03/25/2026
Open cell vs. closed cell hereโs something most people donโt think about.
Open cell spray foam can work in some situationsโฆ
But in New England, especially in garages or buildings that arenโt conditioned year-round, it can cause serious issues.
โ Temperature swings = condensation risk
Garages heat up during the day, cool off at night, and arenโt always climate controlled.
That constant change creates condensation.
Open cell is not a v***r barrier, so moisture can pass right through it and when it hits a cold surface, it turns into water.
โ Moisture gets trapped
Because open cell is porous, it can actually hold that moisture.
In a garage, this can lead to:
โข Damp insulation
โข Mold growth
โข Wood rot over time
โข That musty smell that never goes away
And the worst part itโs all happening behind the walls or roof where you canโt see it.
Now compare that to closed cell:
โ
Stops moisture before it becomes a problem
Acts as a v***r barrier, helping prevent condensation from forming in the first place.
โ
Handles temperature swings
Perfect for garages, metal buildings, and spaces that arenโt constantly heated or cooled.
โ
Doesnโt absorb water
Keeps its performance and protects the structure long-term.
Bottom line:
If your garage or building isnโt conditioned correctly 24/7โฆ
Open cell can create problems you wonโt notice until itโs too late.
Closed cell is the safer, smarter choice for those spaces.
