• You're one step from joining Insulation Forum – Home Energy Efficiency, Soundproofing & Materials.
    Create a free account to post, follow threads, and never miss an update.  Sign up free →

tearing out the old cellulose panels in the basement

thec00l bill

Member
Joined
Oct 3, 2025
Messages
8
I’ve been asking my grandpa to let me fix his basement, and finally, a few days ago, he told me that I can do it.
I'm looking at this insulation the builder slapped in there and thinking, Nope!

The whole basement is wrapped in these thick 2 inch cellulose panels. They're basically glued to the concrete walls and sitting right on the floor. It looks like a giant sponge wrapped around the whole space.
I told my pops we gotta rip this junk out and replace it with closed cell spray foam.
Am I being overly cautious here? I keep picturing these panels just soaking up moisture and becoming a mold factory behind the new drywall.

Has anyone dealt with this kind of cellulose panel insulation before, and do you agree it needs to go?
I’m thinking about replacing it with closed cell PU spray. Let me know what you think?
 
I helped redo my uncle’s basement last year and we found mold behind similar cellulose panels. Switched to closed cell spray foam and it’s been dry ever since. You’re not overthinking it, those panels trap moisture like crazy.
 
Yup, definitely right to be cautious, those panels trap moisture fast, and once drywall goes up, you won’t know what’s happening behind there. Closed cell spray is a very good upgrade
 
Phew, thanks for the validation, guys! That giant sponge feeling was really stressing me out. It sounds like the closed cell is the right move for long term dryness.

so, since I'm tearing out the old stuff, what's the best way to make sure the wall is 100% ready for the foam? should I run a dehumidifier for a few days straight after ripping the panels off, or is a simple visual check enough before starting the spray?
 
Running a dehumidifier for a few days is def a smart move, especially if the wall has been holding moisture and sometimes with these you might not know, so even if it looks dry, give it time to dry thoroughly, then do a visual and touch check before spraying
 
You are right to be worried. Celluose next to concrete could trap moisture and cause mold if it is glued directly to the wall. The smart move is to tear it out and use foam (spray or rigid) which is safer for a basement in the long run.
 
Back
Top