Bonding a cold water pipe

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deckscrew

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I'm a GC in California. We built a detached Art Studio next to the Main Residence. My electrician installed a 30 amp subpanel to the new unit for the new wiring.

We added a sink with hot and cold water. To plumb the sink we brought a 1/2 copper cold water line to the sink area and brought it in on the exterior of the building and piped through at the back of the sink cabinet. All the DWV lines are ABS. The hot water is being supplied by an undercounter 5 gallon electric water heater plugged into a 20 amp receptacle.

The cold water line has an angle stop with 2 supply outlets. One fitting supplies the cold water to the faucet. The other fitting supplies cold water to the water heater, which then supplies hot water to the faucet. Both lines from the angle stop to the faucet and to the water heater are flex lines. The line supplying hot water to the faucet is also a flex line.

My problem: the Building Inspector is requiring me to bond the hot and cold water pipe, before we can get our final. However, there is no hot and cold water pipe, only flex supply lines. He also offered no solution.

Any suggestions or insight would be greatly appreciated.

Thanks
 
deckscrew said:
I'm a GC in California. We built a detached Art Studio next to the Main Residence. My electrician installed a 30 amp subpanel to the new unit for the new wiring.

We added a sink with hot and cold water. To plumb the sink we brought a 1/2 copper cold water line to the sink area and brought it in on the exterior of the building and piped through at the back of the sink cabinet. All the DWV lines are ABS. The hot water is being supplied by an undercounter 5 gallon electric water heater plugged into a 20 amp receptacle.

The cold water line has an angle stop with 2 supply outlets. One fitting supplies the cold water to the faucet. The other fitting supplies cold water to the water heater, which then supplies hot water to the faucet. Both lines from the angle stop to the faucet and to the water heater are flex lines. The line supplying hot water to the faucet is also a flex line.

My problem: the Building Inspector is requiring me to bond the hot and cold water pipe, before we can get our final. However, there is no hot and cold water pipe, only flex supply lines. He also offered no solution.

Any suggestions or insight would be greatly appreciated.

Thanks
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Have him "cite" the provision in the electrical code. If he's not able, how will he enforce it? Also, just wondering why so little amperage for this studio (30 amp subpanel)...must not be much of a load. Since there's water from the dwelling to this building, does your feeder panelboard wiring method conform to 250.32 with regard to isolated neutral and a 4th conductor for an equipment ground? Is there a grounding electrode system at this building? :) :D
 
By "flex" do you mean non metallic? If so, all I can see that you need to do is run a bonding jumper from your sub panel ground bar to the copper water line. Since it is run to the detached building above ground, it can not be considered a grounding electrode. You will need a grounding electrode system at the detached building consisting of a CEE if available or at the least a couple of ground rods connected to the ground bar in the sub panel. Then, a jumper between the hot and cold lines, if metallic, at the water heater will ensure continuity around electrically isolated fittings.
 
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Thanks for the quick reply.

Its 30 amp because its a small studio (really a glorified garage)

Couldn't tell about the feeder panel, but all rough wiring passed inspection with this inspector. He did run 10-3 (UF?)cable from the house to the new unit.

My electrician said he spoke to the inspector late this afternoon, and that he will require a ground rod within 5' of the subpanel and a ground wire run to the subpanel and the cold water pipe.

I not keen on this idea because the water pipe is 20' from the panel, and we'll have to run wire on the exterior of the building to get to the panel and ground rod creating an eyesore on the front entrance of the building.

I think I'll ask him to cite the code

Thanks
 
This Space(Studio) is Detached or Attached?

Tom

Edited: How many Breakers are in the Panel?

Sorry it is Detached....
 
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deckscrew said:
He did run 10-3 (UF?)cable from the house to the new unit.

My electrician said he spoke to the inspector late this afternoon, and that he will require a ground rod within 5' of the subpanel and a ground wire run to the subpanel and the cold water pipe.
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Now you'll have a parallel path back to the main feeder panel, a violation of 250.32 (B) (2). In this case, he should have run 4 wires to the studio and isolated the grounded conductor from the equipment grounding conductor at the sub panel.
 
10-3 UF is a four conductor cable, so he has a seperate ground wire. Just need to make sure that the grounds and neutrals are seperate in the panel. I don't see any way that you could avoid bonding the copper waterline to the studio panel.
 
Sorry, my bad.:mad: The fact that you ran 10-3 UF gives you the separate equipment grounding coductor. Just keep the grounded conductor separate from the equipment ground in the sub panel.
 
This may be way off base but wouldn't 2 brkrs be a multi or could be reconfigured to a multi, thus not requiring a GE? I guess it's kind of late but next time a 12/3 may suffice in this situation.

Tom
 
Thanks for the replies. I'm going to let the electrician deal with the inspector.

He ran 10-3 because there are 4 breakers one one for the lights, one for the plugs, and two for the electric heater.

One question: why is it required that the hot water, cold water and gas pipe be bonded? Just curious.
 
Good luck, I think it should have a 60A minimum feeder for this detached structure w/more than 2 ckts. 225.39(D) 2005NEC - 02 should be similar.

Tom
 
Davis9 said:
Good luck, I think it should have a 60A minimum feeder for this detached structure w/more than 2 ckts. 225.39(D) 2005NEC - 02 should be similar.

Tom
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225.39 only refers to the rating of the disconnecting means.
 
I got it now. So a 30AOCPD in the House and a 60A rated disco means at detached structure.
I love this job and the site!

Tom:)
 
deckscrew said:
Thanks for the replies. I'm going to let the electrician deal with the inspetor.
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You shouldn't have had to worry about it in the first place.

deckscrew said:
One question: why is it required that the hot water, cold water and gas pipe be bonded? Just curious.
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Consult the NEC.
 
deckscrew said:
One question: why is it required that the hot water, cold water and gas pipe be bonded? Just curious.
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This is a topic that has spurred debate here on more than one occasion. Search the forum for 250.104 and you will likely find many of them.

Essentially, the NEC is especially concerned with metallic water piping systems becoming energized. People handle them frequently.

If the water piping system is metallic, then in must be bonded per the NEC. If is is plastic, and has metallic components, then it is not a metallic water piping system and does not require bonding. However, two people can read the same section (especially in Article 250) and come to far different conclusions.

The NEC is a work in progress. :)

Really, it's best just to let the electrician try to work it all out. He's likely already having a hard time with the inspector, and your attempts to aid in that may only frustrate him further.
 
Well I am the General Contractor and all conditions are ultimately my responsibility. I need to know what all my subs are doing. If an inspection isn't passed it becomes my problem and I like to understand why. It also interests me.

What puzzles me about this situation is that were are being required to run a ground wire from a cold water pipe over 20' away to a ground rod and then on to the subpanel, yet on previous larger job we ran a ground wire between a hot water pipe, cold water pipe and the gas pipe (about 3' of wire) and we were not required to continue on to the panel. I don't understand the difference.
 
deckscrew said:
.

What puzzles me about this situation is that were are being required to run a ground wire from a cold water pipe over 20' away to a ground rod and then on to the subpanel, yet on previous larger job we ran a ground wire between a hot water pipe, cold water pipe and the gas pipe (about 3' of wire) and we were not required to continue on to the panel. I don't understand the difference.
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In your present situation, the cold water pipe is not a grounding electrode because it is run above ground so you are bonding it in case it becomes energized. On the larger job you refer to, I'm sure the water line was one of the grounding electrodes and it was connected to the service equipment at the first disconnect via the grounding electrode conductor. The wire you then installed between the hot, cold and gas pipes was a bonding jumper just as you are installing now.
 
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