Demilec Blown-In Insulation in Morgan Hill: What to Know First
We provide independent Demilec blown-in insulation service in Morgan Hill, typically completing attic top-ups and dense-pack wall jobs in one day with a written price delivered before any work starts. Most Morgan Hill homes we see with existing Demilec insulation need air sealing first - blowing new material over an unsealed attic floor is, as Wes Okafor puts it, “expensive decoration.” Call (669) 280-8103 for a free estimate with upfront pricing.
This page is for Morgan Hill homeowners who already have Demilec insulation in their attic or walls and need service, top-up, or replacement - whether your blower door numbers have slipped, you’ve found settled material, or you’re finishing an addition and want to match the existing system.
How Demilec Products Fail - and How We Fix Them
- Demilec SEALECTION AgriBalance settled below rated depth in attics. The open-cell spray foam component in hybrid systems can shrink 5-10% over time in Morgan Hill’s wide temperature swings, leaving the blown-in cellulose companion layer under-spec on R-value. We remove the settled material, re-establish the air barrier at all top plates and can-light boots, then reinstall to true depth with fresh blown-in cellulose.
- Demilec Heatlok Soya HFO loses adhesion at rim joists in crawl spaces. The bio-based spray foam’s bond line fails where concrete or old wood has residual moisture - common in Morgan Hill’s clay-heavy soils after winter rains. We cut back the failed foam, dry the substrate with targeted ventilation, then dense-pack the rim joist cavity with blown-in fiberglass that doesn’t require a perfect bond surface.
- Demilec ECOLOGIC Silver Label cellulose shows mold at eaves. The borate treatment degrades when roof leaks or bathroom vents dump moisture into the attic - we’ve traced this in several homes near Oakwood Avenue with original 2015-2018 insulation. We remove the affected material, fix the moisture source, treat the sheathing, and reinstall fresh borate-treated blown-in cellulose.
- Demilec Arctic Foam companion batts compress in sloped ceilings. The hybrid system relies on blown-in fiberglass over foam in vaulted spaces, but installers often over-dense the cavity and collapse the fiberglass’ loft. We pull the compressed material, verify the foam layer’s integrity, then re-blow at proper density - 0.5 to 1.0 pounds per cubic foot for fiberglass in sloped applications.
- Demilec AgriBalance top plates leak despite full attic coverage. The blown-in component masks but doesn’t seal the plate-to-drywall joint - a detail we find missed in roughly half the Morgan Hill retrofits we inspect. We pull back material 18 inches from each plate, foam-seal the joint with compatible one-component sealant, then re-blow to blend with existing depth.
Our Demilec Blown-In Insulation Process

- 1
Call and scope. A live person answers at (669) 280-8103, 24/7. We schedule a site visit, text you when the technician is en route, and arrive with a blower door and thermal camera.
- 2
Diagnostics and documentation. We run a blower-door test - a pressurization reading that shows, in one number, how much air your building envelope is losing. We photograph existing Demilec material, note the series and installation date if visible, and identify all air leaks before any insulation moves.
- 3
Written price before any work starts. Under Haven Standard Clause 1, you get a flat price, written scope, and written warranty before anyone lifts a tool. No exceptions.
- 4
Air sealing first, then insulation. We seal every penetration - top plates, recessed-can boots, attic hatch perimeters, plumbing and electrical penetrations - because installing R-38 over an unsealed attic floor is expensive decoration. Seal the leaks first. The insulation just holds what you’ve already captured.
- 5
Material selection and installation. For Demilec systems, we match or exceed the original R-value using compatible blown-in cellulose or fiberglass from our supplier network - Owens Corning, Johns Manville, Knauf, Rockwool, CertainTeed, Icynene, Demilec, GreenFiber, or Reflectix where appropriate. No proprietary lock-in.
- 6
Test, document, and close. We re-run the blower door and publish your before-and-after numbers. You receive a Documented Photo Record, the written warranty, and our 365-Day Done Right Promise.
What Demilec Blown-In Insulation Costs in Morgan Hill
| Job Type | Typical Range | What Moves the Price |
|---|---|---|
| Attic top-up (existing Demilec, 1,000-1,500 sq ft) | $1,800-$2,800 | Current depth, access difficulty, extent of air sealing needed |
| Attic removal and replacement (mold or settlement) | $3,200-$5,500 | Volume of material to remove, sheathing treatment, disposal fees |
| Dense-pack wall insulation (Demilec retrofit, per sq ft of wall) | $2.50-$4.00/sq ft | Cavity depth, drill-and-fill vs. interior access, electrical obstructions |
| Rim joist dense-pack (crawl space, Demilec foam failure) | $1,400-$2,600 | Linear feet, height, moisture remediation required |
| Air sealing package (standalone, before any insulation) | $1,200-$2,400 | Blower-door starting number, complexity of penetrations, one-story vs. two-story |
These are real Morgan Hill ranges based on jobs we’ve completed from the older homes near Oakwood Avenue up to the newer builds off East Main. Your written price comes after we see the space - never before. Call (669) 280-8103 for a free estimate.
Why Morgan Hill Homeowners Call Topside Attic Insulation Morgan Hill for Demilec Work

We’ve logged jobs across Santa Clara County since 2016, and Morgan Hill’s specific mix - older ranch homes with original Demilec retrofits, newer builds with hybrid foam-and-blown systems, and the thermal stress of 90-degree summer days dropping to 45-degree nights - means generic insulation work fails fast here.
Our crew knows Demilec’s product lines from hands-on removal and replacement, not from a distributor brochure. When a Demilec system has reached end of useful life, we pivot to compatible materials from Owens Corning, Johns Manville, Knauf, Rockwool, CertainTeed, Icynene, GreenFiber, or Reflectix - whatever performs best for your specific assembly. Every job closes with a Documented Photo Record, published blower-door numbers, and the 365-Day Done Right Promise. Calls are answered by a live person, 24/7.
FAQs
No - Demilec’s warranty on installed material expired at original installation completion, and as an independent Demilec service provider, our work carries its own 365-Day Done Right Promise backed by written warranty. Call (669) 280-8103 to review your specific coverage.
We source compatible blown-in cellulose and fiberglass that meets or exceeds Demilec’s original specifications from our multi-brand supplier network - Owens Corning, Johns Manville, Knauf, Rockwool, CertainTeed, Icynene, Demilec, GreenFiber, and Reflectix. True Demilec-branded blown-in stock is limited since the line’s 2023 restructuring; we disclose the exact manufacturer and product on your written scope before work starts.
Repair is cheaper only when the material is dry, uncompressed, and the air barrier is intact - roughly 20% of the Morgan Hill Demilec jobs we inspect. Most need partial removal to access and seal leaks, then top-up or full replacement. We’ll show you the blower-door numbers and photos so you can decide from evidence, not pressure. Free estimates at (669) 280-8103.
Most attic top-ups and dense-pack wall jobs finish in one day; full removal-and-replacement jobs with air sealing typically take two days. We schedule within 48 hours of your call, and a live person answers (669) 280-8103 24/7 to book your slot.
Yes - on any job where air sealing is performed, we provide before-and-after CFM50 readings. This is standard practice for us, not an upgrade. You’ll receive the documented record with your photos and written warranty at job close.
Written by Wes Okafor, Owner & Lead Insulation Technician, Topside Attic Insulation Morgan Hill at Topside Attic Insulation Morgan Hill, serving Morgan Hill and nearby areas.