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RE: Valley Rafters

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I've got an interesting story on this.  Some of it's second hand, so I
can't verify all the facts.  But just the other day...

A client designed a roof, architecturally speaking.  The owner took it
to an engineered lumber supplier, who did all the calcs and the
roof/floor framing layout with I-joists etc (they're doing more and more
of that, you know - really don't need us for that).  The owner looked at
the package and was horrified at the 16" LVL valley beams.  He took it
to the local building official and asked if it was too much.  The
building official basically said "oh you can stick frame this with 2 x
12s and such."  (never mind that they'd need to order 26' long lumber
for the rafters).  And the building official offered to size down the
members...  (and at this point I said "what???")

I've got to believe the B.O. really didn't say that.  But at least they
weren't clear in their offer of help.  What's the point of the story?
It's not as much about valley beams as it is about consistency.

Lack of consistency can wreak havoc.  The code has become so complex.
For houses not only is there a prescriptive section for wood framing,
but we have it for cold formed, for ICF, for post-tensioned petrified
wood, for (fill in the blank________).  Not that it's all bad.  But many
of the plan reviewers simply aren't qualified to make structural
decisions, much less understand all of the code.  And so we get all
these crazy stories about what goes on.  Then there's the inspectors,
who can't really be expected to catch everything or deal with it
properly.  And then at the other end of the spectrum is the PE/SE/Phd
plan reviewer who requires you to provide approximately 3 times the
quantity of calcs, and academically strikes down your brazen attempt to
apply engineering judgment to a situation where the code doesn't
explicitly list your solution.

What fun!  

Ed Tornberg
Tornberg Consulting, LLC

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