Cold Formed Steel Shear Wall with Steel Sheathing 1

[Rsd789]

I have a project with a new client for a storage building that's constructed out of load bearing cold formed steel framing. The client is saying in the past they've seen the lateral system comprised of 29ga sheathing and the studs being spaced at 30" O.C.

Based on the AISI S240 I'm seeing that the maximum spacing of the studs needs to be 24" O.C. and the smallest allowable sheathing is 26ga. I've called a few companies who manufacture 29ga sheathing and no one has a sheathing capacity. Does anyone know of any code provisions that would allow us to justify the clients expectations?

Thanks,

 

[XR250]

I can't imagine using thinner than 26ga for this.

 

[WIstructural]

29ga U or R panel is used for the shear walls in self storage frequently. McElroy Metals has an approval report IAPMO Report - ER-0270 that has diaphragm values in it.

 

[XR250]

Crazy how much capacity they are giving these. Looks like they require 16ga studs though. I wonder if that is ever followed?

 

[Rsd789]

Thank you this was very helpful. Not only did it answer the 29ga component but based on the document it appears AISI has 2 separate codes for shear wall designs. AISI S240 is for a standard shear wall but AISI S310 has provisions for "Wall Diaphragms" which are considered shear walls and has a set of completely different requirements. Since these are all capacities based on calculations rather than testing it can allow for studs to be spaced further and the use of thinner deck than what S240 requires.

Doesn't make sense to me as to why they would have 2 differing codes for the design of the same element but at least it's allowed by the code.

 

[Richard_Honne]

Off the top of my head, AISI S310 is for fluted metal panels. I think there is a min/max panel depth to determine strength and stiffness in section D(?)

 

[EngDM]

Thank you this was very helpful. Not only did it answer the 29ga component but based on the document it appears AISI has 2 separate codes for shear wall designs. AISI S240 is for a standard shear wall but AISI S310 has provisions for "Wall Diaphragms" which are considered shear walls and has a set of completely different requirements. Since these are all capacities based on calculations rather than testing it can allow for studs to be spaced further and the use of thinner deck than what S240 requires.

Doesn't make sense to me as to why they would have 2 differing codes for the design of the same element but at least it's allowed by the code.

You'll find this happens a lot with the cold formed codes.