How to insulate a garage

Insulating your garage is an excellent way to make the space more useable, which opens up a range of possibilities, all of which lead to a better and more valuable property.

Whether you want to build a workshop, convert the garage into an additional living space, or just keep your car warm on those chilly winter mornings, properly insulating the garage is a logical first step.

In this article, we offer a detailed guide on how to insulate your garage, including what supplies you’ll need, the steps to take and how to get professional assistance if you need it.

For best results, we always recommend hiring a professional.

How to insulate a garage

Insulating a garage is a good idea for many reasons. It makes the space more comfortable, saves you money on your energy bills and ultimately increase your property value. Here’s how to do it correctly:

Supplies needed

• Insulation material
• Tape measure
• Utility knife
• Straight edge
• Staple gun and staples
• Adhesive
• Caulking gun and caulk
• Expanding foam
• Safety gear
• Ladder
• Scissors
• Hammer

Step one: Planning

The first step is to plan your approach and decide which type of insulation is suitable for your garage.

For example, a pitched roof typically requires roll or batt insulation, whereas, a flat roof is better insulated with rigid foam boards or spray foam.

Step two: Cleaning and preparation

Once you have your insulation and supplies ready to go, prepare the garage walls, ceiling and doors by cleaning them and repairing any signs of damage.

Step three: Walls

Before installing the insulation, you’ll need to install some battens, as this creates a ventilation gap between the insulation and the walls.

After installing some vertical or horizontal battens to act as a frame, measure and cut the insulation to fit between the battens snugly.

Next, install the insulation, making sure it’s flush with the edges of the battens.

Step four: Roof

The process will be slightly different here depending on what kind of roof you have.

If it’s a pitched roof, lay your roll or batt insulation between the rafters, leaving a ventilation gap between the insulation and the roof.

If it’s a flat roof, measure and cut foam boards so they fit tightly between the rafters, using glue or screws where necessary to ensure there are no gaps.

Step five: Doors

Doors are often the easiest to insulate, as you can buy garage door insulation kits.

If you have a kit, simply follow the manufacturer’s directions. If not, foam boards are usually the best option for garage doors.

Measure and cut the boards to fit tightly within the garage door panels. Secure them using adhesive, ensuring they’re flush and secure with the door.

You can also seal seams with insulation tape for extra thermal protection. Finally, test your garage door to ensure it can still open and close properly with the increased weight.

Step six: Sealing and ventilation

Using caulk or some spray foam insulation, seal any gaps and cracks you can find to prevent drafts and further improve the effectiveness of the insulation.

It’s important to have proper ventilation in the garage to manage moisture. The gap created between the insulation and the wall by the battens will help, but you may also need to install a vent.

If you have a window in your garage or you don’t mind leaving the garage door open now and again, this can also suffice.

Step seven: Professional assessment

It’s essential that you have your work reviewed by a professional to make sure it’s safe and functional. If you’re planning on converting the space into an additional living area, it might also need to be inspected for regulatory approval.

If you encountered any specific problems, or you’d rather hire a local expert to do the job to the best possible standard, enter your postcode into the search box below and connect with Checkatrade-approved contractors near you.