For more than 40 years, we have helped Ontario home owners improve their energy efficiency and comfort. With a broad range of products and services, we are your insulation experts for renovation upgrades and new construction projects.
- Proudly serving Southern Ontario with 9 locations
- Professionally trained and certified installers
- High performance, brand name insulation
- Third party manufacturer warranties
- 100% Satisfaction Guarantee
We help you find the right insulation for your insulation project
Spray Foam
Cellulose
Fiberglass
Fireproofing
Air Sealing
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Start your attic insulation project with a free, no obligation in-home consultation.
Energy efficient and zero ozone depletion potential
We use the newest HFO blowing agent (the component that makes spray foam expand). It has a zero ozone depletion potential and a low global warming potential. Choosing spray foam ensures you meet or exceed the newest Ontario Building Codes and increases the energy efficiency of your home.
Perfect for new construction and retrofit projects
In most cases, open wall cavities are needed to install spray foam insulation into the walls of your home. This makes new construction and major renovation projects ideal opportunities to install spray foam for its air sealing benefit. In areas that are traditionally left open or have no cavities, such as a basement, crawlspace or attic, spray foam is always an option worth considering.
Insulate hard to reach areas such as headers and crawlspaces
The blowing agent in spray foam makes it expand up to 30 times its original volume. This allows it to fill and expand in any gaps and crevices it enters. This duality means you can easily insulate and air seal your basement or crawlspace walls and headers in a single project. We can also install spray foam to crawlspaces beneath stationary mobile homes.
Do more for your home with spray foam insulation
Spray polyurethane foam insulation is unique from other types of insulation. It is a liquid that is produced on site by combining isocyanate and resin, and is sprayed directly onto the surface you are insulating. When using 2lb spray foam, the result is a seamless insulation and air sealing solution that also provides an air and vapour barrier. When using 1/2lb spray foam, your home still benefits from a seamless coat of insulation.
Choose sustainable insulation products
At Great Northern Insulation, we seek out and install some of the most sustainable insulation products available. We also install cellulose insulation that is locally manufactured using mostly recycled paper. Regardless of the insulation product you choose, insulation will help increase the energy efficiency of your home and reduce your carbon footprint.
Improve your energy efficiency and lower energy bills by up to 20%.
Improve home comfort and be cooler in summer and warmer in winter.
Help prevent ice damming and extend the life of your roof.
Need attic insulation installed, topped up or removed in your home or cottage?
Get a free, no-obligation quote
As Ontario’s largest insulation company, we can help.
Regardless of your attic style—truss, flat or cathedral—a properly insulated and ventilated attic will improve the energy efficiency and soundness of your home. Plus, we can help plan your insulation retrofits to qualify for any available insulation rebates.
Pre-inspecting your attic ensures the best result
Developing a retrofit strategy for your attic requires an experienced and professional eye to thoroughly inspect for signs of moisture damage, as well as, examine existing insulation for damage and residual R-value. Your insulation plan will detail the recommended type of insulation for your space while ensuring proper air sealing and ventilation is achieved to reduce moisture build-up and condensation.
Your questions, answered
What is hot roofing?
Applying spray foam to the underside of your attic roof, also known as hot roofing, can be an ideal solution to finishing your attic and converting it to living or working space. Hot roofing creates an enclosure that includes your attic in the heated and conditioned area of your building. Our professionally trained and certified spray foam installers will work with your general contractor, as a subcontractor or on our own to complete this renovation. Ask us if hot roofing is right for your attic insulation project.
When should attic insulation be installed?
It is never too late to install or upgrade your attic insulation. If you have an older home, your attic may lack insulation entirely, or existing insulation may have settled and compressed. This makes the attic an ideal area to begin your air sealing and insulation project. Our specialists can remove, top up and install a broad range of insulation products for both new builds and renovations.
What R-value should my attic insulation be?
In Ontario, the recommended R-value for attic insulation is R-60. To be eligible for the Home Efficiency Rebate, you will need to increase the R-value to at least R60 from R35 for less. If you have a cathedral or flat roof, you will need to increase the R-value by at least R-14.
Why do I need attic baffles?
Attic baffles ensure your insulation does not fall into the soffits, while simultaneously allowing air to be channeled into the attic space through the exterior soffit vents. A combination of baffles, air sealing, and attic insulation will ensure a more comfortable, energy-efficient building with an attic space that will not be prone to mold or mildew.
Can I finance my attic insulation project?
You can finance your insulation project with us through Financeit. Our financing options are flexible and can be paid off in full at any time. Best of all, you can be pre-approved online before you receive your quote. Contact us for more information.
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Ensure your home’s safety meets building code
Many older homes have no insulation or insulation levels below today’s building code requirements. Over time, attic insulation can settle and compress, reducing its R-value and making the insulation less efficient. We will install or upgrade your attic insulation to meet Ontario’s Building Code and manufacturer specifications, so you can be confident that your home is safe and comfortable.
Different attics require different solutions
The goal of attic insulation and ventilation is to keep this unused space as cool and dry as possible throughout the year. This could be achieved by applying spray foam to your attic or topping up existing insulation with blown cellulose. Dual-system attic insulation achieves maximum attic performance by combining the air and vapour barrier benefits of spray foam with the cost-efficient insulative value of blown-in cellulose insulation.
Watch a dual system install
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