Spray foam’s always been a bit of a gamble for me with old stone or brick. I’ve seen it trap moisture behind the walls, which can get ugly fast—especially in basements that already have a tendency to stay damp. I’ve tried rigid foam panels with tape and, honestly, the tape always seems to peel after a couple years. Ever notice how nothing really wants to stick to those rough, uneven surfaces? I keep wondering if there’s a “best of both worlds” solution that doesn’t mess with the original materials too much...
I hear you on the spray foam—used it once in my old stone basement and regretted it. Ended up with a musty smell that wouldn’t quit, and when I finally opened up a section, there was a patch of black mold hiding behind the foam. Never again. Rigid foam’s a bit better, but like you said, getting tape to stick to rough stone is a losing battle. I’ve tried that “liquid flashing” stuff to seal the seams instead of tape, but it’s messy and still not perfect.
What’s worked best for me is leaving a small air gap between the insulation and the wall. I use furring strips anchored into the stone, then put rigid foam or mineral wool batts between them. That way, if any moisture sneaks in, it’s got somewhere to go and can dry out. Doesn’t mess with the original wall too much, and you can still get decent insulation. Not perfect, but it’s kept my basement from turning into a swamp. Just takes a bit more time to set up, but worth it if you’re dealing with old, uneven walls.
Ended up with a musty smell that wouldn’t quit, and when I finally opened up a section, there was a patch of black mold hiding behind the foam. Never again.
Leaving that air gap really does make a difference, especially with old stone. I tried the same thing after fighting with spray foam and regretting it—mold city. The furring strips and rigid foam combo is a pain to line up, but it’s the only thing that’s kept my basement from smelling like a bog. I do wonder if mineral wool might be better than rigid foam for breathability, though. Ever notice any issues with drafts sneaking in around the edges? I’ve had to go back and caulk a few spots where the air was just pouring through.
Keeping Your Home Dry: Insulation Tips for Flood-Prone Areas
Man, the “basement bog” smell is all too real. I tried to cheap out with just rigid foam pressed up against the wall—figured, hey, what’s the worst that could happen? Fast forward a year and it was like living in a gym locker. I’ve heard mineral wool is supposed to breathe better, but does it actually hold up if you get a little water sneaking in? I’m always worried it’ll just turn into a soggy mess down there.
Drafts are another headache. I swear, I spent more time chasing cold air with a caulk gun than actually insulating. There’s always that one spot you miss, right? I’ve even tried that expanding foam in a can, but half the time it ends up everywhere except where I want it. Anyone else have luck with those foam gaskets or is that just another thing to buy that doesn’t really work? Sometimes I wonder if it’s just easier to move somewhere dry...
I tried to cheap out with just rigid foam pressed up against the wall—figured, hey, what’s the worst that could happen? Fast forward a year and it was like living in a gym locker.
That “gym locker” vibe is the price of skipping the vapor barrier, trust me. Rigid foam’s fine but only if you seal it up tight and keep moisture out from the get-go. Mineral wool’s great for sound and fire, but in a wet basement? It’ll soak up water like a sponge and just hang onto that dank smell. Best bet is to fix drainage outside first, then use closed-cell spray foam—costs more but pays off long-term. Those foam gaskets are okay for outlets, but they’re not magic. Honestly, I’ve seen more basements ruined by shortcuts than by actual floods. Sometimes moving really does sound easier…
