Wall assembly choice
Hey all. Need some advice on wall assembly. I’m in Climate Zone 4 – KY and building a stone/brick veneer on wood frame in Spring. Important to me that wall assembly protect against water, air, vapor, thermal but I’m sensitive to VOCs and off gassing too. So, my idea is: 2×6 traditional stud frame 16 OC with ZipR-9 (5/8s brown) taped or 2.0 liquid seams (?), with rainscreen furring, Stone/brick cladding. In stud cavities – Owens Corning Thermafiber (formaldehyde free) wool bats, with Sheetrock.
Subfloor- Advantec 1 and 1/8” DAP glued and nailed.
I originally wanted to go with 3/4” plywood sheathing with Delta SA peel and stick wrap, but my builder is pushing ZipR instead to save a trip around the enclosure I assume. Being old school, I’m worried that 3/4” plywood is better than the 5/8” Zip OSB? Or I thought maybe Advantec Sheathing 23/32” with Delta SA wrap bc heard its super strong and water resistant. Confusing myself now. Lol
Thoughts or advice on these from you all who have worked with both? Thanks!!
Mike in KY
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Replies
Hi Mike.
Unless I am missing something, your options aren't apples to apples, meaning that your not just swapping one approach to sheathing and WRB for another. The ZIP-R adds continuous R-value to the wall, the plywood and Delta SA doesn't. If you chose the latter, would you add a layer of exterior continuous insulation? Otherwise, you are sacrificing considerable R-value and the potential to slow thermal bridging.
You'll get different opinions on OSB vs. plywood sheathing. And some builders think ZIP is the best thing going, others think it is garbage (mostly people who think OSB in general is garbage). As part of deciding on products, I think what your builder is comfortable with should carry some weight.
Brian. Yeah, I left out I’d probably use rockwool Comfort board with the plywood option. But in general I’m reluctant to put an insulation between the Brick cladding (Rainscreened) and the studs - I know Huber says tight nail pattern will secure it - just uneasy, I guess. Being in Climate zone 4, wouldn’t Advantec Sheathingwith Delta SA and Thermafiber batts do a pretty good job without the worry of nailing thru the exterior insulation?
Yes, Mike. That would work.
I've been seeing more and more Advantec on walls lately. I'm not sure if it is belt and suspenders thinking or what. I would feel comfortable with plywood and Delta SA and really good flashing details.