[TowerTalk] US Tower MA 550 Windloading - 90MPH?

[Alan NV8A]

On 09/12/06 10:53 am W7CE wrote:

> Washington State has adopted the International Building Code (IBC) and it 
> appears that many other states are doing likewise.  I looked at the 
> windspeed charts that accompany the new code and, if I'm reading it 
> correctly, the minimum design speed is 85 MPH no matter where you live and 
> obviously higher is some locations.  Here in Lacey (near Olympia), they've 
> adopted 90 MPH.
> 
> Tower manufactures like US Tower seem to be behind the times.  I've talked 
> to them several times and their 130' crankup, which isn't even in the 
> catalog, is the only tower they would spec at 80MPH.  This towers lists for 
> over $40K and they still won't give adequate IBC specs.  For their 106' and 
> 89' models, the highest windspeed that they would spec is 70 MPH.  I don't 
> mind paying for engineering, but I would like to go into it knowing that the 
> manufacturer already believes that the tower is adequate.  Those of us who 
> live in IBC states need to start pressing the tower manufacturers for specs 
> that comply with current laws.  I'd like to put up a 100'+ free-standing 
> tower that can handle 30 sq ft at 90 MPH, and have just about decided to 
> give up on the ham-oriented manufacturers and start talking to the 
> commercial manufacturers.  At least they understand windspeeds over 70 MPH.

Are US Tower's "standard" products (i.e., those shown in their catalog) 
used commercially to any great extent? I see they advertise that they 
can build towers to any specification (which could easily include 
designing for 120mph winds if that's what the customer needs and can 
afford). They also advertise that they have built mobile tower units for 
the military, which (a) probably isn't subject to any municipality's or 
state's building code, and (b) has gobs of money (yours and mine). Then 
there are the hams, many of whom (as it appears from this reflector) put 
"cheap" way ahead of any other consideration and may be the only ones 
buying those "standard" products.

Alan NV8A