Doubling exterior walls in rehab, moisture concerns
This question is similar to the post here:
(https://www.greenbuildingadvisor.com/question/retrofitting-new-wall-inside-existing-frame), but is a bit different. I have a newer brick facade house with existing faced R13 insulation and existing drywall. I would like to add another wall on the inside of all exterior walls, and I would like to stay away from spray foam/foam board as much as possible.
My preference would be to leave the existing drywall and vapor barrier (the facing on the existing insulation) and simply build my second wall, insulate it, install vapor barrier and drywall and be done. Am I asking for moisture problems by having a double vapor barrier and the potential for moisture to be trapped between the old wall and the new?
If that were a likely problem, my plan would be the above plus a tear-out of existing drywall and vapor barrier.
I’d love to hear your thoughts… Thanks!
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