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Re: Wood: Conventional Framing opinions needed from otherstates -Reply

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I have been off the past few days repairing my computer and would like to
make some comments for Frank Lew's responses.

First, I don't feel that I am on a personal crusade to eliminate the
conventional framing section of the code. I am, however, on a crusade (if
you wish to call it one) to insure that the provisions behind this section
of the code are no less stringent that any other chapter of the code. I base
my opinions on the following facts.
1. Engineers generally do not design by the prescriptive measures in UBC
2326 - Conventional Framing.
2. The section of the code is to be used in lieu (sorry Frank) of a
professional engineer or architect.
3. There are known discontinuities in section 2326 that are either mistakes
or deliberatly left out of the code. These include the proper connection of
interior braced panels to the roof (no mention of how to do this or what is
required) in section 2326.11.4. What purpose does a braced panel serve if
the load path is not developed?
4. The intention of the code is to provide a prescriptive measure for a
non-professional. I challange anyone to find a framer that has read this
section of the code and understands the provisions.
5. In smaller towns building inspectors interpret this section of the code
and are open to virtually any agument as to the validity or meaning of the


section. As an example, the local building official did not require the
contractor who built a home under the provisions of this section to connect
the braced panel inside a home to the roof. Inasmuch as the code did not
specifically state that a connection was required, the building official
could not enforce it. The wall was left attached at the ceiling
(perpendicular to the bottom chord of the trusses). With almost 50% of the
lateral force developed in the interior panel, the load would certainly
exceed the capacity at each end - one of which was a 2'-8" wide x 10' high
braced panel at each side of the garage constructed in accordance with
section 2326.11.4.
6. Contractors are not required or tested on sections of the code such as
this. They are only required to follow what is written on the drawings that
they build from.
7. Most cities do not simplify the conventional framing section as Los
Angeles did with their graphical Type V sheet.
8. The Insurance industry has suffered a considerable loss due to damages
caused by failures such as those associated with excessive story drift,
improper nailing or damage to panels, improper construction techniques and
inadequate design methodology. Rather than learn from these problems, the
Conventional Framing section of the code is expanded into a more complex,
broader range document that will expound the potential damage, rather than
attempt to mitigate it.
9. More homes damaged in wind and seismic related events remain damaged or
are patched rather than fixed with the intention of reducing or eliminating
preventable inadequacies (ie, cripple wall repair is a voluntary measure
that is mandated only by a disclosure to future buyers).

Life safety is not the issue here. Tim McCormick may have pointed out those
failures attributed to wind or seismic that caused a loss of life (there was
one life lost in a collapsed chiminy during Northridge that I remember -
also a wood framed home). However, my crusade is the mitigation or reduction
of avoidable damage - certainly a reason so many insurance carriers left
California and we now have a state plan. Look at the proposals for cripple
wall repair and foundation anchorage. A homeowner who invests in this type
of repair will gain much more than simply increasing his insurance coverage.
Many engineers advocate taking the premium payments for earthquake coverage
and investing it into a retrofit - which has proven positive effects.
Frank, how can you expect a non-technical, non-professional layperson to
follow a technically written code? At least the city of Los Angeles,
publishes a graphical Type V sheet that contractors use to help
non-professionals construct wood framed buildings. This I would support as
long as the engineering community established the minimum standards for
construction. The 1994 Conventional framing section expanded from the 1991
code to include irregular shapes and multi-stories. The 1997 code (although
I have not reviewed any more than drafts) promises even more rhetoric and
confusing standards.

I reviewed many documents sent to me recently by Charles Greenslaw SE
regarding the Conventional Framing issue. In an effort to keep this section
of the code simple, Central Chapter of SEA took a stand against the revised
expanded 1997 code. They were criticised by the other chapters for the
reason that SEAOC abstained from voting on the section at the ICBO meeting a
few years ago. How absurd! Rather than debating and resolving the issues in
conventional framing, SEAOC blames one chapter for not supporting the other
three and therefore allowing a "bad" code to become law.

This is getting into a can of worms that I don't have time to address here,
but this is the reasons that I asked for opinions. Section 2326 is not
written nor supported by the entire engineering community and, in fact,
appears not to have been voted on at the ICBO convention by SEAOC. We
therefore have no professional stand to take. However, those of us that have
to fight clients who demand that those structures which are required to be
designed by engineer (non-compliant structures) be designed by minimum code
standards - even those standards not supported by the professional
community.

Why, then, should we defend a poorly written and mostly ignored code when an
easier presriptive method is warranted? Why should any one section of the
code be written to provide less protection of the public than another
section? Why must our profession accept the publication of a section of code
that is not consistant with the opinions of the majority of the structural
engineering community? And finally, why must the structural engineering
community be out-voted by non-engineers when it relates to engineering
issues?

The next time we inspect damage, be thankful that the homeowner did not lose
his life, but don't forget to wonder where he and his family are to be
displaced to for the unforeseeable future awaiting the repair of thier home
or accepting the loss of their property without the financial resources to
cover their deductable.

Sorry, but I'm back to my verbose self. I guess it boils down to feeling
that an adequate design does not need to cost more money, it only needs to
be communicated properly and enforced in the field.

Respectfully
Dennis S. Wish PE