Leeding the Way
Over the past 10 years in North America, environmental problems related to the building industry have been moving more to centre stage. Green building rating systems have been developed and have gaine...
Over the past 10 years in North America, environmental problems related to the building industry have been moving more to centre stage. Green building rating systems have been developed and have gained popularity. One of those rating systems, the LEED (Leadership in Energy and Environmental Design) Green Building Rating System, is growing in importance to both U.S. and Canadian consulting engineers.
Commercial and residential buildings account for about one third of Canada’s use of energy and production of greenhouse gases, which per capita is the third highest of countries in the Organization for Economic Co-operation and Development (OECD). Building operation also contributes to Canada’s high per capita use of water, which is second highest in the world. Building construction and demolition places other burdens on the environment, through the harvesting, manufacture and transportation of building components, as well as the disposal of waste. Worldwide construction accounts for 40% of raw materials used. And the decision to construct a building can entail the destruction of greenfields and habitat, and the disruption of water migration patterns.
Every building involves many players: the design team (building owners, architects, engineers and consultants); the construction team (materials manufacturers, contractors and waste haulers); the maintenance staff and the occupants. Efforts to reduce building-related environmental problems need to take into account the breadth and interconnections of the whole picture.
Because the North American business community is averse to regulation and since there is substantial momentum for carrying on traditional building design practices, legislative measures have not succeeded in checking the environmental impacts of construction. Existing codes, standards and incentives have tended to address isolated parts of the overall problem, but a broader approach is needed.
The LEED system has six credit categories:
sustainable sites: low-impact transportation, stormwater management, habitat protection, urban redevelopment, light pollution prevention;
water efficiency: minimizing use of potable water for irrigation and toilet flushing, minimizing effluent volumes to municipal treatment;
energy and atmosphere: minimizing use of non-renewable energy, protecting ozone layer;
materials and resources: reusing existing building, reusing materials, using recycled materials;
indoor environmental quality: improvement of ventilation, individual control of work environment, low-emitting materials, daylighting and views; and
innovation: education, regionalism, new/better ways of meeting intent of credits.
LEED was created by the United States Green Building Council, which unveiled its first version in 1998. A second version, LEED 2.0, was released two years later. By June 2003, there were:
820 building projects registered in the process leading to LEED certification
115 million square feet of building involved in these projects
projects registered in 48 states and seven countries
53 LEED-certified projects
40 registered Canadian LEED projects in six out of 10 provinces, and
many other projects influenced by LEED but not registered.
There is also a credential called the LEED Accredited Professional. Currently 300 people have obtained the certification in Canada, and more than 3,000 people have written the examination worldwide.
Many U.S. federal agencies and the state governments of California, Maryland, Massachusetts, New Jersey, New York State, Oregon, and Pennsylvania have recognized the value of the LEED system.
In Canada, The 18,000 member Association of Professional Engineers and Geoscientists of British Columbia (APEGBC) voted in 2001 to endorse the LEED model as the preferred method for building environmental assessment on a province-wide basis.
As LEED gained popularity in British Columbia, a partnership called the LEED-BC Steering Committee was formed to regionalize the standard. The partners included municipal, regional and provincial governments as well as the BC Buildings Corporation and the local utilities BCGas (now Terasen) and BC Hydro. The steering committee financed and supervised the development of LEED-BC, and submitted it to the U.S. Green Building Council for review. It received approval this June and is expected to be operational by September 2003. The Greater Vancouver Regional District board has now voted to use LEED-BC for its own buildings, and to promote it among its 21 municipalities. The City of Vancouver is considering the system for all city-owned buildings, while the Bid Book for the successful 2010 Winter Olympics states that all six new athletic facilities shall meet LEED or similar standards. In Alberta, the city of Calgary has approved a sustainable building policy based on the principles of LEED and has directed that the larger city-owned buildings be built to a LEED Silver standard.
Canada Green Building Council
Meanwhile, it is apparent that a Canada-wide organization is needed to develop and administer a contextualized standard, so that Canadian design firms can work with their locally relevant standards and techniques.
Begun as a part of the Royal Architectural Institute of Canada, the so-called Sustainable Buildings Canada Committee relaunched this year as the Canada Green Building Council (CaGBC). The new council’s objective is “to promote the design, construction and operation of buildings that are environmentally responsible, profitable and healthy places to live and work.” Its 22 members include engineers as well as architects, developers, manufacturers and government officials. The Canada Green Building Council is one of the eight founding organizations of the World Green Building Council.
The Canadian council encourages the use of not only LEED, but other environmental rating systems such as BREEAM Green Leaf, the Eco-Rating Program, and GBTool. Meanwhile, the council’s LEED Steering committee is finalizing a LEED Canada Adaptation Guide to submit for approval by the U.S. Green Building Council. It will be a framework document for Canada, possibly with provincial supplements to recognize regional divergences.
Membership of the Canada Green Building Council, which is by company or organization rather than by individuals, has increased from 45 in January 2003 to 107 by July. It receives consistent and ongoing support and encouragement from the Association of Consulting Engineers in Canada.
Kevin Hydes, P.Eng. is a principal of Keen Engineering in Vancouver and an editorial advisor to Canadian Consulting Engineer. He and Joe Van Belleghem, a B.C. developer, are on the boards of both the Canada Green Building Council and the U.S. Green Building Council. Rosamund Hyde, Ph.D. is a sustainable building researcher with Keen Engineering, Vancouver. See www.usgbc.org, www.worldgbc.org and wwww.cagbc.org
Study: White Rock Operations Building, B.C.
By Greg Scott, P.Eng., Corporation of the City of White Rock
The White Rock Operation Building in the City of White Rock south of Vancouver was designed through an integrated design approach as a green building using the LEED system as a guide. Completed this spring, the facility is used by public works and engineering staff, and it houses Environment Canada’s weather monitoring stations for the region.
The site was formerly a wastewater treatment plant, which created unique opportunities. The city’s engineering group redirected some of the existing storm drainage lines to discharge through an existing large, round, concrete in-ground storage tank beside the building. The tank then served double-duty both as a 108,000-gallon stormwater detention tank and as a source of water for non-potable uses in the new building.
The water in the tank provides heat to the building through the use of a water source heat pump. The old foundation of the treatment plant and its clarifiers provided the foundation and mec
hanical and electrical rooms for the facility.
The stored stormwater is used for irrigation, flushing toilets, washing municipal vehicles etc. In this way, the building reduces its annual potable water use from 512,000 gallons to 57,000 gallons — an 88% reduction.
White Rock is located on the ocean, so has relatively low summer temperatures. Operable windows provide natural ventilation and cross ventilation, and exterior shading devices include a trellis on the south side. A highly reflective albedo roofing material helps to reduce the urban heat island effect, while on part of the building is a vegetative “green roof.” These cooling design features eliminate the need for mechanical cooling.
White Rock is one of the sunniest areas of the Lower Mainland, with about 25% more sunshine than in Vancouver. This solar energy is captured using photovoltaics and solar collection tubes. The photovoltaics, a 2.5kW array mounted on the west side of the building’s roof, provide the first stage of heating to the domestic hot water system and hydronic heating.
The domestic water is also heated through a water-source heat pump, which moves heat energy from the stormwater storage tank to the hot water tank. This heat pump uses about 10,000 kWh per year to move about 30,000 kWh of heat into the building, displacing the use of about 100 GJ of natural gas. The building’s annual greenhouse gas emissions are reduced by more than 5,000 kg CO2 as a result.
The building is fully supplied with green power, from the local utility and from its own photovoltaic installation, so electricity used in the building is emission-free.
The White Rock Operations building has been submitted for LEED certification at the Gold level. Besides its exemplary conservation of water and energy, it was constructed with recycled products, achieving a 97% diversion of solid waste from the landfill.
Owner/client: Corporation of the City of White Rock (Greg Scott, P.Eng.)
Prime consultant/architect: Busby + Associates (David Dove)
Structural: Fast and Epp (Duane Palibroda, P.Eng.)
Mechanical: Keen Engineering (Blair McCarry, P.Eng.)
Electrical: Flagel Lewandowski (Jon Zbarsky P.Eng.)