Placement of WRB when it is also your drainage plane
This is Asaf from SF Bay Area Climate zone 3B, just over 20″ of rain yearly here.
After much back and forth with my contractor (who happens to be my father in law- ie I can’t push him beyond a certain point before I put familial relations in danger) we have agreed to use “alternative” approach to drainage plane. He has never installed furring strips and doesn’t intend to now. He is open to installing foam with posterior grooves or a housewrap such as Hydrogap to improve drainage of system (will likely combine with grade D paper). Relevant details include conventional stucco finish, innie windows, 1.5″ of polyiso (though can substitute EPS- easier to find with grooves) that will be taped
Usually, with innie windows I know I should install WRB beneath foam, but given one layer of my WRB will function as a drainage plane, should I do something different? I would think drainage plane should be just underneath stucco, but Benjamin Odyke gives option to put it behind foam too-seems like a waste if one tapes the foam. I also wonder if stucco wouldn’t just bond to the housewrap and negate the drainage properties unless grade D paper installed over the Hydrogap.
I am attaching reference materials from Benjamin Odyke.
Appreciate any assistance.
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