Most Maine homes have hidden gaps where indoor air escapes and unwanted outdoor air gets in. That air leakage makes your home harder to heat and cool, more expensive to run, and less comfortable to live in. Similar penetrations can also introduce basement and crawlspace air that’s been contaminated by moisture, radon, and unpleasant smells into your living spaces.
Evergreen Home Performance is a local insulation and air sealing company helping homeowners throughout Portland, Rockland and the surrounding Southern and Coastal Maine areas fix these problems at their source. Air sealing is an essential part of home insulation upgrades and a cost-effective energy efficiency improvement.
- Eligible for up to $8,000 in Efficiency Maine rebates and $1,200 in federal tax credits
- Reduce drafts, improve home comfort
- BPI-certified experts using building science-backed solutions
Why Air Sealing Matters
- Stay warmer in winter, cooler in summer
- Eliminate uncomfortable drafts
- Lower your energy bills
- Improve indoor air quality
Combined with insulation, air sealing creates a powerful barrier between the living spaces in your home and the outdoors.
In addition to energy waste, leaky homes often pull in air from crawlspaces, basements, attics, and wall cavities—along with dust, mold spores, radon, and other pollutants. Sealing leaks gives you more control over your indoor air quality and along with proper ventilation can create a healthier, safer environment for your family.
How We Find the Leaks: Blower Door Testing & Thermal Cameras
Many times newer homes, including really nice ones built before Maine building codes adopted a blower door testing standard, are leaky due to confusion about roof venting and side attics. If you have a newer home and the floor over the garage is cold or pipes freeze in the master bathroom, you could have an air sealing problem that can be diagnosed with a blower door test.
Blower door testing and thermal imaging cameras show us exactly where the air is escaping. We use this building science technology during our energy audits so we can seal the right spots for real results. We then run a blower test again after work is completed to confirm the difference your upgrades made!
Evergreen – The Leading Air Sealing & Insulation Company Near You
- More than 4,500 Maine homes improved since 2006
- More BPI-certified professionals than any other Maine contractor
- Over 15,000 home energy audits completed
- More Efficiency Maine insulation rebates secured for customers than any other contractor in 2024
Attic Air Sealing
Attic air sealing helps slow the stack effect, where warm air escapes out of the top of your home and cold air is pulled in from your basement or crawl space to replace it.
Common areas we air seal in Maine attics include:
- Attic hatches and access doors
- Chimney chases
- Side attics (particularly in Cape Cod-style homes of all ages)
- Lighting fixtures, fans, and vent penetrations
- Plumbing and wiring penetrations
- Wall top plates and framing joints
After air sealing, we blow in cellulose insulation for comprehensive attic protection.
Basement & Crawlspace Air Sealing
Your basement or crawlspace is another major source of air infiltration and leaks in your home. In these areas, we often use some combination of rigid foam board and foam gun insulation, which is both an insulator and an air sealant, giving you maximum protection as well as moisture resistance.
Common areas we air seal in Maine basements include:
- Rim joists
- Foundation walls
- Bulkhead doors and access hatches
- Chimney chases and other floor penetrations
- Gaps around pipes, wires, and vents
Air sealing and insulation is just one component of our basement waterproofing services. When combined, these solutions not only stop air leaks but also protect your basement from moisture and mold.
Airtight & Healthy: Why Ventilation Matters
As we reduce leaks and block outdoor pollutants with air sealing, we also make sure your home has enough airflow and proper ventilation. Without it, moisture and everyday pollutants originating inside your home—from cooking, showering, or just breathing—can build up.
This additional step ensures your Maine home is not just efficient—but safe, healthy, and comfortable too.
Save On Air Sealing with Efficiency Maine Rebates & Other Incentives
We helped more Mainers qualify for Efficiency Maine insulation and air sealing rebates than any other contractor in 2024!
- Up to $8,000 in Efficiency Maine rebates
- Up to $1,200 in federal tax credits for insulation and air sealing
- Financing with payments as low as $50/month through Efficiency Maine Green Bank and NEIF
During your free consult, we’ll tell you all about available Maine energy efficiency loans, tax credits, and rebates, helping you maximize your savings.
