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RE: ASD or LRFD for Wood Design

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Ed,
I can't agree with your comments more - however, the issue is really not
construction quality in this case but material economics. The same screwups
will occur whether proprietary members are used or conventional sawn lumber.
The question is whether the methodology creates sufficient savings in
material costs to justify substitution of a quality product in a design that
normally ends up with less than optimum quality of sawn lumber materials?
The main reason I don't specify timberstrand studs is simply cost. The
contractor is not willing to spend 15% more for the materials (or whatever
the differential is). He does not realize the cost difference is actually
less when you consider the savings in scrap and the savings in labor to
straighten bowed walls.
LRFD can not be used (as far as I know) with conventional sawn lumber. I can
be used with manufactured lumber because of the improved tolerances against
defects. If the method creates sufficient savings in over conventional sawn
lumber then it seems justified. If now, I don't see the advantages of
designing LRFD.
Other than this, your comments were right on the money as far as I am
concerned and reflect the same opinions I have for Rigid analysis. Here is
an example that happened just this week on a project for a million dollar
custom home:
I received a nasty email from the architect indicating that the building
inspector was complaining that specific details were missing from my plans.
The contractor accused me of holding up the project and I was being
pressured to drop all other commitments and correct the problem because the
contracted needed to place the slabs the next day.
I called the contractor and met him at the job site. However, I first called
the city inspector and his boss (this is a small town and I am very close to
the building officials.
The concrete sub-contractor changed some of my details for a stepped slab
(12" elevation change). I specified the slabs to be formed and poured
monolithically and the contractor broke them into two slabs (thickened
edges) and doweled them together. On top of this, he placed the Hardy Frames
that I designed for lateral load on the lower slab foundation rather than
the higher side as I specified on the drawings.
It is clearly noted on the plans that the contractor is to notify me of any
discrepancies or questions he may have. If he could not form the slabs as I
detailed, his responsibility was to notify me.
It drove me nuts because I was on the site two days before he poured the
high slab and I asked each sub (concrete and framing) if there were any
questions or anything that needed clarification.

My plans call for a pre-construction meeting but the work commenced before I
was aware that the grading was finished. I was out of the loop until the
city inspector caught the problem.

Fortunately, I was able to justify his change and there was sufficient
capacity in the 13' Hardy frames to handle the shear (although I suppose
that the stiffness has now changed).

How can we build to code standards when contractors are only interested in
pushing ahead and doing the work the way they want - not the way the plans
or details specify.

Yes the contractor is liable, and Yes, I could make him rip it out. However,
this is not in the best interest of the client if his change can be
justified.

We had our pre-construction meeting today. The concrete sub-contractor was
too busy to show up.

Now what are we suppose to do?

Dennis