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Discussion Starter #1
I’m finishing my basement, in which the exterior walls were already studded out and drywalled. From my understanding (from doing some electrical work pulling wires) there is the block, styrofoam?, stud, the drywall finish. Now my laundry room was never studded and drywalled only foam put on top half of wall I assume like every other exterior wall in my basement. For aesthetic purposes I have torn off the foam in hopes of sealing/priming and painting the block however upon removing foam I’ve found the block is wet to touch and damp. Should I be very concerned or is this relatively normal porous block behavior? The bottom half had already been painted and I’ve never noticed any water running down the wall, I’m assuming because the adhesive they used on the foam stopped it. Should I go ahead and seal? Worried about every exterior wall in my basement molding..
 

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You aren't alone because there are thousands upon thousands of basements just like yours, but you are one of the few that has discovered the mistake that was made by insulating the area internally. Even though you weren't the one that made the mistake you are the one to deal with it as the thousands of others eventually will.

I'm anticipating the experts solution as well as you.
 

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retired framer
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Water proofing or water resistant coating is done on the outside along with a perimeter drain around the outside to move water away from the foundation.
When that fails concrete can wick thru the concrete to the inside. If the wall is sealed on the inside, it will usually find another way in or just fill the block wall interior with water.
We don't see evidence of that.
I think the insulation was keeping the wall cool but did not stop warmer moist air from getting behind it where the water could condense on the wall.
Give that some time to dry.
Foam like that can be used on the foundation wall but it has to be sealed and taped and treated like a vapour barrier so moisture from the house can not get behind it.
 

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Discussion Starter #4
The wall is already drying up, I’ll put some dry lock paint on it and finish it. Should I be worried about my other walls?
 

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retired framer
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The wall is already drying up, I’ll put some dry lock paint on it and finish it. Should I be worried about my other walls?
The test when dry would be to tape a piece of sheet poly to the wall and make sure it is sealed and the cover that again with foam for a while.
Wet behind the poly is coming thru the wall wet on the outer surface of the poly is coming from the basement.
If they built walls and drywalled them they may have changed the construction style and insulation type. Here it would have been sealed with vapour barrier but if it wasn't I would not expect that you have a lot of air movement from the basement to the outer wall. Next time you are doing some drywall repair in the house cut a hole near the floor and see if there is any evidence of water in there.
 

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xypex is a MUCH better material,,, applied properly, you'll only have to coat the wall once,,, wet AWAYS runs to dry so consider a dehumidifier set to 45%
 
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