Business Details
46 Years
experience
Trusted Insulation Contractors in Southern Ontario
Great Northern Insulation has been a trusted leader in the insulation industry for over four decades. Our team of certified professionals is dedicated to delivering energy-efficient solutions for residential, commercial, and agricultural sectors. We prioritize ongoing staff development and utilize cutting-edge materials like cellulose, hemp, and HFO spray foam to ensure sustainability. With a 100% satisfaction warranty, we combine technical expertise with exceptional customer service to exceed client expectations. Our commitment to innovation and environmental responsibility has made us Canada's largest full-service insulation contractor. 
Services
Attic Insulation
Spray Foam Insulation
Air Sealing
Basement Insulation
Agricultural Insulation
Details
- Year established: 1980
Highlights and features
- 40+ years of insulation expertise in Ontario
- Certified professionals with ongoing technical training
- 100% satisfaction warranty on all services
- Sustainable materials like cellulose and hemp insulation
- Authorized installer for Lowe's and Enbridge rebates
Associations and certifications
- RenoMark
- eRenovate
- EcoLogo
- Greenguard
What people say
Professionalism
Knowledgeable installers
Dramatic energy savings
Quick response
Clean workspaces
Services
Spray Foam Insulation
Our spray foam insulation creates airtight seals in walls, attics, and basements. This high-R-value solution prevents heat loss, reduces energy costs, and improves indoor air quality. Ideal for residential and commercial properties, it adds structural strength while resisting moisture and pests. Clients benefit from customized applications in new builds or retrofits.
Attic Insulation
We install cellulose and spray foam attic insulation to prevent heat transfer and ice dams. This service enhances energy efficiency, reduces HVAC strain, and maintains consistent indoor temperatures. Our team removes old insulation when needed and ensures proper ventilation to prevent moisture buildup in homes and businesses.
Air Sealing
Our air sealing solutions target gaps in building envelopes using spray foam and specialized barriers. This process minimizes drafts, lowers energy consumption, and improves comfort. Commercial clients benefit from thermal imaging diagnostics to identify leakage points before applying sealing solutions.
Basement Insulation
We apply spray foam and batt insulation to basement walls and floors. This prevents cold spots, reduces humidity, and creates livable spaces. Our moisture-resistant materials protect against mold while improving overall home energy performance through comprehensive foundation upgrades.
Agricultural Insulation
Specialized insulation for barns, stables, and livestock facilities. We use spray foam to control temperature, prevent condensation, and protect equipment from freezing. Our solutions improve animal welfare by reducing heat stress and maintaining optimal humidity levels in agricultural buildings.
Questions
What types of insulation do you offer?
We provide cellulose, spray foam, fibreglass batts, and hemp insulation. Our sustainable options include 85% recycled cellulose and HFO spray foam with zero ozone depletion potential.
Do you offer rebates or financing options?
Yes, we help clients access Enbridge rebates up to $10,000 and Canada Greener Homes Loans. Our team guides you through rebate application processes for energy-efficient upgrades.
Are your installers certified?
All technicians are certified professionals with ongoing training. We maintain industry-leading standards through partnerships with RenoMark and eRenovate verification programs.
Can insulation reduce energy bills?
Proper insulation can decrease heating/cooling costs by up to 30%. Customers report significant savings after attic, basement, and wall insulation upgrades with our materials.
Do you serve commercial clients?
Yes, our GNI Management Group division specializes in commercial/industrial insulation for new builds and retrofits, including fireproofing and air barrier systems.
Videos
Reviews (6)
Linda Dench
Nov 30, 2021
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Positive:Professionalism,Quality,Value
Tiffany &Sabrina were very efficient and very professional in the insulation of the attic. I would highly recommend this company and these 2 employees. They also left my house clean.
Thanks
Tiffany &Sabrina were very efficient and very professional in the insulation of the attic. I would highly recommend this company and these 2 employees. They also left my house clean.
Thanks
Pradeep Ranchod
Nov 26, 2021
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I have to admit that the entirely new insulation which was completed by GNI made a big difference in our heating bill. So they came in and stage one was for them to remove all the old insulation and then a crew goes back in to vacuum up all debris and dust. Second stage they go in with a spray foam which hardens overnight and this foam forms the vapour barrier. This was spread over the entire floor of the attic and although the explained that they would cover around electrical switches and fan housing so that this items do not get covered with a vapour foam barrier. In our case they apparently
Don Hull
Nov 18, 2021
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Positive:Professionalism,Punctuality,Quality,Responsiveness,Value
These folks are very professional. Quote was clear, booking was organized and confirmed at every stage. The Installers Tiffany and Sabrina were polite, diligent and cleaned up afterwards. They even added a required vent without asking. I was thoroughly impressed. Donald Hull
These folks are very professional. Quote was clear, booking was organized and confirmed at every stage. The Installers Tiffany and Sabrina were polite, diligent and cleaned up afterwards. They even added a required vent without asking. I was thoroughly impressed. Donald Hull
Karen Chambers
Nov 17, 2021
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Recently Bill Barlow came to my home to evaluate my need for insulation. I am truly impressed by the professionalism and honesty of this man. Luckily and in my favour no insulation was needed. Mr Barlow has also confirmed the findings of another reputable company. This honesty is truly noteworthy in this day and age.
Karen Chambers
Karen Chambers
Lauren
Nov 03, 2021
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**Update Review** Oct 16/2021
Customer service reached out and offered us $200 in gift cards of our choosing plus $200 in cash off the job. We waited to change this review as we wanted to see the job completed. They did an excellent job and showed up promptly. Thank you for correcting your mistake.
Tried to use this business. Booked 3 weeks ago. They gave us a time frame of 8-11am. My husband emailed them and by 11:15am some woman called and told him that "we forgot and the wrong date was inputed and the guy doing the job wasn't working this week". My husband moved the entire garage out for these
Customer service reached out and offered us $200 in gift cards of our choosing plus $200 in cash off the job. We waited to change this review as we wanted to see the job completed. They did an excellent job and showed up promptly. Thank you for correcting your mistake.
Tried to use this business. Booked 3 weeks ago. They gave us a time frame of 8-11am. My husband emailed them and by 11:15am some woman called and told him that "we forgot and the wrong date was inputed and the guy doing the job wasn't working this week". My husband moved the entire garage out for these
Bailey McMillan
Oct 30, 2021
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Positive:Professionalism,Punctuality,Quality,Value
Tiffany, Sabrina& Emily were very professional, tidy & on time too. Its good to see women in this line of work too. I would highly recommend their service! I had garage insulated.
Tiffany, Sabrina& Emily were very professional, tidy & on time too. Its good to see women in this line of work too. I would highly recommend their service! I had garage insulated.
