Attorneys will tear you up in court if you designed "for only the minimum",
especially when common practice was to use plywood shear walls which are well
above the minimum.
Stan Scholl, P.E.
Laguna Beach, CA
The client is not as
interested in residual strength as I am. He is interested in meeting code.
From that perspective, how do you think he would respond to the suggestion
that the building be designed for a lower R value and lower SW capacity than
the current building code prescribes as well as story and roofing system
limitations not specified in the building code? Don’t get me wrong, I agree
with all of your points that the structure you describe would perform much
better. But if my customer is looking to meet building code minimums, I need
more data that this (like LARUCP has banned such materials).
BTW, the project is
in the city of Riverside.
T. William (Bill)
(949) 248-8588 •
Sent: Friday, June 23, 2006 12:03
Subject: Re: Stucco or GWB as shear wall
in seismic zone 4 (1997 UBC/2001 CBC)
try and convince him that plywood/OSB provides a lot more residual strength to
resist seismic forces, especially racking action in a house..its just to
brittle. Like Charley said, I am concerned about using GWB because of
its lack of post peak strengthen beyond peak
was to design with GWB it would have to be limited to a single story house (no
tile roof), lots of walls so the seismic forces in the walls were less than 30
pounds/ft ..not the higher values shown in the UBC (also shear wall lengths no
less than 8 feet long) and I would probably look at using an R value much less
than 4.5 (97 UBC), probably closer to 2.0 (I believe R = 2.0 in the current
IBC). At this point, I don't think GWB would work for the design loads
unless you had a lot of long walls.
LA City limits GWB to 30 pounds a foot.
message dated 6/22/2006 6:17:59 P.M. Pacific Standard Time, T.W.Allen(--nospam--at)cox.net
haven't used stucco or GWB since Northridge, but a new customer is
me to look into it. If the loads are less than the capacity (even
reduced capacity of GWB), I might have trouble justifying WSP just
it "feels good".
Does anyone have evidence which
would allow me to not use stucco or GWB as
SWs and still feel like I've
tried to accommodate a customer's