Seal Your Windows for Winter: Simple Methods to Reduce Heat Loss

With energy costs on the rise, sealing your windows for winter can be a great way to save money. Windows are responsible for 30 to 40 percent of a home’s heat loss. Unfortunately, replacement windows can be too expensive for most homeowners. Here are some simple methods to reduce the heat lost through your existing windows and save on your heating bills this winter.

Find Your Leaks

The first thing you need to do is find where the air is leaking out of your house. The easiest way to do this is with a lit stick of incense or a piece of thread. This method works best on a cold and windy day. Turn on all of the exhaust fans, furnace, and the dryer to increase the difference of air pressure inside the house. You should now be able to see any drafts by watching the smoke from the incense or the trail of thread. Mark all the air leaks you find so you know which areas need to be fixed.

Caulk

Caulking is the least expensive way to seal leaks around your windows. Apply caulk on the inside of the non-moving parts on your windows and doors. For windows, apply caulking to the area between the frame and the sash and where the window frame meets the walls. Exterior caulking is also available, but will do more to weatherproof the home than to reduce energy costs.

Weatherstripping

Weatherstripping should generally be applied wherever surfaces move or slide together. Different types of windows or doors require different types of weatherstripping. Sliding windows and glass doors usually require angled weatherstripping material. Some models come pre-installed with weatherstripping, so use a similar type when replacing it.

Use tubular weatherstripping to seal double-hung and vertically sliding windows. Apply stripping to the area in the middle of the window where the two sashes meet and in any gaps between the sash and window frame. Windows that swing open like an awning must be weatherstripped as if you were stripping a door. Attach the weatherstripping on all sides of the window opening, including the hinged side. When the window closes, it will form a seal against the weatherstripping to prevent any air from escaping.

Plastic Film

Plastic film can also help insulate windows and seal off air leaks. Be careful with film applied to the outside of windows if you live in a cold climate. The plastic film may frost over and cause problems with excessive moisture or block the visibility of your windows. Film can be placed on the inside of windows instead, but test the glue first to make sure it won’t damage the surface of your window or the surrounding paint.