Smart vapor barrier vs drywall under shiplap ceiling
New build in CZ 6. Have a very tall cathedral ceiling that will be flashed with 4″ CCSF and then R23 rockwool batts. The finished ceiling in this room will be tongue and groove pine.
The exterior walls and other ceilings in the home will have a smart vapor barrier. However, I’m wondering which makes the most sense to put under the tongue and groove ceiling?
A smart vapor barrier would definitely be easier to install but less burly. A drywall ceiling under the T&G would be a lot to manage but certainly more solid feeling.
As a note — there will be no recessed or pancake lights in the ceiling at all.
Thanks for any insights on what makes sense here–
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Replies
Sean,
The chief benefit of both drywall or a membrane in a flash & batt roof is as a good warm side air-barrier. Their qualities as vapour-retarders are very secondary. I'd go with the membrane.