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IBC "Oops" (Was Residential Design Discu

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Permit some comments from an outsider.

Here in Arizona, an area of infrequent large earthquakes (formerly called 
Zone 2), we don't get into the high powered seismic design that you people on 
the west coast do, but I can, and do, appreciate what California Structural 
Engineers have contributed to seismic design.

As each earthquake struck, California Structural Engineers have refined their 
requirements for structural design to the extent that loss of life in the 
recent destructive earthquakes in California could be termed "minimal" 
compared to loss of life in similar earthquakes in other parts of the world.  
It should also be recognized that only a few of the historical California 
earthquakes could be considered "large", i.e., greater than 7.0.  The input 
of California Structural Engineers, and the acceptance into the UBC by ICBO 
is *the* reason that loss of life has been kept so low.

Now, we have IBC, IRC, NEHRP, BSSC, etc., with controlling votes by people 
who have never been in an earthquake, and who have probably never designed 
for an earthquake, determining what the seismic design policies for the 
entire U.S. should be --- the one size fits all concept of the IBC/IRC.  
Based on someone's comment on this list, it seems the consensus process 
requires a unanimous vote, thus someone who hasn't done any seismic design, 
has never seen seismic damage, and thinks that a proposal is too stringent, 
can cause important provisions to not be in the code.

When provisions of the IBC/NEHRP have been incorporated into new structures 
in earthquake country, Mother Nature is going to strike again, proving who is 
in control.  Then it will be a process of reinventing the wheel all over 
again, whereas California Structural Engineers had already invented the 
"wheel" and have been refining it over the past 70 or so years.

As I have complained before, the changeover to the IBC/IRC has been too much, 
too fast, changing to a common code format in one code cycle, and then to the 
IBC two code cycles later.  Nobody really knows what is in the IBC and what 
it really means as it is a hodge-podge of the 3 former model codes.  The IRC 
is a joke in itself as it is merely a rewrite of the BOCA "One and Two Family 
Dwelling Code" which does not correlate at all with the IBC, except that IBC 
Section 101.2 says:

"Detached one- and two-family dwellings and multiple single-family dwellings 
(townhouses) not more than three stories high with separate means of egress 
and their accessory structures ***shall*** comply with the International 
Residential Code." [emphasis added]  

NO option is permitted!  Residences under the IBC are *required* to be 
designed under the IRC!  This is conventional construction run amok!  The IRC 
is a "Referenced Standard" and is automatically adopted when the IBC is 

A. Roger Turk, P.E.(Structural)
Tucson, Arizona

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