How to Insulate Attic Stairs

Drop-down stairs leading up to your home's attic can be a major source of heat loss. Heat will find its way to that opening and straight out of your home, leaving you in the cold and paying for it in more ways than one. There are insulating stair covers you can purchase, but they can be a little expensive. So let's take a look at how you can insulate those attic stairs yourself, stay warm and save a buck or two all at the same time.

Things You'll Need

• Insulating foam boards (amount determined by size of stairs opening)
• Utility knife
• Foam weather stripping or caulk
• Radiant foil tape

Instructions

1. Once in your attic, pull up the stairs so the opening is completely closed. Measure the dimensions of the opening, making sure not to forget the height if your stairs protrude above the floor of your attic. Now cut four lengths of foam to form a box around the opening. Later, when the box is put in place, the width of these cuts becomes the height of your insulation box, so you want them to come about 2 to 3 inches above where stairs end over the floor. Don't tape them to the floor yet, though.

2. Now take the lengths of foam you have cut and attach them to each other with radiant foil tape at the corners, forming a box. The foil tape works best because it does a better job of reflecting heat back into your home, preventing its escape through the attic. Then use your caulk or foam weather stripping to provide a seal on the inside of your insulating box.

3. Apply more weather stripping to one of the long sides of your box on the top. Now cut a new piece of foam according to the measurements of your box and use this for your lid. Attach the lid to the top of your box, and then apply weather stripping to the inside where the lid and box meet to strengthen the seal.

4. Using the foil tape, attach the box to the floor around the opening for the stairs. Make sure of two things when doing this. First, that the floor is completely dry. Moisture can weaken the adhesive properties of the tape and break the seal. Second, clear the floor of dust and debris before affixing the box to the floor. Otherwise you may end up with air bubbles that can also compromise the seal.

5. Now run more radiant foil tape along the outer edges where the box meets your attic floor. Then use caulk to add to that seal on the inside of your box, providing better insulation.

Tips & Warnings

• For a better insulation, you can add caulking to the opening of your lid, just make sure you do not seal it shut so it won't open. Ask someone at your local hardware or home repair store what type of insulating foam is best for your area, climate, and type of home. There are different types, qualities and thicknesses to choose from. Build your foam insulation box after the attic stairs have been installed and sealed from beneath. Always close the lid when leaving your attic.

• Be careful with the utility knife. Do not use too much pressure or you may go through the foam suddenly and cut yourself. Make sure you use a proper utility knife. DO NOT use a knife from your kitchen.