03/25/2026
Open cell vs. closed cell here’s something most people don’t think about.
Open cell spray foam can work in some situations…
But in New England, especially in garages or buildings that aren’t conditioned year-round, it can cause serious issues.
❌ Temperature swings = condensation risk
Garages heat up during the day, cool off at night, and aren’t 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.
❌ Moisture gets trapped
Because open cell is porous, it can actually hold that moisture.
In a garage, this can lead to:
• Damp insulation
• Mold growth
• Wood rot over time
• That musty smell that never goes away
And the worst part it’s all happening behind the walls or roof where you can’t see it.
Now compare that to closed cell:
✅ Stops moisture before it becomes a problem
Acts as a v***r barrier, helping prevent condensation from forming in the first place.
✅ Handles temperature swings
Perfect for garages, metal buildings, and spaces that aren’t constantly heated or cooled.
✅ Doesn’t absorb water
Keeps its performance and protects the structure long-term.
Bottom line:
If your garage or building isn’t conditioned correctly 24/7…
Open cell can create problems you won’t notice until it’s too late.
Closed cell is the safer, smarter choice for those spaces.
