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Re: Housing Performance Objectives

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     I believe that the code writers tried to better define the seismic 
     performance objectives in the 1996 UBC Supplement, Section 1624.1,  
     which states "The purpose of the earthquake provisions herein is 
     primarily to safeguard against major structural failures and loss of 
     life, not to limit damage or maintain function."
     Rick Drake, SE
     Fluor Daniel, Inc.

<<Tim McCormick said: Its cheaper for society to build residential 
structures that maintain occupancy than pay for all of the assistance 
later to help even 5% of them.>>
<<Fred Turner said: Tim touches on a problem with our codes: failure to 
provide consistent seismic performance objectives. I won't try to speak for 
Frank Lew, but many building officials regard the minimum seismic 
performance objective to be life safety only. So as long as a damaged 
building hasn't killed anyone even if its a total economic loss and 
unoccupiable it meets their interpretation of the code's intent. So one camp 

focuses on the "life or limb" clause in Section 101.2 of the UBC to the 
exclusion of other clauses. Historically this
has been the primary focus, but arguably many other code provisions go far 
beyond life safety.
Tim appears to be in the other camp that focuses on the "health, property, 
and public welfare" clause in Section 101.2. But more importantly, Tim 
appears to further clarify his interpretation of the code's intent and 
advocates "maintain(ing) occupancy" in dwellings after disasters. The 
Life/Limb Camp responds to the Property Protection Camp that the role of 
government is limited to ensuring life safety, not the quality of life.
In effect, the UBC states both objectives, so both camps are satisfied 
Policymakers in California are are generally not aware of this debate. Those 

few that are aware of it are reluctant to address this issue for several 
1) unwillingness to face the possibility and the inevitable responsibility 
that parts of the code may no longer meet the public's expectations,
2) loss of competitiveness in high-risk disaster-prone areas if design and 
construction costs are increased,
3) the status quo doesn't appear to need fixing so why rock it;
4) earthquakes are a long-term problem and typical political time-frames are 

less than two years;
5) others (i.e. SEAOC and ICC) are responsible for the codes so its their 
issue, not nontechnical policymakers.
6) the insurance crisis in California has reportedly been solved by the 
creation of the California Earthquake Authority.
7) Northridge was a big quake and we recovered from it well, 
8) FEMA will bail us out after a big one.
Only major changes in the status quo will cause policymakers to rethink this 

issue now. The least that engineers can do is make an effort to counter the 
myths in numbers 5 through 8 above. Its curious how engineers spend so much 
worrying about such small increments in total cost that have such large 
implications without the benefit of knowing what their clients really want. 
the time being, both Frank and Tim have valid concerns because we haven't 
the general public's viewpoint.
Lets hear your comments and suggested ways to address this issue.>>