Bonding short sections of copper water pipe

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Bonding short sections of copper water pipe

  • Bond

    Votes: 1 5.9%

  • Do not bond

    Votes: 16 94.1%
  • Total voters
    17
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B

bassphisher

Member
I am inspection a house that is plummed with (PEX) plastic water pipe for the home runs.Once the PEX gets to a bathroom it is crimped to copper,and then the whole bathroom is run in copper water pipe.Shower sinks ect.So their is a substantial amount of copper in each bathroom.
If I ask the electrician to bond the copper back to the service am I going overboard? I am looking at section 250.104,Then read 250.104(A)(2) I realize that the second code section is for multiple occupancy buildings but it seems applicable.
 
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Boy this one is certainly open to interpretation.

IMO no do not bond, the bit of copper in the bathroom is not a metal water piping system. It is part of a PEX water piping system.

Thats my story and I am sticking to it.;)

Also would you consider this copper at all 'likely to be energized and by what?

As some have said on this forum about bonding some items.

'Now you have brought one conductor of circuit that could electrocute someone'.

JMO, Bob
 
bassphisher said:
I am inspection a house that is plummed with (PEX) plastic water pipe for the home runs.Once the PEX gets to a bathroom it is crimped to copper,and then the whole bathroom is run in copper water pipe.Shower sinks ect.So their is a substantial amount of copper in each bathroom.
If I ask the electrician to bond the copper back to the service am I going overboard? I am looking at section 250.104,Then read 250.104(A)(2) I realize that the second code section is for multiple occupancy buildings but it seems applicable.
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If it is for multiple occupancy buildings than it just plain don't apply to a single family house.

I voted no but on reflection I can see how section 250.104 might well require a bond. The code does not define the term "metal piping system", so it would appear to be open to interpretation. I don't see how an isolated short length of pipe can be considered a system, but an interconnected group of them might be.

By any chance is this connected to a spa type tub? Wouldn't that change things a bit?
 
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It depends. If there is electical that could energize it, then you should ensure a bonding means. Example would be insta hot water heater.

The code does not specifically address "partial metal piping systems"

You could require a positve bonded connection to the EGC of the branch circuit supplying the insta hot, if it is not already bonded inside the heater.

Without the electrical equipment above, I would say bonding not required.
 
sandsnow said:
It depends. If there is electical that could energize it, then you should ensure a bonding means. Example would be insta hot water heater.
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If there were a circuit likely to energize the isolated piece of copper pipe in the nonmetallic system, such as an insta-hot, then it should be bonded to the circuit's EGC. If it were a one-location insta-hot (such as you might find integral to a showerhead, etc) then it should be bonded through connection to the heater.

It should be only considered potentially energizing the metallic pipe connected to it, not remote pipes isolated by PEX, IMO.

Petersonra said:
By any chance is this connected to a spa type tub? Wouldn't that change things a bit?
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Only prior to the 2005. :)
 
Bonding of Pipes

Bonding of Pipes

Bonding is required for a metal water piping system.
1. If its not metal then its not a system
2. What is going to energize a metal stub by the toilet?
3. The Insta Hot if installed would have its bonding done by its supply circuit as allowed per 250.104

In Washington State we have a state code rule; Bonding is not required for isolated metal piping stubs from a non metallic piping system.
 
Something I've been curious about for some time: With an electric WH of any kind with proper bonding; is the fault path through that bonding good enough? Is that ground path better than one through the sewer line or line going to septic system. What kind of potential will you have through the water to say shower head with respect to the drain line?
 
I've seen a few reports on various forums about people being shocked between water pipes and drain pipes, say taking a shower and touching the shower controls.

Given this, I am strongly inclined to make sure that all metal fixtures in a bathroom were bonded together, even if there was no bond back to the electrical service, or a bond only to the 'egc of a circuit likely to energize'.

I don't think that I can back this up with a code reference...but it is something that I will specify as a customer when I next have a bathroom done :)

As an aside, do you consider metal drain pipes to be metal water pipes which require bonding? Do you consider them underground metallic piping systems, which therefore must be bonded as available grounding electrodes?

-Jon
 
Almost the same question came up in one of our IAEI meetings. They wanted to know if you had to bond the faucets if the house was piped in PEX.

I say no also. You gotta draw the line somewhere.
 
winnie said:
I've seen a few reports on various forums about people being shocked between water pipes and drain pipes, say taking a shower and touching the shower controls.

Given this, I am strongly inclined to make sure that all metal fixtures in a bathroom were bonded together, even if there was no bond back to the electrical service, or a bond only to the 'egc of a circuit likely to energize'.
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Even though one of the conversations in question involved an open neutral, a bonded metallic water system, and a plastic drain which completed the circuit, resulting in a shock?
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As an aside, do you consider metal drain pipes to be metal water pipes which require bonding?
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Only if likely to become energized. 250.104(B)

Do you consider them underground metallic piping systems, which therefore must be bonded as available grounding electrodes?
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They are not required to be used. 250.50 requires (1)-(6) to be used, and (7) is an optional grounding electrode. Metal drains would fall under 250.52(A)(7), IMO.
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Here the AHJ doesn't require it. 'doesn't require bonding of metal towel racks, either.
 
georgestolz said:
Even though one of the conversations in question involved an open neutral, a bonded metallic water system, and a plastic drain which completed the circuit, resulting in a shock?
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Well, duh! Clearly someone forgot to run the minimum 3/8" braided polypro from the drain stack to the service neutral. :)

-Jon
 
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