Installation of Ground Rods

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mike grisofe

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Over the years when building residential services I seem to always find the biggest rock when driving a ground rod. Older homes in are area must have had all the debris from construction backfilled around the fondation. To avoid most of the debris I have driven the rods horizontally through the basement wall 30" or more below grade. There are additional reasons for this approach,
1) The rod location dosen't present a trip hazard and won't be hit by the lawn mower.
2) The possibility of the connection of the GEC to the rod is more likely to remain as installed.
3) When it below freezing I would rather be inside driving a rod below the frost line rather than through it.

What is your opinion? I'd like to have comments by Electrical Inspectors. Thanks
 
My only comment it that it's a violation to install the rod as you've mentioned. It must be installed as outlined below:

250.53(G) Rod and Pipe Electrodes. The electrode shall be installed such that at least 2.44 m (8 ft) of length is in contact with the soil. It shall be driven to a depth of not less than 2.44 m (8 ft) except that, where rock bottom is encountered, the electrode shall be driven at an oblique angle not to exceed 45 degrees from the vertical or, where rock bottom is encountered at an angle up to 45 degrees, the electrode shall be permitted to be buried in a trench that is at least 750 mm (30 in.) deep. The upper end of the electrode shall be flush with or below ground level unless the aboveground end and the grounding electrode conductor attachment are protected against physical damage as specified in 250.10.
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mike grisofe said:
..... To avoid most of the debris I have driven the rods horizontally through the basement wall 30" or more below grade. ....
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You pass inspection with this method?

You don't create flooded basements with this method?
 
I agree with Trevor and Ken.

1) The rod location dosen't present a trip hazard and won't be hit by the lawn mower.
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What length of grond rod are you installing? As Trevor pointed out a ground rod must have 8' in contact with the soil, so unless you are using 10' long ground rods you should be driving the ground rod below the surface of the ground. If you do this then there is no trip hazard and the lawn mower won't hit the rod.

2) The possibility of the connection of the GEC to the rod is more likely to remain as installed.
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Again if you drive the ground rod to below grade then the connection should not be disturbed.

By the way welcome to the forum.:)

Chris
 
mike grisofe said:
Over the years when building residential services I seem to always find the biggest rock when driving a ground rod.
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Have you tried driving a foot away from the house? The footing is usually required to be at least twise the foundation thickness. For example, an 8" brick/block wall requires a footing at least 16" wide; they usually go 24" so it doesn't have to be dug perfectly straight or placed.
 
I have often wondered why it is acceptable to drive a ground rod so close to the foundation,.. all the drawings of the sphere of influence that a ground rod has show a circle ,.. when we drive them next to the foundation don't we have half a circle??? Therefore less effective ground rods ??.....
 
M. D. said:
when we drive them next to the foundation don't we have half a circle???
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That depends on how deep the foundation is. Even then, if concrete can be used as an electrode (Ufer), how badly would it reduce an electrode's functionality?
 
LarryFine said:
That depends on how deep the foundation is. Even then, if concrete can be used as an electrode (Ufer), how badly would it reduce an electrode's functionality?
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Don't know ,..just thinking out loud
 
LarryFine said:
...AND you have a proper electrical connection to it. ;)
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right ,...so how does it help in regard to my question , if there is no connection ??? In other words it is the copper or the steel which is in direct contact with the concrete which is in direct contact with the moist mother earth ,.which is the electrode not simply the concrete.
 
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