Demilec Spray Foam Insulation in Santa Clarita: What to Know First
We provide independent Demilec spray foam insulation in Santa Clarita, typically completing most jobs same-day or next-day with a written price locked in before any work starts. Most Demilec open-cell and closed-cell foam jobs in a Santa Clarita home this size run between $2,800 and $6,400 depending on cavity depth, square footage, and whether we’re treating a roof deck, rim joist, or garage ceiling. This page is for homeowners who already have Demilec foam in their building envelope and need service, retrofit, or replacement from a crew that knows the product line cold. Call (747) 294-2764 for a free estimate with a written scope delivered before anyone lifts a tool.
How Demilec Products Fail - and How We Fix Them
- Demilec Heatlok HFO Pro closed-cell shrinkage at rim joists. The HFO blowing agent in this series can pull away from sill plates in Santa Clarita’s dry Santa Ana cycles, especially in older two-stories near Valencia Town Center where the rim joist sits above a vented crawl space. We cut back the separated foam, reseal the wood-to-concrete joint with acoustic sealant, then reapply in lifts no thicker than 2 inches to prevent exotherm cracking.
- Demilec Sealection 500 open-cell overspray into soffit vents. Sealection’s expansion ratio is aggressive, and in tight Santa Clarita attics with 4:12 roof pitches, it can block intake ventilation. We remove the obstructed foam with a specialized hot knife, reinstall baffles, and re-foam with a dam at the eave edge to maintain the 1-inch code-required air gap.
- Demilec Heatlok XT low-density closed-cell surface degradation in garage ceilings. XT’s skin is thinner than competing closed-cells, and in unconditioned Santa Clarita garages where summer surface temps hit 140°F, UV through garage door windows can chalk and powder the exposed face. We assess whether a thermal barrier coating is sufficient or if the foam needs encapsulation with an ignition barrier paint rated for California Title 24.
- Demilec Sealection Agribalance odor retention in agricultural-adjacent homes. The bio-based content in Agribalance can trap organic off-gassing when installed over damp OSB in Saugus and Canyon Country homes near former ranchland. We test substrate moisture with a pinless meter, dry the deck with targeted ventilation if readings exceed 19%, then reapply only after the sheathing passes.
- Demilec spray foam disbonding from polyiso board in hybrid assemblies. Some Santa Clarita contractors layered Demilec closed-cell over existing polyiso in retrofit jobs, and the incompatible surface chemistry causes delamination. We strip to substrate, apply a tie-coat primer rated for both substrates, then re-foam with a documented adhesion pull-test on a sample patch before full application.
Our Demilec Spray Foam Insulation Process

- 1
Call and scope. A live person answers, schedules a site visit, and sends a text with your technician’s name and ETA.
- 2
Blower-door test and moisture mapping. We pressurize the house to measure baseline air leakage, then scan substrates with a thermal imager and pinless moisture meter. Wet wood gets dried before foam touches it.
- 3
Written price and material spec. You get a flat price, the specific Demilec series or compatible alternative we recommend, and the warranty terms in writing. No work starts without your signature.
- 4
Air sealing first, then foam. Top plates, can lights, and penetrations get sealed with acoustic sealant or expanding foam before the Demilec rig arrives. We never blow insulation over an unsealed attic floor.
- 5
Installation in controlled lifts. Closed-cell goes on in 2-inch passes; open-cell in 3.5-inch passes. We monitor substrate temperature and ambient humidity, both of which shift fast in Santa Clarita’s canyon microclimates.
- 6
Post-job blower-door test and documentation. We pressurize again, print the before-and-after CFM50 readings, photograph the completed work, and deliver both with your invoice. The report goes home with you. The numbers don’t lie, and you shouldn’t have to take anyone’s word for it.
Before
AfterWhat Demilec Spray Foam Insulation Costs in Santa Clarita
| Job Type | Typical Range | What Moves the Price |
|---|---|---|
| Garage ceiling, Demilec closed-cell (2 inches) | $2,800 - $4,200 | Bay count, ignition barrier requirement, existing foam removal |
| Attic roof deck, Demilec open-cell (5.5 inches) | $4,500 - $6,400 | Roof pitch complexity, need for baffle installation, access constraints |
| Rim joist, Demilec closed-cell (3 inches) | $3,200 - $4,800 | Linear footage, crawl space clearance, shrinkage repair vs. new install |
| Demilec foam removal and replacement | Add 40-60% to above | Depth of existing foam, disposal fees, substrate remediation |
Prices include material, labor, the blower-door test, and the Documented Photo Record. We also source from Owens Corning, Johns Manville, Knauf, Rockwool, CertainTeed, Icynene, and GreenFiber if a different material suits your assembly better. Call (747) 294-2764 for your written price - estimates are free, and we offer a Free Second Opinion on any competing written estimate.
Why Santa Clarita Homeowners Call Topside Attic Insulation Santa Clarita for Demilec Work

We’ve sealed and insulated over 9,000 homes since 2016, and the Santa Clarita Valley has been a core market for years - from the ranch houses in Stevenson Ranch to the two-stories climbing the hills above Sand Canyon. Wes Okafor, who trained in building science at Washburne Trade School in Chicago, runs every job with the same standard: air seal first, test before and after, document everything. Our technicians are background-checked and uniformed, and calls are answered by a live person 24/7. If we install it and it’s not right, the 365-Day Done Right Promise means we make it right. We also service Reflectix and other radiant barrier systems when a hybrid approach makes more sense for your envelope.
FAQs
No - Demilec’s product warranty covers manufacturing defects regardless of who installs it, though improper application can void coverage. We document substrate conditions, lift thickness, and environmental readings during installation so there’s a clear record if a claim ever arises. Call (747) 294-2764 and we’ll walk you through what’s documented and why it matters.
We source Demilec products directly through authorized distribution channels, and we also specify compatible formulations from Icynene or other manufacturers when the building science supports it. You get the material spec in writing before we start, with no proprietary lock-in. For a material comparison on your specific job, call (747) 294-2764 for a free estimate.
Localized shrinkage or surface degradation can often be spot-repaired for 30-50% less than full removal, but only if the substrate is sound and the remaining foam passes an adhesion test. If moisture has compromised the wood beneath or if the foam was installed in lifts too thick and is cracking throughout, removal and reinstallation is the only durable fix. We test and give you both numbers in writing. Call (747) 294-2764 to schedule an assessment.
Most residential jobs are completed in one day; larger roof deck treatments or jobs requiring extensive dry-out may run two days. We schedule within 48 hours of your signed written price, and you’ll get a text when your technician is en route. For next-available scheduling, call (747) 294-2764.
Yes - every applicable job gets before-and-after CFM50 readings printed and delivered, regardless of the magnitude of change. Sometimes the starting leakage is already low and the improvement is modest; sometimes we find a disconnected duct or missing damper that drops the number more than foam alone. Either way, the report goes home with you. The numbers don’t lie, and you shouldn’t have to take anyone’s word for it.
Written by Wes Okafor, Owner, Topside Attic Insulation Santa Clarita at Topside Attic Insulation Santa Clarita, serving Santa Clarita and nearby areas.