Insulating a Crawl Space/Attic Door for Improved Energy Efficiency

Alicia W
by Alicia W
9 Materials
1 Hour

I love our nice big closet in our bedroom but I don’t love the uninsulated access door to our crawl space which is in the closet. It gets a little frigid in there during winter mornings.

Materials Needed:

Foam panels (3/4"x13-5/8"x48")

Utility knife

Painter's tape

#10 washer & wood screws


Putty knife

3M Heavy Duty duct tape


Rubber tubing

Door sweep

Access door to crawl space

This is the access door to our crawl space which runs along the length of our bathroom. The access door is in our closet which is fine except the fact that the crawl space has very little insulation and neither does the door.

Flame test: use a match to check if there is a draft

As you can see, using the ”flame test”, the door is a little crooked which leaves a gap at the top and the bottom which allows cold air to flow into our closet.

Remove the old stick-on insulation using a putty knife for a clean starting point

My husband and I have made numerous attempts to quickly put up insulation but it always ended up not working.

I decided enough was enough and I was going to insulate it correctly.

1. Remove old insulation

I began by removing the old stick-on insulation using a putty knife.

Mark where the door frame and door make contact

2. Mark where the door frame meets the door

Then I went inside the crawl space and closed the door. Using a pencil I drew onto the door where the door frame came in contact with the door (Red line)

Foam insulation panels

I purchased this pack of foam panels. They are 3/4”x13-5/8”x48” and there are 6 in a pack. I only used 3 for my door.

Measuring the door

3. Measure the door width

I began by measuring the width of the door.

Preparing the foam panels

4. Prepare the panels

A. I marked one foam panel

B. Drew a straight line

C. Cut using a utility knife

Use painter's tape to hold the panels against the door

5. Attach the insulation panels

To hold the panels in place, I used painter’s tape and taped the panel to the door.

Attaching the insulation panels

A. I drilled a pilot hole

B. Using a #10 washer & wood screw

C & D. I attached the panel to the door making the screw snug but not too tight.

I used a washer to assure that the screw didn’t got completely through the foam.

Once the door was screwed in place, I removed the painter’s tape.

Insulate the door

6. Insulate the door handle

For the inside door handle:

A & B. I measured and cut pieces to fit around the handle

C. I used white 3M Heavy Duty duct tape to hold the pieces in place

D. Then I added more duct tape to assure that everything holds

I continued to add foam panels working my way down the door. Where sections of foam came together, I taped the seam with duct tape. The red circles indicate where I attached screws to the door.

Caulk the edges of the panels

7. Caulk

Once all of the panels were in place, I caulked around the edges of the panels.

Rubber window seal

8. Add rubber tubing

While the caulk dried,

A & B. I added rubber tubing around the edge of the door

C. It is adhesive and the back peels right off

D. I attached it around the inside edge of the door

Add a door sweep

9. Add a door sweep

To finish,

A. I used a door sweep

B. This is also adhesive and the backing peels off

C. I applied the sweep to the bottom of the door

How to insulate a crawl space

Insulating a Crawl Space/Attic Door for Improved Energy Efficiency

Now my door is completely sealed and as you can see by the “flame test”, no air is leaking through.

I’m ready for you, Old Man Winter!

More Clever Ideas to Add Warmth to Your Home

Looking for more ways to improve insulation and reduce heating expenses? Check out our post on heating your home on a budget for a variety of DIY solutions.

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3 of 20 questions
  • Carrie Berg Carrie Berg on Feb 06, 2019

    My front door does not match up to the frame very well. And I can see daylight from every side. I'm a renter, so I'm limited to some options. Is it even possible to do something like this to my front door and have it look nice? I have tried all store products and nothing stays for very long.

  • Nancy Nancy on Feb 07, 2019

    We have a bilco door...horrible...not insulated...any ideas.?

  • Frederick Frederick on Oct 19, 2021

    What is the best, most economical and easiest way to insulate a 48” Deep x 30’ Wide x 70’ Long house crawl space. The entire floor in the crawl is smooth concrete.

Join the conversation
3 of 81 comments
  • Donna Donna on Oct 16, 2019

    In your case, I am wondering whether it would have been faster, and easier to cover the inside the closet walls with the foam panels to insulate the walls, rather

    than the door. I am thinking that there must be some kind of removable glue, such as post note pad type glue to attach the panels to the walls and ceiling, of your closet and then tape the panel joints.

    • Lisa West Lisa West on Oct 21, 2019

      The air was and is coming from the door opening. That's what she wanted to stop to hold in the heat in her closet and bed room. Now for extra insulation I would do that around the bathroom walls to help keep the bathroom from getting cold. I feel there is nothing more uncomfortable is a bathroom. We use the bathroom more then what we think. Beside going potty we shower brush our teeth. S ok me use the bathroom to do make up hair. Men use to shave and do their hair if they have hair. Wash hands and so on. It amazing how much we really are in the bathroom. For me I hide in here from people when I need a few min of quiet lol.

  • Rick Rick on Oct 14, 2020

    I would only suggest using the chaulk alone to hold the foam panels on instead of screwing them on.