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Re: "Blown Away"

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Projectiles. Do not forget. Projectiles are dangerous, to others, if not directly to
the owner.
Go look at a bill board designs, they have 36 inch steel pipes well embedded.

There are histories of lawsuits for falling signs and injury.

David Merrick

Bill Polhemus wrote:

> 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.
>