Cardinal Insulation

Open-cell: About R-3.6 per inch
Closed-cell: About R-6.5 per inch
Occupied rooms: Thermal barrier, usually gypsum
Two inches: An air seal, not the finished R

When commercial spray foam is the job

Spray foam goes on the roof deck when that space should be inside the building. It is the right call for a hot roof over an office, a bonus space, or a warehouse that should not stay a vented attic. It is the wrong call for a vented attic whose ceiling is already the boundary. That attic gets blown-in.

Open-cell is about R-3.6 per inch and vapor-open. Closed-cell is about R-6.5 per inch, and at roughly 1.5 to 2 inches it is also a vapor retarder, depending on the product. Two inches of closed-cell is about R-13. That is an air-seal coat. It is not the R-38 attic number, and it is not the above-deck roof number.

Fire barrier

Foam left exposed to an occupied room needs a thermal barrier, usually gypsum, unless the exact product is approved without one. Foam in an attic or a crawl space that is not occupied can use an ignition barrier, or a system listed for that exposure. Bare foam because the schedule ran out is not a finished commercial job.

Foam smells while it cures. The building has to be empty of people who cannot leave the smell. We say so before the day is booked. A store that stays open is not a foam day.

One boundary

Do not foam the deck and leave the attic vented. Pick the deck or the ceiling. A mixed assembly wets the deck. A roof leak is fixed before foam goes on it. Foam is not a roof repair.

Commercial spray foam insulation

When commercial spray foam is the job

Fire barrier

One boundary

The other commercial jobs

Commercial spray foam insulation by city

Tell us the house. We'll call you.