Drywall instead of osb as vapour retarder/air barrier on ceiling with service cavity
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I see a lot of osb used to make a vapour control layer and air barrier on the ceiling then furring down 1.5″ for a service cavity. Can a person use drywall and tape to achieve the similar results? I don’t know if the seam tape is rated for drywall but it should achieve the same result.
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Replies
You may need to add vapor retarder paint to get the perms you need. Or a smart membrane.
thank you. Would be a safe way to add a little insurance to the assembly.