View Full Version : Home ground rods
questionground
Oct 15, 2009, 02:37 PM
Please help I have been trying to find out how many grounding rods are required to be installed on the outside of a home?
Ideally I would like to find the electric codes that specify how many grounding rods are required and if more than one; how far are they apart are they placed? :confused::confused:
I would be grateful for any help.:)
Thank you,
KISS
Oct 15, 2009, 03:28 PM
One. Per, then 5/8 dia 8 foot long. Preferably below the water table. Local codes could dictate otherwise.
If more than 1, then no less than 6' apart.
In addition, any subpanels on dettached structures require a ground rod
See NEC 250.50 You can read it for free online by following the sticky under "Electrical & Lighting" in the link on the top left of this post.
Furthermore, there are requirements for bonding the water and possibly gas piping systems.
stanfortyman
Oct 15, 2009, 03:51 PM
Please help I have been trying to find out how many grounding rods are required to be installed on the outside of a home?NONE are "required". A grounding electrode is required, but nothing states this must be a rod type electrode.
In new homes where rebar exists in the footings the rebar MUST be used as a concrete encased electrode. If this is the case NO other electrodes are required.
If you do use a ground rod, and you cannot prove that one electrode has a resistance of 25 ohms or less then ONE more supplemental electrode is required. Thing is, the tester to perform this test is over $1000 so most electrician simply sink two and are done with it.
KISS is right on, of two are used they must be 6' apart.
seanmkie
Oct 15, 2009, 06:30 PM
Two ground rods 8' down in the earth 6' apart.
ballengerb1
Oct 15, 2009, 07:25 PM
Most rods are 10' and no matter the length they should reach the water table. Call your local building inspector to see what he will look for since he would do an inspection
stanfortyman
Oct 16, 2009, 04:03 AM
Most rods are 10' and no matter the length they should reach the water table. Call your local building inspector to see what he will look for since he would do an inspectionActually "most" ground rods are 8' long, and how would someone know if they reached the water table? And what would it matter?
I think most people have a very incorrect view as to what ground rods actually do.
Hint: They have nothing to do with tripping breakers or short circuits.
stanfortyman
Oct 16, 2009, 04:04 AM
two ground rods 8' down in the earth 6' apart.Yes, IF you install them this is the requirement, which has already been stated.
deon crowder
Nov 20, 2009, 05:30 PM
How do I wire the ground rod to the main
stanfortyman
Nov 21, 2009, 05:40 AM
how do i wire the ground rod to the main
You run a wire from the ground rod to the main panel and connect it.
If you notice, I just answered your question with the same level of detail as your question. ;)
Can you maybe describe a little better what it is you are doing? WHY are you adding a ground rod? Is this a new service? Is there a water bond in place?