I have been following the discussion on bracketed towers especially as it
pertains to Florida construction.
I have never been a fan of bracketed towers in Florida for several reasons.
The first of which is my towers are far too tall for that. Second, in the
lightning capital of the US, I prefer to keep my lightning rod away from my
house as far as possible. Lastly, much of the earlier constrction of the
50s, 60s, and 70s did not tie the trusses together on the bottom chord,
except for where the lower non-support walls were tied in to firm the walls
up. This in conjunction, with the fact that in the old days overhangs of 12
inches or greater were used, tended to really create a huge lateral load.
Many house of this type of construction were blasted away in Hurricane
Andrew, and a new more demanding code was implemented. Lower chords are now
strengthened with plywood and exterior walls have numerous core fills with
rebar.
If a ham has a newer home and ties into the truss, or better yet, the
concrete wall, I believe he would be OK at modest(40 ft) heights. However,
if he is just going to tie into the fascia wood......LOOK OUT. Many of the
homes built before hurricane Andrew incorporate a dropped fascia, which is a
2x4 nailed on end to the plywood sheathing, and then covered with 1x6.
I have seen local hams use this flimsy support for 40 ft of Rohn 25 and a
tribander, and I know of local hams who have lost this type of tower/antenna
setup in less than hurricane winds.
I don't know too much about construction outside of Florida, but I hope this
clarifies things a little for the guys in the land of Chads
Bill K4XS
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