Reducing the amount of air that leaks in and out of your home can be a cost-effective way to reduce heating costs and improve comfort. Some air sealing measures like caulking and weather stripping can be installed as do-it-yourself projects. But many air sealing projects are best completed by a professional. A professional energy assessment can help to prioritize air sealing efforts.
Air sealing reduces drafts and heat loss by eliminating gaps in the building envelope and around the chimney, plumbing penetrations, and recessed lights. Registered Vendors use a variety of materials, including caulk, spray foam, metal flashing, weather stripping, and rigid foam. Some materials are more suitable than others for specific locations or trouble spots. For example, fire-rated caulk and metal flashing are used in high-temperature air sealing situations like around the chimney.
Air sealing can be difficult to visualize, but symptoms include drafty rooms, musty smells traveling from the basement, and ice dams. Spider webs are often indicators of where there is airflow in basements and crawl spaces.
The Department of Energy graphic below has a useful cross-section diagram illustrating the most common air leakage spots.
The best way to learn where your home might benefit from air sealing is to consult with a Registered Vendor. They’ll use diagnostic equipment like a blower door to assess the relative “leakiness” of your home, locate the leaks with a smoke pencil or a thermal camera, and recommend ways to improve comfort and efficiency.
|$||1,000||Typical air sealing project|
|–||$||400||Incentive from Efficiency Maine|
|$||600||Net installation cost|
3 year simple payback
$4,000 savings over 20 years.
Note: Actual savings may vary.
- Comfort – Air sealing reduces drafts, which can make rooms warmer in the winter and cooler in the summer.
- Reduced Heating Costs – Reducing the amount of air that leaks in and out of your home can be a cost-effective way to reduce heating costs.
- Durability – Air sealing reduces movement of moisture in the home and helps maintain the integrity of your home.
- Quick Payback – Air sealing is one of the most affordable home performance projects, and many homeowners recoup their investment within a year.
- Incentives and Financing – Efficiency Maine offers rebates and loans on qualifying air sealing projects.
- Lower Environmental Impact – Reduce the carbon footprint of your home by reducing heating and cooling demand.
- Trapped Moisture – While air sealing can minimize outside air coming into your home, it can also trap moisture indoors. Make sure to address moisture problems before, or as part of, an air-sealing project.
- Inadequate Ventilation – In extreme cases, air sealing can make homes too tight, requiring a mechanical ventilation system and/or make-up air for heating systems. Air sealing should be done in conjunction with blower door testing.