Moisture question with rigid Insulation on interior of poured concrete basement walls.
I know this question may have been beaten to death, but I haven’t been able to find this specific details in any of the posts on here yet.
I have a basement with poured concrete walls that have a slight moisture issue (they weep very slightly in spring and fall when it rains excessively). So I know that I’m supposed to insulate them using EPS, PolyISO or closed-cell spray polyurethane foam and then build my walls on top of the insulation. I also understand that I should NOT use any vapor barrier so that the moisture doesn’t get locked in.
But my question is, what happens to the water that weeps/wicks through the walls and settles between the wall and the rigid insulation? Won’t mold eventually form at that juncture? Or are these types of insulation permeable enough to allow for eventual drying (it doesn’t seem like they are to me).
When we moved into the house, the owners who originally bought the house back in 1954 had put up tar paper, then furring strips, then T1-11 sheeting to create finished walls. When I pulled them down the backside of the tar paper had some mold on it so I know water had been getting through the foundation walls.
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