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Does anyone have experience (i.e. can recommend a person to perform this) driving 5/8" x 8' long electrical grounding rods into central HPP (ripped blurock) soil?
John Maloney
310.562.0362
johnmaloney3@me.com
Hawaii Architect AR8082
www.jmagreenbuilding.com
John Maloney
310.562.0362
johnmaloney3@me.com
Hawaii Architect AR8082
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Joined: Sep 2009
Jordan can do that for you. 217-3592
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funny story. I once waited 3 months to get power because HELCO had to hire a contractor to drive in the 8 foot grounding rod. After mamy phone calls to HELCO they sent out a guy who spent 20 minutes cutting the 8 footer to 4 and he drilled and pounded.
Anyway, on my 2nd house I learned you can lay them in a trench. Not sure the depth, I think in my case is had to be more than 18 inches. Much easier.
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I would love to hear how this is done. Having tried more than once myself, I don't see how it can be done unless you have a very long rock drill.
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1. 8 feet buried is a NEC requirement, which County claims to have "incorporated by reference" into the local Codes.
2. There's a guy with a bore rig that will drill a 6" hole 8+ feet deep. Backfill with dirt, install grounding rod, no problem.
3. The alternative is some amount (10-12 feet -- don't have my copy of NEC handy) of bare #8 copper wire embedded in concrete, just lay it down in the form before pouring the garage slab or foundation corner. Take pictures.
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2010 electrical code says 20 feet of #4 bare copper will do in bottom of footing encased by 2 inches minimum of concrete burial. You can also use 2 pieces of 20 foot 1/2 inch rebar placed in bottom, each bent 90 degrees, with "stub" long enough to penetrate top of slab or footing to connect grounding conductor to rebar with ground clamp. Have each piece of rebar go opposite each other down the footing trench, both poking out together to place clamp around.
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2010 electrical code says 20 feet of #4 bare copper
I haven't kept mine up to date -- moving here meant giving up the practice.
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That's cool, just happened to have " the book" handy at the time. Studying the photovoltaic chapter now...
Are you a human being, or a human doing?
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Back to the original question. I have in the past used a hammer drill with the grounding conductor rod "chucked" into head unit to drive it down. Kinda hit or miss on rock density, but beats a sledge hammer on a ladder!
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I paid $150 for a 6" diameter x 10' deep hole -- not exactly cheap, but exactly where I wanted it, and with no risk of injury (sledge hammer on a ladder?!?!)
