Demilec Insulation Removal & Replacement in San Jose: What to Know First
We remove and replace Demilec spray foam insulation throughout San Jose, and most full removals are done within one to three days depending on the size of the affected area. You can expect to pay between $2,800 and $7,500 for a typical attic removal and re-insulation job, with smaller spot removals running considerably less. If you’ve got a Demilec product that’s failing, or you suspect it’s the source of an odor, moisture, or air-quality problem, call us at (408) 837-7384 and we’ll give you a straight answer on what you’re dealing with.
This page is for San Jose homeowners who have Demilec spray foam in their walls, attic, or crawl space and need it removed and replaced properly. Whether it’s Heatlok HFO, Sealection 500, or an older Demilec formula that’s underperforming, the removal process is different than what most insulation crews are used to, and getting it wrong creates a bigger mess than the one you already have. We’re an independent Demilec service provider, not a manufacturer rep, so our only interest is fixing your house.
How Demilec Products Fail - and How We Fix Them
Demilec makes good spray foam, but like every insulation product, it has failure modes that show up in Bay Area homes. Here are the ones we see most often in San Jose:
- Heatlok HFO shrinkage and separation. This closed-cell foam occasionally pulls away from framing as it ages, especially in attics that swing between hot and cold. The result is air leaks where the foam meets the studs or rafters. We remove the affected section and re-apply with proper surface prep, which usually means cleaning the substrate and checking moisture levels before the new foam goes in.
- Sealection 500 odor complaints. This open-cell product can hold a chemical or musty smell if it was installed too thick in one pass and never fully cured, or if roof leaks have kept it damp. We remove the saturated or uncured foam outright rather than trying to encapsulate it. Covering it up just seals the problem in.
- Heatlok Soy 200 moisture trapping. In San Jose crawl spaces, we’ve pulled out Demilec foam that looked fine on the surface but was holding water against the rim joists underneath. When the foam bonds poorly to dusty or damp wood, water seeps in behind it and rots the framing without showing on the surface. Removal and proper moisture remediation comes before any new insulation.
- Over-sprayed or misapplied Demilec foam. We see jobs where someone sprayed Heatlok HFO into enclosed wall cavities at the wrong temperature and it never expanded correctly, leaving voids and hard spots. This is a removal-and-reapplication job. There’s no shortcut for drilling into closed cavities, extracting the bad foam, and doing it right.
- Old Demilec formulas no longer supported. Some homes in San Jose still have early-2000s Demilec products that the company no longer manufactures. If the foam is degrading or failing, replacement with a current product is the only real fix. We’ll tell you if a compatible patch is possible or if full removal makes more sense.
Our Demilec Insulation Removal & Replacement Process
Every Demilec removal job follows the same path, whether it’s a small bathroom wall or a whole attic:
- 1
We inspect and diagnose. Walt’s crew assesses the foam’s condition, checks for moisture, documents the affected area, and gives you a written quote before any work starts. No surprises after the fact.
- 2
We set up containment. Spray foam removal creates dust and debris. We seal off the area with plastic sheeting and run HEPA-filtered negative air machines so the rest of your house stays clean.
- 3
We remove the Demilec foam. Depending on the application, we use manual scraping, oscillating tools, or specialized foam removal equipment. Open-cell comes out faster than closed-cell. We take care not to damage wiring, plumbing, or the framing underneath.
- 4
We prep the surface. The substrate gets cleaned and checked for moisture or damage. If we find rot or mold, we flag it and handle it before any new insulation goes in.
- 5
We install the replacement. We work with Owens Corning, Rockwool, Johns Manville, CertainTeed, Icynene, Knauf, GreenFiber, and Demilec products where appropriate. The replacement product depends on the application and your budget, and we’ll explain the tradeoffs in plain English.
- 6
We clean up and verify. We remove all containment, inspect our work, and run through what we did. Every job is covered by our lifetime Done Right Promise. Do it right or do it twice, and we’d rather not see you twice.
What Demilec Insulation Removal & Replacement Costs in San Jose
Here’s what we typically see in San Jose for Demilec removal and replacement:
- Small spot removal (single wall cavity, small ceiling area): $600-$1,500
- Partial attic removal and re-insulation: $2,800-$5,000
- Full attic removal, air sealing, and new blown-in or batt insulation: $4,500-$7,500
- Crawl space Demilec removal and replacement: $3,000-$6,500 depending on access and square footage
What moves the price is access, foam type, and how much surface prep the substrate needs. Closed-cell Demilec foam takes longer to remove than open-cell. Attics with low clearance or lots of obstructions run higher. Call (408) 837-7384 for a free estimate and we’ll give you an exact number for your house.
Why San Jose Homeowners Call Walt’s Insulation for Demilec Work
We’ve been doing insulation work in San Jose since 2000. We’re the one down the road, locally owned and owner-operated, with a published address and a license number you can look up. When you call, a live person answers, 24/7. No voicemail, no answering service, nobody in another state reading a script.
Our technicians are background-checked and uniformed, so you know exactly who’s walking into your house. We serve every San Jose neighborhood, from Willow Glen to Alum Rock to Evergreen, and we know how Bay Area homes behave. Most of the time, we’re also the crew that gets called in to fix another contractor’s foam removal attempt, so we’ve seen everything. We work across brands including Demilec and Reflectix, and we’ll tell you honestly which replacement product fits your situation. Every Demilec removal and replacement job carries our lifetime Done Right Promise. If it’s not done right, we make it right.
FAQs
For small spot removals, yes, we can usually get the job done same-day or next-day depending on our schedule. Full attic or crawl space removals typically take one to three days. Call (408) 837-7384 and we’ll give you a realistic timeline for your specific job.
For most full removals we recommend staying elsewhere while we work, especially if the affected area is large or connected to your living space. We use HEPA filtration and containment, but the process creates dust and airborne particles you don’t want to breathe. We’ll tell you upfront if the job requires you to be out of the house.
It depends on the failure mode and the square footage affected. Small voids or shrinkage can sometimes be addressed with targeted removal and reapplication. Widespread odor, moisture, or degradation usually calls for full removal. We’ll give you an honest recommendation either way, with pricing for both options.
If your Demilec product is still under manufacturer warranty, we recommend checking the terms before removal. Many Demilec warranties cover product defects, but removal and labor may not be included. As an independent service provider, we can document the failure with photos and measurements to support your warranty claim.
We replace Demilec foam with whichever product best fits the application. That could be new Demilec spray foam, Owens Corning fiberglass, Rockwool mineral wool, Johns Manville batt, CertainTeed, Icynene, Knauf, or GreenFiber blown-in. The right answer depends on your climate zone, the space, and your budget, and we’ll walk you through it.
If you’ve got Demilec insulation that’s failing or suspect it’s the source of a problem in your San Jose home, call us at (408) 837-7384. We’ll schedule a free estimate, take a look, and tell you exactly what you’re working with. Seniors and veterans always get 10% off. There’s no trip charge in our county, and if you’ve got a written estimate from someone else, we’ll give you a free second opinion.
Written by Walt Brenner, Owner, Walt’s Insulation at Walt’s Insulation, serving San Jose and nearby areas.