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Conventional Framing Concerns - A letter to NAHB

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To Mr. Jay Crandell
HATDE: Housing Affordability Through Design Efficiency
National Association of Home Builders
(1-800-638-8556) or jcrandell(--nospam--at)nahbrc.org

I would like to invite you to join the SEAOC Listservice. It is very
beneficial that you do since many of our discussions relate to our
professional concerns over the inadequacy of Conventional Framing standards
in High Wind and Seismic areas of the country. There is no charge to join
the listservice. You need only send an email message to admin(--nospam--at)seaoc.org and
in the body of the message type "join seaoc" (without the quotes).

FOR SEAOC LIST MEMBERS READING THIS POST, PLEASE REFER TO NAHB WEB SITE FOR
NATDE AT http://www.nahbrc.com/homebase/techbrfs/hatde.htm.

I suggest you visit the SEAOC web page at seaoc(--nospam--at)seaoc.org and work your way
to our listservice archives. Please search the topics for Conventional
Framing and our latest thread entitled "Architects doing Engineering".
We have some very strong issues with the Conventional Framing Section of the
'94 and '97 UBC. Our concerns are not diminished much by the draft of the
IBC - however, many of us feel that it is an improvement.
Some concerns include:
1) The lack of completion of prescriptive measures to guide non-professional
users of this code. For example, where in the code does it provide
prescriptive tables for the design of headers.
2) A non-engineered prescriptive measure in the code should allow for the
minimum standards of safety that are equivalent to or exceed an engineered
solution. The current provisions of Conventional framing provide a much
reduced minimum standard for building products produced under this code
provision. This will equate, not in life safety issues, but real economic
concerns as the cost of repair exceeds those of damaged engineered products.

Jay, I am not trying to sell engineering over prescriptive measures, but am
trying to assure that the provisions that the non-professional follows is
equivalent to an engineered solution and provides enough information to
adequately build the structure and minimize the chance of structural failure
or unreasonable potential repair costs.

One issue that the code creators did not contend with is the lack of
disclosure provisions that educate the potential home-buyer as to the level
of performance that the home was designed for. I live in the Palm Springs
California area and specialize in residential construction. Many homes in my
neighborhood are constructed by developers who follow Conventional framing
standards to maximize their profits. They market their homes in the same
price range as comparably sized engineered homes, but lack the holddowns,
anchor bolts, and shear resisting elements required by engineered standards.
Considering the floor plans are equivalent (there are only a number of plans
that can be constructed on a 50' x 100' lot) the engineered product with a
base shear in seismic zone 4 equivalent to 0.133Wd compared to a wind load
based upon a wind force of a 70 mph wind with Exposure C will require a
greater number of holddowns and greater shear resistance at interior braced
panels than those following Conventional Framing Provisions.
The developer, however, advertises a full code compliant structure and
falsely claims it to be equivalent to every other home in its size and price
range.
The public invests in these homes unaware of the cost potential down the
road when the conditions are right and the home is subjected to a moderate
or large earthquake or Tornado (or Hurricane).
Legislation to provide a performance rating on homes would greatly help
accomplish the following potential improvements. The advantages may not seem
obvious at first but should include:
1) lowering the profit margin of the developer /owner by true comparison of
the structural performance between competing structures. If the developer
wishes to maximize profit at the expense of performance, the public who must
burden the expense of repair has the right to know.
2) Disclosure may help improve the minimum standards for performance above
the level of Conventional Framing by public demand. Personally, I believe
that the home owner would choose to pay a 0.5% or 1.0% increase in
construction cost to improve performance and reduce the personal liability
when the event occurs.
3) Improved performance or disclosed rated performance may create an
incentive for reductions in insurance rates. This is not possible today
since the level of performance is unknown to the Insurance Carrier unless
the home was constructed to some minimum level of compliance such as those
required under a Fanny-Mae or HUD loan. Private lenders do not care what
level of performance is followed so long as it complies with written code.
4) Advertised homes can use the level of performance as a marketing tool to
promote sales. At this time the uninformed home buyer believes that all
homes are built equal and that code compliance protects them from excessive
damage as well as loss of life. This is why so many home owners are angered
when they learn that a home performed as expected by code in spite of the
level of structural damaged it suffered.

Jay, this is a vastly debated topic. The SEAOC Listservice has 6,000
subscribers world wide. We feel that the list is a growing voice which
represents the needs of the vocal community. We feel that NAHB needs to
encourage a partnership with engineers concerned with these issues.
Membership affiliation is not enough when engineers have no idea who is
carrying the ball in the code creation cycle. We also feel that there are
many benefits to the Insurance industry which creates a strong allies with
the home building associations, structural engineers and architects that can
instill change for the benefit of the general public.
Please don't misunderstand. Structural Engineers Association of California
has taken a valiant effort to improve the provisions of the code, but many
of us feel that they do not have sufficient voting power on the ICBO floor.

The conventional framing section of the Uniform Building Code is incomplete
and contains some serious deficiencies that the local building officials are
powerless to enforce. In my town (La Quinta California) developers are known
to place undo pressure upon the local city council with threats to move
their development to another town unless the building official allows
compliance to conventional framing based upon the developers interpretation
of those missing or confusing sections of the code. For example, the section
on interior braced wall panels fails to prescribe the connection of the wall
to the structural diaphragm.
ICBO has completed the last edition of the '97 UBC and will offer no
revisions to this inadequate section - devoting their efforts on the
creation of the IBC. The IBC, on the other hand, will not be adopted by
local municipalities until approximately three years after it's initial
publication or 2003 the earliest. So, for the next six years, the followers
of the prescriptive method will be allowed to construct useless or
ineffective shear connections of interior braced panels.
These are only a few of the inadequate provisions of the code.

I would be willing to devote time to HATDE with the understanding that we be
allowed to post committee work on the SEAOC web or open the floor of
discussion on the committee work to the engineers who subscribe to the SEAOC
Listservice. This creates a channel for International engineers interested
in having their opinions heard but how do not have the channel to do so.

I urge you to enter into this discussion on our List and use our combined
knowledge and experiences to help create a better prescriptive code for the
non-professional to follow.

I am active with both SEAOC and LGSEA (Light Gauge Steel Engineering
Association - http://www.lgsea.com - which I believe NAHB is intimately
familiar with.

Please understand that are motivation is the protection of the public. We
feel that the intent of the Conventional Framing section of the code is
being used unethically to increase the builders profit at the expense of the
welfare of the general public. SEAOC's Vision 2000 promotes a performance
based code methodology. The difference is that the owner will have the
control of performance. The general home-buying public is at the mercy of
unscrupulous developers who use the provisions of Conventional Framing to
line their pockets and the ignorance of the general public to cover up their
actions.

It is important that Structural Engineers have the lobby power to make
constructive changes to the code for the benefit of the public. Your help in
this matter is greatly appreciated.
I have taken the liberty of forwarding a copy of this letter to the SEAOC
Listservice so that the many engineers involved in this discussion will be
aware of your awareness of our concerns and the possibility of our
involvement in our list.

I thank you in advance for your attention to this matter.
Sincerely
Dennis S. Wish PE
La Quinta, California
wish(--nospam--at)cwia.com

ICQ# 6110557
http://wwp.mirabilis.com/6110557

"The greatest pleasure in life is doing what people say you cannot do."
Walter Bagehot