Life-Cycle Assessment for Buildings: Seeking the Holy Grail

Food bought in a supermarket is labeled with a standard nutrition form that tells you the amount of nutrients, salt, and fat contained in each serving. Someday building materials at the supply yard may also have a label, listing each product’s contribution to global warming, ozone depletion, acid rain, habitat loss, and a handful of other environmental indicators. Eventually, whole buildings might be measured based on their performance against a similar set of indicators. When that day comes, the label or rating system will be the result of an environmental life-cycle assessment (LCA).

While standardized labels on building products are not yet a reality (at least not in North America), the science that will make it possible is rapidly becoming more sophisticated and more widely used. “I’ve been getting new signals just in the past few months that the field is really taking off in the U.S.,” reports LCA expert Greg Norris of Sylvatica, Inc. in North Berwick, Maine. While performing full LCA studies is still a job best left to the experts, building professionals are increasingly likely to encounter LCA-based data or use software tools that compile the results of studies done by others. To be effective in this setting, it is important to have a good understanding of the context in which those data and tools are created. This article describes LCA in a nutshell, presents some of the challenges faced by LCA practitioners and users today, outlines the most promising U.S. initiatives to address those challenges, and looks at the implications of this rapidly evolving field for designers and other building professionals.