The Leadership in Energy and Environmental Design, or LEED, program is a green building rating system, designed to help incorporate sustainability elements into the design, construction, and operation of a building. Created by the United States Green Building Council (USGBC) in 1994, and licensed by the Canadian Green Building Council (CaGBC) in 2003, LEED has evolved with the building industry, expanded into various global markets, and is now considered one of the world’s most popular green building rating systems.
Unlike building codes and standards that set minimum performance thresholds and targets, LEED is voluntary, rewarding projects that go above and beyond the minimum. It consists of a handful of prerequisites – mandatory sustainability targets that every project must achieve – as well as dozens of optional credits that projects can elect to pursue. The more credits achieved, the higher the LEED rating, from Certified to Silver to Gold to Platinum.
The prerequisites and credits are also diverse, looking at sustainability features from all design, construction, and operation disciplines. From improving your building envelope to be better insulating and more durable, to increasing the efficiency of ventilation, heating, and cooling systems, to managing stormwater runoff, to utilizing materials and products from local industries thereby encouraging local economies, to favouring sustainable choices during operation and procurement, LEED strives to encourage sustainability in all aspects of a building, across a wide range of building types.
Recognizing that the relative importance of sustainability features may vary across building types, the USGBC developed several unique rating systems tailored to each. LEED for Healthcare, for example, has custom credits rewarding projects that save water and energy with healthcare specific equipment and systems. It also has several credits that provide patients and staffs with connections to nature and places of respite. LEED for Schools rewards projects that design facilities for flexible use, as well as focus on indoor air quality and mould prevention.
LEED for Neighbourhood Development, however, is probably the most unique rating system. Designed to certify entire neighbourhoods and cities, LEED-ND focuses on the sustainable practices of urban planning, transportation engineering, urban agriculture, and others on a master plan scale. Some of the unique credits include:
- Proximity of housing to jobs, measured in walkable distances
- Walkable neighbourhood and street design, including minimum sidewalk widths, a building-height-to-street-width ratio, limits on the amount of ‘blank facades’ (ie: those with no doorways, windows, or openings), and lower maximum vehicle speed limits to encourage pedestrian and bicycle travel
- Encouraging mixed use neighbourhoods through diverse housing choices and levels of affordability
- Dedicating permanent growing space for urban agriculture, including provisions in local bylaws to allow for such use
- Providing education facilities within walkable distances of residential neighbourhoods
- Establishing minimum energy performance requirements for residential, commercial, and institutional buildings, including single-family homes
Although this is a new and complex rating system, several projects in Canada have already achieved certification, including Dockside Green in British Columbia, as well as METROGATE here in Toronto. Additionally, although still being filled in, the Toronto Waterfront Area project has certified over 1.7 million square metres (18 million square feet) of mixed use development!
The LEED system, however, isn’t perfect.
Some critics view LEED as ‘point-chasing’, targeting no-cost / low-cost measures to achieve the desired level of certification versus measures that are more relevant to improving the sustainability of the building. Examples of this include providing bicycle racks and showering facilities for a building in the middle of nowhere, or providing charging stations for electric vehicles in smaller, more remote communities. Although these are sustainability measures, the likelihood of them being used are remote.
Other critics claim that LEED buildings are no more energy- or water-efficient that non-LEED buildings. Currently, there’s nothing mandating actual metering and tracking of utility data, and comparing the consumption of a LEED building versus a non-LEED building. It is an optional credit under most versions of the rating system, but there’s nothing forcing a project to firstly pursue this option, and secondly report findings publically.
In spite of these and other criticisms, few can argue with the impact LEED has had on the building sector. As of June 2015, the Canadian Green Building Council has certified over 2,250 buildings across Canada under the LEED program, while the U.S. Green Building Council has nearly 80,000 projects listed in their directory (combination of certified and candidate projects). Certified projects include hospitals, schools, coffee shops, offices, condominiums, banks, and single-family homes. LEED is beginning to be incorporated into building codes and standards in several jurisdictions.
- Newfoundland and Labrador requires LEED Silver for any buildings under their Build Better Buildings initiative
- LEED Silver is required for all projects administered under Infrastructure Ontario, which includes most hospitals, schools, and other publically funded projects
- Waterfront Toronto, a three-tiered organization created to responsibly manage the Port Lands in Toronto requires LEED Gold for all buildings within their jurisdiction
- The Town of East Gwillimbury in Ontario has required LEED Silver for all buildings in their municipality
- Halifax has committed that all municipal facilities achieve LEED Silver certification since 2005
While LEED is definitely not the end all and be all of sustainable buildings (look for future posts on the Living Building Challenge and Passive House!), it is a great example of what can be done to improve the sustainability of our built environment.