Installing Blanket Insulation in Your Attic

Lead Image
What You'll Need
Blanket insulation
Straight edge
Utility knife
Measuring tape
Eye protection
Face mask
Plastic sheeting
Staple gun

Installing blanket insulation in your attic can shave hundreds of dollars off your utility bills. Blanket insulation comes in several styles, from fiberglass to rock wool. You need something that provides enough heat resistance (R-value) for your region and still fits within your budget.

Once you get the right insulation, follow the steps in this article to install it correctly. Even if you don't have much experience with home improvement projects, you can do it — it's easy.

Step 1 — Take Measurements

Measure the dimensions of the attic so you can buy enough insulation to cover the entire attic. Then, measure the space between your joists and add a fraction of an inch. This will ensure a snug fit.

Step 2 — Trim the Insulation

Blanket insulation is very easy to cut, and a utility knife is all you'll need. Use your measurements and follow a straightedge to get a straight cut. Remember to wear your gloves, face protection, and protective glasses to prevent the insulation from getting on your skin, in your lungs, or in your eyes.

Step 3 — Place the Insulation

Start with the long pieces of insulation. Press them between the joists. They should fit easily but be snug. Press down until you feel resistance, making sure the insulation is flat and even. Once the larger pieces are in place, you can fill in the odd spaces with the leftover insulation.

Step 4 — Add a Vapor Barrier

Start in a corner and staple the vapor barrier to the joists. Pull it across the joists, keeping the plastic tight and stapling it in place. Overlap it to create a seal. Continue placing the vapor barrier until the entire area is covered. You now have an attic that is properly sealed off from the elements and won't let heat escape.