Kats: “There have been several hundred peer reviewed studies that document improvements in various aspects of health and productivity and greener more efficient design. Upgrading building energy efficiency typically improves building monitoring and occupant controls, and generally improves indoor air quality, not the other way around.”
Numerous websites have covered a recent Institute of Medicine report looking at the impact of climate change on indoor environments. The report is a good one – but very dry and probably uninteresting to anyone not involved in the building trade.
The Institute of Medicine report warns that the effort to counter climate change has spurred a shift to untested new materials and building retrofits that could limit and alter the air flow inside buildings.
Well, that’s one way to interpret it.
The report doesn’t even focus on real “green” buildings; rather, it looks at conventional energy efficiency upgrades that tighten the envelope of residential and commercial buildings. The issue in question is whether shifting external environmental factors due to climate change will negatively impact indoor air quality in buildings with less ventilation.
People spend the vast majority of their time in indoor environments and will thus experience many of the effects of climate change indoors. The outdoor environment permeates indoors in all but maximum-containment laboratory conditions. A building that was tightly sealed as a response to adverse outdoor conditions or because of efforts to reduce energy use might protect occupants from one set of problems but would increase their exposure to another: such buildings tend to have decreased ventilation rates, higher concentrations of indoor-emitted pollutants, and more occupants reporting health problems.
It’s an important question, but certainly nothing new. Designers have always known that if you make a building more air tight, you potentially trap moisture, mold and smoke. An energy-tight building can still be a “sick” building. That’s why there’s a big difference between energy-efficient buildings like and “green” buildings that take a whole-systems approach to ventilation, lighting and materials use.
The question addressed in this report is whether ventilation standards in energy-efficient buildings should be examined because of changing external factors. Unlike the headlines would suggest, it doesn’t make any bold, scary claims about green buildings killing your children.
We reached out to a few green building experts to get their reaction to the report and the resulting news coverage.
Aaron Buys, a buildings consultant with the Rocky Mountain Institute, says that the report highlights important issues that the industry has been dealing with for decades. (He also has a nice blog post on the subject over at RMI.)
The leap from this report to a headline that states “green buildings could harm your health” is unwarranted. This report is a proactive measure to counter problems in the future, not a warning of impending harm.
That said, it is a valid point that increased tightness in construction, especially in residential buildings, will probably necessitate a reconsideration of ventilation standards. A similar issue was encountered in the late 70’s and 80’s when code-required commercial building ventilation rates were drastically decreased to levels two to four times lower than today in an effort to decrease energy use. This caused many instances of what was dubbed “sick building syndrome” where building occupants got sick at much higher rates than usual in these under ventilated buildings.
His colleague at the Rocky Mountain Institute, Caroline Fluhrer, also weighed in:
Whether a building is energy efficient or not, adequate ventilation, moisture protection, etc. are always going to be important. And, as we move forward, specifying materials that don’t off-gas or have carcinogens is also important (we’ve made these mistakes in the past with asbestos and other materials). I think the ASHRAE Standard 62.1 and the LEED rating system both emphasize indoor air quality and human health as a priority. My personal opinion is that indoor environmental quality is not being sacrificed in our pursuit of greater energy efficiency.
Finally, Greg Kats, author of Greening Our Built World: Costs, Benefits, and Strategies, explains the overwhelmingly positive impact of green buildings on health and productivity:
The concern that greening and efficiency has an adverse health impact is a bit like calling seat belts a threat to public health because they could cause abrasion by rubbing.
There have been several hundred peer reviewed studies that document improvements in various aspects of health and productivity and greener more efficient design. Upgrading building energy efficiency typically improves building monitoring and occupant controls, and generally improves indoor air quality, not the other way around.
The standard for green building design, LEED, has indoor air quality as one of its 5 areas of performance. Typically, improvements in green buildings’ indoor air quality include improved ventilation, greater tenant controls, and healthier materials (think low VOC paints) and cleaning supplies. These products for LEED have to be third party tested against standards before being accepted to qualify for LEED points, so LEED is driving much healthier design and materials.
In the 1970s and 1980s some poor energy efficiency design cut ventilation, but today this is the exception in commercial buildings. Tightening envelopes of homes can – with no other changes – reduce air exchanges and increase indoor pollutant concentration. But professionally done, efficiency upgrades increase air quality.
But that doesn’t make the best headline, does it?