How to Insulate Above T&G Ceiling?
We are trying to insulate a vented attic in a single-story cottage which has southern yellow pine tongue-and-groove as a ceiling in the living space. We live in central Massachusetts, zone 5.
We have purchased gaskets from Conservation Technology (which we learned about here, thank you very much) and have stapled them to the ceiling (attic side) against the ceiling joists. Then we screwed down 3/8th inch plasterboard between the ceiling joists. On top of the plasterboard will go three layers of unfaced fiberglass batts, each layer perpendicular to the last layer.
We are wondering:
1) Will the plasterboard screws allow air leakage and do we have to seal & caulk each screw? (Please say it isn’t so; we are 64 years old and wondering if we will survive to insulate the basement & crawl space);
2) Will the gasket beneath the plasterboard be air tight or do we have to seal the plasterboard to accept caulking & caulk along the gap where the joists meet the plasterboard? (Ditto)
We are sticking with the least aromatic/non-toxic elements because we learned the hard way — back in January when this project began — that I stop breathing when exposed to the smallest amount of any type of foam. Will be using AFM caulk because I don’t react to it, but it requires the plasterboard be sealed first.
Hoping someone has been here/done this and knows the answer. Thanks & Regards, Art & Deb
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