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Poly vapour barrier on first floor ceiling or seal the rim board?

user-6893003 | Posted in Green Building Techniques on

I’m installing or polyethylene air barrier on the inside of our walls. Marine 4 zone.

I had thought most people would install the poly on the ceiling of the first floor versus sealing to the top plate and air sealing the rim board. trouble is I’m dreading sealing around all the pot lights with boots as it seems like a great deal of trouble. 

would be it more effective to seal my wall poly to the top plate and caulk my rim joists, stuff with a couple layers of rigid foam and caulk the edges? 

it’s a small building and I have to hit 2.4 ACH per code here. Any tips would be a great help as I haven’t done this in 15 years and we did it very differently back then. 

Part 2, what kind of poly boot should I use to enclose the light and it’s separate junction box? All I really see are boots for  1 or 2 gang boxes or huge ones for old style can lights. I will be doing this in the attic, but may also do it on the first floor ceiling if recommended. 

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