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RE: "Blown Away"

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I have just returned from Chicago and need to re-subscribe most of those on
this list. However, I could not help but respond.
The code does not protect the structure but those who may be hurt by the
failure of the structure. I certainly would not want to be the designer of
this part of the structure which may fail and kill someone in it's path to
the ground.
I would seek the advise of the building official who will plan check the
project so as to keep the relationship from "blowing" apart and to justify
your very valid concerns.

The code is specific as to how portions of a building may be treated and you
must consider the safety of those who can be harmed by the failure of the


-----Original Message-----
From: Bill Polhemus [mailto:bpolhem(--nospam--at)]
Sent: Monday, March 05, 2001 7:07 AM
To: seaint(--nospam--at); aec-residential(--nospam--at)
Subject: "Blown Away"

Recently, an architect client of mine and I were discussing a feature of a
commercial building we were working on. He does lots of convenience
food combination facilities. One client has a "doghouse" at the front
of the store, a "penthouse" type structure that allows a sign-logo above the
entrance that extends about eight feet or so above the parapet line.

The doghouse itself is CFS supporting metal cladding, which sits on the
and joists of the main structure.

The design drawings given me showed a CFS structure that was WAY
to resist code-specified wind forces, and I proceeded to design it
which made for a much "beefier" structure, particularly where the roof
and overall connnections were concerned. When he saw this, he had a negative
reaction. "Too much", he said.

I pointed out to him that we were building in an area where the design wind
speed is 120 mph (three-second gust). His response was "oh, that doesn't
if they had a hurricane, the doghouse would just be blown off, and they
build it back again".

I had NEVER heard of this approach before! In essence, he's saying "just
it to handle gravity loads and don't worry about wind, this is not an
portion of the structure. If it gets scoured off, no big deal".

Have any of you designed "components and cladding" type portions of a
under this approach? The architect insists it is perfectly valid: "we do it
the time". Of course, this guy is the "Wal-Mart" of architects in our
and is used by developers here because he works cheaply, and doesn't get in
their way.

I'm starting to rethink my relationship with him on this basis, but I'd like
know if this is perhaps more commonplace than I realize, and if I'm
"overreacting". I just can't imagine a building department anywhere allowing
portion of a structure the possibility of being "blown away".