Verified record
Green Collar is a South Hadley energy-efficiency contractor — insulation, air sealing, spray foam, and weatherization work, plus heat pumps, mini-splits, and window installation — and a participating Mass Save Independent Installation Contractor. The Better Business Bureau accredits the company with an A+ grade. Its most recent review, from September 2026, said Brian installed 12 windows in three days by himself, calling him friendly, courteous, and knowledgeable. That kind of praise repeats across years of reviews with different crew names attached. In a 2024 review, a homeowner said Jeremiah and his crew worked hard in a small, hot attic without wasting time and explained the job from start to finish. A 2023 review said a crew led by Robert measured and installed replacement windows perfectly, and another 2023 review praised a three-person crew for craft skill and professionalism beyond their years on a challenging project. A 2021 review described a mini-split installation with good advice, prompt scheduling, and help navigating a Mass Save rebate. Reviews from 2019 through 2022 tell a consistent story under different crew leads — Mark, Garrett, Wilson, Travis — arriving on time, working efficiently, and leaving the home clean. Across platforms, the ratings stay high: Angi and HomeAdvisor both show 4.9 stars from 28 reviews, Thumbtack shows 4.8 from 43, and Google shows 4.8 from 13. Better Business Bureau lists two license numbers for the company, CS-108817 and 181415, and BuildZoom separately lists a Home Improvement Contractor license claim. For insulation, air sealing, and other Mass Save energy-efficiency work, this is a well-established choice with a large, seasoned crew.
Typical Greater Boston range for this kind of work, from regional averages — not a quote from Green Collar. Use it to sanity-check bids, then get the real number in writing.
Estimated range
$5,000 – $11,400
Typical HVAC project around $8,200
“Jeff, Quinn, and Jordan were a professional and knowledgeable crew. They treated us and our pets with respect and left our house in good condition after the insulation install. We would highly recommend Green Collar to our friends and family!”
Brian from Green Collar was exceptional. I would highly recommend him and Green Collar in general. He installed 12 windows in 3 days by himself. Friendly courteous and knowledgeable.
Bryan installed new windows for our house and did an amazing job!!! What a wonderful experience. He was kind, informative and very skilled. I can’t express enough how incredible he is.
I had a terrible experience with Green Collar. They didn't listen to or investigate the concerns about the cold air coming into the house under the cabinets and applied their boilerplate sill plate and airsealing quote. They took down new existing insulation and replaced with with lesser quality, left a mess of spray foam on multiple items in the basement and left gaps on the wall. Screws were drilled through a wooden door such that you can see them on the finish side... The air continues to come into the house under the cabinets. This company was set up to collect green energy subsidies without actually providing any energy savings to the home. I reached out on several occasions but never received a reply.
Jeff and his crew (Nick and Clint) did an awesome job insulating my old house. They really put in 4 huge days of effort crawling all over the place blowing insulation in and closing up every leak in the house. Even their manager, Tyler, showed up and went to work. They were diligent in being as neat as possible and careful to not damage anything (there is a lot of stuff all over my house). I would highly recommend. Hard working and skilled.
Jeremiah and his crew did a fantastic job. They arrived on time, worked very hard in the small hot attic space, did not waste time and were very professional. Jeremiah explained from start to finish what the job entailed. When the job was completed, Jeremiah explained all that was done and wanted to make sure we were completely satisfied before leaving. They also cleaned up and did not leave a mess. We are very pleased with Green Collar and Jeremiah and his crew!
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Certified attributes are verified against the public registry. Others are the business's own statement.
1 change recorded — last scanned Sep 17, 2026.
Transparent diagnostics5.0
Broad plumbing and HVAC range5.0
Repeat, years-long customers5.0
Water heater and boiler installs5.0
Decades-long customers5.0
Mass Save weatherization4.9
Same-day AC fixes during peak heat waves3.8
Saturday toilet fixed within the hour4.1