How To Insulate Attic Stairs | A Step-By-Step Process

Heat loss sources within the home are typically manageable once you’ve identified them. When it comes to your attic, you can have its floor and walls insulated.

However, what a lot of new homeowners don’t know is that the drop-down stairs to their attic can also be an easy escape route for that precious warmth they wish to keep trapped inside.

This happens because attic stairs are typically separated from the rest of your home only by a thin sheet of wood, allowing heat to escape easily. So today, we’re going to be telling you how to insulate attic stairs.

We’ll be covering two methods of doing this: building a DIY attic door foam cover or using an attic stair insulation cover.

Method 1: DIY Foam Box

This is the most common method of insulating attic stairs. It’s a little time-consuming but done right; it can prevent significant heat loss. You can always enlist the help of a professional to build it for you, but it’s not that difficult to do on your own.

What You’ll Need

  • Roll foam tape weather stripping – ¾” x 17’ (two)
  • Rigid foam board sheet – ¾” x 4’ x 8’ (one)
  • Roll foil duct tape – 2” x 30’ (one)
  • Caulking tube (one)
  • Utility knife

Remember, regular duct tape won’t cut it as it’s not as strong as foil duct tape. Also, all of these materials together won’t cost you more than $30-$40. Who knew preventing heat loss through the attic door was so cheap?

How to Insulate Attic Stairs with a DIY Foam Box?

If you have everything you need, now we can start building your foam box attic door cover.

Step 1: Apply weather stripping

First, check that your folding attic stairs are able to close securely and tightly. Then, take your self-adhesive foam weather stripping and apply it all around the perimeter of where the frame and the door meet. Do not apply the weather stripping to the hinge end.

Step 2: Take measurements

The first measurement you need to take is of the dimensions of the opening (not the frame!). Then, note down the height to which the stairs protrude above the attic floor.

Step 3: Cut out foam sides of the box

Using your utility knife, cut out strips from your sheet of foam. These strips will make up the box cover’s sides. The strips should measure 1-2 inches wider than the extension of the stairs above the attic floor.

Step 4: Start building the box

Using a framing square to guide you, cut the foam strips to lengths, and form the box. Secure the corners using foil tape. Now take your caulking and apply a bead to the corner joints–this will create a stronger seal.

Step 5: More weather stripping

Once the box’s top edge has been solidified, attach some more foam tape weather stripping to it. Now cut up some more foam fitting the exterior dimensions of the box. This will make up the lid.

Step 6: Secure the lid

Using your foil tape, attach the foam lid to the top of the box. Secure the edges with more foil tape.

Step 7: Install the box

Before you can do this, clean the area around the stairs as this will allow the tape to stick more securely. Place the box over the opening, then attach it to the floor using foil paper. Once again, use caulking for a more secure seal.

And that’s it! You’re done. Now, if that all seems like too much work for you, you can go ahead and buy yourself a premade zippered cover for your attic door. The instructions on how to use one of those are detailed below.

Method 2: Using A Premade Zippered Attic Cover

Does the DIY cover seem like too much work for you? Good thing zippered attic covers exist for you to purchase. However, note that these can be quite expensive, so if you’re on a budget, we’d still recommend the DIY method. If not, read on.

What You’ll Need

  • Measuring tape
  • Staple gun
  • Caulk
  • Caulking gun

How to Install Your Zippered Attic Cover?

Got everything you need? Here’s our step-by-step guide to finding and installing your new zippered attic cover.

Step 1: Take measurements

Get your measuring tape and climb into your attic. Once you’re in there, close the staircase. Now, measure the height of the stairs (in their folded position) from the floor of the attic. Next, take measurements for the width and length of the opening of the stairs. Now go find yourself a cover that fits these dimensions!

Step 2: Break in the zippered cover

Get back into your attic and close the stairs. Take your new zippered cover and place it carefully over the opening of the stairs. The zipper endings should align with the stairs’ hinges.

Step 3: Install the cover

The flange must now be laid down flat all around the stair opening. Once this is done, take your staple gun and staple it all the way around the frame of the stairs. You should be inserting a staple at 3-inch intervals to prevent gaps. Next, pressing the flange flat against the wood, take your caulking tube, and spread a caulk bead all the way around.

Step 4: Finish up

To engage your attic stairs, open the zipper cover. Zip it closed as you’re going down the stairs.


Even the best attic ladders can contribute to heat loss in your home, so it’s important to seal that up as soon as you can if you want to continue enjoying the warmth. We hope our DIY method has helped you learn how to insulate attic stairs; if not, pre-made covers are always a good place to turn to.

Good luck, and stay warm!

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