Sds = 0.76, less than the 0.83 for the D2 in the IRC, but I am hoping that our design should be ok anyway, I’ll check the R602 sections.
Jason
WCA Structural Engineering, Inc.
From: Ehrlich, Gary [mailto:gehrlich@nahb.com]
Sent: Friday, December 19, 2008 11:28 AM
To: seaint@seaint.org
Subject: RE: IBC v IRC
Jason,
What is your Sds?
I’m not sure if there is a whole lot of difference. IRC SDC D2 is just a subset of IBC SDC D. I think most of the seismic detailing requirements in the IRC apply to all three sub-divisions of SDC D (D0, D1, & D2). And at this point I think the NEHRP provisions have been pretty extensively implemented throughout the IRC, so an IBC D and an IRC D2 should essentially be the same design. There may be a few wall bracing provisions specific to D2 in R602.10 and R602.11, though I would think they shouldn’t apply if you engineered the shear walls.
Gary
Gary J. Ehrlich, PE
Program Manager, Structural Codes & Standards
National Association of Home Builders (NAHB)
1201 15th Street, NW, Washington, DC 20005
ph: 202-266-8545 or 800-368-5242 x8545
fax: 202-266-8369
gehrlich@nahb.com
Attend the 2009 International Builders' Show
January 20-23, 2009, Las Vegas, NV
www.BuildersShow.com
From: Jason Christensen [mailto:jason@wcaeng.com]
Sent: Friday, December 19, 2008 12:20 PM
To: seaint@seaint.org
Subject: IBC v IRC
Does anyone know the differences between the IRC SDC D2 and the IBC SDC D. We have design a small subdivision using the IBC SDC D, but the building official wants it per IRC SDC D2. I am just if they would be equal or similar.
Jason