What San Jose Homeowners Say About Walt’s Insulation
Reviews aren’t decoration. They’re the closest thing you’ll get to standing in a neighbor’s living room and asking who they trusted in their attic. We’ve been insulating and air-sealing homes across San Jose since 2000, and every review below comes from a real customer who called our number, got a live person, and let our background-checked techs into their house. We earn these one dusty crawl space at a time.
Recent Reviews
“Our Alum Rock house was built in the 60s and the attic insulation looked like it had given up a decade ago. Walt’s crew removed the old fiberglass, air-sealed every penetration, and blew in Owens Corning AttiCat to R-38. Our upstairs finally holds temperature. The tech showed me photos of the before and after without me asking.”
Ruben G. - Alum Rock, San Jose
“We’d been putting off the crawl space for years because nobody wanted to deal with it. Walt’s installed a 12-mil vapor barrier, sealed the vents, and encapsulated the whole thing. The musty smell that used to drift up through the floors was gone within a week. They even pointed out a dryer vent that was venting into the crawl space and fixed it.”
Adriana F. - Willow Glen, San Jose
“I called at 11pm on a Saturday expecting a voicemail. A real person answered. I told them I had cold walls in the kids’ bedrooms and they walked me through what was likely going on. Tech came out Monday, found huge gaps where the walls met the floor plate, and sealed them before adding Rockwool batts. The difference in those rooms is night and day.”
Rafael M. - Evergreen, San Jose
“Got three quotes for spray foam in our detached garage that we’re converting to a home office. Walt’s wasn’t the cheapest and wasn’t the most expensive, but they were the only ones who gave us a written estimate with actual line items. They used Icynene closed-cell foam, explained why they weren’t using the cheap stuff, and the roof deck is now sealed tighter than a drum.”
Ruben D. - Cambrian, San Jose
“My SMUD bill dropped 22% the first full month after Walt’s did the energy audit and attic work. They found six recessed lights that were basically holes into the attic, sealed them with rated covers, and blew Johns Manville insulation to R-44. The auditor who did the post-work check said it was one of the cleanest attic air-sealing jobs he’d seen in San Jose.”
Adriana F. - Rose Garden, San Jose
“I know more about attic rodent issues in San Jose than I ever wanted to. Rats had been up there for years. Walt’s cleaned out the old insulation, sanitized the space, sealed every entry point, and blew in new GreenFiber cellulose. Seven months later, no signs of anything up there. The guarantee they put on the work gave me actual peace of mind.”
Ruben G. - Berryessa, San Jose
Why Customers Trust Us
Every review above mentions something you can verify before you ever hire us. A published address on South 10th Street. A live person answering at (408) 837-7384 at any hour. Technicians who arrive in uniform and passed a background check. Walt Brenner owns the company and still picks up the phone more mornings than anyone expects from the owner of a 25-year insulation business. We install products from Owens Corning, Rockwool, Icynene, Johns Manville, CertainTeed, Demilec, Knauf, and GreenFiber because we’re only as good as the material we put in your walls and attic. And every job we do, whether it’s a $400 air-sealing repair or a full crawl space encapsulation, is backed by the Done Right Promise: if it’s not done right, we make it right. No fine print. No runaround. That’s why Ruben, Adriana, and Rafael let us back into their homes, and that’s why their neighbors keep calling. If you have an attic, a crawl space, or walls that aren’t doing their job in San Jose, call (408) 837-7384. A person will answer. Ask for a free second opinion on any written estimate you already have.
Written by Walt Brenner, Owner at Walt’s Insulation, serving San Jose since 2000.