Air sealing is one of the most critical features of an energy efficient home.
To prevent air leakage, it is best to seal the building envelope during construction prior to installation of
the drywall. A “blower door” test is a good way to
identify air leakage paths so that they can be sealed using an appropriate material.
There are many products available for air sealing including caulks, foams, weatherstripping, gaskets, and door sweeps.
What Is Air Sealing?
Air sealing is the systematic finding and sealing of air leakage points throughout your home, from the attic to the walls to the basement and/or crawlspace. Here is a brief breakdown of the process for the various parts of your home.
1. Attic Air Sealing
Lights, Fans, Plumbing Stacks, Chimneys, etc. - Any hole in your ceiling is called a thermal bypass, or air leak. We spray foam around most of these, including around light fixtures, bathroom fans, open wall cavities, and plumbing stacks. Other items like chimneys and recessed lights require special methods. There are a large number of items that require a professional to find and correct properly.
2. Wall Air Sealing
Insulation and/or Outlet Sealing – The simplest item on walls is to put foam backers behind the outlet covers and child proof plugs to stop air coming out the outlet holes. The harder part is insulating walls. If you have a newish home, about 1970 or later, your walls are probably insulated. If you have an older home, especially before 1965, your walls are probably empty. Empty walls generally account for 20-40% of air leakage, and are the best area to reduce leakage. We can insulate most walls and drastically reduce both the air leakage and energy bills of your older home.
3. Basement/Crawlspace Air Sealing
There is a lot of leakage in the basement, and since it is accessible in most homes, it is a priority for us.
Why Do You Need To Air Seal?