>I'm building a new house and want to prepare it for mounting a roof antenna
>"support structure" to the garage.
I think you're going to be MUCH better off with a ground mounted
tower. The 240 bucks that the extra 3 sections of Rohn will cost
you to conventionally mount this tower is going to be cheap compared
to the cost (and headaches, and lack of sleep!) of mounting such
a structure on the roof.
I think for most applications, roof mounts are practically limited
to small to med size roof towers (a la Glen Martin 9' versions)and
even then, there's issues of grounding, etc....
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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