While this version of the MR credits is an improvement over the second draft, it does not go far enough in separating out and balancing rewards for performance and transparency. The big problem is the Whole Building Life Cycle Assessment option (Option 4) in the Building Reuse and Whole Building Life Cycle Assessment credit, which also occurs in modified form in the Building Reuse with Additions option (Option 5).

The approach conflates performance and transparency by awarding up to 3 points for projects that "conduct a life cycle assessment of all the project's structure and enclosure that demonstrates a minimum of 10% reduction in at least 3 of the 6 impact categories listed...in comparison to a reference building." The 6 impact categories are Global warming potential, Depletion of the stratospheric ozone layer, Acidification, Eutrophication, Formation of tropospheric ozone, and Depletion of non-renewable energy resources.

There are many problems with this approach, but they are summarized in a Statement of Consensus on Driving Leadership in Performance and Transparency that was circulated the day before the release of LEED 2012v3 and is supported by major AE firms, environmental groups, and numerous others. One of the recommendations offered in the statement is this:

"Recognize the fundamental differences between performance standards and disclosure tools in LEED; address them separately, with distinct credits. LCA-based disclosure tools should not be used to evaluate performance because they cannot yet do so reliably."

The awarding of points for a reduction in 3 of 6 cherry-picked impact categories using LCA that relies on aggregated data sets whose accuracy for the specific materials used in a given building or assembly is highly doubtful is PRECISELY the type of practice that the Statement of Consensus argues against. If USGBC wants to encourage whole building LCAs, and the comparison of the results to a baseline, fine - that's transparency/disclosure, and will adequately encourage the development and refinement of the science and practice of LCA. However, we believe the above approach in fact rewards the use of LCA to measure actual performance, and this, we believe, is a grave policy error and indefensible given the immaturity of and inherent weaknesses in most current LCA methods.

Finally, there is the matter of the relative balance and weighting of performance vs. disclosure/transparency. All told, LCA-based approaches garner up to 5 points in this version of LEED -- up to 3 in the approach outlined above, and up to 2 more for EPDs in the Material Life Cycle Disclosure and Assessment credit. That's more than a third of ALL of the points available in the MR section (14 total by my count, not including those applicable to LEED Healthcare only). This seems way out of whack given the nascency of LCA tools and the demonstrated track record of leadership performance standards for building materials (such as FSC for wood) in driving actual market transformation in their respective industries. LEED 2012 will remain controversial until and unless performance and transparency are truly separated and balanced in the MR credits.