Architects are becoming increasingly aware of the need for concern about the negative impact that buildings have on our environment. The broad question might read: “What is sustainable design?” The more refined question might ask: “How green is it?” When working to both create and market sustainable design, it is increasingly important to be able to make definitive assessments so that proposals may be quantified and compared.

If "green building" is design that incorporates improved environmental performance, precise knowledge of the specific performance criteria is essential to the success of the project.

What is LEED™?
The Leadership in Energy and Environmental Design (LEED™) Green Building Rating System is an assessment tool that has been designed to answer that question. It is currently being promoted throughout North America for the evaluation and promotion of sustainable design. The goal of LEED™ is to initiate and promote practices, which limit the negative impact of buildings on the environment and occupants. The design guideline is intended to prevent exaggerated or false claims of sustainability and to provide a standard of measurement.

“The Leadership in Energy and Environmental Design (LEED™) Green Building rating system represents the US Green Building Council’s effort to provide a national standard to what constitutes “green building”. Through its use as a design guideline and third-party certification tool, it aims to improve occupant well-being, environmental performance and economic returns of buildings, using established and innovative practices, standards and technologies.”

In addition to creating a working definition of “green building”, LEED promotes integrated, whole-building integrated design practices (IDP). In fact, most practitioners currently striving to achieve LEED certification, cite the IDP as essential to achieving adequate levels of green design. IDP requires a true team approach to building design that commences with the first sketch. The primary objective of LEED is to transform existing building markets so that sustainable design, construction and operations practices become mainstream. LEED accreditation aids in identifying leaders in ‘green’ design through an incentive based program. Such acknowledgement is intended to serve as a marketing tool and to raise consumer awareness of the importance of ‘green’ design.

The current LEED standard is LEED v.2.1, link released in November 2002, evolved through consensus-based committee work. Currently there are several new versions of LEED in development, including a modified “Canadian” draft version that is being developed by the Canadian Green Building Council. link

The structure of the LEED Rating System is segmented into sections, credits and points. The five key sections (initiatives) are identified as sustainable sites, water efficiency, energy and atmosphere, materials and resources, and indoor environmental quality. In addition to these five initiatives, a sixth section is reserved for design process and innovation. This framework definition of sustainable design extends former ideas of energy efficient design to include aspects that encompass the whole building, all of its systems, and all questions related to site development. Most sections include one or more basic prerequisite items. These must be fulfilled or the balance of the points in the category will not be counted.

The LEED framework is designed to capture environmental, economic and human health benefits.

It is interesting that the images included here are all from buildings that are widely thought to be “green”, but that are not LEED certified. In LEED related research at the University of Waterloo School of Architecture, estimated LEED assessments have been conducted “after the fact” on all of these buildings. Some perform quite well, other older ones, surprisingly poorly. Many could be LEED certified were they to choose to apply for the award. Stephen Carpenter of Enermodal Engineering was responsible for the engineering of Green on the Grand, Canada’s first C-2000 building. Carpenter is now a LEED Accredited Professional. He concedes that Green on the Grand would have been designed differently – better -- had LEED been available at the time of its building. From an energy and site design perspective, the building fares well. Different decisions regarding the number of operable windows would have resulted from LEED based notions of occupant comfort and control. GREEN BUILDINGS DON'T HAVE TO BE UGLY....

Sustainable sites deals primarily with issues of site selection, site access and site design (materials, density, drainage). The prerequisite concerns erosion and sedimentation control on site. There are eight credits offering a total of 14 potential points. The development of sustainable site design is seen as a critical starting point for an attitude towards the entire building design in the IDP.

Vancouver Public Library. Moshe Safdie and Associates with Downs Archambault and Partners.
Credit 7.2 Landscape & Exterior Design to Reduce Heat Islands (roof)

Green on the Grand, Snider Reichard and March Architects
Credit 6.1 Stormwater Management, Rate and Quantity

Water efficiency is the smallest section comprising only three credits, worth 5 points. This section deals with landscaping, wastewater treatment and water use reduction. Items such as Living Machines™, use of the Waterloo Biofilter™, waterless urinals and composting toilets can be rewarded with points in this category.

YMCA Environmental Learning Centre, Charles Simon Architect
Credit 2 Innovative Wastewater Technologies: Living Machine™

Energy and atmosphere, includes three prerequisites – fundamental building systems commissioning, minimum energy performance, and CFC reduction in HVAC&R equipment. The prerequisites are followed by six credits for energy performance, renewable energy and additional building monitoring, with a potential value of eight points. Prior to the adoption of LEED, energy efficiency might have been the only motivation to improving design strategies. Within the holistic sustainable design framework provided by LEED, the relative importance of these issues has been revised to represent only 25% of the potential credits.

BC Gas (Terasan Gas) Musson, Cattell Mackey Partnership
Prereq 2: Minimum Energy Performance: Solar shading to reduce energy consumption.

Revenue Canada, Surrey, BC. Busby+Associates
Prereq 2: Minimum Energy Performance: Solar shading to reduce energy consumption.

Materials and resources, with 13 points generated in seven credits, this section has only one prerequisite: storage and collection of recyclables. The credits focus on building reuse; waste management; reused, recycled or certified materials; as well as local or regional materials.

Liu Centre for Asian Studies, UBC, Architectura
Credit 4 Recycled Content (timber used in roof)

Telus, Vancouver, Busby+Associates
Credit 1 Building Reuse (this building reused the concrete structure)

BC Gas (Terasan Gas) Musson, Cattell Mackey Partnership
Credit 3 Resource Reuse. This project was successful in the use of Flyash Concrete which is currently seen as the “green” solution to concrete use as regular concrete is associated with high embodied energy costs.

C.K. Choi Institute for Asian Studies, UBC, Matsuaki Wright Architects
Credit 4 Recycled Content (both the timber frame and brick)

Indoor environment quality is the largest category with two prerequisites, IAQ performance and environmental tobacco smoke control, eight credits and a total of 15 points. The credits in the indoor environment quality cover many issues of air quality, including ventilation and carbon dioxide monitoring, low-emitting materials, construction IAQ, controllability of systems, thermal comfort and daylight access. This category places high emphasis on occupant comfort and well-being – issues that are not addressed in other mandatory code requirements – this category falling outside issues of life safety, structural integrity and minimum energy requirements.

Mountain Equipment Coop, Toronto, Stone Kohn and Vogt Architects
Credit 8 Daylighting

U of T Bahen Centre for Information Technology, Diamond Architects with Allen Kani Associates
Credit 8 Daylighting

Richmond City Hall, Richmond, B.C., Hotson Bakker with KPMB Architects
Credit 8 Daylighting

Innovation and design process allows a building to obtain as many as four design innovation points, as well as one additional point for including a LEED accredited professional in the design process. The design innovation points may be awarded for achievements such as lifecycle analysis, community development or education of occupants. Substantially exceeding one of the earlier credits, may also merit an innovation point.

CMHC Healthy House, Martin Leifhebber Architect, Toronto, Ontario
Potentially off grid house in urban setting.

Caisse de Depots et Placements, Montreal
Double skin wall construction.

YMCA Environmental Learning Centre, Residence Building, Charles Simon Architect
Custom masonry heater.

The collected LEED base sections amount to 64 points in 32 credit categories. Adding the 5 points for Innovation & Design Process results in a potential of 69 points. Buildings are accredited by the number of points gained: 26 to 32 point is LEED certified; 33 to 38 points is LEED Silver; 39 to 51 is LEED Gold, and; LEED Platinum is awarded to projects with 52 or more points. By awarding a medal to successful buildings, LEED is an incentive-based system, which can be easily understood by designers and clients alike. It can also be used as a forceful marketing tool, by “brand naming” buildings with the LEED award label. Several cities in the United States have adopted LEED Silver, for instance, as the minimum standard for all new municipal construction.

How do I get my building LEED™ certified?
The LEED accreditation process occurs in two stages: project registration and building certification. A project can be registered on-line in less than 30 minutes, to initiate the LEED accreditation process. (The URL is http://www.usgbc.org/LEED/Register.asp) Registration fees vary based on membership status of the design team and square footage of the building. The minimum registration fee is $750, with maximum fees as high as $3750 for registration into the program. The registration form requests a variety of information where available, such as the project team, program data and LEED checklist information. The registration fee includes two credit interpretations, a service which mitigates difficulties encountered while applying LEED credit standards to special building circumstances. Also included in the registration fee, is access to LEED letter templates for preparing the application submittals.

Once a project is registered, the project team can begin compiling the necessary documentation for the submittal. All of the prerequisites must be met, and a sufficient number of points earned, to achieve accreditation. The submittal is completed as a binder or CD document, and is best achieved with the assistance of a certified LEED professional. A separate template is completed for each LEED prerequisite and credit. The accreditation submittal is accompanied by a second fee (between $1500 and $7500) again, depending on membership status and square footage of the project. The submittal document is reviewed, and within 30 days, notification is sent in regards to anticipated credits achieved, denied or pending. For submittals in LEED 2.1, an additional audit is performed on 6 random LEED credits. When prerequisites and credits have been acknowledged and/or audits have been completed, the project team is notified of the accreditation ruling. Where there is a question of credit(s) denied, an appeal process is in place to re-visit these issues.

Technical support is available in three ways: LEED Reference Guide (available at http://www.usgbc.org/Docs/LEEDdocs/LEED_RS_v2-1.pdf ), LEED accredited professional, and credit interpretation. The LEED Reference Guide is the initial document that identifies the intent, requirements, technologies and strategies for each prerequisite and credit. The Reference Guide also identifies the pertinent reference standards for each credit and prerequisite. The use of a LEED accredited professional is worth one credit. The LEED professional is trained in the details of the LEED program and can facility sustainable design and LEED application documents. Credit interpretations requests (CIR) can be filed with the USGBC via an online form. All previously logged CIRs are available on-line for access by registered project contacts.

The LEED program is branching out to provide assessments catered to a variety of building conditions (including core and shell, commercial interiors and existing buildings).

Comparing LEED™ with other Standards:
Current reference standards, such as ASHRAE 90.1 and the MNECB address only issues of energy conservation. Neither of these addresses site usage, materiality, air quality or water efficiency, to any significant degree. The national and provincial building codes, again, do not make any reference to sustainable site use (these are concerned solely with utilitarian issues of parking and fire access), water efficiency, air quality or materiality.

The British predecessor to LEED™, the British Research Establishment’s Environmental Assessment Method (BREEAM), is a complex system with a broader range of credit values. The points system is cumbersome and the efficiency and accessibility of the LEED checklist. LEED is the first program to identify the larger scope of ‘green’ building issues, categorize the design items and develop such a simplified accounting system for credits. With each item being valued at 1 point, and an easy to understand breakdown, LEED is accessible to both designer and client.

LEED™ in Canada:
British Columbia is a member of the Cascadia branch of the USGBC. As a joint enterprise between the Ministry of Competition, Science and Enterprise, the City of Vancouver, the Greater Vancouver Regional District (GVRD), BC Buildings Corporation, BC Hydro and BC Gas, the LEED BC Adaptation Guide has recently been submitted for USGBC approval. The Canada Green Building Council has further developed the LEED BC guidelines as a draft LEED Canada document for national application. New in these versions are the equivalent and pertinent Canadian and regional standards for energy efficiency and building practice, including the Model National Energy Code for Buildings (MNECB) and the Commercial Building Incentive Program (CBIP). While the essence of the LEED structure is unchanged, the program becomes much more applicable to the Canadian building context. The only significant change to LEED BC is the addition of one prerequisite to acknowledge the necessary protection of riparian wetlands along the coast of British Columbia.

Until the draft version of LEED Canada is approved and adopted, LEED projects in Canada will continue to pursue the LEED 2.0 standard provided by the USGBC. While there are many Canadian projects (46 as of Oct 28, 2003, 27 of which are in BC) registered on the LEED website, only two have been certified to date – White Rock Operations Center and the Vancouver Island Technology Park. Both of these achieved the LEED Gold standard.

The Vancouver Island Technology Park, designed by Idealink and Bunting Coady Architects, with Keen Engineering, was awarded LEED Gold in February 2002. The project involved the reuse and redevelopment of an existing hospital facility (165,000 square feet), converted to high tech office space, as well as the construction of an additional 235,000 square feet of building. The project scored 41 out of 69 potential points. The project was recognized for its innovation in developing an integrated site water management plan and rehabilitation program for Salmon Bear Creek that is used to treat stormwater from other sites and which provides for rehabilitation of local creek. VITP also participated in a transportation program that resulted in promotion of alternative transportation – which can be key to gaining several associated LEED points. VITP also developed of green building guidelines and an educational program for tenants. Occupant education has been found to be essential to the success of many sustainable projects beyond the point of building commissioning.

In July 2003 the White Rock Operations Centre in British Columbia became the first new building in Canada to achieve LEED Gold. The project was designed by Busby + Associates with Keen Engineering and Flagel Engineering. The building scored 44 of a potential 69 points.

The City of White Rock, through the design of the White Rock Operations Centre, is attempting to provide community leadership in more environmentally responsible building practices. Some of the initiatives include: a green roof to reduce the urban heat island effect; gravel parking lots to maximize infiltration of rainwater, and the revegetation of nearly 400 square metres of asphalt with native species. The Centre also uses stormwater collection for toilet flushing and to help heat and cool the building.

There is a commitment to purchase renewable energy, as well as to generate solar electric power onsite. High efficiency fixtures and mechanical systems were selected to reduce energy consumption. Indoor air quality was deemed important by the City, so this has been achieved by the use of natural ventilation, operable windows, and direct ventilation where necessitated by specific building use.

Daylighting is an important LEED criteria. It has been employed as a main feature in the building, incorporating sunshades, wall trellis, larger roof overhangs, and light shelves to optimize lighting while at the same time, controlling heat gain. Building materials were selected to ensure that all new materials were regionally manufactured and that ninety-nine percent of the original building was recycled, either in the new building or others. This succeeded in diverting almost a million tonnes of waste from landfill.

Of recent note, the soon to open permanent circus bigtop, "Tohu", in Montreal is said to be going for LEED Gold. It would certainly be the first building of its particular (limited!) type to win this type of LEED Award. It is situated adjacent to a massive landfill/garbage dump north of Hwy#40. The methane gas from the landfill is being harvested to produce energy in the form of hot water that will be used to provide radiant heat to the floor in the building. Many resued steel beams can be seen in the interior. A large trombe wall on the south face will assist with both heating and cooling the building.

View of Tohu Bigtop under construction. March 2004. The unfinished part of the circular sandwich panel precast wall system is to contain the south facing trombe wall when complete.

Hopes are that wide adoption of LEED in Canada will result in an increasing number of certified buildings and a general lowering of the negative impact of building on our environment. By recognizing environmental leadership in the building industry, LEED hopes to stimulate green competition, thereby raising consumer awareness of green building benefits that will ultimately transform the building market.

This article is the draft version of the piece recently published in the Canadian Architect, January 2004.

Terri Meyer Boake BES B.Arch M.Arch
Associate Professor, School of Architecture, University of Waterloo

Caroline Prochazka BES
Masters Candidate, School of Architecture, University of Waterloo