Air-Sealing a Tongue-and-Groove Ceiling from the Attic
I’ve got a vented attic above a 950 sq ft area. Just over half the area is normal joisting with drywall. Above the Master Bedroom (16′ x 21′) is a Tongue and Groove Ceiling that is supported with large timbers from the inside. So in the attic I’ve got a this whole area flat, no joists to work around. It currently has R-11 batts on top of it. I want to blow in insulation in the whole attic. What’s the best way to air seal the tongue and groove section? I’m thinking Tyvek Home Wrap or Homegaurd brand. Would remove all those old batts, roll out the Tyvek. Tape any seams. Not sure the best way to secure it down. Capped nails all seem to long. Maybe just staples and tape over after. Or just roll the whole length and secure at ends and not worry since I’ll be covering it with cellulose.
Should I instead use a smart vapor barrier?
Hard to tell but it’s also sloped and a fall off at the end so I’ll have to build an insulation dam for the area.
It’s a low slope roof if that means anything. If I remove the batts, I should not reinstall them correct so I don’t trap moisture between the batting and the air barrier I put down correct? Build dams and blow in cellulose?
Other idea to shoot down, what if I just put the wrap overs the existing batts and secure it down with tape sealing it like one big pillow, get whatever R value that provides and then do the blow in on top of that? Only concern would be potentially trapping moisture in the batts or not worrying because it’s fiber glass and the breathing through the gaps in the batts and the tongue groove are adequate.
Included 2 pics of the rest of the attic in case anything stands out.
In Zone 5 – Northern NJ.
Thank you in advance.
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