Building retrofit projects and green materials boost energy efficiency, but they may also produce some unwanted results – health problems for the building’s occupants.
According to a report by the Institute of Medicine, an independent nonprofit that provides unbiased, authoritative health advice, some green projects and materials can limit or alter air flow in buildings. This can then concentrate indoor pollutants, such as chemical emissions and tobacco smoke, and affect IAQ. Climate change can amplify existing indoor environmental problems and introduce new ones, according to researchers.
Other potential sources of pollutants and irritants include:
- Indoor combustion emissions from cooking, backup power generators, and space heaters
- Emissions from materials, including VOCs and SVOCs (semivolatile organic compounds)
- Carbon dioxide (the main source of which is building occupants exhaling)
- Outdoor pollutants that enter the building through ventilation, such as ozone, pollen, and post-flood algal blooms
- Indoor dampness
- Poor ventilation
- Excessive temperatures
“Efforts to save energy by improving building performance need to be accompanied by strong caution with respect to changing building ventilation rates,” the report’s authors wrote.
“Energy is required to condition the temperature and humidity of ventilation air, so individuals and organizations may seek to save energy by reducing the rate of ventilation of indoor spaces. … A lower building ventilation rate will tend to provide enhanced protection against some pollutants from outdoors, but reduced ventilation rates tend to cause concentrations of pollutants that originate primarily from indoor sources to increase.”