How to Insulate the Floor Above a Crawl Space

Insulating the floor above the crawl space ensures that you are not loosing heat through your floors during the winter months. Installing some basic fiberglass insulation should greatly reduce any heat loss, you should recoup the initial expense in a couple of years depending on the climate. Installing fiberglass insulation is the same as installing it in any other location, except for the placement of the paper moisture barrier.

Be sure when working with fiberglass insulation that you are wearing the proper safety equipment. Safety goggles, a face mask, and work gloves are a must, but so are long sleeves and long pants to prevent the fiberglass insulation from irritating your skin. Be careful when installing fiberglass insulation in the crawl space; because you will be underneath it during installation, it can easily drop on you, scratching your face.

Step 1: If you store objects in the crawl space, remove them now to give you a clear area to work in. You may also want to clear away any spider webs or other obstructions that may distract you during the installation process.

Step 2: Measure the depth of the floor joist as well as the space between each joist. Purchase fiberglass insulation with the paper back that is the exact width of the floor joists. You should also be able to fit it between the floor joists without crushing the insulation: compacting insulation lessens its insulating properties.

Step 3: Place the fiberglass insulation between the joists, with the paper backing facing towards the floor the joists are supporting.

Step 4: Use a wire insulation hanger to hold the fiberglass insulation in place, putting one every 18 inches along the joists. The insulation hanger should bend slightly inwards to hold the insulation up and into the cavity between the joists..

Step 5: Continue installing fiberglass insulation and insulation hangers until one cavity is completely filled. Cut the excess fiberglass insulation using a utility blade.

Step 6: Install insulation in the next cavity, continuing until all of the cavities are filled with insulation.