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RE: Single Family Housing Design

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Thor,
There are many of us out there who feel strongly about this issue.
Unfortunately, there are many policy makers in organizations such as SEAOC
who believe (from the old school) that residential design is not real
engineering. They belive that residential design is low risk stuff and
should not be considered in the code, outside of providing a minimum
standard which should be followed in construction.

Search out a post from Ron Hamburger who (I paraphrase) proudly proclaimed
the consideration to safety derived from the changes made in the 1994 UBC
section on conventional framing. He was pleased to be a part of this
creation. Then go to the building official (any plan checker in the city of
La Quinta for example) who is shaking their heads as they must approve a
project done by conventional framing standards which they know is does not
provide the minimum level of acceptablity they would require in their
jursidiction.

Why then can't the building official level his clout and demand a
professional package. For one thing, consider a major developer of single
family homes in your community who goes before the city council and
threatens to remove his project from your town unless the building official
allows compliance to the code minimum design standard. Then consider the
building official as he stands before the city council (who must approve his
future reinstatment) explaining just why he won't accept a code recognized
practice. One side offers hundreds of thousands of dollars in revenue for
the city (school fees, property taxes, assessments for roads and sewers),
the other side represents engineering ethics that considers the potential
level and the monetary effect it will have upon the homeowner. Who do you
think will win out in this game of politics? I did hear of one Building
Official in Northern California who had the guts to take on all who opposed
him. My hats off to him, buthe is an exception rather than the rule.

Next consider the "good-ol-boy" attitude of engineers who, although are
policy makers, never perform or design residential wood structures. How can
they possibly know of the abuse found in the field without first running the
numbers and comparing the results between a UBC standard and an engineered
product. One of our group asked "Isn't a minimum code standared established
in the UBC suppose to be more stringent than an engineered solution?" Good
question.

I have been told that if your primary work is wood framed structures, it
will not be considered as acceptable experience when taking the SE exam.
Personally, I'd like to know if this is true. Having designed hundreds of
custom homes in my 12 years, I would place the design of custom wood
structures much higher on a level of difficulty than almost any commercial
or retail structure I have worked on.

And if this is not enough, those of us who are opinionated on this issue are
accused of wanting to create a market to line our pockets at the expense of
the homebuyer. Although I don't need to defend my intentions, I persue this
from an ethical standard rather than want of work. In twelve years, I have
never needed to seek out work. I live in a community where I hope to be in
the next thirty years. The homes are diverse - small 1200 square foot
starter homes and half-million dollar custom homes. I personally don't want
to see my neighbor hood reduced to a majority of severely damaged structures
belonging to families that may not be able to afford the minimum deductible
coverage. Nothing can degrade a neighborhood faster than this.

We are told, that the public does not need is another professional to lobby
for work. These misdirected individuals generally don't design homes either.
When an engineer looks for a home in California - how many of them want to
know what kind of protection lies in the walls to minimize the damage
potential in the event of an earthquake? I'll bet none of you knowingly will
move into a home designed and constructed under the Conventional framing
standards that require interior braced panels to be connected to a concrete
slab and terminated below the ceiling.

Consider that most of you will probably not be purchasing a starter home of
this low quality. But, consider the original post that started this - an
area where muli-million dollar homes are being constructed by conventional
framing standards. Would you purchase one of these ?

Vision 2000 has provided the engineering community with a new way to
approach design - performance based. The idea is to allow the client to
choose the level of performance they wish to invest in their project. This
is fine for the owner builder, but I don't share the idea when the clients
intent is to sell the product to an unsuspecting buyer unaware of the
different levels of performance.

Every day I meet potential clients who believe that two houses on the market
are the same. Others believe that when they obtain a home inspection to
close escrow, that the report issued certifies the structural condition of
the home. How many home inspection companys employ professional engineers?
Real Estate agents are also ignorant of the differences in integrity of the
structural elements of the home. Subsequently, they sell finishes -
fireplaces and large yards. To the unsuspecting both are equal.

However, all is not equal - one is engineered and the other conventionally
framed. The engineered home has been run by the numbers and contains as many
shear panels as the conventionally framed home, but has more tension-ties
(holddowns), drags, and other mechanical hardware to insure better
performance. The conventionally framed home - in my area - only has tension
ties located at the piers on either side of the garage door.

You might think that the conventionally framed home is less expensive - not
so. The developer markets it at the same price as his competition of higher
price. He then advertises it as a quality built home. They compete for
amenities, not strength.

The fact is that the public is ignorant. The developer / contractor is
shrewd. Engineers have created the perfect conditions for a scam artist to
act. We don't consider ourselves to be naive enough to believe that every
builder of homes is concerned only with the safety of the buyers - then why
do we provide them with the tools necessary to cheat the public. How much
farther would we need to go to provide (or even suggest) some legislation to
protect the buyer by making the performance based design a disclosure
requirment at the time of purchase?

The real test is how each will perform in a natural diseaster. We can be
sure from past performance that neither home will collapse, but we are also
sure that the conventionally framed home will suffer greater damage and
create eiher a funneling of money from the insurance industry into repairs
(maybe even the contractor that originally built the home), or be sucked
from the savings of the family who now owns the home and has little extra
income to devote to repair.

How dare we, as a professional community, develop performance based design
measures without first insuring against the abuse of the use of these
measures. I think one answer is that residential construction is an
exception to the rule. Developers of large projects typically maintain
ownership and draw income from occupancy. This is true as well of Large
residential projects like apartments. Condominimum and single family
residences, I believe, were never considered while Vision 2000 was taking
shape. On the surface, I support idea of a performance based measure. But we
must be responsible enough to identify the potential for abuse that will be
found in the real world.

We would be far more responsible assuring that some legislation is in the
works to require the disclosure of performance level information before we
try and expand the code into a broader range of residential structures (as
occurs in the '94 UBC and IBC - 1991 UBC was more restrictive).

Finally, the problem stems from those who help create these minimum
standards and who do not activly design residential wood frame sufficiently
enough to learn how the "games" are being played by the developers,
contractors and investors in the real estate market.

It's about time for our policy and decision makers to wake up and address
the problem rather than minimizing the potential problems.

Dennis S. Wish PE