Hot Topics: Is PEX Pipe Safe?

PEX and PVC pipes.

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Original Post: Paranoid now about PEX pipe install?

Brian1900 Member

I need to have some copper water pipe replaced in the basement due to some pinhole leaks. The house was built in 1971, so the copper I assume is from around then. I've been reading all these things about how PEX may have chemicals that can leach into the water. I was told by a plumber that I should use PEX since it's cheaper and quicker to put in, etc. What should I do? Copper or PEX?

Is it best to just filter at the tap and not worry about it? I'm a paranoid type, I guess.

Audioslave22 Member

Your water mains are plastic.

Gunguy45 Super Moderator

Mains are not always plastic. In fact, that would probably be a very small minority.

Don't worry about the PEX. You ARE being very paranoid. Copper (especially old soldered copper) is more likely to release more stuff into the water. PEX is very inert under almost any water condition. It may cause some smell and taste issues, especially when new, but those should fade with use and could likely be rectified with a simple activated charcoal filter, either tap mounted or via pitcher.

I bet I can find waaaay more articles about steak being bad for me than you found about PEX. Am I going to stop eating steak? No way!

Marq1 Member

Cheaper and faster do not always mean better. Personally, copper is at the top of my short list for water systems. A follow-up question: why are you seeing leaks? Is there a water quality issue?

joecaption Member

I've been using PEX ever since it came out and never had an issue. I can not think of a single good reason to use copper or CPVC anymore. When you have those old copper pipes removed and see what's inside, you'll be amazed and soon forget those false posts about PEX.

Zorfdt Forum Topic Moderator

If you read the internet long enough, you'll find examples of how everything in life is out to kill you. I wouldn't give another thought to plastic pipe. It's been safely in use for years and is where all commercial, residential, and supply piping is going.

Marq1 Member

To each their own, but I would never, ever, use plastic in a house I build for my clients or myself. As noted, it may be cheaper and easier (for somebody), but that is not always the right way!

Brian1900 Member

The leaks are some pinholes on the cold water lines, I was told. They're from 1971 I assume, so maybe they're just getting old? The majority look good to me, though. It's a small house, so there's not a lot of piping, save for the ones going to the baseboard heaters and those all look clean from what I can see.

minimac Member

The copper used was most likely the wrong type. It should have been type L, but many builders cheat and use thinner (and cheaper) type M. The pinholes are caused by water turbulence created when the pipe is not properly reamed after making cuts. If you insist on using PEX because it's faster and easier, realize also that it cannot be sterilized, although if you're on a municipal water system, it already contains a lot of chlorine. What you'll save on pipe, you'll spend on fittings and hangers (which are only as good as the installer), and should something happen like a nail or screw pierce it, it's not easily repaired. From my perspective, you could really save a lot by just using a garden hose for your water line.

Tolyn Ironhand Group Moderator

On a side note, the copper has been leaching into the water for years. How do you think the pipes have eroded?

Sidny Member

A lot of areas have acid water. I had to put in a chemical feeder and a water softener to correct my problem. I still have copper. Maybe it will keep the Legionaires' disease away.

Brian1900 Member

I'm on city water also, here in Maine.

guy48065 Member

Sterilizing potable water pipes? Legionaires' disease in closed pipes? Copper leaching? Unsafe city water (think Flint, MI)? Type L for low pressure drinking water supplies? You've all got ME paranoid, now!

Brian1900 Member

Had a plumber over today and he said, "If it were me, I'd just replace the section that is leaking. Copper pipe lasts for 60 years and the rest looks good." He wants $250 to replace about five feet. He said it's a FLAT RATE.

He said he wouldn't replace the whole pipe if it's not leaking. He looks to be very young, as was the last plumber this company sent. I'd say he's mid 20's.

guy48065 Member

For $250, the kid will use the pipe cutter in his pocket to cut the copper, a box knife to cut the PEX he has on the truck, and two Sharkbite connectors. 10 minutes later he'll be on the road looking for his next victim...err...customer.

zoesdad Member

IMHO $250 isn’t all that bad, even thought a 5’ pipe is only about $15 and the few couplings are cheap. But I wouldn’t let him use SharkBites. Make sure he solders.

I would check out the wall thickness and condition of the pipe that he cuts out. That might give you some idea of the condition of the rest of the copper piping. Mine is 50 years old and still working fine. If the water isn’t corrosive (and municipal water shouldn’t be) copper is known to last even up to 80 years.

Type (i.e., M, L, or K) came up in a previous post. I think many localities require L. M is too thin. I’d make sure he installs L.

Brian1900 Member

He said they use type L. This is a big chain company that does plumbing and heating. I told him I wanted copper, not PEX, although he said he did his whole house in PEX and tore out all his copper. I don't know if he's going to try and use SharkBites. Why specifically are they bad to use? Should I insist that he solders?

zoesdad Member

Why tear out perfectly good copper unless you are springing leaks all over the place? Maybe it just makes people feel more secure in that they won’t get a surprise leak someday, or maybe he already knew his pipes were in pretty bad shape—or maybe he is setting you up to get you to do a total PEX conversion.

I don’t think it’s real common, but I think there are in fact cases where the PEX connections leak because it wasn’t installed properly. That just doesn’t seem to happen with copper soldered connections.

I have used SharkBites, but I'm no expert. They work fine, but a soldered connection has a long history of being a good leak-free connection that is not going to change or deteriorate. Maybe the other guys will weigh in, but I bet he will just solder in the new pipe. I'm pretty sure that's the norm.

minimac Member

A lot of areas require that this sort of work is done by a licensed plumber and that it is inspected. Yeah, I know that seems dumb, but the reasoning is that you are connecting into a municipal system and even though L copper is spec'd for residential waterlines, most home builders use M (and get away with it) if they even use copper.

The copper leaching isn't an issue. The concern with sweated joints was the paranoia surrounding lead poisoning and the lead content that was in the 50-50 solder being used. The solder that's used now isn't an issue.

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