Responsible for approximately forty per cent of carbon emissions, and another forty per cent of energy consumption, buildings are an obvious place to start thinking about ways to reduce pollution and use energy more effectively. In 1998, the US Green Building Council did just that by introducing the Leadership in Energy and Environmental Design (LEED) criteria. By setting standards for the development and construction of green buildings, the rating system encourages and accelerates the adoption of sustainable green building and development practices through a series of design tools and performance criteria.
In theory, LEED is supposed to promote a holistic approach to sustainability by recognizing the importance of both human and environmental health. Beginning with sustainable site development as it basis, the system considers a building’s impact in many ways, focusing on water efficiency, energy efficiency, materials selection and indoor environmental quality. Certain sub-divisions of the system include additional assessments, such as LEED Canada for Homes, which outlines a location and linkages category as well as a general awareness and education category.
In all of the criteria’s various forms, certification is based on the total score achieved by way of an independent review and an audit of selected credits. Four possible levels of certification currently exist (certified, silver, gold and platinum), enabling review teams to be flexible enough to accommodate a wide range of green building strategies with varying constraints and goals.
However, the system is not without its shortfalls. For one thing, observers believe LEED ought to measure the impact of buildings over time. As a design tool used predominantly during the development stages of a project, LEED does not concern itself necessarily with performance-based standards. Furthermore, as it was conceived in the United States, the system is heavily geared towards dealing with North American climates above all else. While the most recent version hopes to address climate-specific design, in the meantime planners and architects are limited in their ability to apply the standards to particular contexts; indeed, contexts where the need isn’t necessarily most dire. High growth regions in the developing world are where LEED will be crucial to creating sustainable societies.
Perhaps the deepest criticism of LEED, however, is the fact that in concerning itself specifically with buildings and buildings alone, the system is ignoring the larger context in which buildings operate. Indeed, buildings exist for the purpose of housing people, but the larger systems, in which people operate, including transportation and social networks, are of equal environmental and human concern. In response, U.S. Green Building Council fostered the development of LEED Neighbourhood, which attempts to address the overarching needs of urban planning and city building. However, LEED Neighbourhood has come under fire for shortcomings of its own.
Nevertheless, the burgeoning popularity and acceptance of LEED, compounded by a wide range of private sector and government support, says a great deal about society’s collective interest in dealing with the environmental impact of buildings. With the goal of achieving and demonstrating sustainability, the reasons for certifying are endless. Whether it’s a question of gaining recognition for green building efforts, qualifying for a growing array of government incentives, or simply contributing to a growing green building knowledge base, LEED is certainly, at the very least, a step in the right direction.