The U.S. Green Building Council’s (USGBC) Life Cycle Assessment working group has developed initial recommendations for incorporating Life Cycle Assessment (LCA) of building materials as part of the continuous improvement of LEED Green Building Rating System. The recommendations include short and long term implementation strategies as well as technical details regarding LCA methodology.
LCA is a scientific methodology that holistically evaluates the environmental impact of a product throughout its life cycle: from the extraction or harvesting of raw materials through processing, manufacture, installation, use, and ultimate disposal or recycling. In buildings it can be used to compare the environmental benefits or detriments of options available to the design team. “Until now, there hasn’t been much work done incorporating LCA into U.S. building practice because of limited research,” said Tom Hicks, Vice President, U.S. Green Building Council. “We are venturing into new territory, but as the nation’s leading green building organization USGBC has a responsibility to ensure that LEED's evolution addresses LCA in a meaningful and relevant manner.” The LCA working group’s recommendation for an initial approach is to undertake LCA of the assemblies that constitute a building’s structure and envelope. The assemblies will be ranked according to their environmental impact, with LEED credits awarded accordingly. This will provide a relatively quick, yet significant, infusion of LCA within LEED. USGBC's long term objective is to make LCA a credible component of integrated design, thereby ensuring that the environmental performance of the whole building takes into account the complete building life cycle. With the working group's reports now in hand, the LEED Steering Committee will begin considering the recommendations of the LCA Working Groups with a goal of completing an LCA plan by the end of 2007. To facilitate the plan's development and ensure technical and practical effectiveness, USGBC is contracting with internationally respected LCA expert Greg Norris, Ph.D., President of Sylvatica, Inc., as project manager. View the reports: November 06 reportDecember 06 report USGBC has long recognized the value of incorporating LCA-based credits into the LEED rating system. Any LCA-based LEED credit must meet two essential requirements: 1. Level playing field: The LCA basis of the proposed LEED credits must provide a level playing field – one that is fair and objective – based on a consistent methodology applied across all products and at all stages of their production transport use and disposal or recycling at end of life. 2. Practical use: LCA is inherently complex and the LCA tools and methods used for LCA-based LEED credits must be very practical and intuitive for designers, specifiers and facilities managers to use at appropriate stages in the life cycle of buildings. The working groups are part of the “LCA into LEED” project, which was commissioned as an advisory group by the LEED Steering Committee to engage critical LCA stakeholders. Over 60 volunteers representing LCA experts, manufacturers, trade associations, academia, federal government, nonprofits, and USGBC LEED committees are involved in the project.