copper better than Pex for underground?

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Rich39

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I've been reading conflicting advice on this. Yes, I know that Pex can expand if the pipe freezes - but freezing of the Water Supply Pipe to the home has never been a problem even at 10 degrees below zero. I'm thinking that copper is more resistant to degradation. How long has Pex been in widespread use for underground residential water suppy? I'm in PA.

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skeezix

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I'd like to know too. Seven years ago the copper water inlet line from the meter to the house was replaced with PEX, and I'm wondering how long that will last.
 

havasu

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We have a newer residential tract, with 1200 homes, which was built in 2005, all with PEX plumbing, that have filed a class action lawsuit against the builder due to several PEX leaks at every home in the tract. I'm trying to ask exactly what is failing, but they all say it is within the connectors. Most are just replacing with good old copper, at the tune of $15K a piece.
 

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tailgunner

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Zurn was the brand the builder used. I did basement bath, kitchen and laundry tub plumbing and used Nibco.
 

arctic bill

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If you live in the north country and you have a plastic pex pipe
1) if the water service pipe freezes and it is copper you just pass low voltage dc through it to thaw it. with plastic you are screwed .
2) I have found a few cases that rats ate thought plastic pipe.
 

Mark.S

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Could be they just did a poor job installing the PEX and there is nothing intrinsically wrong with the components. No way to say from the information provided. There is a known issue with brass couplings leaching zinc, lead, and copper into the water. See the conclusion in this study:


but that doesn't say that it led to any leaks, just water contamination.
I've read that poor installation is most often the cause. Same with Sharkbite fittings. There are various youtube videos on the subject of complications of the various PEX connection types and how to avoid them. I think the manufacturer often gets blamed for poor workmanship during the install.
 

Mark.S

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If you live in the north country and you have a plastic pex pipe
1) if the water service pipe freezes and it is copper you just pass low voltage dc through it to thaw it. with plastic you are screwed .
2) I have found a few cases that rats ate thought plastic pipe.
Rats also like copper products hence chewing electrical wiring
 

RS

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My father put regular old black poly in the ground in the early 1950's on the farm that I grew up on, and it's still being used and just fine! Doesn't anyone use that anymore? It's available in up to 160 psi. A friend of ours has an outdoor wood furnace and last winter the hot line leading to the house started leaking, it had become very brittle, but I think it was 20 years old.
 

arctic bill

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My father put regular old black poly in the ground in the early 1950's on the farm that I grew up on, and it's still being used and just fine! Doesn't anyone use that anymore? It's available in up to 160 psi. A friend of ours has an outdoor wood furnace and last winter the hot line leading to the house started leaking, it had become very brittle, but I think it was 20 years old.
I have black poly at my cottage and i do like it,
but if you have to put a pipe 6 or more feet in the ground the cost of excavation is ten time the cost of the material, so why would you cheap out
 

RS

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We put the black poly 8 feet in the ground, and it lasted 65 years, it's obviously better than some of the new junk people are using.
 

Twowaxhack

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We put the black poly 8 feet in the ground, and it lasted 65 years, it's obviously better than some of the new junk people are using.
Please don’t take this the wrong way but......I’d have to see that to believe it.

Homeowners regularly telling me things they “ know “ that turn out to be incorrect.
 

Twowaxhack

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I found some leaking durapex in a lady’s house last week and she said that pipe was installed after the copper failed under the slab 7-8 yrs ago.

The pipe had the date stamped on it. Made in. 1998.

So 23 yrs ago......she claimed it was 7-8

I’d say 90% of the time the initial info I get from homeowners or family members are wrong. So wrong I almost don’t even listen to them any longer.
They’ll have you on a wild goose chase, swearing the entire time they’re right and some will continue to argue even when you’ve proved them wrong.
 

arctic bill

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I remember many years ago we started to use copper for in floor heating, as 2waxhack said it took 25 years to eat though. copper is great but not in concrete or acidic soil .
 

Mark.S

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I experienced a slab leak in a (copper) hot water pipe under the tile floor in the kitchen of my last (1980s era) house....not fun
 

Twowaxhack

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It all leaks. I promise you it all leaks eventually. That’s how I make my money.

For the money, quality pex is the best option most of the time.

If money isn’t an object and the water is not acid then copper is the longer lasting material IMO

There are a lot of variables so each situation must be evaluated independently.
 
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