Board-formed concrete wall
Finally began with the construction of our 6000 sq’ home in Central Texas. Still working on the pad for the monolithic slab foundation. The geotechnical engineer wants it to be overbuilt 10′ beyond foundation edges, which I have been told is way overkill by the local builders and the pad contractor who has been swearing at the geotechnical engineer everyday…Any thoughts on this. Our PIs were 30 on the soil test.
My main question has to do with the board formed concrete walls. 4 of the exterior walls are supposed to be done this way. I understand that we should put 2″ XPS foam (or equivalent) inside for insulation. My question has to do with the structure, the structural engineer designed it to be 8″ thick concrete outside, then a 2×4 stud framing in the middle and 6″ thick concrete inside. The builder and concrete contractors looked at this design and said “what the #$%#?” Why would the structural engineer design a studded wall inside the BFC wall, and then make it 18″ thick??? Its a single story house, when I saw builders put these walls up in my area, they have typically been 8-10″ thick with no wooden framing inside.
Any help would be greatly appreciated.
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