How to Insulate a Garage Door

What You'll Need
Polyurethane foam sheets
Tape measure
Utility knife
Putty knife
Aluminum foil tape
Weather stripping

Most people don’t think of a garage door as a source of heat loss. Even so, if your garage is attached to your house you could still be losing heat through it, and this will ultimately cost you money. What is the best way to stop the heat loss? The ideal solution is to insulate your garage door. You’ll soon notice the difference in terms of how your house feels and the savings in your energy bills. It’s a simple procedure you can easily undertake yourself.

Step 1 - Measure Your Doors

Your garage door will consist of a number of panels. Measure each one (they should all be the same size, but check carefully anyway) and buy the appropriate number of polyurethane foam sheets required from your local hardware store. They should be at least 1 inch thick to be fully effective.

Step 2 - Fitting the Insulation

Using a utility knife, cut each of the sheets to the exact size of the panels to be filled. Apply glue to one panel then push the cut polyurethane foam sheet into place. You will need to use the putty knife on the edges to ensure you have a tight fit. Press hard against the panels until the polyurethane foam sheet is securely in place against the garage door.

Repeat the procedure for each of the panels until you have foam sheets in all the panels.

Step 3 - Extra Insulation

Cover the edges of each of the polyurethane sheets with aluminum foil tape. This will cover all the gaps and stop any cold air entering. Be thorough and put tape around the edges of all polyurethane sheets.

Step 4 -Weather Stripping

So far, you will have taken precautions to stop heat escaping through the garage door itself, but there will still be a gap at the bottom where the door meets the ground. You can stop heat escaping from here by using weather stripping.

Use enough weather stripping to cover the entire door. There will be a tear-off strip on one side covering a layer of adhesive. Remove the strip and push the weather stripping firmly in place at the bottom of the door so it closes the gap between the garage door and the floor, but still allows the door to open easily.

To make sure the weather stripping stays in place, use a hammer and nails to keep it firm and secure. Place a nail every 6 inches along the bottom panel of the garage door. Screws can be used on metal doors that are resistant to nails.

If you have double garage doors that comes together to close, use weather stripping from the top to the bottom of the door that closes first to promote a good seal between the two doors. Again, nail or screw into place to keep it firm.

Step 5 - Testing the Door

Once you’ve finished, you will need to test the garage door to make sure there are no drafts. Close the door and run your hand around the openings. You won’t eliminate every single draft, but you should find that there will be hardly any cold air coming through the garage doors.