To install insulation in a garage ceiling, first choose the type of insulation that will work best in the space. Each insulation type offers different benefits and requires a different procedure for installation.
Insulation types include roll, batting, blown-in and spray foam insulation.
Step 1: Choose the R-value and size
The R-value is determined based on area requirements, and ceilings and attics commonly use R-30 and R-38 batts. Sizes are determined by the distance between the wall studs.
Step 2: Open the packaging
Take care to avoid cutting the facing and cut lengthwise along the side panel.
Step 3: Install the batting
Push the batts into the open areas, taking special care around corners and edges to ensure full coverage. Face the vapor retarder toward the interior space, unless otherwise stated by local building codes.
Step 4: Staple the batts in place
Friction can hold the batts in place, but to staple faced batts, staple the flanges to the inside of the joists. Avoid gaps and ensure that the facing is not stretched too tightly.
Step 5: Cut to fit
Do not compress the insulation to fit into smaller spaces, which changes the insulation's R-value. Instead, cut the unfaced side with a sharp utility knife about an inch longer than necessary. To join multiple batts, ensure both pieces fit snugly together and cover the entire space without gaps.
An insulated garage ceiling increases the energy efficiency of the entire home, and it is worth the time and effort to insulate the space.