Sill Plate Requirements for shear walls exceeding 350 PLF
Sill Plate Requirements for shear walls exceeding 350 PLF
(OP)
I'm trying to find the provision that allows a 2x sill plate for walls less than 600 plf if the anchor bolt capacity is reduced (the exception to the 3x sill plate rule). It was in the 2010 CBC (IBC), but with the new 2013 version, not only can I not find the provision, I can't even find the wood structural panel table for nailed walls (it only has the one utilizing staples). I have found the table utilizing nails in the AFPA, but that one has no provision for the 3x sill plate rule at all. If anyone could point me in the right direction I'd really appreciate it.






RE: Sill Plate Requirements for shear walls exceeding 350 PLF
Nearly all of the seismic design for wood shearwalls and diaphragms has been removed from the main body of the code and instead refers to NDS SDPWS.
RE: Sill Plate Requirements for shear walls exceeding 350 PLF
You'd think they'd at least leave the tables and requirements in the same book when they update these things. By the time we get used to where everything is, they just change it all again lol.
RE: Sill Plate Requirements for shear walls exceeding 350 PLF
But with a plan reviewer you always have to decide if its worth the fight.
The body of the code is trying to remove all actually information and instead use reference documents instead. In theory I think it is good but in practice it is a headache.
RE: Sill Plate Requirements for shear walls exceeding 350 PLF
1. Using 3X vertical studs at the panel joints gives 1.25" each side for nailing. A 2X plate gives 2.5", greater than the panel joints.
2. The use of washers of specific size and thickness at the sill plate anchor bolts allows a 2X to be used instead of ta 3X.
3. As I recall, the 3X requirement originally did not specifically mention sill plates, only "all boundary members", which would include the top and bottom plates.
So, two questions ensue:
1. Was the requirement poorly written, allowing for misinterpretation, and it was subsequently corrected, or
2. Was the data from the Northridge event over-reacted to (CYA), misinterpreted, or is this a change based solely on economics and contractor/developer complaints...again?
Comments?
Mike McCann, PE, SE (WA)
RE: Sill Plate Requirements for shear walls exceeding 350 PLF