Owens Corning Attic Air Sealing Nationwide

Owens Corning Attic Air Sealing: The Mountain View Owner’s Guide

Most Owens Corning attic air sealing jobs in Mountain View run between $1,800 and $3,400 installed, depending on attic square footage and how many top plates, can lights, and duct penetrations need sealing. We stock Owens Corning FOAMULAR rigid foam board, ProPink sealing products, and compatible one-part polyurethane foam on every truck, and we can typically inspect and start same-day if you call before noon. Homeowners usually figure out something’s wrong when their upstairs rooms won’t stay cool in August despite the AC running nonstop, or when they pull back insulation in the attic and find it blackened with dust trails - the telltale sign that conditioned air is escaping through gaps the sealing was supposed to close.

Call (669) 259-0406

Which Owens Corning Models This Applies To

Owens Corning doesn’t sell attic air sealing as a single named “system” the way they sell insulation batts by R-value. What you’re looking for is the combination of FOAMULAR 150 or 250 rigid foam board, ProPink sealants, and Owens Corning-certified one-part foam used to seal the thermal envelope before insulation goes in. If your home was built between 2015 and 2025 in Mountain View, there’s a decent chance the original builder used Owens Corning materials for the insulation package but skipped proper air sealing at the top plates and electrical penetrations - we see this in the Rex Manor and Monta Loma neighborhoods regularly.

To identify what you’ve got, check the attic for pink-labeled batts or blown-in fiberglass; Owens Corning insulation is color-coded pink. The air sealing components themselves are rarely labeled by brand once installed, but FOAMULAR board will have a printed facing with density rating. For retrofits, we match the existing R-value and thickness - typically 1-inch or 2-inch FOAMULAR for blocking, cut to fit between trusses at the attic perimeter. Aftermarket equivalents exist, but Owens Corning FOAMULAR has a consistent 25 psi compressive strength that cheaper XPS boards don’t always hit, which matters if your attic gets used for storage or HVAC access. We carry both OEM and spec-matched alternatives on the truck and will show you the difference before we cut anything.

Signs Your Owens Corning Attic Air Sealing Is Failing

• Dust-blackened insulation near the attic hatch or eaves. This means air is moving through the material, carrying filter-trapped dust from your living space. Clean insulation stays pink or yellow; black streaks are a map of every leak the sealing missed.
• Upstairs rooms that run 8-12 degrees warmer than downstairs in summer. In Mountain View’s climate, this isn’t normal. Hot attic air is pulling conditioned air out through ceiling penetrations faster than your ducts can replace it.
• Ice damming or heavy frost on nails protruding through the roof deck in winter. Warm, moist air hits cold metal, condenses, and freezes. The sealing around plumbing stacks and vent boots has failed, or was never done.
• Can lights that flicker or run hot. IC-rated can lights should be sealed to the drywall; non-IC cans need a sealed box over them. When that seal breaks, heat from the bulb meets attic air, and the fixture overheats.
• Your blower-door test from the original build read over 3,500 CFM50. That’s loose for a 2015+ home in California. We recently tested a 2019 build in Cuesta Park that hit 4,200 CFM50 - the builder had insulated over unsealed top plates, and the homeowner had been paying to heat their attic for four years.

Replacement Cost & What’s Included

In Mountain View, a complete Owens Corning attic air sealing job typically breaks down as follows:

What drives the range: attic accessibility (scissor truss vs. conventional), quantity of can lights and penetrations, and whether we’re working around existing insulation or removing it first. We don’t blow new insulation over failed sealing - that’s sealing the problem under a pink blanket. Every job gets a written price before we start, a Documented Photo Record of every penetration sealed, and before-and-after blower-door numbers so you can verify the ACH50 improvement. The 365-Day Done Right Promise covers all workmanship; material defects fall to Owens Corning’s product warranty, which we handle the paperwork for.

DIY or Call Us?

There’s a short list of things a homeowner can safely check: pull back insulation at the attic hatch and look for gaps where drywall meets the top plate, shine a flashlight around can lights for visible gaps, and note any spots where insulation looks disturbed or compressed. What you find is useful information to tell us when you call.

What you shouldn’t do: crawl around a truss attic with a can of hardware-store foam and hope for the best. Proper air sealing requires knowing which penetrations are structural (leave them alone), which are electrical (fire-rated caulk, not generic foam), and how to maintain attic ventilation pathways so you don’t trap moisture against the roof deck. We’ve found DIY foam jobs in Mountain View that blocked soffit vents and created condensation pockets - one homeowner in Old Mountain View had rot in his rafter tails two years after a “simple” weekend project. We also stock and install Reflectix radiant barrier products where appropriate, but never as a substitute for proper sealing. Call (669) 259-0406 and we’ll walk through what you found; estimates are free, and we bring the right foam, the right caulk, and the right fire-stop materials for your specific penetrations.

FAQs