PEX for a Water Main

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PlumbingSocal

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In my area (Southern California) most plumbing companies seem to run poly pipe for the water main. Why isn’t PEX A a more popular option?

From what I understand it needs to be sleeved, so does the foam insulation count?

Also, I know it needs to turn into copper prior to going through their build-up wall. Is it 15 feet worth that’s required for grounding?

Any feedback helps

PS - poly pipe is actually the same thing as PEX, The only difference is PEX is cross-linked making it more resilient. You would think it would be used more than standard poly pipe.

Is there something I’m missing?
 

Twowaxhack

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I think poly is cheaper.

I believe it’s minimum 20’ of copper for grounding.

I’m not sure though.
 

PlumbingSocal

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EDIT: I just got off the phone with Uponor, they said California is UPC and PEX doesn’t have awwa stamp it requires. Not approved for water service in CA.​

EDIT: turns out shark bite PEX is approved for underground burial for main waterlines (awwa) approve. Only downside is the shark bite PEX is the crimp version, I would not feel comfortable using those size reducing fittings on someone’s mainline.​

I see now why people use poly pipe!​
 
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FishScreener

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I think poly is cheaper.

I believe it’s minimum 20’ of copper for grounding.

I’m not sure though.
It is poor practice to connect the electrical and plumbing. There is a chance that a ground short can energize the plumbing, and kill people who touch fixtures. Preferred method is to install a Ufer ground in the foundation or slab, which bonds the ground to the reinforcing steel. Tiny bit more labor in the rebar, because you need to tie every crossing, instead of every fourth.

When I was in Vegas, where everything is slab on grade, they mounted the meter box, and breaker panel on steel C-channels, and then u-bolted the bottom of both channels to the reinforcing for the footings and slab. Once the slab was poured, the electricians, dropped out of the bottom of the panel to mount twelve 120-volt, and four 240-volt weather tight receptacles, and the power co connected the power. After dry in, they would run the house wiring, and after drywall and paint, they connected the household wiring, and removed all the receptacle below the panel, and connected those breakers to the receptacles in the garage, and the 240 to the water heater.
 

PlumbingSocal

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It is poor practice to connect the electrical and plumbing. There is a chance that a ground short can energize the plumbing, and kill people who touch fixtures. Preferred method is to install a Ufer ground in the foundation or slab, which bonds the ground to the reinforcing steel. Tiny bit more labor in the rebar, because you need to tie every crossing, instead of every fourth.

When I was in Vegas, where everything is slab on grade, they mounted the meter box, and breaker panel on steel C-channels, and then u-bolted the bottom of both channels to the reinforcing for the footings and slab. Once the slab was poured, the electricians, dropped out of the bottom of the panel to mount twelve 120-volt, and four 240-volt weather tight receptacles, and the power co connected the power. After dry in, they would run the house wiring, and after drywall and paint, they connected the household wiring, and removed all the receptacle below the panel, and connected those breakers to the receptacles in the garage, and the 240 to the water heater.
It might be poor practice but it’s code here in California. My requirements are that there is copper for a licensed electrician to ground to, the rest is up to California 🤷🏻‍♂️
 

PerplexedPlumber

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Whether or not it is accepted by code, I would not tie an electrical ground to a water line. Maybe you have few thunderstorms, but I was in a shower many years ago in an older home (at that time) when lightening struck, and can assure you that metal plumbing and tap water carry some charge. We use separate 8' deep grounding rods for electrical systems.
 

PlumbingSocal

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Whether or not it is accepted by code, I would not tie an electrical ground to a water line. Maybe you have few thunderstorms, but I was in a shower many years ago in an older home (at that time) when lightening struck, and can assure you that metal plumbing and tap water carry some charge. We use separate 8' deep grounding rods for electrical systems.
Sounds like the better way to do it, not sure why grounding on water lines became mainstream…
 

Twowaxhack

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It is poor practice to connect the electrical and plumbing. There is a chance that a ground short can energize the plumbing, and kill people who touch fixtures.
Sorry friend but it’s required by code here and you will not get your electrical service approved until it’s grounded to the copper plumbing if you have at least 20’+ of feet copper pipe in the ground.,

Now, you can disagree with that and that’s fine but note that many people disagree with your theory.
 

Twowaxhack

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Whether or not it is accepted by code, I would not tie an electrical ground to a water line. Maybe you have few thunderstorms, but I was in a shower many years ago in an older home (at that time) when lightening struck, and can assure you that metal plumbing and tap water carry some charge. We use separate 8' deep grounding rods for electrical systems.
We use ground rods too......the ground to the plumbing system is secondary.

The ground rod at the panel is the primary ground.

This is nothing new. It’s been done for years.

Stainless gas pipe, like trac pipe for example is also required to be grounded. It helps prevent holes being blown in it from lightning, although it’s not 100% effective.

Here is a couple pics from a copper pipe that had a ground clamp on it.

It was struck by lightning. It blew holes in the pipe. Nothing was damaged in the house.

It’s well known here that you don’t shower in a lightning storm. I’ve repaired many copper AND EVEN PVC that had lightning damage.

I’ve never heard of anyone being killed BECAUSE their electrical system was grounded to their copper plumbing, in fact it’s the opposite. The copper pipe is the path to ground.......

ED34FECC-EC68-4598-8E1D-A33E321325E1.pngECCECA17-5953-4A2F-BA22-6FFDB12B990B.png
 
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PerplexedPlumber

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You have a good history of images - would be good for compiling a book.

I tend to think in terms of single-family homes, and prefer PEX, bedded in fines, for supply. (PVC before that) Even our gas line is now a type of PEX. (previously copper) Metal corrosion, and this is a wetter area, is the main reason I prefer PEX. You make a clear point about grounding a metal supply line, but if I had to connect to a metal supply line, I would want to transition to PEX to go inside the house.

In my early 20s, that was not well-known to me, but it was a memorable lesson.
 

Twowaxhack

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Here is a good article with code references to read about grounding copper plumbing.

 

PlumbingSocal

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We use ground rods too......the ground to the plumbing system is secondary.

The ground rod at the panel is the primary ground.

This is nothing new. It’s been done for years.

Stainless gas pipe, like trac pipe for example is also required to be grounded. It helps prevent holes being blown in it from lightning, although it’s not 100% effective.

Here is a couple pics from a copper pipe that had a ground clamp on it.

It was struck by lightning. It blew holes in the pipe. Nothing was damaged in the house.

It’s well known here that you don’t shower in a lightning storm. I’ve repaired many copper AND EVEN PVC that had lightning damage.

I’ve never heard of anyone being killed BECAUSE their electrical system was grounded to their copper plumbing, in fact it’s the opposite. The copper pipe is the path to ground.......

View attachment 29473View attachment 29474
Crazy, had no idea what happened with lightning!
 

FishScreener

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The code requires that all grounds be bonded, and that you must have minimum of two grounds. So, if you have metal pipe, it needs to bonded to the ground loop. If you don’t have metal pipe, there is no requirement to install metal pipe to create a ground. The code currently requires that if you’re installing reinforced sub grade concrete the reinforcing steel be bonded to the ground loop. The grounds are: Metal Underground piping; Concrete encased electrodes (Ufer ground); Ground rings, which is a minimum 2-AWG bare copper wire at least of 20-ft in length, buried at lest 30-inches below the ground surface; Rod or pipe electrodes, with a minimum length of 8-ft, and corrosion resistant surface; and, listed plate electrodes.
 

Twowaxhack

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Crazy, had no idea what happened with lightning!
I’ve seen lightning blow pvc water pipe out of the ground.

Tear a bed in half

Blow a chunk of concrete the size of a basket ball off a foundation.

Weld appliances together.

Weld a bike to an iron railing.

Blow a hole in a gas and water line that was touching and water was pouring out of the gas meter.

Blow three of my friends father in laws toes off.

I live in one of the rainiest cities in the country and most of that rain comes from thunderstorms that produce ample amounts of lightning. The typical area gets 15 flashes of lightning per square mile per year. We get 30, double the national average.

Lightning does what it wants.
 
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PerplexedPlumber

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Fishscreener: the ground rods are for the electrical system and are required.

TwoWax: You definitely need to incorporate a chapter on lightening, with images. Lightening does some bizarre things, certainly. Long ago, it followed a path from the ground up a metal pipe in a well in one location and took out the pump switch and pump. It regularly blows limbs off trees or shatters trees, throwing pieces as far as 100' in a bad hit. It has killed several laptops, printers, routers, etc. here over the past 20 years, all on especially sensitive surge protectors. (The ones on battery backup systems have so far been OK.) Makes you wonder why we installed a metal roof. All of this, and you have more electrical storms than we do. So is that thing in the movie about lightening producing glass from beach sand a real thing there?
 

Mikieboyblue

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I know this post is a little old and forgive me for this but I always thought the copper pipe was bonded to the panel ground so that you couldn't get zapped by way of fixtures, not as a means to provide another ground. Here's why
...the pipe in my house from the well to the pressure tank is all PVC or some 1970s variant. The plumbing through the rest of the house is copper. The copper is bonded to the panel ground / neutral bar. There is a ground rod at the meter (no clue how deep). Since the copper doesn't actually touch the ground, there is no way it is acting as a ground. Right?

Further, I am replacing all the copper with PEX so there will no longer by a bond from the plumbing to the panel.

I'll add the short stance of CSST gas pipe extending iron pipe toba stove is bonded by #4 to the same grounding rod.
 

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