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Re: Question on wood Roof Trusses

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	I gather from reading the preceding correspondence on this topic that
there is some confusion regarding he sharing of responsibility between
the engineer of record and the truss design engineer.

	One thing we engineers of record in Canada are doing to reduce this
confusion is this.  We require a letter signed and sealed from the truss
designer confirming that he has inspected the installation and that it
is complete and conforms to intent of his design.

	Since this requirement is part of our specification. and hence part of
the contract documents, compliance is not optional.

	Of coursd, we do still review shop drawings and do our own inspections
to ensure that installation meets OUR design requirements.

	I hope this will be helpful.


				H. Daryl Richardson

Samir Ghosn wrote:
> Let's add to the Mix
> The Designer took a deffered submittal.
> The Building was approved for construction.
> The Building is built and the plans were never submitted to the Building
> dep. for review.
> The building inspector has question the approval since it is not a part.
> The general calls the Mayor and throughs a fit for incompetent staff.The
> general gets the truss plans not signed on an 81/2 x 11 sheets with faded
> print from fax copyies.
> The building dept. has now to approve the truss plans eigh months after the
> permit is issued without the complete package and now figure the load path
> without original clacs.
> The truss design ingnored to include the shear drag collector trusses.
> Oh, there has to be a strap collector or something, but the truss co. not
> responsible.It is the engineer of record problem.Hardware is the
> responsibility of the EOR, not the truss co.
> How many times have you guys out there specified Hardware for Girder
> trusses? just curious.
> Frankly, I have to say, all of the above is true senario and I hardly get
> those plans for review once the permit is issued.  How do building
> Departments control this, Ideas????
> Samir Y. Ghosn, P.E.
> The hrow a twist into this:
> >
> >If I am "responsible" for the bracing, and the contractor/truss supplier
> >never submits the shop drawings, then who is really responsible?
> >
> >I have to beg and plead for shop drawings on commercial stuff, let
> >alone residential.
> >
> >Dan Goodrich, P.E.
> >
> >
> >----- Original Message -----
> >From: "Neil Moore" <nmoore(--nospam--at)>
> >To: <seaint(--nospam--at)>; <seaint(--nospam--at)>
> >Sent: Tuesday, January 16, 2001 12:37 PM
> >Subject: RE: Question on wood Roof Trusses
> >
> >
> >> Tarek:
> >>
> >> If I remember correctly, one of the TPI publications has an example of how
> >> ALL of the webs can buckle at once.  If the web bracing isn't anchored to
> >> something, then this can happen.  Most of the time, the real loads never
> >> approach the design loads and any buckling problem has moved into the
> >> factor of safety area.
> >>
> >> If people are designing trusses in snow areas, say 160 pcf, then our
> >> discussions and the possible reprecussions become important.  My original
> >> involvement in the web bracing responsiblity problem came about 6 years
> >ago
> >> in a court case.  That's were I found out that the responsibility is kinda
> >> hidden in the TPI specification, which the UBC refers you too.  How many
> >> people owned the TPI spec?  Further, it is also difficult to interpret the
> >> results of the computer output.  That presentation can be, and may already
> >> have been, improved upon.  I've read where some engineers are going to get
> >> tough about this and make the truss company provide the web bracing
> >> anchorage to the building or to the roof or somewhere.  Good luck!.
> >>
> >> It still is important to review the truss company's layouts; you might be
> >> surprised at what you will find.
> >>
> >> Neil Moore, S.E.
> >>
> >> >Peter:
> >> >
> >> >I personally have it in my specs that bracing the truss members is the
> >> >responsibility of the truss designer for reasons too numerous to
> >> >recount.this thread was started a while back so check the archives and in
> >> >particular excellent postings by Roger Turk .
> >> >
> >> >I think the bigger problem is getting the framer to actually brace
> >> >the members that need bracing. and unless somebody shows him where these
> >> >members are on the framing plan
> >> >they aint gona walk the building with the little 81/2 x 11's from the
> >> >truss engineer and do it( all they see is a little astrisk next to said
> >> >members)
> >> >incidently every framer that we worked with told me that they have never
> >> >installed such braces and never knew they were even required .Generally
> >> >engineers have some sort of a typical detail on their plans that refers
> >> >back to the truss designer's calcs. good luck getting the framer to
> >> >comprehend it.
> >> >it is my opinion that unless the compression bracing is shown on the
> >> >truss layout sheet with the appropriate details refernced to it nobody
> >> >will follow
> >> >my 2 cents
> >> >Tarek Mokhatr
> >> >strucural engineer
> >>
> >>
> >>
> >>
> >
> >
> >