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Joined: Jan 2018
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I am building a 200,00sq ft warehouse in California with a 2000 amp service panel. My electrician failed to get his UFER ground wire tied into the footing rebar before we poured the footings. This is a concrete tilt-up and the pour back at the walls will be another foot with rebar all the way around. The first part of the footing is 1'-6" deep with continuous #4 rebar. There are #4 slab dowels 12" o.c. that are tied to the continuous footing rebar in 3 places. If I added 20' of #4 rebar tied to these and tied #4 AWG to that also and poured these in my closure strip would that work?
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Joined: Mar 2004
Posts: 947
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You need to let your electrician take care of this.
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Joined: May 2005
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No.
Make your electrical contractor do it right.
Ghost307
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Joined: Jul 2004
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Are there any stub ups from the footer steel that are tied "continuous"? (lapped 24" in the case of #4) If so you can usually tie to that but you need a continuous path to the steel placed "near the bottom or vertically, and within that portion of a concrete foundation or footing that is in direct contact with the earth" (250.52(A)(3) I doubt they will accept a cold joint on top of the footer as being in direct contact with earth. Florida has made the Ufer one of the check offs on the footer inspection to avoid these problems and it has been that way for a couple decades. If you can't find a piece of footer steel you may be chipping your way down to one or coming up with another acceptable electrode. YMMV on that one.
If these "slab dowels" are J hooks with the typical 12" lap on the bottom tied to footer steel, you might find an AHJ with a good enough sense of humor to let you cadweld or even acorn a #4 to several of them up top and call it a continuous connection. I believe it would meet the intent.
Greg Fretwell
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Joined: Apr 2002
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Greg:
Up here, we (Electrical Inspectors) cannot require any chipping or ‘demo’ of a footing when a UFER is missing. That is within the UCC, and alternate electrodes must be installed.
The UFER is the inspection responsibility of the Building Inspectors.
John
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Joined: Jul 2004
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On a service of that size what other made electrode will be acceptable? I am not sure I would be comfortable with 8' rods, no matter how many they drive. If those are hooks tied to the footer steel, I might be OK with several of them bonded to a #4. I think if you get 6 or 8 of them bonded and then pour that second load of concrete I would put that up against anything but a ground ring. BTW I have heard of them requiring chipping down to footer steel here when the #4 was lost/stolen. That is one reason why most AHJs were OK with the turned up rebar solution with a 20' stick snap tied to the footer steel for 15 feet or so and about 4' of it turned up in the wall but that was usually 1&2 family.
Greg Fretwell
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Joined: Apr 2002
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Greg:
Your solution was 'accepted' a few times, as a remedy for a misfortune, or a 'missed' item on an inspector. I tend to seek solutions within the 'real world' as opposed to 'black on white' IF I can.
I've already seen #4 Cu ran and terminated on plastic water mains, jumpers on H&C at water heaters with Pex/PVC piping throughout the house, and a lot of other dumb solutions.
I have no issue with your solution. Yes, I have a few ground rings, and the occasional ground plate. Those are the solutions when there are no other options.
John
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Joined: May 2005
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I have learned the hard way to avoid cutting slack for someone screwing up. As soon as they find out that there is a way that I will accept something lesser as a result of them doing it the wrong way; the wrong way becomes the right way.
Than I have someone standing in front of me whining that "You accepted a different makeshift method before when this happened...why are you insisting that it be done right this time?????"
Ghost307
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Joined: Apr 2002
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Ghost:
I get your points on 'slack'. As I said there are real world solutions (NEC Compliant) to solve issues. For the OPs issue, he should have the issue addressed by the design professional of record. A triad rod setup, ground plate, ground ring, or chip the footing may be required. A 2k service, and a 200K SF warehouse must have approved plans and specs by the local AHJ office.
Let me ad that I slipped off the sizes of the service and building with my previous comments, not realizing the size of the project. I still believe there are solutions to any issue.
John
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Joined: Oct 2000
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From my readings, a UFER is hands down the best earth contact .
Unfortunately, most sparks up my way are contracted after the 'crete is poured.
The state did make a good faith effort to contact most of the 'crete guys , which ended in 'best guess' stub up's where metering and switchgear might end up.
Yet no spark walking into these can prove their viability, so most of us do the whole grounding routine ,and just include the stub in
~S~
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