Insulation Before & After in San Jose, CA
Anyone can tell you they do good work. Seeing it is different. We’ve been pulling back attic hatches and crawling under San Jose homes since 2000, and the before-and-after difference is usually dramatic. Here’s a look at real insulation transformations we’ve handled across the city, from Willow Glen to Evergreen. No stock photos, no touch-ups, just the kind of work we do every week.
Recent Transformations
Attic Insulation Removal & Replacement in Willow Glen
A 1960s ranch in Willow Glen still had its original fiberglass batts, sagging and packed down to about R-11. The homeowner couldn’t keep the upstairs under 85 degrees in summer. We vacuumed out the old material, air-sealed every penetration, and blew in fresh Owens Corning fiberglass to R-38. The first afternoon after we finished, the homeowner called to say the upstairs felt like a different house.
Blown-In Insulation for a Bonus Room in Evergreen
The bonus room over the garage in this Evergreen home was basically uninhabitable, freezing in winter and baking by 2 p.m. Its ceiling had a thin layer of R-13 batts that had been installed poorly and shifted over time. We dense-packed the sloped ceiling cavities with GreenFiber cellulose and added a fresh layer of blown-in fiberglass across the flat section. The room is now a comfortable home office year-round.
Spray Foam Insulation in a Downtown San Jose Crawl Space
This 1920s downtown bungalow had an open crawl space that let cold air pour through the floorboards all winter. The homeowner was running a space heater in the living room just to stay comfortable. We applied closed-cell spray foam from Demilec to the crawl space walls and rim joists, turning the entire under-floor area into a conditioned buffer zone. Floors stopped radiating cold within a day.
Radiant Barrier Installation in Almaden Valley
An Almaden Valley home with a south-facing roof was absorbing heat all afternoon, and the attic would hit 130 degrees by 4 p.m. The air conditioner ran constantly and still couldn’t keep up. We stapled a radiant barrier to the underside of the roof rafters, reflecting heat before it ever reached the insulation below. Attic temperatures dropped by a consistent 20 to 25 degrees, and the AC cycle time dropped noticeably.
Crawl Space Encapsulation & Vapor Barrier in Campbell
This Campbell home had a dirt crawl space that was pumping moisture into the house all year. The homeowner had musty smells in the hallway and condensation on the windows every winter morning. We cleaned the crawl space, laid a heavy-duty reinforced vapor barrier, sealed the foundation vents, and taped all seams. Humidity readings inside the house dropped from 70 percent to below 50 percent within two weeks.
Attic Air Sealing & Rodent Proofing in Berryessa
We got called to this Berryessa house because the homeowner kept hearing scratching sounds at night. What we found was an attic full of old, contaminated insulation and open gaps around plumbing vents and recessed lights. We removed the soiled insulation, sanitized the attic floor, sealed every gap with foam and metal mesh, and blew in fresh Johns Manville fiberglass to R-38. The scratching sounds stopped. The energy bill dropped too.
Want Results Like These?
These are the kinds of transformations we make every week across San Jose. If your attic is hot, your floors are cold, or your energy bill doesn’t match the square footage, we can take a look. Call (408) 837-7384 and a live person answers, 24/7. Free second opinion on any written estimate, no trip charge in our county, and 10% off for seniors and veterans, always.
Written by Walt Brenner, Owner at Walt’s Insulation, serving San Jose since 2000.