Guide to Effectively Insulate Your Garage

Every year homeowners make that last-minute dash to their favorite hardware store or garden center for supplies to winterize their home and garage. This year you're in luck. We might be able to save you a few dollars on your energy bill.

Several important dynamics go into efficiently winterizing your garage. Instead of going in blind, it helps to make a checklist of EVERYTHING you need.

With a little luck, this could be the winter that saves you the most money in a long time. Follow the list and add extra items if you feel like they need attention.

This garage door is an Eastman E-21 design, 9' x 7' size, Ice White doors and overlays, 8 lite Orion windows.

You like this look? These garage doors are in Eastman E-21 Design, 9' x 7', Ice White doors and overlays, 8 lite Orion windows.

Prepare Your Garage Door Beforehand

This garage door is an Eastman E-21 design, 9' x 7' size, Ice White doors and overlays, 8 lite Orion windows.

You like this look? This garage door is a North Hatley LP Design, 9’ x 7’, Desert Sand Color, with windows with Richmond Inserts.

What Do You Need to Know About R-values?

When the weather gets cold, it doesn't take much of that cool air to enter your garage through gaps that would normally go unnoticed. Windows, edges of doors, and the doors themselves can make a substantial difference if they are made of thin material that doesn't have a decent R-value. If you've never heard of R-value, it's important that you get familiar with this term. When it comes to your garage and home's insulation, the R-value can make or break your energy bill.

A high R-value does a better job at protecting the area in question from cold air. Basically, the R-value is a number-based rating system that dictates how efficient a wall, door, or any other material is at insulating. Most ceilings or roofs are rated at R-40, and regular interior walls are somewhere around R-16.

How much thermal insulation do you need for your garage?

The garage door is probably more important than any other area of the garage. The area of the door is so massive that an inefficient R-value will leave tons of cool air rolling into the garage. It doesn't matter how well the rest of the garage is insulated; if the door is rated poorly, your garage is going to be frigid. The right R-value for your garage depends on these factors:


The garage walls should have about the same rating as the walls in your home. Somewhere around, R-16 should provide a comfortable amount of insulation.

Attached vs. detached

When a garage is detached, the R-value doesn't have to be as high to provide an efficient level of insulation. R-12 will probably do the trick for a detached garage. An attached version will need to hit that magic R-16 mark.


If the garage is exposed to full-time use through family gatherings, working out, gaming, or even someone using it as a living space, R-16 is mandatory. You want to be able to accommodate the people frequenting your garage without getting cold.

Insulating materials

There are 2 main materials used to insulate garage doors:

Polyurethane is applied as a foam that gets inserted between the panels of the garage door. This style of insulation is said to be twice as efficient as polystyrene for several reasons. It's denser, and it fills in spaces more efficiently. The foam enters between the panels and spreads quickly, giving it more access to hard-to-reach spaces than the polystyrene alternative. Another benefit of his material is the fact that it makes the garage door more durable. The fast-spreading polyurethane does a great job of reinforcing the door panels.

Polystyrene is the second insulation for garage doors. You probably know it better than Styrofoam.

See the difference between polyurethane (on the left) and polystyrene (on the right) insulation for garage doors

See the difference between polyurethane (on the left) and polystyrene (on the right) insulation for garage doors.

Other essential elements you don't want to forget

Bottom garage door gap

Your bottom garage door weatherstripping should be checked and maintained twice a year. The best times for this are right before summer and right before winter. An efficient bottom sealing weatherstripping will block mice, cold air, leaves, dirt, pollen, and other annoying debris from entering the garage. An efficient piece of weatherstripping should be free from any major rips or holes and contact the concrete for the full length of the door.

Garage door opener

Every time you close the garage door, make sure it is brought all the way down and contacting the floor. Test your garage door opener and keep fresh batteries installed at all times.

Garage door gap at sides and/or top

Vinyl weatherstripping is a great material to install around the garage door. This type of weatherstripping has a beautiful visual element as well, doing a great job of trimming out the sides and top of the garage door.

Are Your Walls Well Insulated?

Walls and ceilings

Your ceilings should be rated higher than the walls and doors. A good number for your ceilings is around R-40. Most cold air is lost through drafts from the roof or attic.

These 4 easy steps from can help if you want to insulate your garage on your own.

Step 1: Clear your garage walls of everything hanging to it by nails and screws

Step 2: Repair any damage and seal the gaps. This includes holes and places that let air through near windows

Step 3: Put fiberglass insulation in place. You can be generous with it

Step 4: Place drywall over the insulation, making sure it's sealed tight.

Insulate your walls to save energy costs with foam.

Insulate your walls and ceilings adequately, and you will save energy! Image from Pixabay.


Windows can add a great lighting element to your garage. Natural light does a great job of brightening up the otherwise drab and dreary appearance of an all-concrete room.


Use weatherstrip tape around your windows. This tape does an excellent job of sealing those small cracks that can be hard to pay attention to with caulking, mud, or glue.


Refer to this article to learn which caulk is best for you, considering that many types of applied caulking end up drying and cracking fairy quickly. Using high-quality caulk can prevent this drying and lead to long periods of insulation.

Window treatments

Different treatments exist to add to your windows, like thermal curtains and special types of tint. These are a great alternative to things like caulk.

Note: Garage door windows can benefit from these same treatments.

Light switches and outlets

Conservation Mart estimates approximately 2 to 5% of air infiltration comes through your electrical outlets. Unfortunately, most homeowners forget to weatherize this part of their garage.

These 7 easy ways to help you insulate your garage switches and reduce heat loss can help save money in places you'd normally be guaranteed to lose it.

Reduce condensation in your garage

Condensation is a normal occurrence in most garages because of the contrast in temperatures and the properties of concrete. Use these tips to reduce moisture building through condensation.

Keep the water out from your garage floor

It's especially important that you keep water away from your garage floor. Since concrete is incredibly porous, this water can enter the concrete mixture and weaken it significantly. This weakening leads to cracks and other damage.

Bacteria can develop from humidity and condensation, and the garage is famous for producing both of these types of moisture.

A garage door that keeps rainwater from running in your garage.

This garage has the proper garage door seal, and floor finishes to prevent water from leaking.

A dehumidifier or some other type of ventilation system can help your garage fight extra moisture. These small appliances are also a cost-efficient solution.

Heat your garage to control your home temperature

A small space heater can go a long way in heating your garage. With the right insulation, sometimes a small heater is all you need to keep the garage warm.

● Avoid damaging electronics in the garage

● Important items stored in the garage are much safer

● Protects the walls and other wood from swelling and warping

● It helps different components on your vehicle

● Can improve the temperature of your house.

Do you Still Have Questions Regarding Your Garage Door Insulation?

Now that you have this advice, you know how to properly insulate your garage from top to bottom. We have shared our best tips to prepare your home for winter and keep warm air inside.

Have you heard about our garage door maintenance and repair services?

Atlas-Coles Door Systems can visit your home and tell you exactly what needs to be replaced and what is still in good shape! Before you decide on hardware accessories, let one of our experts pay you a visit.

We have garage door technicians that can make your life easier by performing all of the maintenance your garage door needs. These guys are real professionals and will make sure your door is operating in perfect condition.

Is all that winterizing you're doing not making the difference it should? Most likely, it's your garage door that's the culprit. It could be time for a full replacement. Contact us at 1-877-545-3667!

Buying a garage door can be confusing and even overwhelming. There's no reason to go through anxiety when you're choosing your perfect garage door and garage upgrades.

Our image gallery can give you a glimpse into some of our past work. Check out our Design Centre to create a virtual version of your ideal garage door.

Whenever you're ready, get a free quote by email, and let us get you started on replacing that old garage door and saving you money on your utility bill!

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