Bonding Copper Stubs for Plastic Piping

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jevorik

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If plastic water/gas lines are used by the plumber in residential construction, any copper stub outs for faucets and so forth (18" long or more) must be bonded with a #6 wire... correct?

We are starting to see more and more of the plastic lines in my area and I would like to get some input from other electrical contractors.

Thanks
 
If plastic water/gas lines are used by the plumber in residential construction, any copper stub outs for faucets and so forth (18" long or more) must be bonded with a #6 wire... correct?
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Take a look at 250.104(A) for water pipes and 150.104(B) for gas piping systems.

First off if we only have 18" copper stubs at each fixture then we don't have a metal water piping system in my opinion.

So the short answer is NO, we don't need to bond copper stub outs for plumbing fixtures

Also, when required, the bonding conductor for the metal water piping system must be sized according to table 250.66. (See 250.104(A)(1))

Chris
 
jevorik said:
If plastic water/gas lines are used by the plumber in residential construction, any copper stub outs for faucets and so forth (18" long or more) must be bonded with a #6 wire... correct?

We are starting to see more and more of the plastic lines in my area and I would like to get some input from other electrical contractors.

Thanks
Click to expand...
Not correct.

I think that interpretation is gross overreaching.

What code section will you cite?

The nearest that I can find is 250.104(B).

An 18" length of metal pipe on a plastic water distrubution system hardly qualifies as a ". . . metal piping system, ".

If it were determined that a portion of the pipe "is likely to become energized", then it could be bonded by the EGC for the circuit that is likely to energize the piping.

The following kinds of metal piping attached to a plastic piping system are not likely to become energized:

Outside faucet, laundry faucet, water supply to a toilet or sink, shower valve and the metal pipe from shower valve to shower or tub spout. Others can add their own to the list.
 
jevorik said:
If plastic water/gas lines are used by the plumber in residential construction, any copper stub outs for faucets and so forth (18" long or more) must be bonded with a #6 wire... correct?
Click to expand...

Incorrect....


250.104 Bonding of Piping Systems and Exposed Structural
Steel.
(A) Metal Water Piping. ​
The metal water piping system
shall be bonded as required in (1), (2), (3), or (4) of this
section. The bonding jumper(s) shall be installed in accordance
with 250.64(A), (B), and (E). The points of attachment
of the bonding jumper(s) shall be accessible.​
(1) General. ​
Metal water piping system(s) installed in or
attached to a building or structure shall be bonded to the
service equipment enclosure, the grounded conductor at the
service, the grounding electrode conductor where of sufficient
size, or to the one or more grounding electrodes used.
The bonding jumper(s) shall be sized in accordance with...


Metallic fixture stubs are not metallic piping systems. There is nothing to be done, bonding wise, on such an installation. ​
 
jevorik said:
If plastic water/gas lines are used...any copper stub outs .... must be bonded with a #6 wire... correct?
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Let's answer some questions to get the mind going...

What do they get bonded to?
What would be the purpose of bonding them?

I don't think you'll find any copper gas lines ;)
 
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celtic said:
I don't think you'll find any copper gas lines ;)
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Round these parts, copper LP gas lines are used quite a bit. Black iron and CSST are in favor for natural, but LP is quite frequently done in copper, CSST, and black iron.
 
mdshunk said:
Round these parts, copper LP gas lines are used quite a bit. Black iron and CSST are in favor for natural, but LP is quite frequently done in copper, CSST, and black iron.
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LP gas lines of copper are prevalent in rural areas here. They are more common than buried metalic water lines. Clamp an ampmeter around one the next time just for the heck of it. Suprising.
 
This walks hand in hand with the thoughts of bonding around a water heater.

What makes these stubs any less dangerous that the hot and cold water pipes on either side of a water heater?

At what length do they start becoming a system?

If they were all copper and ended in a PVC manifold supplied from a water utility would each pipe be a different system and require bonding?
 
Mike,
At what length do they start becoming a system?
If they were all copper and ended in a PVC manifold supplied from a water utility would each pipe be a different system and require bonding?
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That is a good question. In my opinion if the piping is connected to multiple devices it is a system and requires bonding. A stub connected to a single device is not a system. If the pipes leave the manifold and connect to multiple devices, then they are each a system and require a bonding conductor.
Don
 
I believe the important criterion is whether it falls in the category of "LIKELY to become energized".

Factors to be considered could include whether the isolated pipe is in the vicinity of a connection where a conductor is LIKELY to be exposed in a manner that would energize the pipe.

An 18" stub of copper connected to an instant electric heater at a sink could be considered likely to be energized, and the pipe, faucet, and a stainless steel sink constitute a system that should be bonded by the EGC that provides power to the heater.

The copper piping from a shower valve to the shower head and tub spout, served by non-conductive plastic pipes, or the supply to a toilet or a lavatory faucet, are not likely to become energized, and therefore, are not required to be bonded.

Bonding around the water heater in a metal/conductive water system is a different consideration. The water heater is an element of the water piping system that may insulate one part of the system from the other. The bonding is provided to ensure electrical continuity of the system. The same reasoning could apply to plastic filters and water meters.

On the other hand, bonding around a water heater that is connected to plastic pipe would be absurd. The EGC of the circuit supplying the heater fulfills the grounding/bonding requirement for that component.
 
Bob,
I believe the important criterion is whether it falls in the category of "LIKELY to become energized".
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That wording does not apply to water piping systems...only to other metal piping.
Don
 
Here in lies the question of when they become a system in and of their selves.

I contend that whether they are 18 inches or 18 feet they are not a system by their self. They would be part of a complete system. It is the system that is outlined in 250.104 and no where in the NEC it breaks the system down into parts that needs separate bonding.
 
jwelectric said:
What makes these pipes any different than the 18 inch stubs?
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Maybe nothing, other than the fact that the code language would presently exclude isolated metal sections not part of a metal system.
 
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