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[SEAOC] Re: [SEAOC] Re: [SEAOC] Re: [SEAOC] Truss discussion.

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Dr. Woeste,

Regarding Neil Moore's question:
> >1.      What if there isn't a building designer or engineer for a project;
> i.e.
> >only the contractor is involved, such as for conventional light-frame
> >construction?  Who now is responsible for the web bracing?

My interpretation of the WTCA-1 is at odds with your response that the
Contractor is the Building Designer:

Citing your quote of WTCA-1, para. 1.2.2: 

>"Building Designer" is the individual or organization having >responsibity for the overall building or structure design....."

and continuing without interruption:

"..... in accordance with the state's statutes and regulations governing
the professional registration and certification of architects and
engineers...... Also referred to as the registered architect or

This stongly implies that the Building Designer is a licensed architect;
or angineer; or archtictural or engineering firm - not a Contractor.

I often have a very similar scenerio:  Although we try very hard to be
retained to provide continuing engineering services during the
construction of projects we design, there are instances (especially on
governmental projects) where the owner retains an independant
construction management firm.  In this case, the original design
professional unually has no involvement during construction.  WTCA-1
para 3.4 requires the Building Designer to "Specify permanent lateral
bracing where indicated by the Truss Designer.", but the Truss Designer
is nearly always a subconsultant to the Contractor, and doesn't even get
involved in the project until after the bid is awarded - long past the
time when the Building Designer is available.

In a similar vein:  WTCA-1 requires the Building Designer to design all
truss anchorage to resist gravity, lateral and uplift loads, but no
matter how the Building Designer lays out a truss plan the Truss
Designer invariably modifies the plan to be as economical as that
particular plant can fabricate the trusses.  For example, one plant may
have a stockpile of Select Structural 2x6's that they'd like to use,
while another plant may have a stock of Grade 2's.  The Truss Placement
Plan, and the load reactions, submitted for approval by the Truss
Designer may be quite different from what the Building Designer had
envisioned.  In such a scenerio, the Truss Placement Plan has to be
summarily disapproved, or someone has to revise the truss anchorage
design.  If the Building Designer isn't involved during construction, is
it the WTCA-1's intent that the original Building Designer 'must' be
retained to do these revisions to his design, or can another engineer be
retained.  But if so, are there many licensed professionals that would
be willing to 'come into the project' so late and become the Building
Designer - and assume the liablility for the whole project.

Thank you for making your WOOD DESIGN FOCUS article available to the sig
members.  It seems to have generated some thoughtful discussion.

Lew Midlam, P.E.
Fort Myers, Florida