Earth rod inside building

[flyingsparks]

Can an earth rod be inside a building? Did a test on a property and the old earth rod (tt system) is now within a small extension they had built.
It's reading is spot on 200 ohms, I am tempted to get pme connected as it is available.

 

[bernardgreen]

Five years ago the DNO had no problems with an earth rod inside a building. Only concern I had was that the ground under the middle of the building might dry out so better that the rod(s) were close to the outside walls.

If the TT is satisfactory then why go to the trouble of changing to PME. PME was "invented" when water pipes went plastic and no longer provided a reliable Ground and the cost of a fourth conductor for an "Ground" through the network was considered too expensive when the Neutral conductor in the network could be dual purpose.

 

[JohnW2]

Can an earth rod be inside a building?

I see no reason why not, and am not aware of any regulation which prohibits it - and I have seen it done a good few times, particularly in outbuildings. Indeed, in that situation it is probably 'better' in most respects than one outside of the outbuilding. The main problem (which may be what you are experiencing) is that if the rod is under a building, the surrounding soil may get very dry, leading to its resistance becoming undesirably high - near the outside wall of a building (but still within the building) would probably be the ideal!

Kind Regards, John

 

[DetlefSchmitz]

A factory local to me apparently has its earth poles right in the middle of the building. They have a regular watering procedure to keep the earth in spec.

 

[securespark]

I have seen quite a few, in terraced TUTD's in Stoke that have subterranean TT supplies.

In my case, I highlighted the installations as dangerous, as the ground they were in was dry and dusty (several 100 Ohms) and the only thing pulling the Zs down was bonding.

 

[flyingsparks]

Thanks for the input, I have gone with the PME connection which is happening tommorow. The current stake is not accessible for inspection and I dont fancy attempting to bang down another one where this is due to the amount of underground services!