How Do You Make a Basement Window Water and Air Tight?

Basement WindowsIt’s important for homeowners to learn how to make a basement window water and air tight. A basement window that allows cold air to come in or warm air to leak out can cause a homeowner to pay high energy bills. When moisture leaks through a basement window, it can lead to mold growth and poor indoor air quality. However, windows that are water and air tight are energy efficient, according to Energy Star. They keep the cool air in during the summertime and the cold air out during the winter. Take a look at what a homeowner can do to make a basement window both water and air tight.

Examining the Condition of a Window

In some cases, it’s obvious when a window is allowing air or water to enter your basement. You may see moisture collecting around the edges of the window or you may feel a breeze when you stand next to it. If you aren’t sure about the quality of the insulation on a window, look for cobwebs. Spiders build their webs in windows that have gaps where air is circulating. Chances are, the spiders entered through the gap and catch bugs that come in that way as well. If you don’t see any cobwebs, try lighting a stick of incense and holding it up to the edge of the window. If the smoke starts to blow inward, you know that air is leaking in. When looking for water, press your fingers around the edges of the windows to see if there is any moisture. If you determine that your windows aren’t water or air tight, there are steps you can take to fix the situation.

Steps for Making a Window Water and Air Tight

One of the simplest ways to make a basement window water and air tight is to fortify it with low expansion foam. There are different brands of low expansion foam made especially for windows. You may want to purchase a 12 ounce can of expansion foam or a larger amount. The amount of expansion foam you buy depends on the number of basement windows that need your attention. You can even buy low expansion foam in a particular color such as yellow, cream or white. In some instances, the foam around a window is visible to people in the basement. Some homeowners prefer one color over another. Along with a supply of low expansion foam, you need a durable pair of work gloves, goggles and a utility knife to accomplish this task. Also, you may want to wear old clothes, because spilled foam is difficult, if not impossible, to remove from fabric. Most cans of low expansion foam have a long straw attached to the nozzle so you can aim the foam exactly where you want it. This also helps get the foam into the small, narrow areas around a basement window.

The first step in the process is to look for the space between the wall and the edge of the window frame. This is where moisture and air are coming in. It’s also where warm air from your furnace is escaping during the cold weather months! Read over the instructions on the can of low expansion foam and then stick the straw into the gap in the wall and fill it halfway up. Make sure you go all around the border of a window filling the gap to its halfway point. Then, let the foam dry for 30 minutes or however long the instructions indicate. This layer serves as the first barrier against air and moisture.

Finishing the Insulation Job

After letting the first layer of foam dry, put another layer on top of it all around the window. Even if the first layer allows a little air or water through, the second layer acts as a backup. Allow the second layer to dry. If you find excess globs of dried foam around your window, you can trim them away using a utility knife. Because this is low expansion window foam, it won’t damage the shape of your window frame over time by expanding or contracting in a dramatic way.

Related Resource: How to Install an Egress Window

Finally, making these adjustments to a basement window can help homeowners to save money on their energy bills. Also, it can result in a more comfortable atmosphere in either a finished or unfinished basement. When you learn how to make a basement window water and air tight it can improve the overall value of your home.