On Wed, 4 Jan 2017 10:31:06 -0800 (PST), trader_4
wrote:

On Wednesday, January 4, 2017 at 12:58:25 PM UTC-5, James Wilkinson Sword wrote:
Somebody in one of these two groups recently said that a concrete based house means you're earthed. Concrete is a bloody good insulator!

Sorry, can't find the post it was mentioned in.



Wrong as usual. Concrete that's been cured and then dried out,
kept away from moisture, may not be a good conductor. But building
concrete, a foundation is such a good conductor, it's the preferred
ground for the building electrical service. An electrode is placed
inside it before the pour.

Best I can tell, my foundation has an Ufer ground. Inside the
exterior wall there is a ground rod going down into the concrete.
Might be tied into the cable tension cables in the foundation. This
is in the desert.