CHARTERED MEMBERS T Leishman – Manchester CM Ling – Hong Kong G Rajnathsing – Mauritius HH Shih – Hong Kong WH Wong – Hong Kong ASSOCIATES M Benest – St. Helier A Cameron – Tilney All Saints G Monaghan – Enniskillen M Pita – Gerrards Cross M Reeves – Exeter A Winn – Crawley L Woodall – Dudley GRADUATES R Carter – Dorcester MC Wai – Hong Kong ACHIEVING A HIGHER GRADE: GRADUATE L Pang – Hong Kong Want to find out if you are eligible for a higher grade? Send a CV to membership@cbuilde.com for review.

WE WELCOME BACK INTO MEMBERSHIP: CHARTERED FELLOWS J Baldesco – New Zealand T Fok – Hong Kong K Kwong – Hong Kong CHARTERED BUILDING ENGINEERS H Cheung –Hong Kong A Hughes – Cardiff K Kosza – London H Tse – Hong Kong ASSOCIATE A Brint-Smee – Cranborne GRADUATE S Anush – Woodford Green WE REGRET TO ANNOUNCE THE DEATH OF THE FOLLOWING MEMBERS: Agnes Appleby C.Build E FCABE Retd b. 1937 ad. 2018 Region: Scotland John W Clenshaw ACABE b. 1928 ad. 1965 Region: Southern Mr. Irvine J. McKee C.Build E MCABE Retd b. 1942 ad. 2000 Region: North West For membership information, contact HQ on +44 (0)1604 404121 or e-mail membership@cbuilde.com The above membership information is taken from 3 April to 3 May 2020

18/05/2020 16:10

INDUSTRY MOVERS AND SHAKERS

MEMBER FOCUS

5 minutes with...

Ben Venktash, C.Build E FCABE, is a consultant Building Services Engineer and a member of CABE’s US chapter

Q

Have you always had an interest in the construction and engineering industry?

Yes, and I was lucky that a friend of my father was a New Zealand qualified Building Services Engineer.

I consequently ended up focusing on building services engineering.

Q

Q

Did you face any challenges joining the industry?

The first two years, the challenges were more in the area of safety compliances on construction sites. But the tasks were a tremendous learning experience.

Q

Q

What inspires you in your work?

When I witness the collaboration of the multi-disciplinary engineering team

Q

What advice would you give your 20-year-old self?

Do the right thing, be a good listener and follow the rules.

Q

What challenges do you see for the industry in the US? In the case of healthcare, the lack of training is a major challenge. I would like to see three-year, full-time training focused solely on healthcare facilities engineering. It’s a specific discipline that requires the extra education.

Q

How do you think these will be overcome?

By making it possible to educate and produce technically competent healthcare facility engineers.

49 BUILDING ENGINEER

What are the current challenges of your role?

As a consultant, I have recommended that clients focus on appropriately qualified healthcare facility engineers for the benefit of the operations team.

Having real experience in the field will help in effective decision-making and safe outcomes.

come together on a project. That’s truly inspirational.

JUNE 2020

Why did you choose your specialism?

I had several discussions with my maternal uncle, a respected Radiologist and Medical Superintendent at a government hospital. He instilled in me to focus on one area and become a specialist rather than becoming a general practitioner. I decided to focus on building environmental systems because a few years after completing the engineering training I learned that my father died of lead poisoning from his employment in an auto body rebuilding shop. My uncle also suggested I move to the USA to learn

more about hazardous issues in the workplace, specifically hospitals and industrial facilities. Ventilation infection control is my area of interest.

“He suggested I move to the USA to learn more about hazardous issues in the workplace, specifically hospitals and industrial facilities.

Ventilation infection control is my area of interest”

48-49 MembersFocus.indd 49

18/05/2020 16:10

JOBS

Building Control Group Manager Be one of Southwark’s Lead technical experts Take the lead on major projects Work with world class clients & developers

Up to £75k per annum CABE, RICS, IStructE, IMechE, RIBA, IFE, CIAT, ICE or CIOB qualified, a specialist in tall and complex buildings and a key player in assessing innovative construction solutions.

JUNE 2020

Closing date: 28th June 2020.

Make a difference at a local level, apply online:

www.jobsatsouthwark.co.uk

BUILDING ENGINEER

50

Webinar Wednesday

MOBIE’s Education Pathway & Train the Trainer Modules 10 June 2020 | 1 hour CPD Presented by Gerry Ruffles, Head of Education, MOBIE This webinar will focus on: • •

MOBIE’s Education Pathway Train the Trainer Modules.

Register your Free Attendance at cbuilde.com/events #WebinarWednesdays

CABE.JUN20.050.indd 50

11/05/2020 17:42

Webinars Our latest FREE CPD webinars are available to view at cbuilde.com/webinar_page and cover a broad range of topics including:

1hr D P C FREE

The Need to be Inclusive This Webinar by Sarah Sorrell of Oakley Estates Surveying Services looks at the need to be inclusive, how to be an accessible business, designing with access in mind and covers the legislation and obligations driving this.

Engineering Council Registration with CABE Jackie Macaulay, Chief Operating Officer at CABE, details the process of applying for CEng status with the Engineering Council.

Future Home Standard This webinar, provided by Graham Wright, Legislation & Compliance Manager at Daikin UK, looks at how the UK will reach net zero CO₂ emissions by 2050, looking at what technologies we will use to heat and cool buildings and how we train professionals to make this target achievable.

The Art of Getting Paid This webinar, provided by Ruth Wilkinson, Partner at Clarkslegal LLP, discusses the importance of getting paid and summarises the right to prompt payment, how that right may be enforced and identifies some of the tools and weapons that can be utilised to encourage payment by the paying party.

Our next live webinar is on 10 June 2020.

Re35ster your free place at cbuilde.com/webinar

CABE.JUN20.051.indd 49

Getting to the Core of Mental Health This webinar, provided by Jon Burgess at Jon Burgess Wellbeing, covers underlying physical factors that influence your wellbeing.

He gives practical tips and actions that once applied can not only improve your mental wellbeing but also impact many other aspects of your health.

19/05/2020 10:18

If undelivered please return to: CABE Lutyens House Billing Brook Road Northampton NN3 8NW

Constructive Collaboration 01-02 October 2020

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