Plywood sheathing thickness
user-1137156
| Posted in Building Code Questions on
For a single floor residence Is nominal 3/8 plywood acceptable sheathing on 10 foot tall walls built with 24″ OC advanced framing?
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You need to check out 2009 IRC, Section R602 (and maybe R301). There are several factors that you need to consider, like building width and height, stud size, fasteners, bracing, cladding attachment, seismic zone, shear wall or not, proximity to openings, and wind speed among others. Most cases you'll need 7/16 minimum.
You can also go to APAWood dot org, register and download all kinds of information on sheathing panels. It's free.
Jerry: I think the bigger question is "Why are you gambling the house on a few dollars?" In the grand scheme of things, the difference in price between 3/8" and 1/2", even 5/8" if required, is trivial, is it not ? There is a builder on a diy forum that uses nothing but 3/4". Go cheap on your faucets and things till you can afford better ones, IMO. Structure is critical, and doing it over is extremely expensive.
I certainly think I'll have adequate structure! The unstated details include that the wall with the 3/8 plywood is part of a double stud wall and sits 3 1/2": from another wall sheathed with 7/16 OSB on one side and drywall on the other. The two stud assembly s are tied together at the top by 7/16 OSB above both wall's top plates, spanning the 3 1/2" gap and both top plates. Additional shear capacity is given by the steel panels used to facilitate installation of 'thin brick. The difference in price between 1/2" & 3/8" pays for 1/2 of the added OSB. To me an important part of "building green" is not wasting material. If 3/8" is adequate using thicker is definitely waste.
After reading the 2009 IRC section 602 I doubt that with 24" OC framing I can use any less than 7/16" unless I can get a registered engineers stamp of approval. The approval will cost more than the savings.