How to Insulate My Garage

“Why should I insulate my garage?”

Insulating the walls, ceiling, and doors of your garage can help reduce the energy consumption for your entire home.

It will keep the garage cooler in summer, and warmer in winter, and reduce outside noise. Insulation will also help protect the interior of your home from harmful fumes emitted by cars, gasoline, and other chemicals stored there. It is an easy project that can reap many benefits.

Once homeowners realize they need to – or want to – insulate their garage, this is one of the first questions they ask. Let’s start with the garage door.

These are rigid insulation, like foam board, can be cut to size and inserted into the recesses between the frames

Reflective insulation or foam board can be attached with adhesive or tape to the inside of the garage door.

The tools and materials you need to insulate your garage are few. Mainly, you need:

• The insulation itself, whether in board panels or rolls, dependent upon the application
• A way to fasten the insulation to the door: tape or adhesive
• A utility knife to cut insulation to size

Garage door insulation kits are also available.

Garage Insulation: How To

Insulating your garage is easiest prior to the installation of drywall when the framing is still exposed.

1. The first step is to air-seal the walls, blocking gaps, cracks, or holes. 
2. Seal around outlets and switches with silicone caulk. Run silicone caulk around the garage where the framing meets the floor to seal out fumes.
3. Once air-sealed, roll out fiberglass insulation, also called batt and blanket insulation, and attach it to the walls according to manufacturer directions. For the wall shared by the living space, install the fiberglass insulation with the vapor retarder called kraft facing with the paper side facing the wall and the fuzzy side facing you.
4. For the rest of the walls, install the insulation with the kraft facing with the paper side facing you so that it will butt up against the drywall once the garage is finished off. Roll or blow insulation into the garage attic or ceiling.

Alternative types of garage insulation can be blown in or sprayed on. Sheep wool insulation offers an environmentally friendly, natural option.