Pouring concrete against OSB sheathing (SIP) and pressure treated mudsill
Hello all, I’m a first time house builder running into what I don’t think should be difficult and I am likely over thinking it.
We are building a SIP encapsulated, timber frame home in northern Alabama (climate zone 3) that will have a traditionally framed floor (mud sill, 2x joists, etc.) resting on pre-cast Superior Walls. We have a covered patio that will be poured concrete up against the house. I have concerns about trapping water against the wood, creating a breeding ground for termites, and probably other terrible things I haven’t thought of yet. See attached drawings for more detail.
My thought right now is to use some kind of peel & stick membrane (PolyWall Home Strech, Grace Bithuthene, etc.) covering the OSB from a few inches above concrete down over the pre-cast concrete wall to the stone ledge. Then in front of that to place a 1/2″ or 1″ expansion joint (like this: https://www.nmwinc.com/files/2019-08-15_07_02_51_nmw_rebondedrubber_-_copy.pdf51c9d4d5.pdf) running the full height from the Superior Wall stone ledge up to T.O.C.
Any thoughts on that? Or is there some standard assembly or other product I’m missing for this?
I’m assuming this comes up with people pouring adjacent to mudsills and sheathing all the time, so I’m probably missing the obvious solution(s) here.
Thanks for any ideas/help,
GBA Detail Library
A collection of one thousand construction details organized by climate and house part