Here is the issue, my basement wall facing south is trapping moisture. Removed the drywall and found a layer of poly and rigid insulation on the lower wall and batting insulation on the top side. The 2×4 framing studs are built above the footing blocks but on the inside they put 1×6 furring strips and drywall over that The exterior brick wall under the window shows efflorescence. Btw, my footing is above grade.
Would this have been caused by water/moisture from the exterior brick wall/ window or internally from the vapor barrier?
I've read too much information about basement wall insulation and some say to insulate it some say don't.
any help or information greatly appreciated.
Best Answer
The correct way to insulate a basement wall is with rigid foam or spray foam right up against the masonry walls, with air sealing scrupulously done with caulk, tape, and more spray foam, to make sure that no humid air can touch the masonry walls. Once that's done, you can safely build a framed wall covered in drywall if you like to finish the space. There should NEVER be poly in this wall sandwich, as it will trap water and cause everything touching it to get wet.
If you currently have a wall that has poly anywhere in it, you need to remove it. Then redo it according to the above description.