Driven grounds allowed under house?

[LarryFine]

Is it permissible to drive ground rods in a (tall enough) unfinished crawl-space area, or must they be outside the foundation permieter? Maybe this is one of those if-it-ain't-prohibited-it's-allowed things.

This is a meter relocation, and we'll be placing a 200a main-breaker/disco (to re-feed the exsiting panel with new SER) and a 100a future-needs panel in the stand-up area, back-to-back to the 320a meter base.

Danke,

 

[iwire]

Sure, why not?

I have seen it said that a ground rod should be outside the drip line of the roof so it is in damp earth.

Maybe that is a good idea but it is not required.

In my basement a ground rod driven flush the floor would be at least 6' into the permanent water table.

 

[ceknight]

Maybe this is one of those if-it-ain't-prohibited-it's-allowed things.

It is one of those "if'n-it'ain't prohibited..." thingies, as far as NEC is concerned.

Just to be safe, though, you might double-check your PoCo's specs to make sure it's OK with them. Chances are good that Bob's right -- they'll merely recommend that it be ~3' outside the foundation instead of actually requiring it.

That must be one heck of a crawlspace.

 

[Jim W in Tampa]

Often we install them in the electric room and never had even the poco say anything.It might be smart to ask the poco and ahj first if you have any dought.

 

[benaround]

CEE could be in a similar area without any problems!

 

[goldstar]

Just curious, you mentioned that you are relocating the meter. By any chance did they happan to put on a major addition to the house where they might have installed new footings with re-bar in them? If so, you now have a concrete encased electrode (as benaround mentioned) and you don't have to worry about ground rods. I've had ground rods driven into the earth in a basement with the concrete poured around it, rods driven out on an angle where the wall meets the floor inside a garage, rods driven under a porch before the floor was installed and have never been called on it by an inspector. That's not to say I was right or wrong but the rods do not have to be servicable once they're installed.