Jason,
This sounds like a good plan. I agree completely with the idea of running
long bolts into the 2x8's across the joists. Frankly, install 2x8's as long
as you can possibly get into your attic. Lag bolt them into the joists.
The longer the better as the idea is to spread the load across as large an
area as possible.
I would rather over engineer the thing as well. It NEVER hurts to do that.
And good deal that you don't need professional drawings.
Someone took from my previous rant about permits that I don't advise doing
things according to code. Let me stop that rumor right here. I always
recommend doing everything to code and even exceeding code (eg: code for
grounding a tower structure in my village is one ground rod!). It never
hurts to plan for the worst. The biggest problem with trying to plan
according to code with an antenna tower on the roof is that there might not
be well defined code for such a thing. And if there is, is it designed for
an HF beam? So it never hurts to try to engineer the design to be as strong
and solid as possible. You'll never know if it was "too much", but you may
find out if it's "not enough"!
My philosophy with my roof tower was to make sure some of the small hardware
on the tower broke before my house did!
73,
Jon
NA9D
on 12/8/02 12:19 PM, Jason Hissong at jhisson1@columbus.rr.com wrote:
> I talked with a guy that has done construction for years and he recommends
> reinforcing the 2x4's by bolting 2x6's to the 2x4's (running the complete
> length of the rafter) a piece of plywood would be between the 2 by 4 and the
> 2 by 6. Liquid nails would be used between the plywood and the 2x4 and 2x6.
> Then a stacked pair of 2 by 8s mounted underneath the 2x6s. Long lag bolts
> would extend from the base of the tower legs through to the 2x8s. The
> theory is, the weight/stresses would transfer throught the 2x8 to the 2x6
> beams down to the walls. I would be surprised if this would not be enough.
> I would rather over engineer this.
>
> The city accepts drawings by the homeowner. It does not have to be
> professionally done (although I will do my best anyway :)
-------------------------------------
Jon Ogden
NA9D (ex: KE9NA)
Citizen of the People's Democratic Republik of Illinois
Life Member: ARRL, NRA
Member: AMSAT, DXCC
http://www.qsl.net/na9d
"A life lived in fear is a life half lived."
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