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Re: Architects Doing Engineering -Enough

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In a message dated 98-05-21 17:22:10 EDT, 73527.1356(--nospam--at)compuserve.com  write:

>  Could it be that houses built under the conventional framing provisions
have 
>  not experienced widespread failures because they have never been subjected 
>  to  the loads for which they should have been designed?
>  Could it be that engineer designed houses are more conservative than houses
>  built under the conventional framing provisions because they are designed 
>  for code prescribed loads?

Roger is onto something, especially regarding seismic loading.  Reality check
for readers of this listserv:  Think back to every detached single-family
house you have lived in the U.S.  It's likely that most of them were of the
non-engineered wood-frame variety.   To your knowledge, have any of them ever
sustained any earthquake damage, before, during or after you lived in it?
It's unlikely.  The reality is that only a very small percentage of such
housing stock ever sustain any earthquake damage, even of the cosmetic
variety, during their service life.  This is true even in urbanized Zone 4
country like the Los Angeles and San Francisco areas.  My mother-in-law's two-
story house in Oakland was one of many that were hastily built in 1907 to help
meet the demand for housing after the '06 S.F. event.  It has a brick
foundation, no anchor bolts or hold downs, and wouldn't calc out or meet
today's codes.  Yet, in it's 91 years of existence, the only damage have some
minor plaster cracks in one living wall, caused by the Loma Prieta event.
I've lived in five non-engineered houses, all located in the Bay Area and
within a few miles of the Hayward and San Andreas faults.  Those houses have
experienced several earthquakes that have caused damage in the region, but
none of those houses sustained any damage.

Readers who can answer yes to the question of damaged houses, please provide a
short post to this thread.  I'd be surprised if more than a dozen responses
appear out of the six thousand members of this listserv.

Frank Lew, SE
Orinda, CA

(I'll skip the motto since Bill Allen referenced it earlier in this thread)