Poly on the warm side of drywall
I need a question answered, kind of ASAP!
I just acquired a single story 1200 sq ft rental. It has roof trusses, and below the trusses is a drywall ceiling. Below the drywall is a suspended ceiling. As part of an energy upgrade, I am installing 2′ of loose fill cellulose in the attic (ceiling).
We discovered that there was no vapor barrier (poly) above the drywall. No problem EXCEPT the drywall was never taped…or anything! ( I guess hence the false ceiling). No problem except my drywall guy says it will be VERY expensive and time consuming to try and do repairs the drywall. Drywall replacement is not really an option.
So…We came up with a plan to replace the old suspended ceiling with 2×3 nailers below the drywall and then nail some surplus T&G pine paneling to the nailers. I know…this alone does nothing to address the air movement/vapor issues.
My insulation guy thinks we would be ok to put 4-6mil poly between the untreated drywall and the nailers and do a good job of taping the poly to endure no leaks. Combined with the nailers keeping the poly secure, He feels if any moisture got behind the poly it would continue up thru the cracks in the old drywall to the cellulose and up to the cold roof.
Zone 7 7000 HDD.
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