According to Gary Slusser :
Their metal fittings may be.
Plastic plumbing (ie: all plastic irrigation systems) is a lot more forgiving of freezing than copper or iron because it stretches somewhat.
But, expecting it to stand up to a lot of freeze-thaw cycles is just asking for trouble. Which is why you drain irrigation systems for example.
According to Gary Slusser :
What Gary says is true, however, I'll point out that such problems are rare overall, corrosion mostly being a concern in some specific areas.
I've never heard even hinted that copper pipe can be a toxicity hazard to humans - copper is an essential mineral (in low concentrations of course) certainly nothing even remotely close to the issue with lead solder.
Further, copper is _much_ more toxic to lower life forms than mammals. Bare copper is rather more unlikely to harbor most bacteria than plastic is.
[There's a reason that PT lumber has copper in it...]
beat
aluminum or wood
This is Turtle.
I see you don't do much plumbing do you.
TURTLE
I've seen some copper joints with a greenish ick around them, sometimes culiminating in a 3-dimensional chunk of chalky ick. What is that?
Remains of the ick accumulation process. Better than at the base of the commode, IMO.
That ick comes from electroylisis, which in the plumbing world, happens when two different types of pipes come into contact with each other, and the results tend to show up at the joints, as you noticed. Most often happens when someone uses tin/galvanized hangers to tie the pipes to wood structure, or lays conduit right over the copper pipe without sticking a piece of wood shim or cardboard or hunk of foam or whatever to prevent direct contact between the two un-like pipes, or when someone replaces a section of copper pipe with galvanized without using a dilectric union, which is made of plastic, rubber and brass (brass doesn't react with other metals, which is why brass is used for pipe fittings).
AJS
"Chris Lewis" wrote
In any type of plumbing, if the tubing expands as the water freezes, the pressure is relieved, thereby the fittings don't break.
PE expands much more than other plastics, such as PVC, but PEX is able to expand (its ID) more than any other type of water plumbing material without failure. It has been tested to many thousands of expansions without failure. Some is expanded to make its connections as opposed to crimped connections. Heating it allows it to restore to its original shape, such as when a piece has been kinked. This is from tech sheets and installation guides. Where do you get your info from?
And as I said, the choice of the material for potable water lines should be dictated but the water quality and since plastics are totally inert.... what to use should be a no brainer... well for those that are aware of water quality and metal tubing problem issues anyway.
Gary Quality Water Associates
"Chris Lewis" wrote
"problems are rare overall"! Pinholes in copper tubing used for potable water line is a huge world wide problem. I've been reading about it and looking at maps of problem areas for years. I've also been treating water that causes the problem for 16 years now. And water isn't the only cause. Look at any acid rain problem area maps and you'll see some of the areas effected.
As far as copper toxicity to humans, every state of the US and province of Canada, along with European country has established the acceptable level of copper in potable water. In the US the EPA and state limits are measured in parts per Billion. They do that with lead and many other contaminates found in potable water that are proven and serious health problems in humans; especially the infirm and young children. Chris, are you pulling these opinions outta yer ear, where do you get your potable water quality issues information from?
Gary Quality Water Associates
It can be caused by soldering flux too, which if it is happening at a fitting, it's much more likely it's flux. Brass does too corrode, just more slowly.
Gary Quality Water Associates
This is Turtle.
It's what AJ said if it is all greenish but if you have white in it. It is a pin hole leak.
TURTLE
I guess I just had a pretty darn good instructor..
Polybutylene pipes don't burst when frozen.
RB
Edw>
IF it's the same money, go with copper. The only reaon why new houses use plastic is because it's cheaper to buy and install and the skill level used to install it is lower (i.e.- even a Mexican can do it).
According to TURTLE :
I do lots. I've also worked with copper pipe in a machine shop, and done other many non-plumbing things with copper.
I also have a home constructed by and for a plumber who thought that copper pipe was the answer to everything. TV mast, closet rods, driveway stakes, the works.
Got me a healthy respect for what copper is good for, and what it's not.
Makes lousy TV mast, driveway stakes or weaponry. There's a lot of crushed, torn, mushroomed and kinked copper pipe left behind by the original owner to prove it.
And one or two from my efforts.
How much dog bashing with copper pipe do you do anyway?
According to Gary Slusser :
My own plumbing...
I just had a short copper segment (about 3") on a PE line rupture (missed draining part of a irrigation line segment feeding a hose bib).
As long as the water stays liquid during expansion, then, of course plastic pipe expansion will prevent rigid metal connectors from rupturing.
But it doesn't stay liquid during expansion.
The expansion of water during freezing takes place from the minima volume (@4 degrees C) down and _during_ crystalization.
Much of the expansion therefore takes place while the water can't flow, because it's at least partially "locked in place". Whether it'll rupture the fitting depends on a lot of factors (ie: fitting length, freeze rate, line diameter, where in the pipe it starts freezing, etc). It won't necessarily rupture on the first cycle either (but it was the first season for the fitting I just mentioned :-(.
Freezing lines, any lines, no matter what they're made of should be avoided.
Plastic pipe installations will certainly perform _better_ than rigid metal pipe in the face of freezing. But repeated freeze cycling is to be avoided especially when there's highly rigid parts in the system (metal connectors and fittings, "device" housings - ie: pumps, whether metal or plastic).
Do you have a reference somewhere to the comment about "copper toxicity" in plumbing?
I should also point out that plastics aren't entirely inert, as the PB plumbing class lawsuit proved...
Don't get me wrong, I use plastic pipe whenever appropriate myself. But pros-cons aren't entirely one-sided.
According to Gary Slusser :
I get this for agreeing with you? Sheesh.
You may be taking my comments a little more overbroadly.
Yes, of course copper in high enough concentrations is toxic to just about everything.
My comment that may have _seemed_ to the contrary was merely to point out that copper toxicity varies widely through the plant and animal kingdom. Copper dosages that would kill some lifeforms won't touch others.
For example, copper is the active ingredient in many algaecides used in aquariums. Kills the algae, doesn't hurt the fish. Copper is _much_ more toxic to plants and invertibrates (ie: slugs and snails) than vertibrates (ie: fish, and us).
Hence the comment that copper is a toxic substrate for most bacteria. Ie: copper is _less_ likely to support (most types of) bacteria than plastic is in the same conditions.
Further, copper is also an "essential mineral". There are, for example, vitamin supplements for people that contain copper. Unlike lead, which is not.
Of course there are limits as to how much copper is permissible in potable water. There are limits to _everything_ in potable water, toxic or not.
I pride myself in keeping up to date in these sorts of issues. Lead solder, for example, has been a very big issue for a lot of years. The PB plumbing class action lawsuit, Al wiring, asbestos, UFFI, CCA etc.
But I don't remember hearing/seeing anything about copper contamination being a particularly significant concern in routine every day household plumbing.
Hence I ask you (for about the third time), do you have references for this being a significant issue for ordinary household plumbing?
_Not_ what the limits are. I've found those (including Canada's).
But where someone says that the copper pipe in your house alone (as opposed to the rest of the water system getting water to your house) is a significant concern. With some real facts to back them up.
Since you're a guy who keeps abreast of such things, I remember a few decades ago when PVC pipe started getting knocked because homeowners started replacing their copper pipes with it because it was so damn cheap, so they started using it for their faucet feeds, too. News at the time was this was bad for drinking water lines (but OK for waste lines) because PVC-borne chemicals leaching into the water over time. Not enough to cause someone to drop dead on the spot or anything, but perhaps significant over many years -- just like this argument thread related to copper pipe. Is there anything in your current science that suggests a similar concern for plastic pipe used now? I would imagine the plastics industry has come a ways since the 1970s and '80s and maybe addressed this, but what say you since you seem to follow it more closely than the average homeowner guy who doesn't worry about such things until some household disaster probably forces him to worry about it?
AJS
According to Gary Slusser :
Galvanic corrosion is always a possibility, but only where dissimilar metals touch.
On a straight copper fitting, it won't be galvanic.
Many corrosion products of copper are green (eg: chloride salts). IIRC, copper sulphides/sulphates are blue.
Most of the corrosion products of lead are white - that's why white paint used to be based on lead ....
Green suggests that it's most likely copper corroding in contact with something containing chlorine. Ie: salt (road or table) or plumbing flux.
On plumbing, it's probably flux. On automotive wiring, here it's usually road salt.
White can have a number of different causes, but they're mostly to do with water on the surface interacting with the solder. Whether it be pinhole leaks or condensation or whatever.
In particular, condensation on lead-based plumbing solder is probably the cause of most white powder deposits. But evaporation from a pinhole leak leaving water hardness "behind" as it evaporates is also a possibility (in many cases the crud buildup plugs the pinhole leak).
You can see that with objects made out of lead - subjected to long-term repeated dunkings or condensation, lead picks up a very soft whitish "fuzz".
According to AJScott :
I believe most of the issue with PVC pipe back then was that (a) most of it isn't rated for full plumbing pressures often seen, and (b) (still now) certainly _not_ for hot water under any pressure. So, not so much toxicity, , but I assume it's still approvedbut simple pipe bursts.
However,
Vinyl chloride (primary "input" to PVC manufacturing) is _very_ _very_ nastily toxic. And carcinogenic. etc. Big uproar over VC toxicity in manufacturing facilities, spills etc.
It's true that materials not intended for potable water usage do not have the same manufacturing/standards controls as materials intended for potable water.
Ie: a material not intended for potable water won't be as stringently controlled, and due to manufacturing differences may leach things you wouldn't dream of accepting in potable water.
Ie: some PVC may not be completely "P'd" (polymerized, as in assembled into inert/non-toxic long chain molecules). Ie: it may leach small quantities of VC.
You'd be crazy to use low-end cheapie PVC tubing for potable water, entirely aside from the point that it's really not pressure-rated even for cold water. Here, building code requires "CSA approved PVC tubing" (ie: for well pump lines), which is several notches above the regular irrigation tubing and is quite a bit more expensive.
PVC is not allowed in "regular" residential plumbing, period.
Also, as I understand it, PB pipe is sensitive to trace quantities of chlorine (and/or chlorides), and the pipe can suffer damage (including fail) from it. [This is in addition to some issues about defective installation/materials in the crimping rings].
Which is part of the class-action lawsuit against (I think it's) Shell.
Several plastic pipes have come up over the years: ABS, PVC, CPVC, PB, PE, PEX and I'm probably missing some.
Most municipalities are quite anal about exactly which one you're permitted to use for what. IIRC, our codes permit CPVC for cold water only, PEX is good for both cold and hot. PB is hard to find now, but I assume it's still approved.
Given the various scandals about PVC and PB, the industry (and standards and municipalities and building codes) have learned quite a bit, and if anything, are very anal about what they permit now.
As such, I'd be pretty trusting of modern PEX from a reputable supplier, as long as whomever is installing it doesn't cut corners and uses the proper tools.
I'm not too worried about chemical leachate from PEX, because polyethylene is one of the most innocuous of all plastics.
I should also point out that many plastics are susceptable to UV damage, so "in-sun" applications are a bad idea. Don't know about PEX specifically.
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