i have an old cement wall house, i have tar paper on the outer walls and plan on putting 1 or 1 1/2 thick ridge insulation on the walls. These are above grade walls not basement.My question is do i have to vapor barrier the walls or just tape the seams of the foam insulation.thanks in advance
If you already have tar paper (roofing felt, I presume), thats a vapor barrier. You don't need another. You can caulk the joints between the boards if you'd like.
