PEX vs Copper....Bonding??

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mcintoshmc

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My house is currently only grounded at the panel, but not at the receptacles in the home. I was all set on purchasing my PEX supplies here shortly for my home run system, but my retired electrician neighbor, who has been against me going PEX from the beginning, finally came with argument that's making me reconsider.

Eventually I am going to ground the home, and I won't be able to tie to old galvanized or copper pipe because it won't be bonded, so I would have to run a line from each directly to the panel, making the job that much more expensive.

As I was writing the post it occurred to me that I could go copper for my line in to just under the wall where my manifold will be, and then run a PEX riser to the manifold.

Will that fix my issue?
 

Beni

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Not exactly. In olden days (before PEX and CPVC), electricians would run a ground wire from the panel to the water line entrance. The metal water pipe, provided an easy earth path for the ground wire. The piping its self does not need to be grounded.

So with plastic water pipe, you will need to use a 10' copper ground rod buried in the ground and connect the ground wire from the panel to that. No where in the NEC or plumbing codes does it require water lines to be grounded, BTW.

BTW, I'm a engineer and while I use to think copper was king, now a days I believe that PEX is actually superior to copper.
 
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IFIXH20

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We have an Electrician do a reground (new ground) on all our repipe jobs, the Electrician runs a grounding rod in the ground and a copper wire from rod to panel. (our residential repipes are cpvc usually)
 

Caduceus

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Please try not to misinterpret what I'm saying, but you may need to call a more modern electrician. I can understand that cost is an issue, but when you state that you consulted your "retired electrician neighbor" and he was "against going PEX from the beginning" I have to consider that he really doesn't know how to approach the situation. His knowledge may be limited to restricted circumstances.
That being said, more options are available because of the more common use of plastic piping when it comes to grounding. I frequently consult an electrician, to be safe, because I've been shocked by questionable electrical grounding in the past. There could be a detail about your wiring that we can't see here that could be a game-changer when it comes to safety.
Other than that, most electricians I know would run a ground to the copper service, before the transition to plastic.
 

Caduceus

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Not exactly. In olden days (before PEX and CPVC), electricians would run a ground wire from the panel to the water line entrance. The metal water pipe, provided an easy earth path for the ground wire. The piping its self does not need to be grounded.

So with plastic water pipe, you will need to use a 10' copper ground rod buried in the ground and connect the ground wire from the panel to that. No where in the NEC or plumbing codes does it require water lines to be grounded, BTW.

BTW, I'm a engineer and while I use to think copper was king, now a days I believe that PEX is actually superior to copper.
Also, what Beni said.

As a side-bar @ Beni.

I believe that there is a time and place for plastic as well as copper. Superiority depends on the situation. I have learned a lot from the mechanics where I've been working for the past few months. Copper is dominant in most situations. This is an industrial atmosphere, but piping for deionized water systems, additions to structures for DWV, etc. require plastic.
I have noticed the yin and yang balance between the two, where they both have strengths and weaknesses, more so than before.
Interesting how my perspective has changed.
 

mcintoshmc

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Ok, so I currently have a line running from my panel to a galvanized pipe, if I go plastic then I'll need a 10 in copper pipe. Will I need a few of those at different locations throughout the crawl space for my GFI receptacles?

Thanks for the help by the way. I realize this may be an electrical question on a plumbing site, but I really want to go with PEX, but I don't want to make the electrical job that much more expensive in the process.

Now, if you can tell me if its worth it to buy the PEX expansion tool from Milwaukee rather than going with the cheaper crimper tool, then that'll make my day...
 

Beni

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Ok, so I currently have a line running from my panel to a galvanized pipe, if I go plastic then I'll need a 10 in copper pipe. Will I need a few of those at different locations throughout the crawl space for my GFI receptacles?
If you have galvanized pipe running underground to a street or well then you don't need a ground rod. If your underground pipe is plastic then you will need to have a 10 foot long ground rod (not a pipe) installed near your panel and a ground wire run from the panel to the rod.
 

Beni

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I believe that there is a time and place for plastic as well as copper. Superiority depends on the situation. I have learned a lot from the mechanics where I've been working for the past few months. Copper is dominant in most situations. This is an industrial atmosphere, but piping for deionized water systems, additions to structures for DWV, etc. require plastic.
I have noticed the yin and yang balance between the two, where they both have strengths and weaknesses, more so than before.
Interesting how my perspective has changed.
Oh true no question there. But for typical residential piping, pex is pretty good.

Agreed that in heavy commercial and industrial use copper, PE, PB, 304 and 316 EP stainless as well other materials have their use. Gee I've had a 12" PVC water line enter a single building then transition to 12" stainless steel, then branch off to 10" down to 8" stainless and transition to 6" copper and below.

Really for DI, RO, USP pure water and WFI water, plastic or stainless steel is the only way to go. Stainless is used in Bio-tech/pharma for USP pure (RO/ DI/ UV) water and for WFI (water for injection) water where the piping must be sanitized to control bio contamination. WFI water is made from RO/DI water that is then run through a vapor compression still to make WFI water that is stored at 180 degrees F. to limit bacterial growth. Cool stuff.
 

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