Air Sealing a New Home
According to the Department of Energy, 40% of heat loss in a building is due to air leakage. If this is not reason enough to air seal a new home, let’s consider another idea: air leakage is air movement. Air movement carries moisture. Moisture fuels mold growth. So if you stop the air movement (the air leakage), you greatly reduce the chance for mold growth in the walls of your home.
How to Air Seal
There are many avenues you can take when considering air sealing a home. There are a few low-cost things you can do to start air sealing your home. A simple step like caulking double studs and top and bottom wall plates is a great place to start. Great skill nor expensive tools are necessary to complete this project: all that is needed is a caulking gun and a step ladder.

Keep in mind that it can take several cases of caulk to air seal a home depending on the size and how the house was framed. This is a project that anyone can do, including a prospective home buyer who is looking to save some cash. For great results, you must pay great attention to detail. This video has great ideas as to how to air seal your walls:
Window Sealing
The next step in this project would be to seal all protrusions in the exterior walls. This includes electrical boxes, plumbing, and AC lines. Any other protrusions should be sealed up and a great way to do this is with canned spray foam you can find at your local hardware store or lumber yard.
Most quality windows are sealed very well. However, when installed in a rough opening of the wall there can be a gap up to an inch. This area also needs to be air sealed. It is important to be careful when sealing these areas up because the window manufacturers have specifications as to how it should be done, and it varies from manufacturer to manufacturer. You can seal these gaps with caulking or canned spray foam.
When using canned spray foam around windows and doors, it is extremely important to utilize the proper type. There are two kinds of canned spray foam: minimal expanding (or door and window) and regular expanding. When working with windows you definitely want to use the minimal expanding canned spray foam. Using the regular expanding spray foam can cause the window frame to bow which leads to wedging the window shut, damaging it. Another important tip when using canned spray foam: be patient. Use a small amount and allow it to expand. Make several short passes and wait between applications to allow it to expand fully. Failing to do so results in using too much product and having to trim it off, resulting in wasted material.
Ceiling Sealing
The best time to seal the ceiling is after the drywall is hung. Once again, any protrusions through the ceiling needs to be air sealed (including electrical boxes, wiring, can lights, duct work, etc.). Also don’t forget bulk head areas over cabinets or chases. Canned spray foam can work well for most of these areas. It might also be required to use a foam board to cover the protruding area and then to seal around it.
For more air sealing tips, you can download this book from Green Builder Magazine.
Spray foam insulation is also an air seal. Choosing Iowa Spray Foam to install open or closed cell spray foam in your new home can seal up many of these areas mentioned in this blog and more. Open or closed cell spray foam insulation finds all of the cracks and gaps the wall or ceiling areas may have. Give Iowa Spray Foam a call and let us show you how to stop up to 40% of the heat loss in your new home.