Vapour barrier for odd insulation order
Hello, first time poster.
I insulated my 16×24 workshop with recycled 4″ XPS(r20 theoretically) in the 3.5″ stud bays + left over foam from a 2 part kit for the gaps/stud faces. This has been fine, but I want to actually finish the interior wall as it’s just the exposed XPS at the moment. My messy spraying would make it difficult to finish so I was going to add an interior stud wall and some extra Fiberglass insulation I had lying around (r14).
Would a vapour barrier/retarder in the form of 6mm poly be needed? I’m going to finish with t&g 5/8th plywood.
Also, I stood the 4″XPS off the exterior siding(no sheathing, just the wood siding) with some 3/4″ strips of wood, but there’s no specific air flow in that cavity.
Also, live near Ottawa. Zone 5 I believe.
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