For many people, having an attached garage is a major convenience that allows them to keep their vehicles out of the rain, snow and hot summer temperatures. Garages also act as a storage and work area for many people. Some properties even house components of the home’s mechanical system in the garage.
While attached garages do provide many benefits for homeowners and renters, they can also be a source of indoor air quality issues within the rest of the home and even cause safety concerns in some circumstances. A major reason for this is any gases, vapors, fumes and particulates that are airborne in the garage can in many circumstances enter the home.
This can happen in a number of ways. For example, if the garage is positively pressured as compared to the house, the garage air will try to make it into the attached home. This can occur through an improperly sealed door leading into the home, through the HVAC system if it is located in the garage or if there are vents or leaking duct work in the area. It can also occur if there are unsealed, cracked or damaged garage walls and ceilings. Even opening the door to the garage can allow pollutants to enter.
One of the major concerns is carbon monoxide (CO). Carbon monoxide is an odorless, colorless gas, which can cause sudden illness and death. It is produced any time a fossil fuel is burned so a vehicle running in the garage or a clothes dryer, hot water heater or furnace in the garage that is powered by gas and is not properly vented could create unhealthy levels of carbon monoxide.
Another common issue is the storage and use of various fuels, paints, cleaning compounds, fertilizers, pesticides and other chemicals. While being used, or if not properly stored, these materials can off-gas volatile organic compounds (VOCs) and other chemical compounds into the air that could make their way into the home.
Garages that suffer from leaks or have had water damage or elevated humidity levels can even be the source of mold growth. Mold spores and fragments can easily become airborne.
Fortunately, there are steps people can take to help prevent an attached garage from negatively impacting their indoor air quality. They include the following:
• Make sure the door leading into the garage is properly sealed and is kept shut.
• Be sure the home has working carbon monoxide sensors and consider putting one in the garage.
• Do not run a vehicle or other gas powered engine in the garage. Once a vehicle is started drive it out of the garage, never letting it idle in the garage.
• Seal all opening in the garage walls and ceilings.
• If the garage is used as a workshop consider installing an exhaust fan. Also have the home checked to make sure it is positively pressured compared to the garage.
• Be sure all chemicals and fuels are stored properly and consider using an outdoor storage shed that is properly ventilated to house these materials.
