Looking beyond hyperbole to confirm the real data behind health claims for green buildings.
By Michael Cockram
The link between health and green building seems natural. More daylight, fresh air, and reduced emissions from fossil fuel read like a recipe for wellness. But there are those who use things like LEED certification as a marker of healthy building when the facts don’t always align with the claims.
Red Listed: The Bullitt Center in Seattle is aiming for Living Building Challenge (LBC) certification, so the team had to vet building products for compliance with LBCs Red List. The list prohibits the use of 14 potentially toxic ingredients (many of which are commonplace in building materials) to ensure a healthier environment for office workers.
For example, Duke Realty, an Indiana health-care-facility developer, extols on its website the healthy attributes of a recent project that achieved LEED Gold certification, asserting, “Green buildings typically have better indoor air quality than conventional facilities.” However, the certification was for LEED for Core & Shell. This category doesn’t include the finish-out of tenant spaces and avoids a primary culprit in indoor air quality: toxic emissions from finish materials.
On the other hand, a 2010 study done by Michigan State University titled “Effects of Green Buildings on Employee Health and Productivity” found that LEED buildings do create healthier work environments. Despite the fact that the scope of the research was limited to only two case studies (the Christman Building and the Michigan State University Federal Credit Union), the authors of the report concluded that “these preliminary studies lend support to expectations of improved IEQ [indoor environmental quality] and occupational health and public health outcomes from expanded use of green office buildings.” Expectations are not evidence, and the Michigan State researchers were aware of the limitations of drawing conclusions from subjective employee surveys, their method of evaluation in this study.
Common sense and a lot of science warn that breathing toxic chemical gases in unventilated or unexhausted environments is hazardous. That’s the presumptive logic on which this and similar studies are based. Future research will most likely broaden its scope to measure accurately the cause before extrapolating its effect.
Fact fishing and sound bites
This is why studies, particularly those of the preliminary kind, are so susceptible to distortion. A 2011 Fox News headline shouted out: “Green Buildings, Hazardous to Health?” Beyond that hyperbole, the story cherry-picked its way through an Institute of Medicine study on the potential impacts of climate change on IEQ. The story focused on the possible negative effects of “weatherization” methods such as adding insulation and tighter construction.
“To say something is green because you’ve increased tightness or insulation is inappropriate,” says Carnegie Mellon architecture professor Vivian Loftness, a coauthor of the study. She points to the passive-house technique of using heat-exchange ventilation as an example of green building that actually improves fresh-air delivery rates compared with conventional homes. “It’s a package deal; you don’t build supertight without a ventilation system,” she adds.
The Fox story also omitted the recommendations of the researchers, which called for updated codes, more testing, and regulation by the EPA of toxic emissions from materials.
Some researchers have criticized the U.S. Green Building Council (USGBC) for the fact that it’s possible to tailor a LEED Platinum certification without any indoor-air-quality credits. But the critics provide no data to show how LEED buildings actually perform.
The National Research Council of Canada released a study this year that is the most extensive to date on how green buildings perform in terms of indoor air quality. Comparing 12 pairs of conventional and green buildings (most were LEED-certified or candidates), the study found that the green buildings did have better indoor air quality. According to research-team member Guy Newsham, the data supported the premise that such buildings have lower levels of indoor pollutants and higher ratings for occupant well-being, among other positive attributes.