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RE: Redundancy factor 1.0 for single story wood framed?

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Your argument is compelling.  I believe that the unanimous agreement
among those who wrote the original 10/lw is as you have described it
(a counting tool for walls longer than 10' and not a penalty factor
for shorter walls).  However, some people have latched onto the
penalty and say, "although not intended by the original authors,
discouraging short concrete or masonry walls is a good idea."

I believe that there are some warts on the redundancy factor even as
written by the original authors.  Adding another level of unimplied
intent seems foolish to me.


- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Michael Valley, P.E., S.E.                   E-mail: mtv(--nospam--at)
Skilling Ward Magnusson Barkshire Inc.              Tel:(206)292-1200
1301 Fifth Ave, #3200,  Seattle  WA 98101-2699      Fax:        -1201

-----Original Message-----
From: Bill Allen, S.E. [mailto:Bill(--nospam--at)]
Sent: Thursday, November 09, 2000 4:42 PM
To: seaint(--nospam--at)
Subject: RE: Redundancy factor 1.0 for single story wood framed?

4/lw? Where did THAT come from? Where have I been?

According to Dick Phillips, alledgedly the author of "10/lw", it was
intended to be a penalty for short shear walls, but an "aid" to long
walls. Doesn't anyone care WHY things are in the Code anymore? The
intent of
"10/lw" was to remove the penalty on those long shear walls by
them to be a collection of shear walls with a length of 10 ft each.

Based on this, the concept that "10/lw" is NOT a penalty for short
walls should apply to more structures than merely one story wood
buildings. IMO, the code should read, wherever referencing "10/lw" to

Even though the IBC 2000 is not being adopted, don't plan check
have a copy on their shelves and/or don't they follow comments on this
and position statements presented by SEAOC? Anyone going to ask why
feature was adopted into the IBC 2000?

If not, maybe SEAOC can prepare a position paper like they have done
on a
couple of other issues. These have been very helpful considering there
no off year corrections to the 1997 UBC.


Bill Allen, S.E. (CA #2607)

-----Original Message-----
From: Lynn [mailto:lhoward(--nospam--at)]
Sent: Thursday, November 09, 2000 3:17 PM
To: seaint(--nospam--at)
Subject: Re: Redundancy factor 1.0 for single story wood framed?

Thanks, but I think Ben answered my question for me.
It was that the 10/lw was changed to 4/lw for wood

Paul Feather wrote:
> Lynn,
> The only proposal I am aware of is that 10/lw should not exceed 1.0
> shear walls, I can look up the paper later if you would like.
> I am not aware of any limitation on Rho
> Paul Feather
> ----- Original Message -----
> From: "Lynn" <lhoward(--nospam--at)>
> To: <seaint(--nospam--at)>
> Sent: Thursday, November 09, 2000 10:55 AM
> Subject: Redundancy factor 1.0 for single story wood framed?
> > I thought I had read on this list that there was an
> > official proposal or some kind of document put out by
> > SEAOC that was recommending a change in the code to
> > allow the use of Rho to be 1.0 for one story wood
> > framed structures (or was it just residential
> > structures?).
> >
> > I have reviewed the archives of the "list", and have
> > found there has been a lot of discussion on the matter,
> > but I could not find the document I was looking for.
> >
> > Is there any kind of a document circulating that is
> > proposing that Rho can be 1.0 for all one and two story
> > light wood framed structures?
> >
> > Thanks
> >
> > Lynn
> >
> >