Anchor Spacing for Wood Stud Walls subject to Lateral/Uplift Loading
Anchor Spacing for Wood Stud Walls subject to Lateral/Uplift Loading
(OP)
I was reviewing section 4.4 of the AF&PA SDPWS-2008 - Special Design Provisions for Wind and Seismic standard, which covers wood structural panels designed to resist combined shear and uplift from wind. In section 4.4.1.6. it states that bottom plate "anchors shall be spaced at 16" on center or less". I don't see this tight spacing requirement anywhere else in the code.
Why would this only apply when you are using wood structural panels to transmit uplift? What if you are sending the uplift in a shear wall directly through the studs through toenails or hurricane ties? How is that any different for the combined shear and uplift on the anchors?
BTW, the document can be viewed here.
http://www.awc.org/standards/sdpws.html
Why would this only apply when you are using wood structural panels to transmit uplift? What if you are sending the uplift in a shear wall directly through the studs through toenails or hurricane ties? How is that any different for the combined shear and uplift on the anchors?
BTW, the document can be viewed here.
http://www.awc.org/standards/sdpws.html






RE: Anchor Spacing for Wood Stud Walls subject to Lateral/Uplift Loading
Garth Dreger PE - AZ Phoenix area
As EOR's we should take the responsibility to design our structures to support the components we allow in our design per that industry standards.
RE: Anchor Spacing for Wood Stud Walls subject to Lateral/Uplift Loading
Mike McCann
MMC Engineering
RE: Anchor Spacing for Wood Stud Walls subject to Lateral/Uplift Loading
But shouldn't then that requirement also apply if you are using hurricane ties on each stud to transfer uplift? I don't see where that is much different as far as how the bottom plate transfers combined shear and uplift to the anchors.
Is this common in some parts of the country? I practice in the Gulf South and I have never seen that. In fact, I'm not sure if solid 3x and 4x members are readily available. We usually "gang" 2x members to make bigger beam and column sections.
RE: Anchor Spacing for Wood Stud Walls subject to Lateral/Uplift Loading
Mike McCann
MMC Engineering
RE: Anchor Spacing for Wood Stud Walls subject to Lateral/Uplift Loading
Jason A. Partain, P.E.
www.myconstructionfinds.blogspot.com
RE: Anchor Spacing for Wood Stud Walls subject to Lateral/Uplift Loading
And how do people usually account for the twisting action on that plate since the hurricane ties frame into the side of the plate and the anchors are usually centered on the plate?
I find it odd that they do it for for this application and not others.
RE: Anchor Spacing for Wood Stud Walls subject to Lateral/Uplift Loading
If this is of concern, then alternate the hurricane ties to either side of the plate.
Mike McCann
MMC Engineering
RE: Anchor Spacing for Wood Stud Walls subject to Lateral/Uplift Loading
Jason A. Partain, P.E.
www.myconstructionfinds.blogspot.com
RE: Anchor Spacing for Wood Stud Walls subject to Lateral/Uplift Loading
RE: Anchor Spacing for Wood Stud Walls subject to Lateral/Uplift Loading
No.
I'm just concerned with the requirement.
Really, I am curious about the twisting action on the plate due to sheathing or hurricane ties being attached to the side of the plate and how most engineers have been handling it? When using hurricane ties, do most stagger the side of attachment to prevent the twisting action?