Cross-linked polyethylene (PEX) tubing is an increasingly popular choice – cheaper than copper, faster to install and virtually free of fittings that can leak. But who cares if it’s also adding unwanted chemical compounds to the water?
Arlene DiMarino’s plumber is pushing PEX tubing, but her research turns up some disquieting information that the plastic might leach chemicals into her drinking water.
DiMarino’s delimma is the subject of this week’s Q&A Spotlight.
PEX appeared headed for approval in California, where environmental regulations are typically tough, until a lawsuit earlier this year got in the way. Among other things, the suit alleges PEX can contribute MTBE and a related chemical to drinking water.
But copper doesn’t get a free pass, either. Not only is it susceptible to pin-hole leaks from acidic water, but high levels of dissolved copper in water pose their own health risks.
What’s the right move?
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Having spent 25 years in the plastics industry, I can say without reservation that PEX is a very safe material to use in plumbing and would be my choice in new construction. PEX is cross linked polyethylene. Polyethylene is an extremely common plastic in use worldwide, is FDA approved for direct food contact and is used extensively in packaging for many food products from milk bottles to cereal, meat and cheese. PEX contains no BPA, no heavy metals and burns cleanly without creating toxic fumes like PVC and other chlorinated materials produce. The potential for low molecular weight fractions migrating out of the PEX and into the water, is extremely low. It has many benefits over copper both in installation and potential health issues.
I realize that GBC and related subject matter is hot right now. However, I think you are hurting the quality of the content of your magazine with ecophobic "Green" articles to drive the "Green" fad further.
Why not just sum up the whole article in a sentence, PEX tubing for potable water distribution . . . green enough!
For me it does not mean a lot that it is FDA approved or that it is used worldwide.
How many times have we as Consumers been the Guinea pig for some new and supposedly save Products,
only to find out later that they are not save.
The bigger risk I see with PEX is the massive amount of lines being run by plumbers who have in the past shown little regard for what they do to the structure they drill holes through.
I don't trust any plastic plumbing for more than five years after installation. Before I got into home repair I worked in the vending industry installing coffee machines and repairing them. Our company policy (SF bay area) was to plumb every thing in copper (even in San Jose where they have a high mineral content in the water, knowing that I would replace the line in 3 years). I have heard horror stories of companies plumbing with "the newest plastic pipe on the market" and every time in fails with in 5 to 10 years usually causing the business to go under. I have personally seen the effects of a plastic plumbed water cooler failure. A bottled water company plumbed plastic off of a copper line that I had installed and it split open over a 3 day weekend. When the school open on Tuesday(the location where I did the work)they had water shooting out of the pipe and 8 inches of water on the floor. They tried to blame my company however I pointed out that it was not our work that had failed. I always had the customer look at and inspect the copper work (and sign off on it on the contract). Needless to say the bottled water company had quarter of a million dollar damage suit on their hands. So when some tells me that plastic is the only way to go I ask them "how much money do you have in you budget to replace this thing in 5 to 10 years". It cost more in the short run but it sure does save on the headaches and insurance claims.
Rennaissance_Man, you mention "the newest plastic pipe on the market" but Pex has been around a long time (40yrs in Europe, 20 in the US market). Is it really logical to compare something with that kind of tenure in residential plumbing to "new plastics" used in vending machines? It would seem to me, with all the people who are either just unwilling to switch to new methods & or have a vested interest in keeping copper as the plumbing mainstay, that if pex really was unreliable there'd be better evidence available than a vague anecdote about "plastic piping" in vending machines.
Rennaissance_Man, you mention "the newest plastic pipe on the market" but Pex has been around a long time (40yrs in Europe, 20 in the US market). Is it really logical to compare something with that kind of tenure in residential plumbing to "new plastics" used in vending machines? It would seem to me, with all the people who are either just unwilling to switch to new methods & or have a vested interest in keeping copper as the plumbing mainstay, that if pex really was unreliable there'd be better evidence available than a vague anecdote about "plastic piping" in vending machines.
Please let me clarify my last posting. In side most (coffee)vending machines are plumbed with silicon tubing (not under pressure)or it is done in copper (pressure lines). This is done because the industry has of a very long history of plastic failure use in the machines. Even the silicon lines will deteriorate over a period of years because of the mineral content on the water and from the continual contact with boiling water as is passes through the tubing. What my first posting was trying to communicate is that I do not trust the external connections from the customer's source to the external fittings on the machines. I can see what you are saying that it has been around for 40 years and it seems to be a "successful" product. However, has any independent study on the effects of the continual exposure by hot water on the PEX when it is used for radiant floor heating, or connections from the water heater, other than the manufacture or the FDA? I would be interested in reading that study and maybe it will convert me.
It should be obvious, but it seems that everyone misses the point: The PEX revolution has nothing to do with the material!
Green? What's green about me having to drain a housefull of (cooled) water in the hot water lines before I have hot water at the tap? PEX avoids this with an entirely different piping arrangement, one where you need only replace the standing water in a single, tiny line. And what other plumbing method allows you to replace a bad line by tying the new to the old and 'fishing' it through?
Not sure who is writing this but PEX has been approved for use in all 50 states since 2009 and on a case by case basis since 2007. we've also been using PEX for plumbing remodels since 2001 in my part of California. Frankly I suspect the copper industry is behind these scare tactics. It seems every few years reports come up about rats eating the lines or some nonsense.
Municipalities all use plastic pipe to supply water to homes. Homes I lived in 50 years ago used poly pipe to supply water from the well to the house.
Copper may be more expensive than PEX; but as a homeowner who does his own plumbing work and works alone, I'll stick to copper for its ease of installation.
I've done my share of wrestling with polyethylene irrigation pipe that is thinner than PEX, and I've tangled with plenty of Romex on my own too. None of it is fun when working solo.
I'm not saying PEX is bad and I can see its advantages; but one needs to weigh the pros and cons of the materials.
At least we no longer use galvanized steel pipe for potable water.
In my personal opinion, I would rather prioritise my health in opposed to saving some money. Since PEX plumbing has said to inflict chemicals onto the drinking water, why should we risk that fact just so we could save some costs as PEX is cheaper and easier to install as compared to copper. Even though the percentage of the chemicals is low, but who knows what it might impose to our health in the long run?
I recently purchased a house that is built on a slab. The builder used PEX tubing and ran the system in the attic. The cold water line gets hot on sunny days causing me to have to purge the line of hot water to get cold water. I finally got a system with hw circ system but now I have been defeated again by having to purge the cold water lines. My brother in law( an experienced plumber ) says this comes with the territory when using PEX and not running the lines in the slab. Does anyone know of a solution to this problem ? Trying to save water in this drought can be trying.
JD
it really made us feel we were giving something back at this time of global crisis.
I restored an old house is southern New Mexico using PEX tubing. Thought is was great, "until" the mice started eating it. A real disaster. Any way to stop them?
amazing comments for knowledge i like it.