Review of some effects of climate change on indoor environmental quality and health and associated no-regrets mitigation measures

• Many of the health effects of climate change will result from indoor exposures.
• These climate-related health effects can be reduced by changes to buildings.
• Many of the changes to buildings will improve health irrespective of climate change.
• Some of the changes to buildings will save energy and reduce CO2 emissions.

This paper reviews the potential health consequences of changes in climate that affect indoor environments, with an emphasis on residential environments in the U.S. and Europe. These changes in climate, include increases in the frequency and severity of heat waves, severe storms coupled with sea level rise, and wildfires, plus increases in urban airborne ozone. The potential for adverse health effects is substantial. Examples of projected effects include a doubling of heat-related deaths, increased hospitalizations for asthma, pneumonia, and cardiovascular effects during wildfires, and increased mortality and hospitalizations associated with ozone. The associated adverse exposures occur, to a significant extent, indoors. The adverse health effects will be substantially mediated by features of buildings, particularly of homes where people, particularly those most susceptible, spend the largest amount of time. Changes to buildings, or to building operations, are identified that could reduce the projected adverse health effects of climate change. Examples include improved roof insulation, roof coatings that reflect more solar energy, and more air conditioning to reduce indoor overheating. Improved particle filtration systems could reduce the health effects of particles from wildfires. Some of these measures will also reduce building energy use and the associated emissions of greenhouse gases. Most of these measures would improve health irrespective of climate change. Improvements in building energy efficiency in order to mitigate climate change, has to potential to either improve or worsen indoor environmental quality and health.