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RE: STANDARD PRACTICE/ Plan Checking

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Even the National Association of Home Builders Research Council understands
that construction quality of wood framed structures around the United States
is far from perfect. While they lobby for Prescriptive Conventional
Construction Methods, they aren't ignoring the reality of financial burden
from damage caused during earthquakes and high winds which are generally
caused by a breakdown in the "building" process (design, detailing, plan
review, construction or inspection).

The NAHB-RC started a committee about three or four years ago - Residential
Engineers and Architects Council on Housing (REACH) - whose purpose was to
aid in the mitigation of correctable defects through education rather than
more restrictive codes. The building "team" includes A&E's, Building
department staff (including plan reviewers and inspectors) and the
contractor. By understanding the "inter-play" between building-team members,
errors that currently plague low rise wood construction should improve.

One thing that I find particularly interesting is that while the NAHB
adamantly stands behind the historic performance of Platform and Balloon
Framing (life safety only), there is a failure somewhere in the process that
is reflected by the exorbitant cost of repairs to otherwise preventable
damage. While the argument still debates this high cost of repair as an
acceptable expense based on the intent of the code, the engineering
community seems to disagree and has responded with emergency measures that
were adopted as part of the 97 UBC full-compliance methodologies. I suspect
that what will be found by the CUREe "Woodframe Project" is that many of the
defects are attributed to advancements in technology intending to improve
construction quality but which through lack of education has led to greater
damages. The introduction of mechanical connectors has helped to improve
construction productivity but has also led to abuses such as improper
installation or inappropriate modifications to mechanical connectors that
are not caught in the field. Improper use of adhesives, proprietary anchor
devises, tension straps and other typical load path connectors have led to
many of the failures that were identified in construction damage after
earthquakes and hurricanes.

So what has all this to do with submitting structural analysis? While
calculations are not the only component in the structural design process, it
is the only document that addresses loads specific to the project. As I've
said in another post, the building department staff is not checking to
assure that the engineer is competent, they are acting as a representative
of the public to protect the welfare of those who occupy the building.
Having a license to practice, although possibly showing competence in the
field, doesn't guarantee responsible application of professional skills.
Often outside pressures, design constraints or faulty creative solutions can
influence defects in design and judgment. Although the EOR is ultimately
responsible, the public deserves protection under the code by close scrutiny
of the complete design.

It's my impression that East and West will never come to reasonable terms on
this issue. However, as long as earthquakes and winds are around to shake
out the flaws out of our projects, we might be better off considering that
the more information we provide and the more competent that each member of
the building team performs their responsibility, the more likely that the
quality of construction will improve and the financial liability from higher
risk areas will begin to drop - adding a few extra dollars into our pockets.

Dennis


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