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How to Insulate Basement Walls in Ontario

June 11, 2020

This article details how to insulate basement walls in Ontario for both new home construction and retrofits. While DIY insulation can be effective in some scenarios, GNI strongly recommends that you use an industry professional for your basement insulation upgrades. With a professional on hand, you can be sure that you are upgrading in the right way. You can also be sure that your basement insulation is well equipped to deal with any possible issues that may arise, such as those that stem from poor moisture control. This will help you prevent mould in the Ontario climate and maximize the lifespan of your basement insulation. 

To get in touch with the GNI Customer Experience Team, please input your contact details into the form located below. This will allow you to start a conversation with us about the basement insulation in your home. Once you are in touch with one of our team members, you can also schedule a time for a free insulation assessment in Ontario.

Why Should I Insulate My Basement Walls in Ontario?

Basement walls in Ontario should be insulated to improve the home’s overall energy performance and to help prevent mould. Basement insulation can also help add soundproofing in entertainment rooms, such as home theatres or music studios. Overall, the benefits of basement insulation can be seen throughout a home. This includes benefits such as:

  • A lower cost of utility bills
  • Improved home comfort and fewer drafts on every floor
  • Higher resale value for the home
  • Increased mould prevention
  • Cleaner air quality
  • Upgrades may qualify for Ontario Energy Rebates

What Insulation is Used to Insulate Basement Walls in Ontario?

For both new home construction and retrofits, there are four main types of insulation that can be used to insulate basement walls in Ontario. This includes: spray foam insulation, fibreglass insulation, cellulose insulation, and mineral wool insulation. However, you are not limited to using only one type for an entire basement - or even a single wall. These four types of basement insulation can be combined in order to maximize performance, affordability, and environmental sustainability. A GNI home insulation expert can help you make sense of your options and possible next steps. 

Spray Foam Insulation

Spray foam insulation makes for fantastic basement insulation. It is a versatile product that can be successfully applied in tight spots and hard to reach places, such as basement rim joists. When professionally applied, it provides excellent air sealing and moisture control to help prevent mould throughout your entire basement. To strike a balance between environmental sustainability and performance, spray foam insulation can be strategically combined with other types of basement insulation. This could include using fibreglass insulation for wall cavities and spray foam insulation for basement rim joists and other key areas; getting you the most out of both performance and environmental sustainability. 

Also, with changes being made to the blowing agent used to install spray foam insulation, (HFCs are being phased out and replaced with HFOs), the product is becoming even more environmentally sustainable. These changes allow for spray foam insulation to carry a significantly lower Global Warming Potential than it has previously, meaning homeowners can use it more liberally while maintaining strong environmental sustainability.. 

Fibreglass Batt Insulation

To insulate basement walls in Ontario with fibreglass batt insulation, you will likely need to have exposed wall cavities. In an unfinished basement without any framing or studs, fibreglass batt insulation can easily be installed as a blanket wrap. This allows for a quick and effective install that will improve energy performance in a cost-effective manner. Fibreglass batt insulation also carries strong environmental sustainability, since it is made out of recycled materials. The recycled glass and sand that make up fiberglass batts contribute to their ability to prevent mould by not absorbing any water. In addition to this, the recycled materials also help provide additional soundproofing and are what makes fibreglass batt insulation non-combustible. 

Cellulose Insulation (Blown-In Insulation)

While cellulose insulation can also be used to great effectiveness in an open wall cavity - just like spray foam and fibreglass - it provides an excellent solution for insulating basement walls that have already been finished or covered with drywall. When basement walls are insulated with blown-in cellulose insulation, energy performance and home comfort see significant improvements. 

Mineral Wool Insulation

Rockwool mineral wool insulation is a common choice to insulate basement walls in Ontario. Made with a stone fibre composition, Rockwool mineral wool insulation is naturally fire resistant and can be applied to basement walls just like fibreglass batts (i.e. a blanket wrap). Boasting a long lifespan, Rockwool mineral wool also provides lasting thermal protection and additional soundproofing, making it a terrific choice for home music studios or entertainment centres. 

How to Retrofit Basement Insulation

If you are looking to retrofit some basement insulation for your home in Ontario, you should consider a few things first. Are you looking to make major or minor changes? Are you looking to upgrade comfort, energy performance, or perhaps soundproofing? These questions, among others, are best answered by an industry professional or through a home energy audit. The unique circumstances for each basement changes from home to home, but by discussing your options with an insulation expert, you can most accurately and affordably target the basement insulation retrofit that you are after. 

Avoiding DIY Insulation

You may be tempted to do some DIY insulation, however there are a number of potential risks and health concerns that can arise during the process. For DIY old insulation removal, there is the possibility of disturbing hazardous particles that can become airborne within your home. In terms of a DIY insulation install, GNI recommends that you contact an industry professional before you attempt any upgrades yourself. This will help ensure that you are targeting the right areas, and that you are made aware of any potential health hazards that may be lurking.   

How to Insulate Basement Walls in Ontario for New Construction

If you need to insulate basement walls in Ontario for the construction of a new home, you have several options. All three of the previously mentioned types of basement insulation can be used with great effectiveness in new home construction. They can also be used alongside one another to strike a balance between performance, cost-effectiveness, and environmental sustainability.

Depending on your build and your plans for the future, your most cost-effective option for basement insulation may change. GNI’s insulation experts can help you determine your options on a per-case basis; ensuring that you are targeting the most cost-effective option for your goals.

How to Insulate Basement Slabs to Prevent Radon Gas

Radon gas is invisible, radioactive, naturally occurring, and poses serious health risks over long term exposure, such as lung cancer. Spray foam is the most effective choice to insulate basement slabs for radon gas protection. When professionally installed, spray foam insulation provides an airtight and watertight barrier, helping to protect you from any radon gas that may be rising off the soil under your home.

It is important to note that even with basement slab insulation, radon gas can still infiltrate a home through any available openings. To ensure you are well protected against radon gas leaks, please speak with our Customer Experience Team 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

Southwestern Ontario

7035 Industrial Drive
Comber, Ontario
Canada N0P 1J0

TOLL FREE: 1-800-265-1914

Muskoka, Haliburton, Northern Ontario

1027 Elwell Park Road
Gravenhurst, Ontario
Canada P1P 1R1

TOLL FREE: 1-800-265-1914

Central Ontario

29 Ferndale Industrial Drive
Barrie, Ontario
Canada L4N 9V5

TOLL FREE: 1-800-265-1914

GTA East

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

TOLL FREE: 1-800-265-1914

GTA & 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


259 Campbell Street
Sarnia Ontario
Canada, N7T 2H3

TOLL FREE: 1-800-265-1914

Niagara Region

6260 Don Murie St
Niagara Falls, ON
L2G 0B4

TOLL FREE: 1-800-265-1914


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