Sub slab air sealing
I’m within a month of pouring the footings and basement walls for our house in SW MT (climate zone 6). Plan is for six inches of EPS, stego wrap (or the equivalent) taped and brought up the exterior basement walls and eventually sealed to the wall with closed cell foam. Then a 4 inch slab with embedded radiant tubes.
What I’m not clear on is how to air seal under any interior posts or walls that are load bearing (Ie things in the basement that rest on footings inside the perimeter walls – stairwell footings, posts, walls). Do you somehow bring and tape the poly up around the post or wall and tape it off? Or do you run the poly over the foam (or footing) and the wall just bears on the slab directly, transmitting it’s load through the foam and to the footing?
I have been looking through the detail archive and can’t find a cross section, but methinks the order should be footing, aggregate, foam, poly, slab, and then post. Or asked more simply, do load bearing points in a basement affect the sub slab insulation and air sealing?
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