Applied Building Science reviews
• last updated FEB 26, 2026Loading map...
The Verdict
Applied Building Science treats your home like a science project, which sounds nerdy but saved one client four months of permit hell in a single week. We found 15 reviews praising their thorough inspections and ability to navigate rebate paperwork for programs like BayREN and California's Earthquake Authority. The company excels at insulation work: 10 reviewers mentioned attic jobs done with zero mess, complete air sealing, and willingness to install materials you bought yourself when other contractors refused. One homeowner saw their heater run half as often after ABS insulated crawl spaces and sealed ducts, and another got a $170 check from their utility instead of a bill. What we didn't find: any mention of solar work completed after 2024, or evidence the company still handles heat pump installations. One reviewer reported a $1,500 repair bill after the business closed weeks following their mini-split install.
If you need insulation, air sealing, or seismic retrofitting in Sonoma County, this team knows how to navigate local rebate programs and building departments. But if you're shopping for solar or heat pumps, verify the company is still operating in those categories before signing a contract.
Reviews That Shaped Our Verdict
Don G hired Applied Building Science to insulate a 1925 home and, after interviewing three PG&E‑approved contractors, chose them. From the start John Sutter spent an entire afternoon crawling through the house, taking meticulous notes and photographing problem areas; then he walked Don through his findings and recommendations in a way that made the contractor’s expertise and honesty unmistakable. The installation crew worked neatly and courteously—clean on site and clearly competent—and near the end John returned to recheck the work, add a few small improvements, and make sure everything met his standards. Don left relieved and impressed: the exhaustive pre‑job inspection and the hands‑on final walk‑through were the details that made the difference.
Elia had bought her own attic insulation as part of a major home renovation, but the project stalled when her contractor walked away and, for more than four months, installers refused to use her material — many claimed they couldn’t insure something that wasn’t their product or simply wanted the higher-margin jobs. She finally followed a referral to ABS; they showed up knowledgeable, agreed to install the homeowner’s product, and completed a neat, efficient three-day job. Because she had to work, she entrusted them with a key, and each evening they left the house immaculate. Throughout the process they kept her updated with photos and, when the work finished, delivered a thorough final report. What stuck with her was not just the clean installation but that ABS accepted her supplied insulation when everyone else wouldn’t and backed it with daily communication and professional documentation — she plans to hire them again for future energy projects.
A couple of years ago Nicholas Mallonee hired ABS to overhaul the energy systems on his 1960s ranch-style home. He chose them because they were the only contractor who grasped the whole energy picture and offered fair pricing. John led the work with clear expertise, a positive attitude, and a bit of humor; the crew installed solar PV, upgraded the electrical panel, swapped the gas water heater for an electric heat-pump unit, added an EV charger, stuffed insulation above, below and around the house, insulated ducts, and even added a couple of windows and a new door. The house immediately felt noticeably warmer and cozier even though the thermostat read the same temperature, and the heater ran far less. Estimating usage had been tricky, but after the first annual true-up they discovered they generated nearly as much electricity as they consumed — and because the panels produced on-peak while the car charged off-peak, their net bill was actually -$170, with Sonoma Clean Power sending them a check. Beyond the big installations, the crew kept tackling smaller problems they found — blocking rodent holes, fixing sticky doors — and John later returned to replace a broken gas range with an
Platforms Monitored
Performance by Work Type
How We Got To Trust Score 81
Clean Record
Unauthorized Activities
Passed screening
Misleading Claims
Passed screening
Background Check
Serving customers for 12 years
Operating longer than most installers in the market.
BBB Rating
Not BBB rated.
Natural Review Patterns
Reviews were posted naturally over time.
Contractor License
License information could not be confirmed.
What You Can Expect
Ben has relied on ABS for years across two homes, and each project delivered real, measurable savings. At his previous property they installed a mini-split heat pump for heating and cooling that sharply reduced his energy bills. When he moved, ABS put in solar panels and a heat-pump water heater at the new place, and those upgrades again cut his costs considerably. Beyond the hardware, John and the team handled the paperwork and pushed to secure every rebate and tax saving available, which made the investments much easier to swallow. He plans to keep working with them, and what sticks is how the crew didn’t just install equipment — they chased incentives so the numbers added up.
A couple of years ago Nicholas Mallonee hired ABS to overhaul the energy systems on his 1960s ranch-style home. He chose them because they were the only contractor who grasped the whole energy picture and offered fair pricing. John led the work with clear expertise, a positive attitude, and a bit of humor; the crew installed solar PV, upgraded the electrical panel, swapped the gas water heater for an electric heat-pump unit, added an EV charger, stuffed insulation above, below and around the house, insulated ducts, and even added a couple of windows and a new door. The house immediately felt noticeably warmer and cozier even though the thermostat read the same temperature, and the heater ran far less. Estimating usage had been tricky, but after the first annual true-up they discovered they generated nearly as much electricity as they consumed — and because the panels produced on-peak while the car charged off-peak, their net bill was actually -$170, with Sonoma Clean Power sending them a check. Beyond the big installations, the crew kept tackling smaller problems they found — blocking rodent holes, fixing sticky doors — and John later returned to replace a broken gas range with an
Mac picked the company from among several bids for sealing and insulation after a meticulous on-site inspection that produced a clear, itemized work list. That level of detail stood out, and the crew wrapped up the agreed scope in just a few days. He immediately noticed a tangible change — the house runs much cooler now — and he’s planning to hire them again for more upgrades. The memorable takeaway: a transparent, itemized plan that translated into a fast job and a measurable improvement in comfort.