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RE: "Blown Away"

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Is it normal for you to design "secondary structures" (that is, was it in
your original contract)? If it wasn't in your contract, I suggest that this
doghouse be treated just like the usual Architectural/Miscellaneous metals
and be shown and specified totally in the Arch. dwgs/specs.

This way the Arch 'designs' it or performance based specifies it.  You might
say on your dwg(s): See Arch for All Lt Ga Frmg and Misc Metals.    ?

-----Original Message-----
From: Bill Polhemus [mailto:bpolhem(--nospam--at)swbell.net]
Sent: Monday, March 05, 2001 10:07 AM
To: seaint(--nospam--at)seaint.org; aec-residential(--nospam--at)polhemus.cc
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
store/fast
food combination facilities. One client has a "doghouse" at the front
entrance
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
beams
and joists of the main structure.

The design drawings given me showed a CFS structure that was WAY
under-designed
to resist code-specified wind forces, and I proceeded to design it
correctly,
which made for a much "beefier" structure, particularly where the roof
members
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
matter,
if they had a hurricane, the doghouse would just be blown off, and they
could
build it back again".

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

Have any of you designed "components and cladding" type portions of a
structure
under this approach? The architect insists it is perfectly valid: "we do it
all
the time". Of course, this guy is the "Wal-Mart" of architects in our
market,
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
to
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
a
portion of a structure the possibility of being "blown away".

Thanks.