Why not skip the sheathing?
I am just a layperson who wants to build a pretty good home and have been considering two wall types, but as I’m reading, I feel like I’m missing something regarding the sheathing.
Many propose using exterior insulation to keep sheathing warm, but then some suggest that with diagonal wall bracing one doesn’t need any sheathing other than the foam (assuming either careful taping and/or membrane WRB and some other sort of air barrier). If so, what is the purpose of putting the insulation on the outside of the wall? I’m in central MN, so climate zone 6. If I go the rout of external insulation, I’d need about 5 inches (I want to use mineral wool to minimize foam) on the outside of a 2×6 wall which seems kind of tricky as far as screwing and siding alignment goes.
If I go with a double wall, the same basic question arises—if I use let-in bracing and membrane barriers to forgo rigid sheathing, isn’t that basically the same wall as above with just added framing to support the siding? This wall seems to make a lot of sense to me — http://foursevenfive.com/double-stud-wall-optimized-for-cost-efficiency-performance/
I continue to read about those who want to use fiberboard, densglass etc… and wonder if I’m missing another point of the sheathing.
Thanks for any reply.
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