Doug Miller wrote:
In article , Bud-- wrote:
Doug Miller wrote:

Not obvious if you are saying there is no grounding electrode at the
shower building. It is code required. Rods are notoriously poor, but the
easiest if an electrode is not now present. Code is 8' (as someone said)
and 2 are usually installed.
Actually, Code is 8' or to the depth of permanent soil moisture, whichever is
deeper. [Article 250.53(A)]
250.53-A is installation and is not whichever.

250.53(A): "Where practicable, rod, pipe, and plate electrodes shall be
embedded below permanent moisture level."

250.52-A-5 has requirements for the electrode - min 8'.

Note the word "minimum". Clearly, if the depth of permanent moisture is at,
say, 10 feet, and it is "practicable" to drive a rod to that depth, 250.53(A)
*requires* doing so.


I misread your original post as 8' or moisture whichever is less. What
you wrote, whichever is greater, is right and is a good practice.

I doubt you usually know the depth to permanent soil moisture, which
makes the article a little hard to enforce. And I doubt it is enforced.
Fortunately the move is, in general, to Ufer/concrete encased
electrodes, which are far better electrodes.

Anyone been required to use a ground rod more than 8' in the earth?

--
bud--