water pipe material

[DaveLevenson]

My building is approaching 60 years old. In the past few years, I have had several leaks. The first of these was noticed by Howard when he and I visited the store I now own, back in 2005 when I was considering making an offer for it. That one was buried in the concrete floor. The seller bypassed the leaking pipe and had a new one run through the ceiling before we closed.

Another occurred in the incoming water line from the street, under the floor. My landlord had the floor broken up and hired a plumber to dig down to the pipe and replace a section. I watched him wrap the new copper with plastic as Mike described, before new concrete was poured. The township also got involved, as they had to shut the water off at the street. Their valve failed to close, so they dug a pit and replaced the valve with the main pressure on -- with the aid of a huge vacuum machine.

Since I have owned this store, there have been three more indoor leaks, right through the wall of 1.25" copper pipe. In each case, I have replaced the leaking section. When I examined the removed section, I found that the wall of the pipe had been eroded from the inside until the wall looked more like copper foil. These leaks have all been in the cold pipe between the service entrance and the tee that feeds the water heater. My sister-in-law who is a plumber tells me that this indicates that the pipe ends were not reamed properly when the system was assembled. She explains that leaving rough-cut ends causes a turbulent water flow which accelerates erosion.

[MrMachine]

Originally Posted by DaveLevenson

My building is approaching 60 years old. In the past few years, I have had several leaks. The first of these was noticed by Howard when he and I visited the store I now own, back in 2005 when I was considering making an offer for it. That one was buried in the concrete floor. The seller bypassed the leaking pipe and had a new one run through the ceiling before we closed.

Another occurred in the incoming water line from the street, under the floor. My landlord had the floor broken up and hired a plumber to dig down to the pipe and replace a section. I watched him wrap the new copper with plastic as Mike described, before new concrete was poured. The township also got involved, as they had to shut the water off at the street. Their valve failed to close, so they dug a pit and replaced the valve with the main pressure on -- with the aid of a huge vacuum machine.

Since I have owned this store, there have been three more indoor leaks, right through the wall of 1.25" copper pipe. In each case, I have replaced the leaking section. When I examined the removed section, I found that the wall of the pipe had been eroded from the inside until the wall looked more like copper foil. These leaks have all been in the cold pipe between the service entrance and the tee that feeds the water heater. My sister-in-law who is a plumber tells me that this indicates that the pipe ends were not reamed properly when the system was assembled. She explains that leaving rough-cut ends causes a turbulent water flow which accelerates erosion.

Now that makes a lot of sense!

[ldm]

Originally Posted by DaveLevenson

My building is approaching 60 years old. In the past few years, I have had several leaks. The first of these was noticed by Howard when he and I visited the store I now own, back in 2005 when I was considering making an offer for it. That one was buried in the concrete floor. The seller bypassed the leaking pipe and had a new one run through the ceiling before we closed.

Another occurred in the incoming water line from the street, under the floor. My landlord had the floor broken up and hired a plumber to dig down to the pipe and replace a section. I watched him wrap the new copper with plastic as Mike described, before new concrete was poured. The township also got involved, as they had to shut the water off at the street. Their valve failed to close, so they dug a pit and replaced the valve with the main pressure on -- with the aid of a huge vacuum machine.

Since I have owned this store, there have been three more indoor leaks, right through the wall of 1.25" copper pipe. In each case, I have replaced the leaking section. When I examined the removed section, I found that the wall of the pipe had been eroded from the inside until the wall looked more like copper foil. These leaks have all been in the cold pipe between the service entrance and the tee that feeds the water heater. My sister-in-law who is a plumber tells me that this indicates that the pipe ends were not reamed properly when the system was assembled. She explains that leaving rough-cut ends causes a turbulent water flow which accelerates erosion.

Dave: The problem you have sounds more like electrolysis between two dissimilar metals...maybe a steel flange v. a bronze on a circulating pump, a switch in materials without a proper dialectric union, etc. You would have to use a real dull cutting wheel to flare smaller copper lines out much past the fitting shoulders, and the thinner metal that flares has a tendency to wear away from the force of the water before it causes much trouble. That's been my experience anyway. Les

[ldm]

Originally Posted by Adamski

Mike,

Some laundromats used transparent hose for the drains on their extractors (not washers) decades ago. It was a marketing tool for those high-extract spinners.

Getting back to Suzy's original topic:
I guess I'd recommend that she simply fix the leaks in her copper pipe rather than change to a different system. This assumes that most of her piping is quite solid. My building is over 50 years old now. We've had a few leaks in the original copper pipe (always the underground pipe) but when cutting out the leaking section, we found the pipe on either end of the cut to be solid. One leak was under the floor in a tee for an old branch line that was already abandoned. It was capped but there was still pressure on it.

I've found that the leaks were always in the hot water lines rather than the cold water lines. I'm not sure why that is. All things considered, I'm quite satisfied with my copper plumbing though.

Larry: The majority of the leaks in underground copper piping are on the hot water side due to expansion and contraction. The pipe will rub against a rock, overpoured concrete, rebar, etc. If the systems were put in perfectly...which few are, this problem would not be prevelant on the hot side. Les

[Howard]

Dave:

That is the problem with trades people - they come up with some very strange "facts" as to why things take place. There will be a heck of a lot less turbulence caused by a few burs in a pipe than by a 90 degree elbow. And this disturbance will disappear a few pipe diameters downstream. I would bet it has to do with stray electrical currents or minerals in the water.

[mjwalsh]

Just thinking outloud here ,,,, but it seems like some city water supplies have a lower pH than others which seems could also be a factor affecting longevity of the copper.

Not sure .... it seems like on our softened water piping ... it may be the reason why we are getting by without working the handles on the 1.5" & above ball valves like Larry suggested every year or so.

mike