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RE: Gross overturning

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Check into ICC Code Clarifications for the 2000 IBC (on ICC website).  I believe that there is a clarification that the safety factor of 1.5 for retaining walls does not apply to load combinations that include seismic.  Although it applies to retaining walls, it provides evidence that a 1.5 safety factor with seismic is too conservative.
Bill Sherman

From: Matthew [mailto:sandman21(--nospam--at)]
Sent: Thursday, January 31, 2008 11:30 AM
To: seaint(--nospam--at)
Subject: Re: Gross overturning

It is not the policy; the plan checker is insisting that it is common practice to use a 1.5 F.O.S.  Every design professional, including himself, he was talked to uses 1.5 when using loads at ASD level.  The shear walls range from 1.15-1.2, it would be extremely costly to get a 1.5 F.O.S.  Can anyone offer advice on convincing him that he is wrong? :)

On Jan 31, 2008 10:16 AM, Steve Gordin <sgordin(--nospam--at)> wrote:
There is none.  For seismic, everything about 1.0 is OK.  I usually use not less than 1.2.
It may be a city policy, then you are out of luck.
V. Steve Gordin, SE
Irvine CA
----- Original Message -----
From: Matthew
Sent: Thursday, January 31, 2008 10:08
Subject: Gross overturning

I have a plan check comment stating that a 1.5 F.O.S. is required for gross overturning on any building shear wall from seismic loads at ASD level.  The project is under the 97 UBC; I have been unable to find any code section that requires a 1.5 F.O.S, the only requirement is for earth retaining walls.  Could anyone please comment on where I can find the section?  Or how they have resolved a similar situation?
Thank you