Copper drain pipe

It is true; 40 years is about the limit for copper used in drainage applications.

I suspect that sections most affected are those in contact with soapy water waste. Local water quality may also have a lot to do with corrosion rate.

If you have significant corrosion in one place, look for it everywhere.

There is no reason that the supply piping will be similarly affected; it may go another 100 years.

Jim

Copper buried in concrete for radiant heating may only last 40 years, the acid in the concrete eats it away.

Anything resting against or otherwise touching that pipe, externally? Such as other dissimilar metal; maybe a ferrous metal strap possibly rusted away or an other metal staple or nail, which might have caused corrosion? BTW understanding that you are talking about copper waste pipe

I think there may be way too many variables for even an educated homeowner to know why a given copper drain line failed. Maybe it was a problem with the alloy. Maybe there something in the water. Maybe someone poured something down the drain they shouldn't have., etc.

For what it's worth, I have 50 year old copper drain pipes that don't show the least sign of problems.

Local conditions do make a difference. Copper will "corrode" that is what makes that green color on exposed copper. That green stuff is much harder and resistant than the copper.

The definitive answer depends on the water in your area, what you add to the water before it goes in the drain and the quality of the pipe and installation.

Complete nonsense. Concrete is alkaline, not acid.

Concrete does not contain acid, it contains alkali from its lime base. Both can eat copper.

Ok Doug Miller , maybe its alkaline, but ive seen many buildings adandone the radiant heat embedded in concrete from leaks of copper pipe. So what is the reason for the failure.

Beats me. There could be many reasons. Maybe settling of the slabs over time stresses the pipes mechanically. Maybe the system water is corrosive. Could be all kinds of things.

But it isn't "acid in the concrete".

By saying that it's complete nonsense are you saying that copper buried in concrete doesn't present problems? If so, I can give you the physical addresses of about 15,000 nearby Levitt homes that were built in the 40's and 50's that would contradict that premise.

The concrete is alkaline, but the problem is more complicated than simple chemistry. Whether it's from galvanic reaction, faulty installation during construction or shifting/cracking slabs is open to debate. In any event, the copper fails. Ufer grounds - bare copper ground wires - are buried in concrete without problems that I'm aware of, but copper plumbing is another story.

No, I'm saying the notion of acid in concrete is nonsense.

Nothing at the location of the failure. Since the pipe was in the floor, it wasn't likely to have been hit by a nail/staple anytime since the home was built. And yes, all the waste pipe in this house is copper with the exception of many of the p-traps which are PVC.

Am now a bit concerned about the rest of the hidden copper waste pipe. The plumber said nothing else that he could see appeared to have any signs of weakness. I do know the previous owners tended to be Draino happy. Could these type of de-clogging liquids sitting in the drain cause the pipe to corrode? If so, for future reference what types of things should we avoid putting down the drain?

Thanks for all the help. Doug

Concrete does not eat or hurt copper.

Copper shrinking and growing in a restricted environment might rub a hole in itself.

Yes.

No. Acid in concrete???

sdb