Final wall stack-up?
I think I have decided on the final stack up for my walls here in Zone 5. From outside to inside: Hardi siding, firring strips every 12″, 2″ of XPS foam with taped seams, house wrap, 7/16 OSB with taped seams, 5 1/2″ open cell foam (Aloha Foam) to edge of 2×6 (24″ OC) stud interior, sheetrock with latex paint. Of course we are using an ERV in the house, Tripane Marvin Integrity Ultex windows.
I studied in depth ideas to use ZipR, Mooney straps, etc. but found none as appealing as the use of exterior foam to reduce bridging, and open cell foam to add sealing and R value.
As an aside, I am using treated plywood for the bottom two feet all the way around. And am using tape to cover the intersection of the mudsill and wall, followed by ‘made in the field’ aluminum Z flashing to cover the bottom of the foam to protect from critters and varmints. The mudsills/plates will be spray foamed as well.
Any issues with this set up? Appreciate your thoughts.
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