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Re: Permit Requirement Question

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>One of my local jurisdictions has recently adopted a policy of "Full
>Design/Single Permit Application". ... 'all' of the design is completed.  In
>particular, I'm referring to building components and sub-systems such as Pre
>engineered metal buildings and WOOD TRUSSES.
>
>...  Submittals would be reviewed and coordinated by the Building designer.
>Lewis C. Midlam
>http://www.lcm.com


Lew:

I've posted this item before, but your question provides a place to remind
our list of paragraph 1.1.5 of the Truss Plate Institute's TPI-85, Design
Specification for Metal Plate Connected Wood Trusses:

"1.1.5  This Specification does not cover design for the complete
structural system of a building.  Provisions shall be made for bearings,
cross and lateral bracing, bracing to transfer truss member buckling forces
to the structure, and bracing to resist wind, seismic or other horizontal
loadings by those responsible for the overall building design." 

So if you specify a prefabricated wood truss system, you do not receive the
web bracing anchorage.  In fact, the Truss Plate Institute publishes some
information on how to calculate the forces needed to resist the buckling of
the web members, but you have to have the loads into the web members in
compression obtained from the truss manufacturer's engineer's calculations
before you can do this.

The point of this is that many engineers, architects and building officials
don't know about this.  Therefore submitting the truss drawings and
calculations after the fact leaves out the opportunity of the responsible
designer to complete the bracing system.  


Neil Moore, S.E.