Advantech or CDX Plywood Exterior Wall Sheathing
Due to increasing costs, my builder and I are looking at replacing CDX plywood with Advantech. I’ve heard Advantech is a “premium” OSB, but I’ve never heard that term before. Are there other premium OSB products similar to Advantech?
I am pretty fearful of any kind of OSB product over the long term (50+ years) so I am hesitant to have any OSB.
How does Advantech compare when it comes to:
1. Airtightness vs plywood,
2. Water management (we are planning to have a rain screen and WRB product), but I am concerned about warping, mold, and OSB going bad if for some reason moisture is retained.
2. Nailing/fastener holding power over the long term.
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Make sure that the wall complies with the recommendations in Table 2 A or B here. Use the right perm value (probably ~1 perm for Advantech).
Jon,
It's too bad that advice couldn't just come up automatically when wall assembly questions are posted about here. It's an invaluable starting p0int for any design.
Hi Jon,
Looking for some advice as im not completely understanding how different materials work together in that guide. In my case we're looking to do Intello as an interior retarder (variable permeability) then 2x6 wall with. 5" cdx and then Mento 3000 wrb. Finally, covering the wrb with 1.5" of rockwool comfortboard. Brick is the veneer and house is in zone 5 (Chicago area). Would it be better to swap the sheathing to advantech? Or maybe get rid of the Intello retarder? Just thinking that drywall paper will get wet in winter time when moisture is trapped between retarder? I know that latex paint will also block vapor to a degree so maybe im just overthinking it..
I don't think Advantech is rated for wall sheathing. Zip Board is the sheathing product from the same manufacturer.
Fwiw Zip seems to dominate the sheathing market these days. Distant second is OSB with Tyvek. Zip and plywood are similar price points. OSB is cheaper but more work. I think most people willing to spend what plywood costs opt for Zip.
I would not hesitate to use Advantech instead of CDX even for a second. Advantech is an exceptional product. Interesting though that you have access to the more sheathing appropriate 1/2" and 5/8" products, it seems. I only see 3/4" and 1 1/8" Advantech stocked near me (NJ). Last time I investigated 5/8" Advantech, it was special order and actually money more than Zip.
And to be clear, I would not use a no-name OSB instead of CDX.
Thank you Patrick! It sounds like Advantech sheathing is just as good as it’s subfloor product when it comes to moisture.
How about fastener withdrawal strength?
1/2” Advantech is available, and around 20 dollars cheaper than CDX currently. Advantech is more expensive than Zip in my area, but we’ve budgeted for Prosoco WRB already, and just looking to replace CDX.
I’ve been told that Zip sheathing is a lesser quality OSB in terms of shear values than Advantech and plywood.
Sam,
I'm not sure quite how to put it, but that information is inaccurate.
Much of a shear panel's strength is derived from the fastening schedule around the perimeter, an not so much from the field. If you look at Huber's documents, you can find the shear values for for intervals of six, four, and three inches. A 7/16 OSB wall nailed at 3" has a higher shear rating than a 19/32 wall nailed at 6", etc. Here's a doc that shows how the shear values scale with decreasing intervals between fasteners, comparing zip to half inch plywood:
https://www.huberwood.com/uploads/documents/technical/documents/Shear-Capacity-Comparison-of-Plywood-and-ZIP-System-Sheathing-Tech-Tip-Wall-ZIP-System.pdf
Executive summary -
7/16 zip @ 6" spacing = 240 lb/ft
7/16 zip @ 3" spacing = 450 lb/ft
Up until internal stress causes tearing along the diagonal in most rectangular frames, it OSB's performs largely the same. The most common failure mode is bending / pullthrough of the fasteners around the perimeter though, so that rarely every happens.