[TowerTalk] BASE REBAR and Lightning

[Jim Lux]

mecker at peoplepc.com wrote:
> Read that base rebar (which must be electrically tied together)
> should be internal min of 4 inches from edge of concrete base.

That's so the rebar doesn't protrude from the surface of the concrete, 
providing a capillary gap (between concrete and rebar) for water to 
infiltrate.

> 
> Here's my question. (Im learning disabled...etc..etc.)
> 
> What about guys that use a piece of rohn 25 as the base, stick
> the end in the 6 inches of gravel, and then fill up the rest
> with concrete. There is no 4 inches of insulation with the earth
> there, because the gravel has gaps  and moisture in it
> which connect with the earth anyway. (a chemical fact)

Those guys aren't following standard concrete practice (avoiding things 
sticking through the concrete/soil interface)