Deflection of stud walls at ends (where wind pressure is higher)
Deflection of stud walls at ends (where wind pressure is higher)
(OP)
At my firm we calculate the out of plane deflection for stud walls. The deflection is limited so that the stucco will not crack. Because of the increased wind pressure at the ends of walls, when we get above 9' tall walls we almost always use 12" spacing or tighter for the first 5' of the wall to limit deflection. (The interior studs are typically 16" spacing.)
I understand why the wind pressure at the end of a wall is higher than at the interior. However, it seems that when we are calculating the deflection in a stud, the studs near the end of the wall should benefit from the return wall at the corner. I think that even though the wind pressure is higher at the end, the defection of the stud a mid-height will decrease as the studs get closer to the corner.
Do we need to worry about the stud spacing at the ends of walls?
We are based in Utah and the majority of our work is for homes in Utah and Salt Lake Counties.
I understand why the wind pressure at the end of a wall is higher than at the interior. However, it seems that when we are calculating the deflection in a stud, the studs near the end of the wall should benefit from the return wall at the corner. I think that even though the wind pressure is higher at the end, the defection of the stud a mid-height will decrease as the studs get closer to the corner.
Do we need to worry about the stud spacing at the ends of walls?
We are based in Utah and the majority of our work is for homes in Utah and Salt Lake Counties.






RE: Deflection of stud walls at ends (where wind pressure is higher)
Mike McCann
MMC Engineering
RE: Deflection of stud walls at ends (where wind pressure is higher)
Remember to take your .7 reduction factor on C&C pressures for the purposes of deflection calculations (if you are using the IBC).
RE: Deflection of stud walls at ends (where wind pressure is higher)
RE: Deflection of stud walls at ends (where wind pressure is higher)
But I think your increased stiffness at corners thinking may be from CMU and tilt panels, where I know many engineers use returns in the walls to help brace the edge zones in those types of assemblies.
RE: Deflection of stud walls at ends (where wind pressure is higher)
structSU10 do you have a section or page for your reference to L/3 in the ASCE 7 commentary?
RE: Deflection of stud walls at ends (where wind pressure is higher)
RE: Deflection of stud walls at ends (where wind pressure is higher)
RE: Deflection of stud walls at ends (where wind pressure is higher)
RE: Deflection of stud walls at ends (where wind pressure is higher)
i.e. 0.7 / 1.6 ~ 0.42.
RE: Deflection of stud walls at ends (where wind pressure is higher)
RE: Deflection of stud walls at ends (where wind pressure is higher)
Really I was just hoping we could benefit from the return walls.
Thanks for your thoughts
-Alex
RE: Deflection of stud walls at ends (where wind pressure is higher)
Just a thought.