Spray foam is applied as a liquid that expands on contact, filling every crack, gap, and cavity it touches, then cures into a solid air seal. It comes in two types, open-cell and closed-cell, with different performance, cost, and best-use profiles. We install both, and we'll tell you honestly which one your project actually needs.
The right product depends entirely on where it's going and what job it needs to do. We assess that for free before recommending either one.
| Factor | Open-Cell | Closed-Cell |
|---|---|---|
| R-value per inch | 3.5 | 6–7 |
| Cost | $1.85–$2.30/sq ft | $1.85–$2.00/sq ft/in |
| Vapor barrier | No | Yes |
| Soundproofing | Excellent | Good |
| Water resistance | Poor | Excellent |
| Works on metal surfaces | No | Yes |
| Best for | Interior walls, basements, soundproofing | Exterior walls, attics, crawlspaces, humid areas, metal buildings |
For Georgia's hot, humid climate, we lean toward closed-cell on exterior walls, conditioned attics, and crawlspaces because it doubles as a vapor barrier. Open-cell is the right call for interior walls and soundproofing, where its lower cost and better sound-dampening are the priority. We'll tell you which one makes sense for your specific project, not just sell you the more expensive option.
One hard rule either way: open-cell foam cannot be applied to metal surfaces. If you're insulating a metal building, pole barn, or metal roof deck, closed-cell is the only option, see our commercial insulation page for more on that.
Expands to fill every crack and gap, stopping drafts and energy loss at the source, something loose-fill insulation can't do on its own.
Flows around pipes, wiring, and odd framing that rigid board insulation simply can't reach.
Bonds to framing and adds real wind resistance, a genuine benefit during Georgia storm season.
Unlike loose-fill materials, spray foam holds its shape and R-value for the life of the home.
Closed-cell foam in particular is dense enough that insects and rodents have a hard time getting through it.
Fully hardened spray foam (24–48 hours) is completely inert, with no ongoing fumes or chemicals in your home.
We suit up in protective gear, seal off the work area, and apply the foam in careful passes, thinner passes for closed-cell to prevent overheating and cracking, which is a shortcut some contractors take that we never do. The foam expands and cures within minutes, and we trim it flush with framing so drywall or paint can go right over it.
You, your family, and pets will need to be out of the home for at least 24 hours while the foam finishes curing and any fumes clear. We'll confirm the exact all-clear time before we leave, no guessing.
Some contractors spray closed-cell thinner than spec to save on materials. We measure and document thickness on every job, about 2 inches is needed to properly insulate a standard wall, and we never cut that short.
Open-cell runs $1.85–$2.30 per sq ft depending on thickness. Closed-cell runs $1.85–$2.00 per sq ft, per inch, since it's usually applied thinner to hit the same or better R-value, total project cost is often comparable to open-cell despite the higher per-inch price. Actual cost depends on square footage, thickness needed, and accessibility. We give you an exact, itemized quote after a free assessment.