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Re: Wood: Conventional Framing opinions needed from other states

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In a message dated 97-11-30 13:50:17 EST, Dennis Wish write:

> If you feel that residential construction (wood framing) is best left to
architects
>and non-engineers please let me know why you feel this way.

Dennis has framed the question in a "go-no-go" manner that considers only two
scenerios:  Engineers either would stop doing residential design ("best left
to" (non-engineers)), or exempt buildings would be done away with and
engineers given a monoply on all strucutral design.   Neither is realistic -
many engineers wouldn't agree to the first, and the second would be bad public
policy and has no chance to make it into law.  But a third option is to
continue the current situation, which I believe is adequate, as discussed
below.

> If you feel that prescriptive methods in the UBC or comparable codes do not 
> adequatly provide for the mitigation of damage, let me know why.

Of course, wood-frame residential buildings have been, and will continue to
be, damaged when subjected to significant ground shaking.  This isn't
surprising or unexpected, even for engineered buildings (recall the Blue
Book's stated objective that buildings designed to its provisions may
experience major damage in a MCE).   But whether the codes "adequately"
mitigate the damage involves consideration of more than just the economic
losses to the affected homeowners.  The larger public policy issue is whether
those code provisions are cost effective for society as a whole  [Note:  Life
safety is not at issue - deaths and injuries due to lateral load path failures
in exempt residential buildings are almost non-existent].

To develop my point, let's look at a situation in another discipline.  Readers
of this listserv likely are aware of the "Year 2000" (Y2K) problem in the
computer programming and data processing fields.  There are estimates that it
will cost more than a billion dollars to fix the problem just in the U.S.
Pundits and critics have tsk-tsked about how shortsighted, penny-wise and
pound-foolish the folks in information technology have been.  Why, just by
allocating two more bytes to the date fields starting back in the '50s, the
Y2K problem would never have arisen!  Now, here's the rest of the story as
told in a PC Week article some months ago: those avoided bytes helped data
processing managers avoid or delay lots of capital expenditures to upgrade to
more powerful machines, add core memory, disk drive/tape storage units, etc,
which were more expensive in earlier decades.  When they finally made
upgrades, they got more bang for the buck from rapidly improving hardware.
It's estimated that the missing bytes allowed the DP folks to get by with one
less generation of hardware purchases.  Additionally, the time for backups and
other data transfers were shorter, thus reducing labor costs in operations.
These avoided costs at all the mainframe installations used in government and
business positively affected the taxes and the prices of goods and services
that we paid.  Collectively, they added up to sums that, when combined with
any reasonable assumptions on return on investment for the avoided
expendirures over the years, are several times the cost for fixing Y2K.  The
main reason the bill is a shock now is that it is more prominently highlighted
and must be paid over a more compressed time period.  But it isn't a
boondoggle, and society came out ahead.  

Now lets apply this example to seismic/structural design of houses.  I assert
that the avoided costs of conservative seismic design for houses can offset
many times over the costs of  "Y2K-level" expenditures for repairs after a
damaging event.  I'll use round numbers to make the math easy, but the
magnitudes should be valid.  Assume that, due to engineering fees and extra
labor and materials above and beyond what contractors would do under
prescriptive requirements, engineered houses cost an average of $1,000 more
than non-engineered ones.  Some 1.2 million new housing units are built
annually in this country.  Assume that half of them are engineered because
they are apartments, custom homes or mobile homes.  That leaves 600K units
that will incur the added costs if Dennis would have his way - $600 million
*annually*, or about $13 billion in the interval between the San Fernando and
Northridge events.  And that's not including ROI results.  Yet, the vast
majority of the 13 million non-engineered housing units built during that
interval won't experience strong ground shaking during their service life..
To impose a 100% solution on a 5% problem is a questionable use of society's
resources, and questionable public policy.   And it may not even be 5% - it's
unlikely that all the damaging earthquakes in the U.S. in this century,
collectively, damaged as much as 5% of the country's housing stock (or even
California's).

>If you have specific knowledge of ICBO's position justifying this section of
the
>code, I would like this to be explained as well.

I've no specific knowledge, but having served five years on its Lateral Forces
code development committee, here's my take on the situation.  The cost of
compliance with a regulation is a tax on the public, albeit a less transparent
one than other taxes.  Before taxes are increased, there has to be public
debate, and finally taxpayer acceptance.  That sentiment has become
increasingly strong at all levels of government.  Legislation that would in
effect give engineers tax collector status on residential buildings, even if
well-intentioned, would have no chance in today's political climate.  Given
this climate and the environment that building officials operate in, it's very
unlikely they would approve a non-safety-based code change from a special
interest group that would create a monopoly and constitute taxation without
representation.  That's understandable, and proper.

Frank (where are the bodies?) Lew, SE
Orinda, CA
f(--nospam--at)lew.net