In response to a reader’s question, we are posting some basic specifications of the Alta, Iowa, elevator that Tillotson Construction Co. built in 1950. (Plans alter between “Tillotson Contracting Co.” and “Tillotson Construction Co.”
The drawings seen above are Tillotson’s standard plan for a 250,000-bushel elevator with eight tanks (silos).
Capacity at Alta was 246,070 bushels. The eight tanks of 18 feet in diameter sat on a main slab of 60.0 by 73.5 feet. The driveway was 13 x 15 feet.
The walls of the tanks rose 115 feet from the slab, and they were topped by the cupola measuring 23.0 feet wide, 61.5 feet long, and 39 feet high. That brought the structure up to 154 feet–quite imposing.
Our Grandfathers' Grain Elevators 
Ronald, Great piece! Here’s the elevator:
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Thanks for providing. Whenever I went out to measure an existing elevator to design and propose an addition, I had to measure what was there in plan and elevation. The one part I “guessed” on was the radius of the head house corners. I always assumed they were the same as the radius of the silos. While that curve radius was not critical to an addition, it was necessary for the several views we would create for the owner to be able to see their facility with the proposed addition. I proposed and built quite a few additions to Tillotson elevators. Thanks.
Chandler Thomas, Consultant 700 Meadow Lane North Minneapolis, MN 55422 Mortenson | Let’s Redefine Possible(tm) http://www.mortenson.com