This seems like a waste of a tower section unless the structure of your
attic specifically matches structurally.
Pressures on the mast are primarily vertical, so the bottom surface must
bear the static weight of the antenna, mast and rotor unless you devise
another rotating scheme.
Lateral pressures on the opening are a function of the wind on the antenna
and mast that allow calculated wind load. This and should be calculated,
and a solution created that fits the space and will support the wind load
and weight.
You can then should be able permit for the combined structure that will be
safe. You can actually design and document a decommissioning process so
that a potential buyer won't run away from you or your family down the road.
Mickey N4MB
“Ends and beginnings—there are no such things. There are only middles.”
Robert Frost
On Tue, Apr 21, 2026 at 11:29 AM Jon Zaimes, AA1K via TowerTalk <
towertalk@contesting.com> wrote:
> Hi Dave,
> Back in the 1960's my best friend's dad was W3ANO in Allentown, PA. He had
> a mast going through the peak of the roof as you propose, with a TA33 or
> similar trapped tribander on it. No rotor though. The mast went through the
> ceiling on the 2nd floor and he had fashioned a brake of some sort and a
> steering wheel on the bottom of the mast in the hallway next to the radio
> room. He would reach up to turn the steering wheel to adjust the beam
> heading, then lock it down!
> You will need a rubber boot where the mast enters the roof to keep water
> out.
> Rohn does have a couple of short top sections:
> https://www.3starinc.com/rohn_25g_antenna_rotor_and_bearing_accessory_shelf_r-bas25g
> or
> https://www.3starinc.com/rohn_25g_top_cap_thrust_bearing_plate_r-bpl25g
> Maybe a bit pricey for your purposes. Any cut-off straight section with
> two accessory shelves would serve the same purpose.
> I have a couple of used top sections with rotor plates in my stockpile if
> you are interested.
> 73/Jon
>
> Jon P. Zaimes, AA1K
> Tower climber for hire
> Felton, Delaware
> http://www.aa1k.us/
> Cell: 302-632-2353
>
> Reviews of AA1K tower work on eham website:
> http://www.eham.net/reviews/detail/12922
>
> Hug your favorite tower every day, and always stay connected to it.
>
>
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