Air barrier on cape w loft
I’m having trouble deciding on how to best go about installing the air barrier on our project that is currently in the design stage. Zone 5, cape style, single story with loft. Simple roof without dormers.
The wall will be double stud with blown in cellulose, with the plywood acting as the air barrier. Currently I am thinking that the lower 2/3rds of the rafters will be the loft space, and the upper 1/3rd will be a vented attic with blown in cellulose on the deck.
The lower 2/3 of the rafters will likely also have to be double stud to achieve sufficient R value, and to accommodate the space for the vent channels, which will start at the soffit.
My question is, has anyone here run into a similar situation, and what did you come up with?
Lately I have been considering taping the corner from the external first floor sheathing to the plywood on top of the lofts floor joists. From the plywood on the inside of the rafters, I was thinking of taping something like intello and running the membrane up and under the collar ties / attic floor joists. Inside of the intello, perhaps a service cavity for simplifying the detailing when installing whatever lighting is decided upon.
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