[Boatanchors] TOWER INSTALLATION

[Bill & Liz]

Burying a tower or installing it on legs unless in concrete is definitely bad practice, especially if the soil is in any way acidic.  Up this way a lot of fellows have buried the first 4 ft of a tower section in very sandy soil, but that has good natural drainage and the practice is quite permissible as long as the stub/tower is coated with protective material.

When I climbed as part of my business I was always careful to see if the base of a free-standing tower was in concrete with no earth piled around it.  Once I did not inspect the tower base carefully enough-it had thick vines growing around the bottom-should have been a clue.  I climbed to replace a base station antenna on top and about a month later I received a call from the owner saying the tower had toppled over and he needed a new one.  I discovered that the wife had covered the original base with a deep layer of topsoil which I did not see because of the vines.  The acidity in the soil ate away the legs...it’s a wonder the tower did not come down with me on the top!

Due to the cost of concrete it is becoming common practice when installing a tower meant for light duty to drill three 5 ft deep holes with an auger and place sonotubes in the holes.  The top foot or so is criss-crossed with rebar tied together and then concrete poured in the tubes and across the top, covering the rebar.  This reduces the cost of installation substantially but I would not wish to rely on this method if the tower is to carry any kind of load. 

Bill VE3NH