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Outie window, polyiso, rainscreen details?

Wunderbar | Posted in General Questions on


I started working out my window details. I’ve got 1/2” zip taped sheathing with an outie window buck. Paper backed polyiso with 3/4” rainscreen furring strips. My question is do I need to put an additional wrb over the polyiso or can that stuff get wet and dry out? Not sure exactly how to flash the window without a wrb to tape to?

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  1. Expert Member


    My understanding is that foil face polyiso can be used as a WRB, but not the paper backed. So your options are to flash back to the Zip, or add an additional WRB.

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