How to handle unvented cathedral/vaulted ceiling
I know there is a lot of healthy debate here, but let me share my situation.
Climate zone 3. 40 year old house I just bought.
I am about to start remodel which includes ripping the cedar wood planks off my cathedral ceiling and replacing with drywall. The current construction is Cedar lap siding, craft paper barrier, backed fiberglass insulation filling the cavity 2×8 cavity, roof sheathing, asphalt shingles. No airflow/ventilation.
The way the room is constructed putting in vents is not an option. There is a large skylight dormer on one side and the other side does not terminate to the outside. So there are no soffits. The current construction has not seemed to fail but I haven’t fully demoed yet.
I am tempted to just take the cedar planks down, put a smart vapor barrier up like membrain seal up the drywall as tight as possible. Second best option is to spring for closed cell spray in.
I’d appreciate all thoughts. Hopefully ideas that do not require me to tear my house down and rebuild.
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