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Re: Permit Requirement Question

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In a message dated 97-11-07 07:01:35 EST, you write:

<< Under the new policy, the building department REQUIRES the submission of a
 statement by the Building Designer that he has reviewed and coordinated all
 sub-systems, sub-assemblies, and resulting load-paths.  That's  not an exact
 quote, but it is their intent that they want 'all' portions of the design to
be
 fully completed and coordinated 'before' a permit is applied for.
 
 I'll be discussing this issue at a meeting with the building department late
 next week and I'd  like to know if the are other jurisdictions with a
similar
 policy.  
 
 My question to the list is this:  How many other jurisdictions have similar
 requirements?
  >>
     County of Ventura , CA( but not necessarily cities in the county ) ,
city of Santa Clarita are two i have delt with recently that require this. 

     I see merit with this as i have had trusses installed before i have
recieved the truss calcs for approval . In some cases the truss calcs were
wrong. A common omission is a bending plus axial check of members.
     Also, i would encourage the engineer of record to insist the truss calcs
AND layout be signed by a licensed engineer. I believe too many truss calcs
are being done by truss company technicians ( high school grad or ? ) and
being sent to be rubber stamped. There seems to be many new companies jumping
on the bandwagon but i remember some old ones going out of business in the
last recession. The truss company will resist signing the layout but will
comply if you stand up. They may say your the only one requireing this but we
had this discussion before and many engineers require the truss company to
stamp and sign the layout as well as the profile and calc's. I do.
     Another area, while were on the subject is truss bracing. I have yet to
go to a job that has all the truss company required bracing properly
installed when i do a framing structural observation. No one at the jobsite
seems to know what those little asterisks or dollar signs mean. Also , double
or triple girder trusses may not be laminated in the factory ( 10d @ 2" O.C.
) and the field guys don't know to do this.
     Three years ago i had a call back on a five year old tract we engineered
about some roof deflections. In the attic i noticed some odd lack of bracing
so i called in the truss company, Hanson truss who i feel is first class and
has an engineer on staff ( who stamps and signs the layout plan ). That
engineer pointed out that the top chord bracing had been omitted and the hip
girder trusses where on the verge of collapse. This was repaired at minimal
cost by the original contractor. After this i wonder if the truss company
engineer should be part of the structural observation program.
     Requireing truss calcs at initial submission is something of a catch 22
though. The truss company does not want to provide engineering until they
have a contract and the owner usually does not want a contract/ bid until he
has a permit. The software is not available to the design engineer of record
because the truss plate companies develope and only distribute to truss
companies who buy thier plates, as was explained to me.
     The county of Ventura advised me to design the building for a
conventional roof and then come in with a change for the trusses. This is not
only double work but trusses usually span differently than conventional
framing, potentionally overstressing a beam unless the whole building is
reengineered. Also, shear transfer detailing may be different.  The county of
Ventura has basically rejected the concept of deferred submittals ( UBC Sec
106).
     One observation: i provided evaluation reports on over 1000 residenses
after the Northridge earthquake and i found truss roofs did significantly
better holding together than conventional framed roofs.
     There may not be an easy answer but it is clear to me the status quo on
wood roof trusses is low quality at the installation end ( not the
manufacture ).

    Tom Harris , SE
    Thousand Oaks, CA