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RE: IBC "Oops" (Was Residential Design Discussion)

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Thank you, Bill. It is comforting to know that at least one person
understands my position. I'd like to get a few things on the table about
my "supposed" trashing or spam on such well known people as Ron
Hamburger and the "fine" members of our profession who volunteer their
time to participate and create codes.

I am not addressing those in regard to the design practices of Steel,
Concrete or Masonry. I am strictly refering to the design of low-rise,
predominently residential structures that have two codes which may be
followed. One complies with the work of the SEAOC Sesismology Committee
that has become codified as the 97 UBC and is virtually unchanged in the
latest California Building Code provisions. And the second is the
prescriptive methods of wood design led by the National Association of
Home Builders who are primarily doing work for the benefit of the US
Department of Housing and Urban Development or HUD. Because SEA has
chosen not to waste their time on wood design OR have chosen to dismiss
the recommendations of the SEAOC Seismology Committees wood
sub-committee formerly led by Bill Nelson, SE of Johnson & Nielson, a
company who produces nearly or approxiately $2-billion dollar a year in
residential tract housing.

I would doubt that any member of SEA or the other supportive groups
would attack my qualifications in wood design or in seismic design. They
may question whether or not I fully understand the code cycle, but I
think the issue is not the adoption of code, but the abililty and range
of voting members needed to change a code. My "attack" is on the
arrogant people who are within our profession who choose to "dismiss"
our concern and in the process attack our livelihood. These individuals
have little if any experience in wood design yet have the gall to attach
me for criticising the organization who volunteer their time to create
something so magnanamouse as a building code or law for the protection
of the public.

Still, this does not resolve a frustrating situation that is
contradictory to the intent of the code by creating an incentive for
those who have the ability to modify or simplify their design and
comform to the provisions of prescriptive construction.

To make matters more complicated, those who criticise consider my
arguments to be seismic related and for custom high end structures,
residential hotels, apartments and multi-family structures, they are
correct. However, the majority of low-rise residential structures that
are affected by this problem are within the wind load design provisions
of Chapter 16 that still do not comform or compete with the prescriptive
versions of the code. I often wonder how many of these great men have
ever run the numbers on small 1200 to 1600 square foot one story
structures that reprsent thousands of units in Riverside county. These
homes are restricted to one story so as not to obstruct the view of the
mountains in the distance. Still, these same homes are not equal to
conventional framed homes of UBC section 2320 which do not require
tie-downs on conventional braced panels that under the provisons of UBC
Chapter 16 calculate to have an uplift unless the roof is clay tile. In
this case, the seismic provisions govern and the uplift is considerably
higher. This, of course, assumes that the tributary area of these shear
walls is one-half of the 40-foot width which is the maximum span of the
wood trusses. The use of inteiror partitions is unreasonable with these
structures as it is difficult to transfer shear where the trusses are
perpendicular to these walls and span the full 40-feet plus any eave

If you accept my qualifications in the design of wood structures and
understand that uplift occurs on smaller homes calculated with a  70-mph
wind load in exposure C then the potential for damage or poor
performance exists in almost every area of the country.

Why complain about the messenger. I understand that you don't like those
revered by the industry publically criticised, but consider my
qualifications in the design of light-framed residential design and
consider the abuse I have taken because I have chosen to be outspoken in
the industry. 

Bill is correct and I recently wrote a similar response to Charlie
Carter whose advise on Steel (as well as Scott Maxwell's participation
in concrete design) I have tremendous regard for. Although I don't work
for APA or AF&PA or AWC - I think I deserve the recognition as a
professional who understands residential design as well as seismic
design and who has paid my dues to the industry in both volunteer
participation as well as experience in the number of homes I have
designed bother large sprawling custom homes and hundreds of low income
structures in wood and CFS for families who could not afford otherwise.
My point of engineering these homes was that we live within five miles
of the San Andreas Fault on the west side and there are few that
question the potential risk to this area other than the Building
Industry Association and the National Association of Home Builders who
has stated publically that the damage to homes in Northridge represents
the unreasonable standard of expectation as to the level of performance.
As long as their home did not collapse or otherwise cause personal
injury, the homes performed within the accepted range according to the

I might point out that since the range of damage exceeded $30-billion
dollars (which the NAHB dismisses as due to the excessive overcharging
of the building industry) and this caused the insurance industry to move
out of California. The basic opinion of the public is that this is
unacceptable and having to deal with a state's Fair Plan for coverage is
hurting the pocketbooks of the residence in the state and will bankrupt
the Free Plan once another earthquake equivalent to Northridge or Loma
Prieta hit the state. This, of course, does not even consider the
potential for a once in a hundred year wind that might hit as it can in
any other state.

So, I suggest that you consider my qualifications and knowledge of wood
construction and the code as well as the problems that affect the deisgn
of residential housing when there is an alternative design process using
a less restrictive provision within the same code. What other material
in our building code has an alternative prescriptive method of design
that can be used instead of an engineered solution? When you can answer
that and design a few wood framed homes, then you may be qualified to
understand and comment on my frustration.

BTW, if anyone is interested in obtaining my letter sent in August of
1999 to Bill Nelson regarding the 7/12/1999 Blue Book, Wood Chapter
Draft comments - I would be happy to post them on the website (rather
than send them directly to you as this takes a lot of time. I think I
cover most of the issues in great detail including comments on the
Vision 2000 Objectives.

Dennis S. Wish, PE

-----Original Message-----
From: Bill Polhemus [mailto:bill(--nospam--at)] 
Sent: Monday, September 30, 2002 5:44 PM
To: seaint(--nospam--at)
Subject: RE: IBC "Oops" (Was Residential Design Discussion)

> -----Original Message-----
> From: Sprague, Harold O. [mailto:SpragueHO(--nospam--at)]
> Sent: Monday, September 30, 2002 2:35 PM
> To: 'seaint(--nospam--at)'
> Subject: RE: IBC "Oops" (Was Residential Design Discussion)
> Charlie's take on this is accurate.  There were impediments to seismic

> code development in the old process.  Ron Hamburger and Bob Bachman 
> were instrumental in moving seismic code development into the FEMA
> sponsored BSSC
> process.

I can't speak with any authority as to this, since I and my 12 year old
daughter both have about equal experience in the seismic engineering
code development process, but I have an observation.

It sounds as though those who are making these statements, including
Harold, Charlie and others, are actually talking around the point that
Dennis is trying to make.

I don't think Dennis has said that the entire code development process
is "corrupted," or that there is NO good work coming out of the various
committees who have input into that process.

If I read him correctly, I believe he is limiting his criticism strictly
to the provisions in the UBC 97 that seriously handicap light-frame wood
structural design, forcing design of uneconomical structures to a degree
that, if similarly handicapping provisions were insisted upon in
structural steel design, say, there would be a tremendous outcry from
those who design those structures as well. But because the light-frame
wood design market is not the "mainstream" of structural engineering
design, the loophole remains open and any attempts to close it are met
with a stone wall.

If my observation is not accurate, please forgive me, but I have taken
pains to try to follow Dennis' rants over the past week. He is incensed
that, in order to design wood frame structures--especially
shearwalls--reasonably and economically, the designer has in essence to
break the law, or face losing work to those who ARE willing to break the

For someone like Dennis whose practice is firmly grounded in wood
residential and light-frame commercial work, that is an impossible
position to be in. But because those involved in seismic code
development have other areas of interest at heart, it's not being

I hope I've got that right, and I hope that we can all see through
Dennis' fit of pique to the underlying cause.

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