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Re: Housing Performance Objectives

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It was advised on this thread to get involved with code committees, and in
six hours the SEAOC Code Committee meets in Oakland. I have just finished
reviewing the latest "first" draft of the yr. 2000 IBC Chap.23 on Wood,
consisting of 58 pages, and faxed comments to my local committee's chairman,
who is attending. He was also informed of the lively debates on the
listserve this week and urged to visit the archived postings.

Chap.23 includes Conventional Construction as Sections 2304 and 2308, and
that portion was my task to review and report on. Our Central section has
had a keen interest in Conv. Constr. for 6 or 7 years now, not as
originators of revisions, but mostly as skeptics to revisions. This role
caused these post- Loma Prieta code change proposals lots of exposure and
scrutiny. No Conv. Constr. code change was a walkover, not until the lateral
force aspects of it were reassigned to Seismology Committee a couple of
years back. But now perhaps Code has a voice in it again. Maybe. Nobody has
the same story; it's like which blind man you ask after they got to touch
the elephant. Same for the review process within and beyond SEAOC.

It appears that Conv. Constr. in the Draft 2000 IBC has lots that will
please those who want to close the presumed performance gap with "fully"
engineered wood frame projects of similar scope. In the more severe seismic
locations (no more "zones") some wall bracing has to be run up through the
attic, for example, but not all of it. Blocking and shear transfer
connections appear to be much more thoroughly covered. It is safe to say
that those who originated the draft provisions are enthusiasts for much more
comprehensive and effective seismic- resistant provisions. Nobody labors
that much without a passion for the cause.

Ah, but there's a rub: The engineered wood frame provisions elsewhere in
Chap. 23 haven't escaped upgrading either, and it's an open question whether
that performance gap has closed at all, or merely relocated upwards. We have
a code-improvement race going on, like the arms race was. As Mr Lew
knowingly asks, how much cost of this can we afford? 

And as was also hinted at, there is the spectre of SE's writing code to
feather their own nests. I believe some of that exists in this draft in the
form of rather innocuous configuration features in a house being stated, any
one of which causes the entire house to be called an "irregular structure"
and totally disqualified from use of any conventional construction
provisions. Even the rafters would have to be engineered. This is limited to
the strong seismic localities, perhaps so as to not provoke dissent among
most of the adoption-voting building officials out-of-state. 

Similarly, the draft Conv. Constr. provisions are peculiarly vague about
the permissibility of substituting in an engineered element for a
prescriptively required one. For example, where an interior braced wall line
is required to be supported on a continuous foundation, but a basement
occurs below, can an engineer design a beam to serve as the wall line's
support? It doesn't really say so.     

The SEAOC Committee meeting I attended last July heard the above misgivings
expressed and they agreed, I thought, to relief. It was understood that a
so-called irregular structure would henceforth only need engineering as
necessary to remedy the consequences of the feature that gave rise to the
"irregular" label, so that conventional construction provisions could be
used elsewhere, as otherwise applicable. The agreement to make this change
seemed a bit unwelcome, though, and 5 months later, hasn't appeared in print.

Which returns one to that "passion for the cause", where much of the
strongest SEAOC committee energy appears to spring from...both pro and con.
Being a member and advocate in an altruistic cause to save others from a
forseeable harm is intense and compelling for many, many people. This sort
of mission can turn fiercely partisan. Consider the bitterly opposed
pro-life and pro-choice factions. Each strives to rescue a victim from the
other. Each resorts to the same sort of tactics and loathes the other.
They're actually just like each other but for one thing: where they believe
the victim to be rescued is found. At opposite ends of the same umbilical

So where should SEAOC policy be resolved? SEAOC still has a board of
directors that isn't hamstrung by prideful impasse. Cannot direction come
from them?

Charles O. Greenlaw, SE.  Sacramento  CA