I am buying a house with vaulted ceilings and I’m in climate zone 5 near zone 6. I am planning on installing at least 3″ of XPS over the existing drywall on the ceiling and then adding another layer of drywall over that. The current roof is 2″ by 6″ and has fiberglass bats installed and has roof vents but the soffits are not ventilated well. The roof will need to be replaced and the sheathing as well. Do I need to worry about installing something like SmartBaffles or just leave as is and make sure the foam insulation I install is airtight? Would it be better if it wasn’t vented at all? If I install the smart baffles then I’m assuming I want to install them the whole length of the rafters and put in a ridge vent? I’m worried about ice damming and whether the sheathing will retain moisture leading to rot or mold. It does have one dormer for the front porch, otherwise is just a simple 3/12 roof. Thanks in advance for any advice you can give, Erik.
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