All reviews (931)

Great Northern insulation rushed the job, and caused $600 in damage. I felt sick to my stomach after seeing their work. It took me two weeks to cut back the amount they oversprayed on my walls. They sprayed foam over my outlets, sprayed foam into my ducts, and sprayed too much product behind ducts causing them to bend. They sent a second crew to fix some areas, but they left large gaps without foam. Was not the prettiest job by any means

The GNI crew, Derek (lead), Shawn and Paul, arrived on time, thoroughly prepared the cottage for spraying and then worked for 2 more days to carefully complete the significant job. Derek's spraying work was exceptionally well done and his assistants, Shawn and Paul, did a great job finishing and cleaning up afterward. We highly recommend Derek's crew at Great Northern Insulation in Gravenhurst.

Work was done quick and on time. Forgot to do 1 piece of work at outset but that got fixed quickly. The cribbing to keep the insulation in place didnt quite go all the way around so a few inches gap meant it snowed on me a little to check out the work so Ill give them a 9 not a 10. But would use again and recommend.

The crew arrived on time, completed the Job quickly, and cleaned up afterward. I highly recommend Great Northern Insulation.

The sales and installation crews were fair and prompt , clean and completed the job quickly.

Such an easy enjoyable experience dealing with the Great Northern Insulation Team. Polite, courteous, friendly , thorough and above all, meticulous, right down to the clean up! I highly recommend Great Northern Insulation to anyone. Rob Dermott

Disorganized company. Had to call repeatly for a quote time Then they said I had no appointment . Couldn't find me as the receptionist and office manager got my name wrong TWICE , no 3x. They never tried to get my name right They file their appt by name. Don't bother with them

We had GNI remove our attic insulation and install spray foam and blown cellulose insulation above that. PROS: -knowledgeable and professional staff to provide quote -one company that provides both spray foam and other types of insulation -kept their schedule CONS: -poor quality of work: 1) I looked in the attic after they finished their removal and there was so much debris left in the attic I had to remove 2 large oversized garbage bags of random debris. 2) after they installed the blown cellulose, I again went into the attic and was dismayed to find that the average depth of insulation was 10-11", when the contract specified 14-15" and this amount is required to receive the greener homes rebate. After I raised this, GNI sent the crew back again to top up the insulation (though even then it barely averages 14". -poor communication: after they completed the removal they also installed a series of baffles, as per the contract. Since our soffits have poor ventilation, a contractor friend of mine suggested it would be wise to install a baffle in each rafter gap to compensate for the poor soffit ventilation. I sent an email at 2pm on a Friday asking if the spray foam crew could install a few more baffles before they do their work on Monday. The message was never relayed and the spray foam crew didn't have any baffles with them and wasn't willing to run to Home Depot to get more. And once the spray foam is installed, this can't be retrofitted. The crew made an effort by constructing 2 baffles out of cardboard, but it was disappointing that this relatively simple request was never relayed and that more than half of the rafter gaps have no ventilation. Work was done in Nov 2021.

I saw the other reviews here and thought I had made a good choice in moving ahead with GNI for a hybrid attic installation on my home.  Nope--it turned out to be the worst experience I've personally had from any contractor that has worked on my home over the last 13 years of home ownership.  Below is my honest account of some (not all) of the low-lights of this experience.   [TL;DR] 1.) the install was scheduled to take only 3 days to complete but ultimately spanned over approximately 11 calendar days, causing significant and unnecessary disruption to my family 2.) disorganization and poor internal communication led to incorrect foam type being installed in the corners of my attic. I had to spend considerable effort to advocate for this to be addressed and resolved.  GNI needed to return to remediate to prevent future mold issues. 3.) GNI labourers needed to borrow basic tools from me because they either didn't have them, or theirs were broken. 4.) there was poor preparation work done to properly protect my refinished hardwood flooring. Had to purchase and setup my own flooring protection [DETAILS] Disorganization and poor internal communication led to GNI not installing "froth kit" foam in the corners of my attic before installing the blown in cellulose.  This "froth kit" style of foam was determined to be necessary by the GNI spray-foamer due to the shallow slope of my roof line.  Resolving this matter required me to spend significant time and effort to advocate for a resolution.  GNI's Production Operations Manager emailed and acknowledged that their oversight could potentially cause mold and mildew to my home in the future if not remedied.  Remediation was eventually completed. After the first day of removing existing attic insulation it became very clear to me that I would need to hastily take time off from my work to be present while the remainder of the install was being conducted.  I felt this was needed so that I would be able to properly advocate for things to be done correctly, and also ensure that my property was treated with a reasonable amount of care and respect.    I feel that GNI performed very minimal prep-work to protect my refinished hardwood floors, and after the 1st day of work I felt it was necessary to go purchase and setup my own flooring protection.  I also feel that GNI completely missed the mark on reasonable cleanup of materials and debris removed from my attic.  Some garbage bags of debris didn't properly make it into the driveway dumpster and instead blew around in the wind requiring me to have to spend my time cleaning up my and my neighbors' front yards, driveways, and walkways. Some GNI labourers were not equipped properly for the job, and borrowed MY tools (with permission) on several occasions as they didn't have them in their truck, or theirs were broken.  These basic items included: screwdrivers, tape measures, vacuums, and extension cords. Also, GNI installers were not equipped with a sufficient amount of rafter venting product to meet the scope of the contract, and used material that I personally procured on a previous occasion, rather than simply going to a nearby retailer to purchase. This relatively simple installation was an awful experience from the very start and right through until the very end.  GNI acknowledged these issues by offering a discount of approximately 7.7% in an attempt to make up for the experience and to cover the additional materials I needed to purchase.  While the items in the scope of work were eventually delivered, I feel this discount is not sufficient given the amount of unexpected disruption and chaos that my family needlessly experienced. ******************************************************** ******************************************************** UPDATE BASED ON REPLY FROM GNI: ******************************************************** ******************************************************** Please know that I did not change the scope of work for this project. The scope of work was always very straight forward, and included the following items: 1. removal of existing insulation 2. installation of rafter air baffles and fiberglass batts for soffit area 3. installation of approximately 2" of spray foam for air sealing 4. installation of blown-in cellulose insulation This was for an approximately 900sqft attic space aiming to achieve R60+ The "change of scope" GNI is referring to in their reply may be related to the issue that was caused when GNI installed the incorrect foam type in the corners of my attic. This seems to have been due to major disorganization and poor internal communication within GNI. I had to spend considerable effort to advocate for this to be addressed and resolved properly. GNI eventually returned to remediate their error in order to try to prevent possible future mold issues. GNI's error caused considerable delay to the work being completed, and was extremely disruptive to my household.

I wanted to let you know that the crew of John, Denny and Malcolm were fabulous today. All three of them were friendly, personable, punctual, professional and John and Denny in particular were very knowledgeable. They also left my house cleaner than when they arrived. You're truly lucky to have these guys! Matt, Steve and Sarah, I can't say enough about the three of you as well. Throughout this whole process, starting with my first call and subsequent visit by Matt, you've all been so on top of things and made this easy for me.