The Yale360 blog had a post a week ago on LEED and it’s apparent failure to protect human health. I think LEED has done a lot to raise general awareness in the industry regarding energy and environmental issues when it comes to how buildings are designed, constructed and operated. However, I cringe when I hear people singing it’s praises and worshiping all things USGBC. I’m not an ardent critic, but I think the entire rating system must be taken with a grain of salt. My main criticism of LEED is that it is a design exercise with very little emphasis placed on follow up activities (one exception being EAc5 for M&V). This is true of testing for indoor air quality. The lack of testing is understandable to some degree, once a building a built the owner has less incentive to “do right”.

Personally, I think if designers can get the source control for indoor air pollutants right using the current best practices, construct a decent envelope and ventilate properly (i.e., to the ASHRAE 62.1 level and not necessarily to the 30% over-ventilation that the USGBC calls for) than the building will have far better IAQ than the average building. Whether or not this qualifies as “protecting human health” I can’t say. To my knowledge there hasn’t been an extensive epidemiological study to this end (including the 62.1 ventilation levels, but I suspect the ASHRAE committee errs on the conservative side when setting these standards, so why over-ventilate at an energy penalty with no medically proven positive health effects?).

Equal uncertainty abounds on the energy side of the LEED equation. Some say the buildings generally perform better (.pdf), others disagree (.pdf). Nevertheless, not enough is done to verify any of the purported benefits of LEED.

LEED is currently a great marketing tool but more verification work is required to make it anything more.