How to Seal Basement Air Leaks

Make your basement more efficient with caulk and foam.

Basement air leaks need to be taken care of as soon as possible, because this type of leak in a home can end up costing you quite a bit of extra money in unnecessary heating and cooling costs. Air leaks can also make way for other problems, such as structural damage, foundation issues and water leaks. Your best bet is to take care of the problem and seal the basement air leaks with the most effective methods.

Things You'll Need

• Caulking gun
• Silicone caulk
• High-temperature caulk
• Expanding spray foam

Instructions

1. Use the right type of sealing materials to seal basement air leaks. You will need a caulking gun, silicone caulk, high-temperature caulk and expanding spray foam.

2. Find the rim joists on the ceiling of your basement. The rim joists are at the very end of the joists that make up the floor cavities for the floor above the basement ceiling.

3. Load the silicone caulk into your caulking gun and apply it to the top and bottom of the rim joist. This is a common area for air leaks.

4. Seal any basement air leaks in the rim joists that are greater than 1/4 inch and leaks in the area between your foundation and the sill plate with expanding spray foam.

5. Apply expanding spray foam to any areas in the basement ceiling or walls that have a space for things like pipes, vents or electrical wires.

6. Remove the silicone caulk from your caulking gun and load the high-temperature caulk. Use it to seal the area where the furnace flue goes into the basement wall.

References

• Energy Star: Sealing Air Leaks --- Basement