Re: Deflection of Wood Studs for Brick

We've been involved in the deflection of stucco walls for out-of-plane wind loads lately and have come across some interesting comments concerning the deflection limitations of brick, basically for steel stud walls, but this should apply to wood as well, as the criteria to prevent the brick from cracking, no matter what the stud material is.
 
Google these two articles:

"Technical Dimensions   -  Testing Brick Veneer/Steel" - this report concerns the adequacy of the L/360 deflection limitations.

"Technical Series - 98-111 - Strength and Stiffness Characteristics of Steel Stud Backup Walls Designed to Support Brick Veneer"

http:www.cmhc-schl.gc.ca/Research/High Rise

This report suggest deflection criteria's in the range of L/1800 and L/900.

If you are designing wood studs, you certainly want to check the OOP's forces and make sure that what you finally specify actually gets included in the project.  You also want to check sill crushing.   You might review ICBO report 3607.  Although this report is for stucco systems, the structural criteria required in Section IV is a surprise for many local structural designers.

Neil Moore, SE, SECB
neil moore and associates
consulting structural engineers
shingle springs, california

distressed structures investigations

At 08:41 AM 8/6/2007, you wrote:

Trying to determine the deflection requirements for wood studs backing brick
veneer.  I know the BIA tech reports recommend L/600 for steel studs backing
brick veneer but the tech note for wood studs is silent.  Also, ACI 530
prescribes requirements for horizontal members supporting brick to be l/600
or 0.3 inch but nothing on this subject.  Based on the IBC 2006 I can use
l/240 for brittle finishes which seems a bit loose. Am I missing something
here?