The Wait Is Over For A LEED Life Cycle Component
By Scott Kriner, Green Metal Consulting
After more than four years of committee work and months of anticipation this year, the USGBC has finally introduced a Life Cycle Assessment of Building Assemblies and Materials component to the LEED 2009 program as one of several Pilot Credits. The new LCA credit is one of six new Pilot Credits.
Project teams that find any of the new pilot credits applicable to their LEED registered projects are being encouraged to participate in the pilot testing of those credits. A project that participates in a credit’s pilot and submits feedback to USGBC will receive one point in the Innovation & Design credit. Since the pilot credits are not yet officially part of the LEED program, points will not be awarded for achieving the pilot credit itself.
The LCA pilot credit, if formally enacted later, would replace 5 points from MR Credits 1.1, 4 and 5, which refer to Building Reuse, Recycled Content and Regional Materials. A USGBC-approved Environmental Impact Calculator is used to identify and calculate environmental estimates on generic building assemblies in categories which include exterior walls and roofs. A Credit Calculator then calculates the LCA impact score and the points to be awarded. The LCA score is between 0 and 100, and is based on how much better than average the rated assemblies perform. The LCA score is then converted into 1-5 points in the Credit.
Currently the only USGBC-approved Environmental Impact Calculator is the ATHENA Institute’s EcoCalculator for Assemblies. What does this mean for metal roof or wall assemblies? Well, the current generic pre-defined assemblies in the EcoCalculator tool include some that contain the material “steel cladding”. However, much of the environmental impact data behind the “steel cladding” component is either questionable, outdated or missing. Fortunately the metal construction industry is making progress in populating the necessary Life Cycle Inventory databases with up-to-date North American-based data on steel, aluminum, zinc and copper materials. Environmental impact data on the processes used to fabricate metal roof and wall components are also being assessed. During the piloting period, there is a good chance that more meaningful data will be available for the ATHENA LCA tool.
Other questions remain with the newly announced LCA Pilot Credit. One concern is how a project design team that specifies a particular assembly, but one that is not part of the generic pre-defined list of assemblies, properly determines the LCA score and points. The ATHENA tools include the Impact Estimator which should be able to generate environmental impact data for any material/assembly provided adequate LCI data are available. The present description of the Life Cycle Assessment is a bit sketchy on this subject. Time will tell.
Scott Kriner, MCA's Technical Director, is the president and founder of Green Metal Consulting Inc. He is a LEED Accredited Professional who began his career in the metal construction industry in 1981. His company is a member of the U.S. Green Building Council, the California Association of Building Energy Consultants and the Residential Energy Services Network (RESNET). Scott can be reached by email at skriner1@verizon.net, or by phone at (610) 966-2430. You can also visit him on the web at www.greenmetalconsulting.com.
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