Building Strategies - February/March 2010

Building Strategies

SERVING THE CONSTRUCTION & INFRASTRUCTURE INDUSTRY February/March 2010

PM 40063056

Toronto’s Green Roof Bylaw Concrete Roads Addressable Dimming Controls Rear Ventilated Rain Screens

Building Envelope Solutions From Coast to Coast

Glazing & Curtain Walls • Architectural Metals • Roofing Service & Maintenance • Roofing Systems Art Gallery of Alberta, Edmonton

Art Gallery of Ontario, Toronto

FLYNN CANADA LTD. flynn.ca

Centennial College, Scarborough

TTC: Eglinton West Station, Toronto

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contents

Building Strategies Volume 4 Number 4 • February/March 2010 Publisher | Paul Murphy

paulm@mediaedge.ca 416.512.8186 ext. 264 Editor | John Tenpenny johnt@mediaedge.ca

Senior Graphic Designer | Annette Carlucci

annettec@mediaedge.ca

Production Manager | Rachel Selbie

rachels@mediaedge.ca

Circulation Manager | Cindy Younan Contributing Writers

Keith A. Bannon Terry Bergen John Dam Blair Davies Dr. Reed M. Ellis Pierre Hebert Kelly Henry John Kubassek Dermot McMorrow Agnes Miczynska Steven Murray Andrew Parker Sherry Sutherland

Published by

President | Kevin Brown

kevinb@mediaedge.ca

5255 Yonge St., Suite 1000 Toronto, Ontario M2N 6P4 Tel: 416.512.8186 Fax: 416.512.8344 www.mediaedge.ca

FEATURES 08 Project Profile Building Strategies takes a look at Toronto’s new green roof bylaw, the first in North America that requires and governs the construction of green roofs on all classes of new buildings.

34 Enterprising Canadians Shaping the skyline one building at a time, Vancouverbased Read Jones Christoffersen has built its reputation on providing cost-effective, client-tailored solutions.

Building Strategies is published five times a year by MediaEdge Communications Inc. Subscription Rates (Canada): 1 year $46.50, 2 years $82.60, single copy $12.

For all subscription inquiries or changes of address, please contact customerservice@mediaedge.ca or 416.512.8186 ext. 259.

Reprints: No part of this magazine may be reproduced in any form – print or electronic – without written permission from the publisher.

Requests for permission to reprint any portion of this magazine should be sent to paulm@mediaedge.ca.

Copyright 2010.

Canada Post Canadian Publications Mail Sales Product Agreement No. 40063056 ISSN 1917-8026.

INDUSTRY FOCUS

DEPARTMENTS

20

06 Publisher’s Note Green Games

24

Infrastructure Bridging the Gap Concrete Roads First-class fa_ade Building Envelope A Paradigm Shift Rear Ventilated Rain Screens

28

Interiors Bringing Down the Decibels Addressable Dimming Controls

32

Mechanical Contracting Effective energy-efficient design strategies for buildings

14 Legal File Planning for Cost Uncertainty Sponsored by Glaholt LLP 16 Environment Corner Advances in Asbestos Removal Methods Sponsored by Tri-Phase Environmental Inc. 18

Engineering Forum Energy Performance Sponsored by Manulife Financial

On the Cover: Green roofs allow vegetation to grow, but beyond that, no two green roofs are alike.

Rhodiola Pachyclados flower courtesy Therma Green Roof Garden Systems and Sedum Master Green Roof Photos courtesy Live Roof Ontario February/March 2010 5

publisher's note

Green Games

I

PLAN ON

ERIP

ELECTRICITY RETROFIT INCENTIVE PROGRAM

Are yOu mAkiNg chANges to the lighting, HVAC system, motors and overall electrical system of your commercial or industrial PLAN ON building? To save you money on Eelectricity and LECTRICITYcosts RETROFIT I NCENTIVE P ROGRAM help out the environment, plan on the eLectricity retrOfit iNceNtive PrOgrAm. It’s a program Are yOu mAkiNg chANges to the that provides incentives changes that save on lighting,forHVAC system, motors and overall electrical system of your commercial or industrial electricity. building? To save you money on electricity costs and

ERIP

I finally had a chance to put pen to paper before the men’s Olympic hockey finals for this issue of Building Strategies. After overcoming a few setbacks in the early days of the Games, Vancouver proved to be a great success and source of pride for all Canadians. These games have also been touted to be the greenest ever (and not just because of the lack of snow).

There are medals made of recycled electronics, the world’s largest hydrogen bus fleet, the LEED Platinum certified Olympic Village in Vancouver’s Southeast False Creek and the dramatic Richmond Olympic Oval, where the speed-skating events were held.

It is not only Vancouver taking the lead in GREEN building. The City of Toronto has become the first city in North America to implement a bylaw to require and govern the construction of green roofs on new development effect Feb. 1, 2010. This issue takes a detailed look at the benefits of adopting this new technology and the systems available.

We also include our annual look at the Building Envelope and highlight innovative products such as Ductal from LAFARGE. This product has expanded the boundaries of innovative, cost-efficient building design.

And finally I would like to congratulate Horizon Utilities, the Ontario Power Authority and Hamilton Health Sciences who were recently presented with a cheque for $639,138, the largest ERIP cheque ever issued in the province of Ontario (pictured below). Hamilton Health Sciences received the rebate for energy-efficient lighting, heating and cooling retrofits. These retrofits have reduced the hospital’s environmental footprint and will save over $48 million in utility costs over a 10-year period. I urge you to contact your local utility and get saving!

Enjoy, Paul Murphy Publisher

help out the environment, plan on the eLectricity retrOfit iNceNtive PrOgrAm. It’s a program that provides incentives for changes that save on electricity.

the bOttOm LiNe is eLectricAL efficieNcy gOes strAight tO yOur bOttOm LiNe. the bOttOm LiNe is eLectricAL efficieNcy gOes strAight tO yOur bOttOm LiNe.

*

*

For more information, visit our website today

www.horizonutilities.com

or email For more information, visit our website today

erip@horizonutilities.com

www.horizonutilities.com

A program offered by the Ontario Power Authority and Horizon Utilities Corporation. OM An official mark of the Ontario Power Authority. * Trademark of Horizon Holdings Inc.

or email

erip@horizonutilities.com A program offered by the Ontario Power Authority and Horizon Utilities Corporation. OM An official mark of the Ontario Power Authority. * Trademark of Horizon Holdings Inc.

6 Building Strategies

ERIP Award Presentation Lunch – L to R: Eileen Campbell (Horizon Utilities); Brian Smith (Horizon Utilities); Gerry Calce (Cadbury Canada); Murray Martin, Craig Laviolette and Lloyd Ferguson (Hamilton Health Sciences); Mayor Fred Eisenberger; Alan Olinyk (Hamilton Health Sciences); Max Cananzi (Horizon Utilities) and Brad Gallant (Horizon Utilities).

Green from the Roof Down Toronto makes green roofs the law

By Clare Tattersall

8 Building Strategies

project profile

The City of Toronto Eco-Roof Incentive Program

Green Roof Bylaw Facts Size of Building

Size of Green Roof

2,000 – 4,999 m2

20%

5,000 – 9,999 m2

30%

10,000 – 14,999 m2

40%

15,000 – 19,999 m2

50%

20,000 m2 or greater

60%

*Size of building = Gross floor area **Size of green roof = Coverage of available roof space

Canada’s largest city is one step closer to becoming among the world’s greenest. On Jan. 31, Toronto’s green roof bylaw came into effect, making the city the first in North America to enact a bylaw that requires and governs the construction of green roofs on all classes of new buildings.

“It’s (also) significant for the City because

it is an exception to the Ontario Building Code and the supremacy of it over municipal bylaws,” says Dylan Aster, technical advisor to the chief building official, City of Toronto, about the bylaw during a seminar at Construct Canada 2009.

Attended by developers, contractors, architects, building operators and property

The Eco-Roof Incentive Program is meant to complement the Green Roof Bylaw by encouraging owners of existing industrial, commercial and institutional buildings to retrofit with a green or cool roof. The performance criteria for the Eco-Roof Incentive Program are consistent with the Toronto Green Standard and the Green Roof Construction Standard contained in the Green Roof Bylaw. The program was approved by City Council on December 1, 2008 and officially launched in March of 2009 with a total budget of $2.4 million for 2009 - 2012. Owners who install a green roof can apply for $50 per square metre up to a maximum of $100,000. Cool roofs, which feature a membrane or coating that reflects the sun's rays, are eligible for $5 per square metre to a maximum of $50,000.

For more information please visit http://www.toronto.ca/livegreen/ bus_eco-roof.html

managers, among others, the educational session was hosted by a panel of experts who discussed the new policy in detail.

Adopted by city council last May, the bylaw applies to all new building permit appl ications made as of Feb. 1, for commercial, institutional and residential developments with a gross floor area of more February/March 2010 9

project profile

than 2,000 square metres. It requires up to 60 per cent green roof coverage, with the size of the green roof dependent on available roof space.

The City defines available roof space as the total roof area excluding areas designated for renewable energy, private terraces and residential outdoor activity (to a maximum of two square metres per unit).

“For a smaller building that is less than 5,000 square metres, the green roof would have to cover 20 per cent of the roof space (whereas) a green roof on a larger building that is over 20,000 square metres would have to make up 60 per cent of the available roof space,” explains Jane Welsh of the City of Toronto’s urban planning and development services department.

Exempt from the bylaw are tower roofs with a f loor plate less than 750 square metres, residential buildings less than six storeys or 20 metres in height and all industrial developments. However, come Jan. 31, 2011, all new industrial buildings will require a green roof that is equal to 10 per cent of the available roof area up to a maximum of 2,000 square metres.

growing medium. But beyond this, no two green roofs are alike.

“We’ve done them on many different kinds of buildings in Toronto and they’re never the same in size or height,” says Terry McGlade, Manager of Gardens in the Sky Division, Flynn Canada Ltd. “The t y pe of green roof installed is dependent on a nu mber of fac tors, including load restrictions and what the client wants.”

Green roofs can be categorized as intensive, semi-intensive and extensive, differentiated primarily by cost, depth of g row i n g me d iu m a nd m a i nten a nc e requirements.

Intensive green roofs have a deep growing medium, ranging in depth from one to two-feet, with a saturated weight of between 50 and 300 pounds per square foot.

Due to the deep soils, they can support a variety of plants including trees and shrubs.

They are often accessible and can be used as recreational space; however, they typically require greater investment, ongoing maintenance and an irrigation system.

By contrast, extensive green roofs have a shallow growing medium (depths of six Green Roof Systems inches or less), with a saturated weight of For the purposes of the new bylaw, a between 10 and 40 pounds per square green roof is defined as an extension of an foot. Due to the shallow soils, plant above-grade roof built on top of a building selection is more limited. Also, they are that a l lowssoprema_sopranature.pdf vegetation to grow in a 9:14:32 usually inaccessible. On the upside, these 1/25/10 AM

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10 Building Strategies

February/March 2010 11

project profile

roofs are low maintenance, require little irrigation and are less expensive than intensive sy stems since t hey a re lightweight and generally do not require reinforcement.

Semi-intensive green roofs are a hybrid between intensive and extensive. They usually have a growing medium of six to 12-inches deep, with a saturated weight of 35 to 50 pounds per square foot. A variety of grasses, shrubs and perennials can be grown on these roofs. Maintenance and irrigation requirements depend on plant selection.

“It’s important to keep in mind plants

have to be compatible,” says Kees Govers, owner of Caradoc Green Roofs Ltd. “You can’t select plants that are going to overrun others if you want them to stay there long-term.”

In addition to these classif ications, green roofs can be categorized by type of system: complete, modular and precultivated vegetation blanket or mat.

Complete systems, commonly referred to as built-in-place green roofs, are more complex and permanent than the others.

Installed directly on the rooftop, they also provide the most f lexibility in terms of t he t y pe a nd nat u re of g row ing

WORLD’S ONLY HYBRID GREEN ROOF SYSTEM

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medium, drainage, protection layers and vegetation. They vary in thickness and weight and can be insta l led w ith a v a r iet y of water proof ing membra ne types.

Modu lar systems have become increasingly popular in recent years due to their ease of installation and f lexibility.

They are essentially trays of vegetation in a growing medium that are cultivated off-site and then placed on the roof to achieve complete coverage.

A pre-cultivated vegetation blanket is a pre-grown interlock ing tile that is simply placed atop the roof. The majority of the vegetation is made up of different varieties of sedum, a succulent plant characterized by its tolerance of heat, cold and dry conditions and need for l it t le irrigation and ma intenance to survive and thrive.

“Succulents have the ability to grow under conditions that no other plant can g r o w,” s a y s G o v e r s . “ ( A n d ) w i t h succulents, you have very little or no f ire spread. Succulents will burn where a f lame hits and then won’t burn any further.”

Greening the City While Toronto’s green roof bylaw is new, the City has been encouraging green roof construction for some time. In 2006, it committed to installing green roofs on all new and existing municipal buildings, “whenever practical to do so.” At that time, city council also approved the green roof incentive pilot program (superceded by the green roof pilot program in 2007), which provided financial assistance – $10 per square metre of eligible green area up to a maximum of $20,000 – to developers who ag reed to insta l l g reen roof technology. Within one year, 16 new green roofs were constructed.

Last year, the green roof pilot program was phased out to make way for the City’s latest endeavour – the eco-roof incentive program. Designed to complement the new green roof bylaw and Toronto Green Standard (a set of performance targets and guidelines that relate to site and bu i ld i n g de si g n to promote b e t te r env ironmenta l susta inabilit y of development), the prog ram prov ides f i n a n c i a l i n c e nt i v e s t o o w n e r s o f commercial, industrial and institutional (ICI) buildings to install a green roof, cool roof or combination of the two.

Owners who install a green roof can apply for $50 per square metre up to a maximum of $100,000. Cool roofs, which feature a membrane or coating designed to ref lect the sun’s rays, are eligible for $5 per square metre to a maximum of $50,000.

Applications for the eco-roof incentive grants are accepted twice a year – spring and fall. In the first round (spring 2009), 22 applicants were awarded $500,000.

project profile

Benefits of Going Green While green roof technology has been used in Europe for decades, it is relatively new to North America. As a result, the development of a mandatory green roof b y l a w w a s m e t w it h c ont r o v e r s y, supported by the green movement, but opposed by members of the development community.

To support its case for a green roof policy, the City of Toronto commissioned a team from Ryerson Universit y to prepare a study on the potential benefits, given the local environment and climate.

The study found implementation of green roof technology on a city-wide basis would provide significant economic benefits to the City, particularly in the areas of storm water management and reducing the urban heat island effect and associated energy use for cooling. The study listed other general benef its of green roofs including improved air quality, the creation of more natural green spaces, opportunities for local food production and beautification of the city.

To obtain more information on the g r e e n r o o f b y l a w, i n c l u d i n g t h e mandatory provisions of the construction s t a n d a r d , g o t o w w w.t o r o nt o . c a / greenroofs.

For the purposes of the new bylaw, a green roof is defined as an extension of an above-grade roof built on top of a building that allows vegetation to grow in a growing medium.

We are with you every step of the way.

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February/March 2010 13

Legal file

Planning for Cost Uncertainty Keep your profit when prices soar

By Keith A. Bannon

O

Owners are typically exposed to cost uncertainties when they enter unit price or cost plus contracts, while it is commonly believed that owners and contractors share this risk by entering a fixed price contract.

However, in recent years many contractors were surprised by drastic increases in commodity prices, which signif icantly increased their costs to the point where the cost of contract performance was greater than the fixed contract price.

The scenario of contractor’s performance costs being higher than the contract price may seem extreme, but in a competitive bidding situation, where profit margins are tight, a surge in material costs can easily create this result. This picture seems even less likely when you consider that the contractor clearly accepted these foreseeable risks (i.e. an increase in steel prices) when it negotiated and entered a fixed price contract.

But it happens and, as a result of these risks being foreseeable, the courts have been reluctant to shift losses due to commodity price increases to the owner.

Backing Out of the Contract The two arguments that have been most prominently used by contractors to avoid losses resulting from increasing material costs are frustration and force majeure.

However, both arguments have had little success.

For contractors to argue frustration of a contract on the basis of a material cost increase, it is necessary to show that the change was entirely unforeseeable. This is a very diff icult argument to make c on s id e r i n g t h at c om mo d it y p r ic e f luct uat ions a re d iscussed rout inely throughout the industry and now many buyers negotiate price escalation clauses in anticipation of these f luctuations.

Moreover, the courts have recognized that the parties were very much aware of the risk of commodity price f luctuations when they entered their contract.

Construction contracts commonly include force majeure clauses. These clauses typically only allow a contractor additional time to perform the contract when faced with work disruptions such as strikes or inclement

14 Building Strategies

Both owners and contractors must come to see the benefits of further allocating this risk within a fixed price contract for the use of the price escalation clause to gain wider acceptance within the industry. weather. As a result, a force majeure clause may provide a contractor additional time to purchase materials that are in short supply but it is unlikely to allow a contractor to shift the loss from a material cost increase to the owner.

When drafting price escalation clauses, further price certainty should be obtained by identifying specif ic materials that are vulnerable to cost escalations and setting out the unit prices for such materials in the contract document. Much like drafting a contractual mechanism for identifying an Risk Management unforeseen condition or a change in the When entering a fixed price contract there contract work, the contract should set out are ways contractors can mitigate the risk of notice periods for identifying price increases, increasing material costs, including: future indicators of market price increases, and periods during the contract performance 1. Purchasing large quantities of raw when the market increases may result in a materials to preserve current pricing. contract price increase.

Unfortunately, this option is typically Drafting a well defined price escalation only available to large companies that clause is essential. Without clear-cut terms have multiple projects ongoing in the for the factors influencing contract price same area. fluctuations, owners’ fears that such a clause will result in unfounded claims for extras 2. Entering agreements with suppliers for will not be subsided and interpreting such a price commitments on critical materials, clause is more likely to result in work equipment, and supplies, specifically disruptions and litigation. targeting materials that are particularly vulnerable to price escalations.

Ultimately, by negotiating a sound price escalation clause, market price increases may 3. Negotiating a price escalation clause to be accounted for within a fixed price contract share the risk of material cost increases in the same manner that the industry has with the owner. traditionally treated other significant project intangibles, such as weather, strikes, and Price Escalation Clauses design changes. However, both owners and A well drafted price escalation clause is contractors must come to see the benefits of the best way to fairly reallocate risk. further allocating this risk within a fixed However, owners are reluctant to allow price contract for the use of the price such a clause despite the fact that these escalation clause to gain wider acceptance clauses should allow more competitive within the industry. bids, since contractors will not need to increase profit margins to account for Keith A. Bannon is a partner at Glaholt LLP, a possible increases. Contractors are equally leading construction litigation boutique firm. reluctant to accept that these clauses may Contact him at KeithBannon@glaholt.com. This result in a credit to the owner, should article was prepared with the assistance of Filip Gavanski, a student-at-law at Glaholt. there be a decrease in a material cost.

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environment corner

Advances in Asbestos Removal

By Agnes Miczynska

A

Asbestos is a name given to a group of naturally occurring f ibrous minerals.

A sbestos has been heav i ly used in commercial and industrial applications due to its unique properties of being resistant to abrasion, inert to acid and alkaline solutions, and stable at high temperatures. The building and construction industry used asbestos for strengthening cement and plastics. Also, asbestos was used for thermal insulation (vermiculite), fireproofing and sound absorption.

Asbestos is a hazardous material when it becomes friable (able to become airborne).

This is measured by its ability to crumble and reduce to powder by hand pressure, such as when it is disturbed or damaged.

When asbestos is disturbed or damaged, it releases fibers into the air. Because these fibers are small and light, they can be suspended in the air for long periods.

People who live or work near asbestosrelated operations have a high chance of inhaling asbestos fibers that have been released into the air by work activities.

Once inhaled, the small, inert asbestos f ibers can easily penetrate the body’s defenses and may cause several health effects such as asbestosis.

Sealing asbestos is one option for owners of buildings containing asbestos and is typically used when removal is not an option as a result of lack of access to the area containing asbestos. This process is quicker and, in the short term, considerably less expensive. However, owners should keep in mind the cost of an asbestos management program, which will have to be implemented if asbestos is sealed. Additional costs also include repairing the sealed area if it becomes damaged and ensuring a “permit to work� program for maintenance staff. In addition, if a building or portions of a building are going to be demolished or renovated at some point, the asbestos will have to be removed prior to such activities.

The cost of asbestos abatement depends on many factors. One important factor is the type of material to be removed. Floor tiles are usually the cheapest while spray over the

16 Building Strategies

plaster material is usually the most expensive of all abatement work. Quantity is also a large factor; big jobs cost less than small ones per square foot due to the mobilization and set-up costs that are required. Other considerations include the type of removal required, number of workers required to complete the job within a given timeframe, the personal protective equipment required to ensure the safety of all workers, time required to complete removal and access to asbestos-containing materials.

Despite the fact that asbestos removal techniques have been relatively unchanged for several years, there have been some advances in the use of new equipment to cut the costs of removing asbestos, as manual removal is very time consuming. For example, the use of a high pressure vacuum system equipped with a high efficiency particulate air (HEPA) filter has several benef its over manua l remova l. This equipment is an integrated trailer-mounted system comprised of a diesel-enginepowered vacuum, a cyclone separator and a HEPA filter. During operation, the vacuum hose is brought into the enclosure around the exposed building asbestos-containing material and the powerful vacuum shreds and cuts the material, dry wall joints compound, plaster, etc. The shredded asbestos-containing material is drawn first into the cyclone separator where it is sprayed with water as it enters the unit. The wet material begins to clump as it spins at high speed in the cyclone separator. The waste is periodically removed from the separator by activating a bypass discharge valve that releases it directly into a plastic waste

disposal bag. Collected materials may be single-, double-, bulk-bagged or barreled as mandated by governing agencies.

The unit cost of removing asbestos using this equipment versus manual removal is considerably less given the appropriate circumstances. Costs include mobilization, direct costs associated with removal, waste disposal, demobilization and personal protective equipment (PPE). The technology has fixed mobilization and demobilization costs that manual removal does not and PPE is essentially the same for both methods. The cost savings come from a reduction in manual labour (time required to complete removal) as well as a reduction in waste disposal. Because the technology is able to remove and bag contaminated material at the same time and at a faster rate, the time required to complete a job is lessened considerably. In addition, the technology is able to compact material by a much larger factor when compared to compaction by manual removal. Therefore, waste disposal costs are also considerably lower. However, there are things to consider before electing to use this method of removal. For instance, the cost of mobilizing this equipment to a site is considerably greater than mobilizing a crew. However, due to the fact that the technology is cheaper on a per square foot basis, fixed costs such as mobilization can be recouped if the area to be removed is large enough to compensate for the cost of mobilization.

Agnes Miczynska is the business development manager at Tri-Phase Environmental Inc. Contact Agnes at 905.823.7965 or Agnes@triphasegroup.com.

Engineering forum

Energy Performance

Heritage context modelling points to best payback

By John Dam and Terry Bergen

E

Engineering consultants were recently required to balance thermal performance against heritage concerns in a roof replacement and building envelope restoration project at Church of St. John the Divine in Victoria, BC. Visual or character-defining alterations were largely prohibited on the registered historic building, but there was some room to manoeuvre on the exterior roof, which had been re-clad with asphalt shingles in the 1960s.

As part of the initial condition assessment, consultants used a three-dimensional energy modelling program that can provide a full energy analysis, accounting for a building’s geographica l location, intended use, construction assemblies and HVAC system specifications. This was used to develop options for increasing the efficiency of the church’s roofing assembly.

The first step was to input the performance of the existing building envelope assemblies.

These included the heritage-designated mass masonr y wa l ls, which are 450 millimetres or 18 inches thick, and the feature windows, consisting of 3.2 mm-thick panes of glass in terra cotta frames.

Two building scenarios were then modelled: 1. The retained heritage structure with the roof clad in the original slate (effective RSI-Value of 0.52 K•m2/W); or 2. The retained heritage structure with the roof clad in the original slate but with the addition of 260mm (10.3”) of standard expanded polystyrene insulation (effective RSI-Value of 7.0 K•m2/W) Assumptions for calculations In constructing the computer model, the church was treated as open interior space, eliminating the vestibule spaces in the tower and porches as well as the internal partitions that def ined space but not necessarily interior environment. Window dimensions were also simplified by grouping typical three-conjoined assemblies together as one.

Weather data from the 2002 calendar year at Victoria International Airport was entered in to the model based on four hour increments. To simplify the modelling effort, some assumptions and simplifications were made regarding other data input.

Occupancy was set to reflect relatively

18 Building Strategies

light occupancy loads except for shorter periods of high occupancy (100+ persons) occurring during regularly scheduled services.

Heating was set to 20˚C for occupied periods and set back to 10˚C when unoccupied. Due to the age of the building, infiltration due to lack of building air-tightness was set to 1.5 Air Changes/Hour (ac/h) to conform with values found for similar structures.

Building and window shading effects were not accounted for given the church ’s location, orientation and proximity to neighbouring structures. General lighting energy for the space was assumed to be equivalent to the amount of light provided by fluorescent bulbs in an average office space with the lights following the same schedule as occupancy.

The heating system for the church was set as a hot-water radiator heating system with natural ventilation using natural gas for fuel. For the purpose of the simulation, domestic hot water usage was considered negligible, as it would not be affected by a change in roof properties.

Simulated evidence The simulations showed that the main draw on consumed energy over the year is, by a large

margin, the generation of heat. The main heat losses are attributed to the lack of air tightness, followed by losses through glazing, roofing and wall systems. The main heat gains are due to the heating of the building and solar heat gain through the windows.

The simulations also provided insight into the potential improvement derived from insulating the roof. Energy model output indicated this would deliver a seven percent annual reduction, which could not justify the cost of the roof insulation. When applied against the increase in project costs for the addition of insulation, the simple payback period was in the range of 80 years.

Looking beyond the roof, the model showed where more significant losses are occurring and where gains would be needed to create either a more comfortable space or more economically feasible investment in thermal upgrades. Given the unimpressive payback that roof insulation would yield, church officials decided to focus on other areas of the building envelope assembly that would not add significant financial stress to the construction budget – i.e. addressing energy loss from air leakage through the building envelope.

Consultants are now in early stages of preliminary design with the intention of returning the roof to its original construction of slate tile on roofing felt. Preliminary analysis and modelling indicates that reducing the rate of air leakage – perhaps by as much as 33 percent – could lower the annual energy consumption in the church by more than 15 percent. Practical measures such as improving the weatherstripping of the windows and doors could potentially yield greater energy savings at a much lower cost than insulating the roof.

Once the restoration is completed, building performance will be monitored via utility billings to determine how closely the improved efficiency of the restored church compares to the construction stage energy models.

John Dam, P.Eng., LEED AP and Terry Bergen, C.Tech., CCCA, LEED AP, are with the Reed Jones Christoffersen Ltd., the engineering consulting firm overseeing St. John the Divine the roofing and building envelope restoration. For more information, see the web site at www.rjc.ca.

By Grace Pickard, Manulife Financial

Can you afford NOT to be covered for health and disability expenses?

Most people recognize the need for home insurance, car insurance and even life insurance.

x-rays, cleaning, fillings, crowns, root canals and even dentures.

If you are self-employed, your premiums for extended health care plans may be tax deductible.2

But many overlook the need for two types of insurance, the absence of which could strike at the heart of your finances especially if you’re self-employed or don’t have adequate coverage at work.

Extended health insurance. About half of all Canadians do not have extended health insurance through their employers, so must pay out of their own pocket, or hope their provincial health plan covers it.

In fact, Canadians are spending more out of their own pocket on health care than they were two decades ago — $452 per person in 2007 compared with $222 in 1981. Much of the increase was due to the rising costs of health care not covered by provincial insurance, and the fact that fewer costs are being covered.1 It has never been more important to have an extended health care plan that covers what your provincial health insurance doesn’t: prescriptions, diagnostic services, chiropractors, physiotherapists, semi-private or private hospital rooms, out-of-Canada emergency medical care, ambulances and more. Dental coverage can help cover the cost of examinations,

Disability insurance. It is far more likely that you will become disabled before age 65 than die. In fact, disability strikes working people far more often than premature death.

If a disability lasts 90 days, it is likely to last three years or more for a 35-year-old man or woman, and four years or more for a 45-year-old man or woman.3 How is a person with dependants supposed to survive without any source of income? Where will the money come from if you’re unable to work?

Disability insurance provides a source of income if you should become ill or injured and can’t work. These plans provide monthly benefit payments, based on a percentage of your monthly earnings, while you are disabled and unable to perform your occupation.

only portable: some also provide coverage between jobs so you can continue to receive benefits if you become disabled within 12 months of your last employment ending.

Look for a disability plan that offers coverage for different types of disability, such as total disability, residual disability, partial disability and catastrophic loss.

And remember that as long as you pay your own premiums (not your employer or partnership), your monthly disability benefits are tax free.2 Being ill or injured can be challenging enough without worrying about being driven into serious debt. With the financial safety net provided by private health and disability insurance, you can focus on your recovery, not on the bills. ■ 1GPI Atlantic, Economic Security in Nova Scotia and Canada,

July 2008.

2Contact Canada Revenue Agency for details.

3Disability Insurance: Where Will the Money Come From If

You’re Disabled? Canadian Life and Health Insurance Association. January 2004.

While many employers offer disability coverage, keep in mind that you can’t take your company plan with you if you leave your job. A private disability plan is not

Engineers Canada-sponsored plans: Your financial safety net Extended Health Care Plan & Dental Care Plan

Disability Income Replacement Plan

These plans help reduce your out-of-pocket medical costs by paying for those expenses not covered by your provincial health plan.

Affordable coverage for you and your family.

Provides you with a generous monthly benefit to replace lost income if a serious illness or accident keeps you from making a living — so you can continue to provide for your family.

Visit

www.manulife.com /EB to get more plan details, calculate your monthly benefits, get no-obligation quotes and apply online.

Or call toll-free 1

877 598-2273 Monday to Friday, 8 a.m. to 8 p.m. ET

Sponsored by:

Underwritten by:

The Manufacturers Life Insurance Company

Engineers Canada plans are underwritten by The Manufacturers Life Insurance Company (Manulife Financial).

Bridging the Gap

By Dr. Reed M. Ellis

T

T h e ‘g r e e n i n g ’ of t h e d e s i g n a n d construction industries continues. In a relatively shor t period of time, sustainabilit y in building design and construction has evolved from something that was new and innovative to become standa rd if not commonplace. In transportation, the industry is heading in the same direction through various green roads initiatives in North America and around the world.

Sustainable practices will be a major component of transportation design and construction, affecting every business in

20 Building Strategies

the supply chain from material suppliers to design consultants, public agencies and contractors. Taking examples from other industries, the ‘green’ inf luence will be much more than peripheral and affect all aspects of the decision-making process. For this reason, it is good business to be aware of the inf luences and plan for change.

While the building industry adopted green practices and standards gradually (due to the efforts of a few eclectic visionaries), it seems the transportation industry has jumped in with both feet.

This is a resu lt of increased public expectations, the fact many roadways are generally constructed with public funds and the industry has for a long time embraced elements of sustainabilit y, such as public transportation, bicycle and multi-use facilities and pavement management practices, among others.

So, it is really a case of turning it up a notch (or many notches in this case).

To be clear, the discussion is not so much a debate of the merits of different modes of transportation. That subject will continue to be important to both

Infrastructure

public and private industry. Rather, the discussion is about one of the safest and most eff icient modes of commercial and pr i v ate t r a n s p or t at ion – ro a d w ay s .

Therefore, the question is: How does industry do a better job of considering a holistic view of the materials used and de si g n s s e le c te d w h i le t a k i n g i nto ac cou nt ener g y u s e , env i ron ment a l impac t a nd preser v ing biod iversit y, societal and quality of life issues?

There has been progress in this area.

For example, take North America, which has seen the development of green roads

initiatives in the U.S. and, most recently, Canada. As it did with buildings, the industr y began w ith developing g u id e l i ne s for su st a i nabi l it y a nd a performance measure for roadway design and construction. Importantly, it includes ne w a s w e l l a s r e c on s t r u c t e d a nd rehabilitated roadways.

In the g uides developed thus fa r, bridges are included though only in passing. There are legitimate reasons for this apparent slight. Bridges make up a relatively small total of the built-up roadway infrastructure and as a start it m a k e s s e n s e to c on s id e r t he r o a d components first since they are comprised of fewer pieces and material types than b r i d g e s . A d d i t i o n a l l y, t h e s a m e sustainability principles that will guide highway route selection and design can be applied to bridge crossings. However, in the end it will likely be left to the bridge industry to join the green roads efforts and participate in the development of susta inabi l it y recommendations that apply specifically to bridges. This will help provide guidelines in the specif ication of materials and selection of bridge designs that are sustainable.

There are some real benefits that could result from this effort, so instead of shying away from this the industry should embrace the initiative. Hav ing sustainability guidelines and performance measures, for bridge projects will have obvious ‘green’ benefits, particularly for new design. Set ting and meeting sustainabilit y standards w ill be well supported by the bridge industry for new d e s i g n s i n c e s o m e a s p e c t s of t h e requirements, such as design considering durable materials and details, are already part of day to day design. Further, the bridge industry is constantly striving for longer service life in new designs as it specifies designs that must meet 75 to 10 0 -yea r desig n l ife. Confederat ion Bridge, the world’s longest bridge over ice-covered water linking Prince Edward Island and New Brunswick, is an example

of a structure designed to meet a 100-year design life.

There could be additional and welcome benef its in encouraging bridge rehabi l itat ion work . By adopt i ng sustainability practices and performance mea su re s it is ea s y to demonst rate repairing and rehabilitating Canada’s bridge infrastructure is more sustainable than simply building new bridges. Using a ‘sustainability index,’ needed funds for rehabilitation could likely be shown to be more sustainable than funds for new construction. This would be a welcome change for many agencies that lack the proper funding for bridge preservation and have the total support of public.

Quite simply, bridge preser vation is sustainable and this can be demonstrated by considering sustainability measures.

In addition to this is the less obvious benefit that meeting targets could lead to more aesthetic bridge designs as performance measures consider societal impact including aesthetics. Sadly, many agencies approach bridge aesthetics as a non-essential part of design, if it warrants consideration at all.

Whatever the reasons may be for the lack of emphasis on bridge aesthetics, if considered in the sustainability index then the industry might see higher standards for aesthetics and this would be an improvement in the opinion of many.

So, no matter how the industry looks at it, the sustainability movement is here to stay and will affect businesses in many ways. Embrace it or fall behind.

Dr. Reed M. Ellis is a senior principal and bridge engineer with Stantec Consulting. Among other things, Dr. Ellis specializes in the management of bridge inventories, including inspection, maintenance and rehabilitation, and life cycle cost analysis of infrastructure. Founded in 1954, Stantec provides professional consulting services in planning, engineering, architecture, interior de sign, landscape architecture, surveying, environmental sciences, project management and project economics for infrastructure and facilities projects.

February/March 2010 21

Infrastructure

Concrete Roads: The New Economics C

By Sherry Sutherland

Concrete pavements are well known for their strength, durability and long life. In the past, however, they have also been associated with a high initial price tag.

Over the years, a number of life cycle cost studies have been conducted and concrete pavements have continuously prevailed thanks to the significantly lower maintenance and rehabilitation required.

Concrete pavements are now also cost competitive on a first cost basis. The new paving reality is that comparative initial bid cost and life cycle cost assessments will increasingly favour concrete over asphalt in the foreseeable future.

Public officials across the country are faced with the increasing challenge of managing road assets on a stagnant or, in some cases, decreasing budget. It is more important than ever for government to critically evaluate paving material options and determine the best course of action when spending taxpayers’ dollars.

Making the Case for Concrete Roads The Ready Mixed Concrete Association of Ontario (RMCAO) and the Cement Association of Canada (CAC) announced Dec. 15, 2009, the launch of CANPav, (w w w.canpav.com) the online version.

Designed after extensive consultations with major road builders, CANPav is an online soft ware model ling tool that quickly determines the cost advantages of using concrete as the paving material of choice for municipal streets and roads as well as commercial parking lots.

CANPav is unique because the user has complete control over the concrete and asphalt cross sections and the material cost inputs that will be used to construct municipa l streets or the commercia l parking lot estimates.

The advantages of CANPav are many.

It quickly performs concrete paving cost comparisons, evaluates both municipal streets and roads and commercial concrete parking lots, saves cost estimates and material cost inputs online and applies cost estimates to all projects. Summaries of cost comparisons can be saved and printed. CANPav also provides online access to the StreetPave software program for concrete roads and considers the cost effects of future maintenance activities.

Once logged in, users have the ability 22 Building Strategies

to conduct numerous “what if ” scenarios comparing the initial construction costs of both concrete and asphalt paving materials and then save projects.

The tool has been created for use throughout Canada and currently includes default cost values for Ontario and Quebec. These values can be replaced so other municipalities can benefit from the tool.

Pavements and the Economy For decades it has been accepted that the initial construction costs of asphalt pavements were cheaper than concrete pavements but that is changing. Provincial and municipal government infrastructure spending will increase to address old infrastructure repair and replacement, with concrete poised to be the material of choice.

Emerging changes in refining practices will lead to a significant reduction in future liquid asphalt supply. New oil refinery processing units take the “leftover product” and further refine it into higher priced products such as diesel, fuel oil, gasoline and motor oil. This means there are

fewer products available for bitumen and its prices are increasing globally. The projected increasing costs associated with oil, asphalt and bitumen, combined with the projected shortages, mean concrete pavements will continue to be more competitive in the future.

Asphalt paving costs have increased 148 percent during the past 4.5 years and fluctuated between an increase of 45 and 113 percent during the past 20 months. Concrete has not been as severely impacted by the current state of the economy and continues to provide a stable price point.

In ‘life’ terms, concrete pavements last longer than any other type of pavement. In sustainabilit y terms, concrete pavements reduce emissions and greenhouse gases. In economical terms, concrete pavements are the best choice in initial and long-term cost.

Sherry Sutherland, MASc., P.Eng., LEED AP, is a technical engineer with the Ready Mixed Concrete Association of Ontario (RMCAO). For more information, contact Sherry at ssutherland@rmcao.org.

Infrastructure

First-class Façade

Fiber reinforced concrete panels solve design issues

By Kelly Henry

T

The 800 Yates Street project is a 204,000 sq. ft., class A commercial and retail space loc ated i n Vic tor ia’s h istor ic d o w nt o w n d i s t r i c t . C o n c e i v e d b y D’Ambrosio Architecture + Urbanism, the design uses state-of-the-art energy eff iciency and environmental control measu res w it h h igh emphasis on operational f lexibilit y as well as the comfort and health of its occupants. To do so, the design focuses on a seven storey open atrium at the center of the building.

The walls undulate in a more free form curve as compared to the straight lines of t he st reet side façade. Because t he architect sought to keep the façade the same on all parts of the building (as it curved into the atrium), this gave rise to cha l lenges t hat convent iona l façade systems had trouble solving.

A n u lt r a-h i gh p er for m a nc e f ib er rein forced conc rete ( U H PC) ca l led Ductal® was chosen for the spandrel panel section of the unitized curtain wall system. There are several reasons why this material was chosen. First; the tight radial curves into and out of the atrium would have required any f lat panel system to be cut down in order to make the turn.

This set up would have created several seams that would not only be aesthetically unattractive; it would a lso result in several more openings within the façade that could have a degrading effect on energ y ef f ic ienc y. U H PC is h igh ly moldable and well suited for precast solutions that may be formed to almost any mold. Lafarge’s precast team in Calgary was able to produce all of the panels from just three different mold types. Because of its ultra-high strength and ductile properties due to the fiber reinforcing conventional rebar reinforcing was not necessary within these panels. By eliminating the need to ma inta in a concrete covering over rebar, a tighter radius is achievable, allowing the UHPC

panel to span the entire curve, thereby eliminating gaps. In addition, by using a white U HPC premi x design, energ y eff iciencies are gained through this specific base color. The white color gives an SRI ref lectance value of .7 and an emittance value of .9, while the panels serve to ref lect heat energy from the sun that may otherwise cause a higher heating load for the entire building. With the material’s fiber reinforcement and lack of rebar, the panel design was able to be t h i n n e r a n d l i g ht e r (c o mp a r e d t o conventional concrete). The light-weight panels met t wo ver y impor tant requirements for this design. First, the overall structure of the building could be reduced as it no longer has to carry a h igher weight a nd second ; bec ause Victoria is situated in a seismic zone, the panel lightness made it possible to keep the necessary seismic components at a minimum. As well, the UHPC panels would provide superior durability, low maintenance and overall, an extended life span. The material’s matrix is extremely dense compared to traditional concrete, giving it particular qualities that are similar to natural stones, and exponentially increasing the life expectancy of the panel. Maintenance issues are greatly diminished because the surface pours will not collect environmental debris as easily

as other materials, so the need for regular cleanings is reduced.

In addition to the elimination of gaps, lightness (for seismic eff iciencies) and longer expected life span, the UHPC material allowed creation of a customized panel with a specif ied color and the architects’ own distinctive, hand-designed pattern - realized in clay and transferred to the panels through the use of a replicated form liner. Clearly, with the unique combination of superior properties and design f lexibility made possible with precast UHPC, architects around the world will soon begin to see an increase in demand for durable, ultra-thin and lightweight panelized façades.

Kelly Henry M.Arch | MBA | LEED AP®, is the Architectural Project Manager for Ductal® at Lafarge North America. For more information, contact Kelly at kelly.henry@lafarge-na.com.

Lafarge in North America is part of the Lafarge Group, a world leader in building materials that is active in 76 countries, and employs 90,000 people.

The largest diversified supplier of construction materials in the U.S. and Canada, Lafarge produces and sells cement, ready-mixed concrete, gypsum wallboard, aggregates, asphalt, and related products and services. For more information, visit www.lafargenorthamerica.com.

February/March 2010 23

Building Envelope

A Paradigm Shift

New approaches to curtain wall design and construction

By Steven Murray

T

The inf luences of sustainabilit y and integration are everywhere, evident in any discussion of technical innovations, design advances or constr uction techniques. These terms also apply to curtain wall design and construction in many ways.

Susta inabilit y applies to materia ls selection, material and energ y usage reductions and many other aspects.

Integration applies to both physica l integration of components or functionality i n ne w w ay s a s wel l a s i nteg r ate d processes of design and modelling to optimize a system at the macro level.

Daylight har vesting or daylighting refers to systems that reduce artificial light requirements in building interiors.

Daylighting is certainly not new but it has traditionally been accomplished by means of the primary structure, geometry a nd or ientat ion of a bu i ld i ng.

Fallingwater, among many of American architect Frank Lloyd Wright’s other creations, made great use of horizontal structural projections to shade portions of the façade while allowing light to ref lect from other surfaces and enter the building indirectly. Light shelves, which apply the shading and indirect lighting concept more specifically to small areas of a façade, are a common feature on modern green buildings.

Curtain walls have integrated exterior shading elements for some time but by applying a similar approach to the interior side manufacturers have created purposemade light shelf elements. These provide daylighting benef its while eliminating the need for additional str uct ure or pa r tition elements thereby reducing construction costs. Further cost-savings are possible through the use of light diffusing insulating glass (IG) units.

These IG units have f ibre optic-like elements integrated inside the air space between the glass layers, which redirect the incoming light from its original angle of incidence so that it exits largely perpendicular to the glass surface. This reduces glare and concentrated solar gain at f loor level with no additional shading

24 Building Strategies

or l ight shel f elements be yond t he specialized IG units.

The traditional passive shading design approach has been to choose the horizontal dimension of the shading element to shade the majority of a window surface from the summer sun. This creates less shading of the lower angled winter sun allowing for increased solar gain at a time when it is more desirable. Motorized adjustable shading elements are now being integrated into curtain wall systems to achieve active shading to further optimize seasonal shading and solar gain benefits.

The other approach to this smart shading involves saving energy as well as generating energy. By replacing spandrel panels, glass or other materials in vertical curtain wall or sloped glazing systems with photovoltaic laminates, the building envelope becomes part of the electrical generation grid. While this concept is clearly feasible the question is whether it can become economical. So far, paybacks have generally not been attractive without government incentives. Huge research and development investments are being made and production costs are dropping, however, the jury is still out on the future of cladding-integrated photovoltaics.

Wooden curtain walls – where the structural members are wood rather than the typical aluminum – approach the sustainability challenge from the material selection perspective. Wood is a renewable resource, has much less embodied energy than aluminum and has a lower carbon footprint. Embodied energy is a measure of the energy consumed in the acquisition of raw materia ls, their processing, manufacturing and transportation to site, construction and demolition. Presently, the embodied energ y costs are not wel l represented in the material commodity prices but this may well change if proposed carbon trading laws are enacted. The materials with higher embodied energy and carbon footprint values will inevitably have higher marketplace commodity prices, which will make alternate materials more cost competitive.

The inherent f lexibility of the modular glazing system and the pre-fabricated

unit iz ed pa nels lends itsel f wel l to integrating numerous types of components into a unitized panel. Each component or function added to a curtain wall comes with certain trade-offs such as with integrating floor surfaces into a unitized panel.

Self-supporting projections can be fabricated within unitized wall panels to create horizontal occupiable areas. These curtain wall projections may have the benefit of reducing the complexity of the primary structure and have little impact on the total embodied energy. The operating energy penalty due to the lower effective R-value of these projections will accumulate over the life of the building and can far outweigh the initial trade-off benefits. Sophisticated modelling is required to adequately capture the life cycle cost impact of such trade-offs.

building envelope

Whole building analysis or macro level modelling allows designers to assess operating energy impacts, such as heating loads, cooling loads and solar gain, from changes to envelope design, building shape or orientation.

Component level or micro modelling is critical in this process since the effective R-value of a curtain wall segment can be as little as half the nominal R-value. Unusual framing such as projections or outside corners can reduce the effective R-value even more dramatically.

These components can now be more accurately analyzed with the coming of age of 3D thermal modelling.

More importantly, however, is the Life Cycle Assessment (LCA) of the whole building on a broader environmental impact basis. The non-profit Athena Institute has developed the Impact Estimator for buildings,

an LCA software tool “that allows users to express a design in simple terms to assess the environmental implications of their choices” under categories beyond energy measures, such as air emissions and resource use. Tools like this can provide a way to compare the relative impact of different design choices, such as wood curtain walls versus aluminum curtain walls or steel structures versus concrete structures.

Designers will soon view these LCA and modelling tools as a day-to-day reality of the job. Another reality is that much of what designers envision will soon be produced in Chinese factories. Contrary to the widespread belief all Chinese production facilities are driven by cheap labour and low quality, many use a high level of technology and employ highly adaptable staff able to customize

fabrications. The capacity, speed and quality of these Chinese producers will continue to inf luence the industry in Canada in the short-term.

Adapting to the rapid ly evolv ing sustainability movement may ultimately have even more influence on the industry. To paraphrase the Chinese proverb, “We are living in interesting times.”

Steven Murray, P.Eng., PMP, is a building envelope specialist and managing partner of the Burlington office of Morrison Hershfield Ltd. Morrison Hershfield is an employee-owned North American firm with 13 offices and 700 staff focused on the collective vision to be the first call for engineering solutions that make a difference. For more information, contact Steven at smurray@morrisonhershfield.com.

February/March 2010 25

Building Envelope

Rear Ventilated Rain Screens

A new old way to improve building envelopes

By John Kubassek & Blair Davies

B

Buildings are increasingly under attack.

The solid wall portion of a building can be done differently. Increasing water damage and temperature cycling are increasing deterioration. Environmental impact is a hot topic, and durability requirement is becoming more prominent in design. Renovations of façades that were only built in the last few decades represent a booming business. Costs are impacting the quality of decisions in the long term, and products and systems are being chosen that will require premature repair. This author made a morning walk through downtown Toronto and found examples of premature deterioration of façades throughout the city. These issues and trends are making people wonder if things could be done differently.

In the last century, a Rear Ventilated Rain Screen, which pressure equalizes a nd ma na ge s w ater a nd w i nd , w a s developed. Some references refer to it being started in labs in Canada after W W I I . Ho w e v e r, Eu rop e a n s h a v e deployed the system in wider usage.

Products have been developed to provide the outer skin and substructures. These products a nd ideas a re increasingly entering designs of new and retrofitted buildings in North America.

The key characteristics of a pressure equalized Rear Ventilated Rain Screen (RVRS) façade include: • porous exterior claddings, primar y drainage plane; • cavit y behind outer sk in, t y pically 25-50 mm; • generous ventilation access at top and bottom of wall of each f loor; • rigid wall at back of cavity; • breathable weather barrier over wall, creating secondary drainage plane; • v e r t i c a l g i r t s , c r e a t i n g v e r t i c a l compartmenta lization of 60 0-10 0 0 mm wide; and • air-vapour barrier, typically on warm side of dew point, tertiary drainage plane.

26 Building Strategies

RVRS façades offer a choice to manage water in all its forms, protect insulation and improve wall performance. Other rain screens exist of course (e.g., masonry wall). These systems count on gravity for draining, and are not as aggressive in dealing with water in all its forms and are not pressure equalized.

A pressure equalized system means that pressure on both sides of the outer skin is maintained equal. In addition, there are several layers of defense: the outer skin; the weather membrane on the inside of the cavity; and an air-vapour barrier inside the dew point of the wall.

Stack effect and wind forces are always d r y i n g o ut t he w a l l s y s t e m . T h i s effectively eliminates the remaining moisture force.

These systems are chosen by architects and owners for several reasons. The exterior skin takes the abuse from the weather, absorbing and dispersing solar heat loads. Insulation is always drier.

Water is managed in all its forms in a natural way through ventilation. Thinner, lighter walls can be constructed. RVRS can be designed at lower costs than many other systems. They last longer.

RVRS façades can offer better insulation performance; therefore, heating-centric applications are best suited to these systems. They are applicable to new and renovation construction.

The outer sk in product lines have exploded with innovations in fire cement, ceramic, wood veneers, unique metals (like zinc) and other products. These offer a wide set of aesthetics to the designer at all price points. Outer skins can have different textures, patterns and shapes as well. So architects have chosen t hese k inds of sy stems for c reat ive reasons, as well as increased performance.

D e t a i l i n g i s s t r a i ght for w a rd but different from other systems. Instead of sealing the wall with caulking, open joints create natural ventilation. Open joints are easier to construct and inspect.

Systems can have visible or invisible fasteners. Substructures can be metals (like aluminum or steel), wood or other materials.

The system f lexibility is part of its attraction. One can modify widths, areas, joint locations, etc. to meet aesthetic and engineering requirements as one sees fit as long as the main components listed previously are maintained.

Buildings that have used these kinds of systems include: • Toronto Housing, 60 Richmond East, Toronto; • Ottawa and Prince George Airports; • S h e r i d a n C ol l e g e , Un i v e r s it y of Waterloo, Guelph University, University of Toronto, University of Victoria; • N i a g a r a R e g i o n a l G o v e r n m e n t building; • Markham, Belleville, Surrey YMCA; and • Many residences and small commercial buildings John and Blair lead Engineered Assemblies Inc. (EA), an innovator in RVRS façade design, product and construction. (w w w. engineeredassemblies.com).

Simplicity is an environmentally responsible lighting solution that will take you well into the future and still be leading the way.

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energy efficient Advance Optanium ballasts with anti-arcing protection and lamp auto re-strike capability. Providing you with a lighting solution that ages gracefully. www.philips.com

Skills Training & Education

E Lifestyles: Bringing E Down the Decibels

By Pierre Hebert

28 Building Strategies

Est imat ions show more t ha n 5,50 0 highrise buildings shape the skylines of Canada and an additional 20,000 more dot the landscape in 20 of the United States’ largest cities. The majority of these tall buildings have been built since 2000. And whether they are residential condominium highrises or off ices of global corporations, they are home and work space to millions of people.

It is worth considering what attracts urban dwellers to this vertical-living lifestyle. Whether residents are young professionals, parents, retirees or the ubiquitous baby boomers, they all seem to value convenience and an upscale lifestyle that allows them to avoid giving up their weekends to perform maintenance chores common to single-family home ownership.

Some of t he fac i l it ies a nd ser v ices available as part of the highrise lifestyle include concierge service, restaurants, pools and spas as well as shopping and

interiors

c u lt u ra l at t rac t ions w it h in wa l k ing distance. Living in urban areas also has a positive environmental impact – people have easier access to public transportation to and from work. When residents leave their condos for extended periods, as many young professionals do on business trips, they can have a greater feeling of secu r it y about t heir homes a nd possessions.

With all these upside benefits to the highrise lifestyle, can there be a downside?

There are a few challenges condo owners must adapt to. Storage space is much more limited, pets (especially dogs) are more difficult to exercise, parking for tenants and guests might be limited and homeowner associations may restrict renovations more rigorously than a person has been accustomed to in a single-family homes. And, of course, there is the issue of architectural acoustics.

After moisture issues, sound isolation control is the most discussed problem in multi-family dwellings.

A tena nt c a n b e a f fec te d by t he reverberations through f loors and ceilings from activities conducted by immediate neighbours. The impact noise and sound transmission noise can be magnified if the condominium f loors are tiled.

To minimize this, the solution begins with the initial floor covering installation. The architect or acoustical engineer for the highrise should specify a sound reduction membrane be applied to the concrete substrate before tile or stone is set.

Tile contractors should then look to two sound ratings as a guide in choosing the sound reduction membrane most appropr iate for the ti le or stone installation.

The first rating is Sound Transmission C l a s s (S T C ). T h e l o s s o f s o u n d transmission provided by a material is a measure of its ability to resist airborne sound transfer at the frequencies 125-4000 Hz. Analysts record the sound spectrum that passes through the material using a spectrum analyzer to derive this rating.

W h e n t e s t i n g i s p e r for m e d i n a n accredited testing laboratory, the sound reduction membrane should achieve a min imum STC rat ing of 50. Qu ite simply, the better the engineering of the membrane, the higher the rating will be and, as a result, the more airborne sound it can isolate.

The second t ype of rating used to measure sound reduction membranes is the Impact Insulation Class (IIC) rating.

Instead of the airborne sound of voices, televisions and radios, the IIC rating measures the ability to attenuate impact sounds, suc h as footsteps f rom t he neighb or up st a i r s. T he I IC te st is performed using a tapping machine that incorporates f ive steel-faced hammers

After moisture issues, sound isolation control is the most discussed problem in multi-family dwellings. that strike the test f loor and generate noise in a room below. The noise levels are measured and used to calculate the IIC. The International Building Code has adopted a minimum IIC of 50 for multifamily dwellings; however, the higher the IIC rating, the better the noise reduction.

It should be noted that STC or IIC among other things does not address low range frequencies. For this reason, it won’t block every sound.

Also, experience has shown the type of floor and ceiling assembly impacts the results, so do not hesitate to ask for a test report and look for the assembly used for the test when comparing options.

One such option is a f lexible, thin, load-bearing, fabric-reinforced, “peeland-stick ” sound reduction and crack isolation sheet membrane, which dramatically reduces the annoyance of airborne and impact sound transmitted

through f loor and ceiling assemblies. A premium 2.3 millimetre “peel-and-stick ” membrane can offer an STC rating as high as 73 and IIC rating of 69. This membrane can also serve double duty by offering in-plane crack isolation up to 10 millimetres (0.375 inches). Contractors who use these types of sound reduction membranes help turn the highrise condo buyer’s expectations of a good building into the peaceful enjoyment of a great vertical living space.

Pierre Hebert manages the technical services department for Mapei Inc. He received his degree in Pure and Applied Sciences and is a member of the American Concrete Institute, Construction Specifications Canada, International Concrete Repair Institute and the Terrazzo, Tile and Marble Association of Canada.

Pierre is also Mapei’s representative to the Canadian Green Building Council.

February/March 2010 29

Interiors

Addressable Dimming Controls

By Andrew Parker

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Why are lighting controls important for energy management?

Lighting comprises an average of 39 percent of the average commercial office building’s electrical energy consumption, which makes it the single largest energy load. It should come as a surprise then, that lighting eff iciency measures are commonly restricted to high performance f luorescent lamps and ba l lasts, convent iona l rel ay pa nels a nd w a l l switches with integrated sensors. Lighting has simply not been considered to be a “controllable” building load for electrical demand management purposes.

30 Building Strategies

Limitations of conventional lighting controls The old standard low voltage relay based panel is the most prevalent form of facility wide lighting control, turning lighting circuits on by a time schedule and sweeping off only after an entire office floor is completely vacated. Occupancy sensors have helped with great results by turning lights on only when a room is occupied, but they are used only in discrete rooms and only function locally.

While time scheduling and occupancy sensors certainly save energy, ultimately, the ability to control lighting fixtures is often restricted to their electrical circuiting. This results in an entire circuit or “zone” of lighting

turned on if a single person is occupying the space. It is not possible to provide light to the single workspace or tune it to the task being performed. The general lack of centralized “intelligence” prohibits deployment of advanced lighting energy management strategies and the integration or sharing of data with other building systems such as HVAC, shading, security and fire.

Emergence of addressable dimming controls Bringing the control point down to the individual fixture level via unique addressing of fixtures is the key to energy savings from

interiors

lighting in the 70 percent range. With lighting costs nearing the $1 per square foot per year range, this can represent significant operating cost savings. These savings have been shown to drive average fixture density below 0.4 Watts per square foot by pairing the benefits of addressable control with dimming ballasts and a centrally managed facility wide control software designed specifically for energy management. This software allows for integration with other building systems for further savings.

The central control software is key to the seamless integration of the lighting energy management strategies. User friendly floorplan based navigation allows the facility manager to change system settings and configurations from a single computer workstation, or even remotely via the Internet. In addition to the common time scheduling and occupancy sensing switching strategies, many dimming strategies may be deployed, while the lighting is in use! Dimming of fluorescent lighting is a powerful energy management strategy for two basic reasons: Our eyes readily adapt to a wide range of light levels and gradual changes are not noticeable, and in contrast with incandescent lighting technology, fluorescent lamp efficacy remains constant until light output dims described below 40 percent. Combined, these factors, with addressable dimming control and the six energy management strategies described below achieve the goal of eliminating wasted energy from lighting without sacrificing lighting quality for the user.

Time scheduling Lights can be scheduled to be turned on/off by zones as small as an office, workstation or even a light fixture.

Occupancy sensing Lights are automatically turned on or off based on occupancy detection. Zoning is independent of electrical circuiting and the software association of sensors to fixtures allows for multiple sensors, overlapping and secondary support zones to be configured.

With dimming capabilities the occupancy signal can also be configured to dim lights to save energy to reduce lamp restriking in frequently accessed areas. The sensors also report to the central controller so real time occupancy data can be made available to other building systems without secondary relays and wiring to each sensor.

Daylight harvesting Lighting fixtures also take advantage of the software association to daylight sensors to take advantage of ambient natural sunlight that is being taken advantage of in new environmental building design standards. Daylight harvesting can be selectively assigned to individual fixtures based on sunlight received, not electrical circuiting. This simplifies installation wiring, reduces control equipment costs and ultimately provides a higher degree of daylighting savings than with conventional analog controls.

Personal control Each light fixture can be dimmed or turned off individually by each occupant from their IP phone or personal computer to suit their preferences. This not only contributes to productivity, but is a significant contributor to energy savings as most users dim lights below default light levels.

Task tuning Generally, lighting is designed to meet a minimum standard for general tasks with a calculated safety factor to account for lamp lumen depreciation over time and are subsequently operated constantly at full output.

Addressable dimming provides the ability to tune back this overlighting and set default light levels to suit each individual task or space use.

The inherent flexibility allows light levels to be adjusted over time or as building usage changes.

Load shedding Demand side management programs are constantly being deployed in marketplaces with capacity limitations. The use of lighting systems in peak demand periods make addressable dimming system’s automatically executes load shedding in response to energy price spikes or to reduce peak demand. Lights are dimmed selectively by lowest priority areas first in a manner that is transparent to occupants and coordinated with other building loads.

Integration with other building systems Convergence is occurring between building systems with greater integration of lighting with HVAC, card access, security, fire, shading, etc. often using existing LAN intrastructure.

Common building automation protocols such as BACnet, LonWorks and Niagara AX allow occupancy and other data to be shared for enhanced energy and operational savings.

Green, sustainable buildings are a major market driver The market is demanding green, sustainable, intelligent buildings in part because energy costs are leading the inflation curve. Increasing time of use penalties inherently dictate we will have to reduce energy use to keep operating costs in check. LEED has emerged as the dominant building standard and tells us that lighting controls not only save energy and the atmosphere but also contribute positively to our indoor environmental quality by reducing the lighting control zone.

ASHRAE 90.1 has established lighting power limits for many applications and required the use of automated controls. In order to drive the average lighting power density down below its plateau of one Watt per square foot, the control zone must be further reduced to the individual fixture.

Is there enough value in investing in addressable dimming controls?

With energ y cost s on t he r is e a nd addressable dimming controls providing c l e a r l y s u p e r io r e n e r g y s a v i n g s a s c omp a r e d to c onv e nt ion a l l i ght i n g controls – 50 percent to 75 percent savings – payback from energy savings averages 3 to 5 years in most markets.

Utility incentives, tax deductions and other programs f ur ther improve the value proposition. LEED recognizes the energ y and product iv it y benef its of add ressable l ight ing cont rols wh ic h cont r ibute sig nif icant ly to many p r e r e q u i s it e a n d c r e d it c at e g or ie s .

Advanced load shedding capabilities and the ability to aggregate multiple building lo a d s prov id e c ont rol of e l e c t r ic a l demand which directly impacts operating costs. Providing the user the control of the lighting in their own workspace improves workplace ergonomics, satisfaction and reduces energy use. So, is there enough value in investing in add ressable d imm ing cont rols? T he question is: Can we afford not to?

Andrew Parker, PEng, LEED AP, LC, (aparker@encelium. com) is Director of Sales for the Canadian market for Encelium Technologies. He has 10 years of experience in the advanced lighting controls technology sector, has spoken at conferences and has been published on the topic of advanced lighting controls and energy management.

February/March 2010 31

Mechanical Contracting

The Green Building Agenda

Effective energy-efficient design strategies for buildings

By Dermot McMorrow

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The green building agenda is revolutionizing the construction industry in Canada, supported by a series of wellestablished energy eff iciency programs suc h a s LEED, BOM A BESt, a nd HPNC, which a re driv ing not only building design but the financial decisionmaking process. Building design and implementation teams are now focused on t he c om mon g oa l of a c h ie v i n g predetermined energy efficiency targets with associated green building status or direct financial incentives, depending on the program involved.

This new agenda is changing the industry mindset and opening the door to innovation and the application of a range of technologies now considered mainstream.

Renewable Energy Systems Renewable energ y sources such solar photovoltaic fields or low-grade energy sinks offered by geothermal fields have often been viewed as technically feasible but not always an effective return on investment (ROI) based on the significant capital cost premiums associated with such ventures.

However, technolog y is starting to change this reality. Solar photovoltaic panels are now being designed to offer ef f ic ienc ie s a s h igh a s 15 p ercent.

Geothermal heat pump systems are now able to achieve full heating capacity levels at entering f luid temperatures of 32˚F. The anticipated future cost of energy, potentia l impact of ca rbon trad ing, coupled with recent government and utilit y-driven geotherma l or district energ y geared incentive programs, is fostering the willingness to look beyond initial capital cost premiums and evaluate the life cycle cost benefits of low grade renewable energy sources.

HVAC Systems In green building, the need to provide occupants with a pleasant, comfortable yet energ y-ef f ic ient env i ronment is placing the mechanica l heating and

32 Building Strategies

cooling system at the centre of the design process as opposed to positioning it as a necessary evil that must somehow be accommodated within the building.

The base assumption that HVAC system design is based on fossil fuel-intensive centralized heating and cooling formats where the scope of energy recovery is confined to an air or water-side economizer control is now out of sync with the everincreasing life cycle energy efficiency goals being established.

D e cent r a l i z e d z one-ba s e d H VAC systems are now being applied on marketleading green buildings, such as Enermodal Engineering’s new LEED Platinum head office in Kitchener, Ont., where the anticipated energy savings will position this building as the most energyefficient office building in Canada. In this instance, a high performance air sourced heat pump system, using f lash injection technology on a variable speed drive scroll compressor, recovers enough heat from the ambient air (at temperatures as low as -30˚C) to provide complete heating and cooling requirements for the space. This approach is being used in t a nd e m w it h d e c e nt r a l i z e d e ne r g y recovery ventilators to satisfy fresh air requirements on a zone by zone basis.

This particular application is an ideal example of holistic design where the building fabric is insulated to R Values which negate the need for supplemental heating during peak winter loadings ba s e d on s out her n O nt a r io de si g n conditions. The shape and orientation of the building is also designed to maximize t he ut i l iz at ion of nat u ra l dayl ight, reducing the reliance on artificial lighting – a significant potential energy saving over the life cycle of the building.

Other technologies such as air and water source heat pumps, which were once considered practica l in less challenging climatic conditions such as Europe, are also being optimized for eff icient operation in North America a nd, in pa r t icu la r, Ca nada. Passive ventilation strategies applied effectively

in Europe for decades are now being modif ied through innovation creating hybrid systems that offer the best balance bet ween operating ef f icienc y and reliability.

Energy Efficiencies and Finances Cu r rent ma inst rea m g reen bu i ld ing programs offer incentives for energ y savings provided by renewable energy sources and recycled materials. However, based on current structures, they do not recognize the long-term impact from a ‘cost of ownership’ perspective that truly sustainable design strategies have in terms over the life cycle of a building.

Performance contracts in the form of public-private partnerships (P3) are now being seen as not only an effective format for establishing the financial structures for the implementation of a significant portion of public construction projects but an idea l strateg y for del ivering buildings that are optimized to achieve long-term sustainability for the end user.

The ultimate drive towards achieving designs that will achieve the best feasible net present value (or NPV) based on a 30-year building life cycle evaluation period can prove to be fertile ground for a holistic sustainable design approach.

The design and implementation of bu i ld i n g s a c ro s s Ca n a d a i s b ei n g revolutionized by the awakened social c o n s c i o u s n e s s t o w a r d s l o n g-t e r m sustainability coupled with prudent financial making. The current sense of design innovation within the construction industry as supported by continuing technological developments is providing the support structure needed to meet ever-increasing energy efficiency thresholds.

Effective energy-efficient design strategies in buildings are now becoming an industry p r e r e q u i s it e fo r l on g-t e r m f ut u r e sustainability — from both an environmental and financial perspective.

Dermot McMorrow, P.Eng., CIBSE, MASHRAE, is a development engineer of VRF and ERV technologies at Mitsubishi Electric Sales Canada Inc.

February/March 2010 33

Enterprising Canadians

Innovative Engineering

Shaping the skyline one building at a time, Read Jones Christoffersen has built its reputation on providing cost-effective, client-tailered solutions.

By Clare Tattersall

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More than 60 years ago, in 1958, John Read opened a small structural engineering practice in British Columbia’s most populous city. As he settled into his cramped office quarters, Read had high hopes for the fledgling business but never expected it to become one of the largest and most widely recognized consulting engineering firms in the country.

Joined by Per Christoffersen in 1951, and Peter Jones a year later, Read and his t wo partners branded the f irm Read Jones Christoffersen (RJC), which, today, has offices across Canada in Vancouver, Victoria, Nanaimo, Calgary, Edmonton and Toronto and touts more than 340 employees.

“We’re working on literally hundreds of projects at any given time,” says the firm’s managing director, Doug Clark, who joined RJC in 1974.

Since then, much has transpired. And although the firm’s namesakes are long gone, the company’s good name still lives on.

Recognized for its skill, expertise and developing innovative structural design and engineering solutions for all building types, RJC has expanded its core structural engineering practice throughout the years to include other specialties.

In 1964, the firm formed its parking garage division, which is dedicated to the functional design of parking facilities.

Today, RJC has received more awards for parking design than any other consulting engineering firm in Canada.

Approximately 20 years later, when many existing parking structures were showing signs of corrosion-related deterioration, the restoration division was formed. Originally focused on evaluating, restoring and protecting parking structures, this practice expanded to incorporate other types of structures including those containing post-tensioning systems.

Then, in the late ‘80s, the firm began to evaluate and restore existing building

34 Building Strategies

envelope systems. Soon after, building science was added as a practice area. “ We began by offering ser vices to restore wood frame condos and then larger buildings of all types,” says Clark.

“From that we expanded, looking after all aspects of the building envelope design including providing consulting services on new construction.”

Clark adds he expects this part of the business to evolve with the growing emphasis on “green” building, which the firm is committed to wholeheartedly.

“Our (goal) is (to) be one of the top firms in Canada with regard to offering sustainable design services within our fields of expertise,” he notes. “Building envelope design is directly tied in with energy use.

For instance, the better the energy efficiency of the cladding, the less cooling load on the air conditioning plant.”

Most recently, RJC officially launched an international division in 2007. Led by one of the firm’s principals, Gilbert Raynard, the international practice is working on more than 20 projects abroad, primarily in the U.S. But while expanding into the American market has offered an opportunity for the firm to diversify, it hasn’t been without its challenges. Of late, the downturn in the U.S. economy and rising Canadian dollar against the falling greenback has greatly impacted the building industry.

However, the firm expects business to once again pick up.

“The company’s standing in the engineering design and construction community has opened a lot of doors for the firm,” says Jeff Corbett, managing principal of RJC’s structural design team in Vancouver. “(RJC) is a leader in developing innovative structural methods.”

This encompasses the use of cast-in-place concrete flat plate construction in the firm’s first significant project, the Beach Town House Apartments in Vancouver’s west end, and the creation of a “mat system” for laying out rein-

Ritz-Carlton Vancouver

forcing steel in concrete slabs, which has become an industry standard and is being introduced into the Canadian Concrete Design Code.

However, “as far as innovation goes, we innovate as it serves the need of the project and client,” notes Corbett. “We don’t innovate just for the sake of trying something new.”

RJC’s dedication to not only meet but exceed clients’ needs, in addition to the firm’s diversity (in projects and services offered), has greatly contributed to its long-term success. But Corbett says the private, employee-owned company wouldn’t have survived and continued to thrive without the commitment of its people.

“Those who joined the firm virtually straight out of university are still here and are now the leaders in the company,” he says, adding the firm’s mentoring program and unique flat management structure make RJC a coveted place to work.

“By focusing on the professional development of our people, we’re creating satisfied employees who deliver great service and produce satisfied clients.”

This article was excerpted from the May/June 2008 issue of Construction Business.