Your home can experience air leaks when outside air enters through small cracks or openings through your windows. During the winter, cold air can enter your home and warm air will escape, and vice versa in the summer. When you have air leaks in your windows, you will likely notice that rooms are drafty, or your energy bill is higher than usual. Find out how to spot and air leak and what to do about it.
Three Ways to Find an Air Leak
1. Check for Light and Feel for Drafts
The easiest way to check for an air leak is to look and feel around your windows. First, walk around the outside of your house and see if there are any obvious cracks or holes where the building materials from your siding and window meet. During the day, go inside, turn off the lights in your home, and look to see if there is daylight coming through on the sides or at the bottom of your window. On a cold day, hold your hands an inch away from the window frame and feel for any drafts.
2. Conduct a Flame Test with a Candle
If you can’t see or feel air leaks, then conduct a flame test with a candle. Light the candle and trace the outline of your window. If the flame and smoke pull in one direction, then you have found an air leak. If it isn’t clear whether the smoke is moving or not, have someone stand outside the window with a hairdryer, again tracing the outline of the window. If the candle flickers, then the window is allowing air through.
3. Rent a Thermal Camera
If you are having a hard time finding air leaks even with the smoke test, then you can also rent a thermal camera from your local hardware store. The thermal camera can even help you detect energy leaks in your ductwork and roof as well as missing insulation all around your house.
How to Repair Air Leaks
Once you have identified the location, fixing small air leaks is a DIY project that is low cost and won’t take up your entire weekend. However, patching an air leak is a temporary solution. Caulking and weather stripping will stop an air leak, but once you have a leak the window is no longer energy-efficient and you should consider replacement.
To repair an air leak you will need:
- Caulk and a caulking gun
- Putty knife
To seal air leaks in the window frame and grilles:
- Clean all areas to be caulked with soap and water, removing paint or old caulk with the putty knife. Wait for the area to dry so you do not seal in the moisture.
- Apply caulk to the areas to be sealed at a forty-five-degree angle in a continuous stream. Make sure the caulk sticks to both sides of the seam.
- If caulk leaks out of the crack, push it back in with the putty knife.
- If the caulk shrinks, reapply in a smooth line that seals the crack completely.
To seal air leaks between the lower window rail and the window sill:
- Clean the area where you will apply the weatherstripping with soap and water and let it dry.
- Measure the window width and cut the weatherstripping to size.
- Apply weatherstripping to both surfaces and ensure that the material compresses to form a seal when the window is shut.
After you have repaired the air leaks, check again using the tips above to make sure the window is fully sealed.
When to Call a Window Professional
If the issue is more significant than a small air leak that can be sealed with caulk or remediated with weather stripping, then you may need to replace your windows. Contact a professional window replacement company if your window frames are rotting or moldy, your windows have become difficult to open or close, or you see condensation on the inside of single pane or in between the glass on double pane windows. Remember, caulking and weather stripping is a temporary solution. To maintain a good seal on your home, your windows will eventually need to be replaced.
If you have noticed any of these signs or your windows are over ten years old, they could be due for a replacement. Schedule a free, no-pressure consultation with one of Brothers window experts to find the best option for your home.