I sure wouldn't try it. I don't even trust the fascia board as has been said
here. I also
don't trust the side of the house. Both mine are bolted thru the roof.
If your going to try it on a mobile home, make sure it's done where the roof
meets the wall
at the top corner. That's probably the stoutest spot.
IMHO
Dave
n4zkf
-----Original Message-----
From: towertalk-bounces@contesting.com
[mailto:towertalk-bounces@contesting.com] On Behalf Of AD5VJ Bob
Sent: Thursday, November 15, 2007 8:50 PM
To: towertalk@contesting.com
Subject: Re: [TowerTalk] unguyed with house bracket
No one has answered my question about the Mobile home
Can you bracket to the V at the side of a mobile home or will the mobile
home hold it?
It is a rental and I have permission for antennas, but wouldn't want to pay
for a new wall or anything :)
tnx Bob AD5VJ
> -----Original Message-----
> From: towertalk-bounces@contesting.com
> [mailto:towertalk-bounces@contesting.com] On Behalf Of Jim Jarvis
> Sent: Thursday, November 15, 2007 1:58 PM
> To: towertalk@contesting.com
> Subject: Re: [TowerTalk] unguyed with house bracket
>
>
> Lest the critical info be lost, there was a post which referred the
> Uninitiated to a QST article on how to house-bracket correctly.
>
> Fascia boards are trim, not structure. You must tie into the
> structure.
>
> Using a 2x6 backing plate inside an attic sidewall is preferred.
> But here's an alternative which has worked:
>
> I did not have an attic, it was a flat-roofed house. All I could do
> Is lag screw into the roof joists and the floor joists between the
> first and second floors. That gave me two points of attachment.
>
> My 'bracket' was constructed of 2x8's, 5' long, which spanned
> 3 bays of Roof joists. I used 1/2" x 12" lag screws into the
> 2x12 roof joists, Carefully locating their centers, and pre-drilling
> pilot holes, so nothing split. There were 2 bolts at each of the 3
> joists I intersected. Each bolt was rated for 2700 lbs extraction
> force, and considerably more in shear.
>
> The tower was captured by a sandwich of 2x6"s which were bolted to the
> 2x8 backing beams in question. So, I had the ability to withstand
> something
> >12,000 lbs pullout, and 24,000 lbs shear failure at each of the two
> brackets.
>
> In turn, I calculated the windload with ice, from the antennas and
> tower, and determined that at 90mph, it should be no more than around
> 5,000 lbs at the point of the upper bracket. With a more than 2x
> safety margin, I felt reasonably comfortable.
>
> Let me point out that there were critical measurements involved, and
> that a borescope was used to look at each pilot hole...and that each
> lag screw was installed, removed, the hole inspected for structure,
> and reinstalled.
> You can't be casual about whether you've hit the beam or not, in that
> situation.
>
> And NO, you can't rely on a double-wide at 10' to hold up a tower at
> 40', with any kind of wind. You don't have the overbuilt structure
> that is common with site-built houses.
>
> n2ea
>
>
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>
>
>
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