Open-cell foam is made of cells that stay open, giving it a soft, flexible texture. It's about 0.5 lb/ft³, expands roughly 3 inches, and can be sprayed 8–10 inches deep in one pass.
Best for: interior walls, sound control between rooms, and projects where budget matters more than a moisture barrier.
Open cell · roof decks
Closed-cell foam has sealed cells — think of a truck bed-liner. It's about 2 lb/ft³, denser and more rigid, and it does more than insulate.
Best for: metal buildings and barndominiums, exterior walls, tight cavities, and anywhere moisture control or extreme temperatures are in play.
Closed cell · dense foam
| Property | Open Cell | Closed Cell |
|---|---|---|
| R-value / inch | ~3.7 | ~7.6 |
| Density | ~0.5 lb/ft³ | ~2 lb/ft³ |
| Expansion | ~3 inches | ~1 inch |
| Max spray depth (per pass) | 8–10 inches | ~3 inches |
| Moisture / water barrier | No | Yes |
| Adds structural strength | No | Yes |
| Soundproofing | Excellent | Good |
| Relative cost | Lower | Higher |
The right foam depends on your building type, your climate exposure, how much depth you have to work with, and your budget. We'll look at the space and give you a straight recommendation — including when the cheaper option is genuinely the smarter one.
Tell us about your space and we'll give you an honest recommendation and a written quote — no obligation.
