I know this has been debated, but I am just curious as to some more outlook on the best option here. I just ripped out a bathroom with one exterior wall. The wall was insulated with foil-faced fiberglass batts — after ripping them out I saw they had mold on the side contacting the house sheathing. The home is 100 years old — wood sheathing with stucco outside.
I have already created an unvented cathedral ceiling (using 2″ of closed cell spray foam followed by fiberglass batt and 2″ of rigid foam for thermal bridging). Any advice on the best way go about insulating the walls? I will be covering them with cement board, Kerdi membrane, and tile.
Spray foam for this wall isn’t an option…. rigid foam + fiberglass? fiberglass alone?
I am in climate zone 4a….
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