Need a book? Engineering books recommendations...

Return to index: [Subject] [Thread] [Date] [Author]

RE: R values for vertical combinations exceptions

[Subject Prev][Subject Next][Thread Prev][Thread Next]
Regarding the row house, they definetly do not meet the separation requirements, I was more concerned if by definition, the buildings are considered detatched, therefore you can use the R value exception. So in order for a building to be considered "detached" does it have to meet the separation requirements? Or is a detached building one with separate foundations and structural systems with common roofing and flashing.
In San Francisco existing buildings that are seismically upgraded do not need to meet the separation requirements, I have not found that language in the California Building Code.

From: David Topete [mailto:d.topete73(--nospam--at)]
Sent: Thursday, October 02, 2008 9:20 AM
To: seaint(--nospam--at)
Subject: Re: R values for vertical combinations exceptions

IIRC, the SEAOC Blue Book had commentary/language that a designer can reasonably argue the moment frame design force based on a lower R while the balance of the structure is designed for the higher R value for shetthed wood walls.  Most building departments have accepted this argument before.

As for the rowhouse, if 3 stories tall, I don't think a moment frame or wood shearwall building would meet the building separation requirements at 1".  Good luck.

On Thu, Oct 2, 2008 at 8:59 AM, Jeff Smith <jeffsmith7(--nospam--at)> wrote:
I am looking at the exceptions to section page 122 ASCE 7-05 Exception 3
Does exception 3 mean that for a typical wood framed three story single family dwelling with a moment frame at only the garage, the building be designed for an R of 6.5 and design just the moment frame for 3.5?
Is a zero set back row house considered a "detached" dwelling, (1" between buildings)?

David Topete, SE