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How to Insulate a Garage

July 17, 2020

The intention of this article is to help you learn how to insulate a garage for energy performance, fire safety, and proper ventilation. Both attached garages and detached garages can benefit from professional garage insulation and air sealing upgrades. For attached garages, proper ventilation and fire safety are of extra concern. This is to ensure that the occupants of the home are kept safe and separate from any potential health hazards, such as exhaust fumes or airborne particulates. 

If you would like to speak with our Customer Experience Team about your garage insulation, or if you would like to arrange a time for a free insulation assessment for your home, please include your contact details into the form that is linked below. We look forward to hearing from you! 

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Why Should I Insulate a Garage?

Before you fully learn how to insulate a garage, it is important that you understand why it is important to do so in the first place. Depending on the type of garage that you own, and many other factors such as build design, timeframe, and budget, you may want to approach your upgrades in a different manner. For this reason, GNI strongly recommends that you have an insulation expert inspect your garage before you start making any upgrades or renovations. This recommendation also applies for new home builds, since it is beneficial for you to discuss your garage insulation options with a professional before you finalize your plans.

Overall, the different benefits of garage insulation vary from home to home, but these are a few of the improvements that homeowners may experience from a professional install:

  • Improved comfort
  • Increased resilience
  • Better temperature control
  • Upgraded health and safety (both in the garage and in the home)
  • Lower cost of utilities
  • Improved resale value of entire property
  • Improved noise reduction
  • Improved air quality

Garage Ventilation

For homeowners looking to secure a dedicated source of fresh air for their garage, both ventilation and air sealing need to be managed and purposefully controlled. This means that any areas where air can leak or intrude need to be identified and air sealed

Garage ventilation is also important in attached garages to make sure the home’s inhabitants are safe from unwelcome hazards, such as exhaust fumes or airborne particulates. The shared wall between the home and the attached garage should be properly air sealed to ensure an additional level of safety and energy performance. When the shared wall has effective insulation and air sealing, it provides the entire home with an energy performance boost. It does this by limiting energy loss that often occurs due to air leaks between the garage and the home.

How to Insulate a Garage with Spray Foam

To insulate a garage with spray foam means installing a product that provides an air barrier, a vapour barrier and improved energy performance all in one. Homeowners looking to climate control their garage can see tremendous results with spray foam. To best deal with exhaust fumes in both attached and detached garages, closed cell spray foam is often the better option. Since spray foam insulation can form its own air barrier and vapour barrier, only the thermal barrier is left to install - which can be as simple as covering the spray foam with drywall. 

DIY Garage Insulation

Using spray foam for garage insulation is a job that GNI recommends you leave to the professionals. Not only will this guarantee a precise and quality install that meets your exact specifications, but it also keeps you protected from any potential health hazards that may be present during the install. To learn more about using spray foam as garage insulation, please contact our Customer Experience Team at 1-800-265-1914.

How to Insulate a Garage with Fibreglass Insulation

Fibreglass insulation makes for an effective, affordable, and versatile approach to garage insulation. It is naturally non-combustible due to being made from sand and recycled glass, and can be easily installed as batts. Fibreglass insulation also makes for excellent soundproofing, which helps keep garage noises inside the garage and separate from your living spaces. 

To insulate a garage with fibreglass insulation, the first thing you will want to consider is the area you are insulating. For wall cavities, fibreglass batt insulation is both effective and affordable. However for the harder to reach places, such as rim joists, spray foam is likely to be the better option. In terms of garage insulation, both fibreglass batts and spray foam can be used alongside one another. In fact, they can both even be used within the same wall cavity through the flash and batt approach that is detailed below.  

How to Insulate a Garage Using the Hybrid Approach (Flash-and-Batt)

The hybrid approach to garage insulation, also known as flash and batt, involves the strategic use of both fibreglass insulation and spray foam within the same space. For flash and batt garage insulation, a layer of closed cell spray foam is installed across the wall cavity to provide both air sealing and moisture control. From there, cost-effective fibreglass batt insulation can easily be placed on top of the installed layer of spray foam, improving both energy performance and sound deadening. The flash and batt approach combines the strengths of both spray foam and fibreglass insulation, making it an effective and affordable option for homeowners to consider.

Interested in learning more? Fill out the form at the top of this page, or call us at 1-800-265-1914.

Western Ontario

935 Keyes Drive
Woodstock, Ontario
Canada N4V 1C3

Phone: 1-800-265-1914

Fax: (519) 539-7946
TOLL FREE: 1-800-265-1914

Muskoka, Haliburton, Northern Ontario

1027 Elwell Park Road
Gravenhurst, Ontario
Canada P1P 1R1

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Central Ontario

29 Ferndale Industrial Drive
Barrie, Ontario
Canada L4N 9V5

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Greater Toronto Area

2 Guided Court
Etobicoke, ON
M9V 4K6

TOLL FREE: 1-800-265-1914

GTA East

103 North Port Road
Port Perry, Ontario
Canada L9L 1B2

TOLL FREE: 1-800-265-1914

South Central Ontario

450 Industrial Dr,
Toronto (Milton), Ontario
Canada L9T 5A6

TOLL FREE: 1-800-265-1914

Eastern Ontario

1035 Moodie Dr #1,
Nepean, ON
K2R 1H4

TOLL FREE: 1-800-265-1914

Niagara Region

25 Lincoln Ave
St. Catharines, ON
L2P 2C7

TOLL FREE: 1-800-265-1914


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