How to Insulate a Hollow Interior Door

Lanh Ma

A hollow door, also known as a hollow-core door, is lighter than a solid door and less expensive as well. However, it lacks the insulating qualities of a solid door, and you may find that you can feel drafts very strongly if the door leads from a cold area inside your home to a warmer area. While you cannot inject spray foam into the door itself, you can use rigid foam insulation to cover the door and warm your home.

Step 1

Measure the height and the width of the hollow-core door.

Step 2

Cut a segment of rigid foam insulation that matches the measurements of the hollow-core door, using a craft knife. If you have a large door, you may need more than one piece of foam butted up next to each other.

Step 3

Apply a thin coat of epoxy adhesive to the side of the door where the insulation will be affixed. Choose the side of the door that you see the least.

Step 4

Press the insulation to the door, holding it in place for several seconds until the epoxy holds.

Step 5

Allow the epoxy to cure for 24 hours.