ECN Forum Forums Code Related Discussion NEC & other Code issues PEX and copper bonding

OK I have a question for you guys…

We are currently roughing a house that uses all PEX tubing (plastic water piping.)

But, at every bathroom/sink/fixture, etc, they transition to copper in the walls.
So basically, we have several isolated copper water “systems” in the house supplied by this nonmetallic pipe.

How would you handle the bonding/grounding of this? I want to bond it all together, is that necessary?

Code requires you to bond the metallic piping if it is likely to be energized. I might argue that a stand alone sink is not likely to become energized.

You could bond it to the circuit that it is likely to become energized by. If that makes sense. If it is likely to become energized at all.

This is not a pool area or hospital room. You do not have a metallic piping system, you have seperate pieces of metal.

If you are going to bond isolated sections of pipe simply because they are metal, don't forget to bond the towel and curtain rods. What about the couplings and connectors for the PE tubing?

If you are going to bond the piping because is near a counter top receptacle, then don't forget to bond the drawer pulls also.

Only if there is good probability that the metallic item will come in contact with an electrical conductor is bonding required. I can not think of a situation that would energize these pipe stubs.

I can think of a situation where the metallic pipe at the sink may be energized, point of use electric water heater, and if it were installed then I would verify that there was an EGC at the equipment to essentially bond the piping at the same time as the heater.

I agree 100% with JBD


No bonding required.

Thanks for the replies guys. I will leave it as it is.

Good to ask Matt but for some reason this question kills me everytime I hear it. Alot of people are quick to jump on the bond wagon without actually thinking for a couple minutes about the situation.

Well, each bathroom has about 20 or so feet of copper in the walls, for shower, sink, etc.

Master is all copper so about 50 feet, but grounded by the steam shower unit.

NM can touch the pipe in some places.

How about the boiler? Allot of copper in the basement but PEX to the AH. So all that is grounded by the 14/2 to the boiler?

It all just seems a little unsafe. All because of plastic pipe.

This thread ponders the question:

How is any water pipe likely to become energized?

What is the criteria for likely?


Dnk.....