Old Type M Copper - Time to Repipe?

[MOB19]

I'm in process of replacing the carpet on the second floor of my house with hardwood. After pulling all of the carpet up, I can see where previous owner replaced the original galvanized pipe with type M copper.

I don't know how old the copper is from the repipe, but it isn't new. I've only been in the house for 3 years, and last year, I already had one pin hole leak.

Any suggestions if it's time to repipe, and if so, what material -- PEX or type L. It seems like a now or never situation since I can access all pipe runs.

 

[Jadnashua]

Were the pinholes just downstream of a fitting? The reason I ask is that some don't reform the cut end of a copper pipe prior to installing the fitting. The deformation caused by using a typical tubing cutter (it's worse if the cutter is dull) will create a lip on the pipe end. If you do not ream that back into a nice shape without the lip, the turbulence caused by the water when it flows can literally cause pinhole leaks. They tend to happen in a series after the fitting, downstream. The use of a hot water recirculation system, especially if the pump is oversized, can cause degradation faster. Having pipes that are undersized causes the water velocity to exceed recommendations, and that can shorten the life of the pipes, especially on hot lines.

Some people have water that is more reactive than others, which may mean copper doesn't last all that long. Also, if in contact with the soil, some soils will corrode copper. It's also possible that there was a defective section. Another possibility is the use of (excessive) acidic flux that wasn't cleaned off.

So, it's hard to say. The copper in the house I grew up in is over 60-years old, and is still functioning without issues. There are advantages and disadvantages for either type...depends on your priorities and local water conditions.

 

[Sponsor]

 

[Plumber69]

we call that red copper here. 10% of houses here were plumbed with that to save a few hundred bucks. Its evil here

 

[Jadnashua]

WEll, M is definitely thinner, but not necessarily bad stuff.

 

[MOB19]

It certainly is the old red copper, with red writing showing it was manufactured in Mexico. Unfortunately it doesn't have a date of manufacture.

The pin hole occurred at a branch off of the 3/4" supply. It was in a 1/2" line, downstream of a 1/2" tee reducer and a couple of elbows. I think it was the hot line. I don't have hot water recirculating pump.

Would it at least make sense to replace the lines in the floor, up to wall connections? At least that way I don't have to worry about leaking under the floor and I don't have to live through a drywall mess some of the final runs in the more challenging locations.

I'm going to get some quotes and see what they say and their suggestions on PEX vs copper. It just won't be easier than it is right now, with the floors open and pipes accessible, and I can't bear to think of ruining new flooring a year or two from now.

 

[Jadnashua]

Pex has some advantages, mostly in that it is easier to install and because it is so flexible, you can avoid using most fittings except at the beginning and the end. But, the ID is smaller than the equivalent copper, and the fittings reduce it more (especially if you use the crimp style versus the expansion type). So, if the line is 1/2" copper, you might want to consider 3/4" pex...it's bigger than the 1/2" copper, and smaller than 3/4" copper. 1/2" pex to an individual fixture should be fine unless it is a large tub or a hose bib where you want maximum flow. Most other fixtures are flow restricted and can't use the full volume (unless there's a bunch of items on that line and you want to run them at the same time).

If it will make you feel better, swap out what's easy now. Be sure to save the old copper and take it to a recycling center...it has a fairly significant value. Be prepared with some ID which they usually ask for to help ensure you didn't steal it out of a house. If you cut off the fittings into a separate pile, the bare copper pipe without soldered connections has a higher value than mixed with fittings and solder. If you do that, they'll weigh and price each bundle separately.

 

[Sylvan]

I never used Type m Or DWV . Even for heating I use Type L (hydroponics) and type K for underground

The reason copper does fail is the human factor in many cases

1- Excessive velocity (as mentioned)

2- Tubing not reamed also as mentioned

3- Self cleaning fluxes not properly removed (flushed)

4- Imported crap such as the black steel imported from Korea and had major failures

5- Water PH not tested

 

[MOB19]

The copper will be replaced with week.

In a case of "since I'm there," I am replacing a leaking shower faucet at the same time since I have to open the drywall up behind the shower. (I and two plumbers have looked at the faucet cannot tell which brand it is. They think it's a cheap knock-off, so I want to replace it with Hansgrohe.)

Hansgrohe uses the IBox rough valve which needs a 4-3/4" hole. Whats the best way to create the hole in the wall? I see two options, a multi-tool with diamond grit blade or a 4-3/4" diamond grit hole saw. For a hole saw I could make a jig to center it correctly.

Pictures of the current wall and with a 4-3/4" template around the hole are attached.

 

[Jadnashua]

A hole saw would be the neatest, but all you may need to do is to cut out the cement board so the opening is a bit larger...it would depend on the valve body. To cut that, you just need to score it and snap. A heavy duty pair of pliers should be able to deal with it.

Note, there's a min/max for the mounting depth. You should mock up the valve with your trim to see how you best prefer the look. All the min/max does is tell you if it will fit, not that you'll like how it looks. the plaster guard isn't particularly important if the wall is tiled already...it's useful prior to installing the tile or if there's what is called a thin-wall install, which you don't have.

You need a large enough hole to actually mount the trim and gain access to the body to replace the guts when they fail...that may not need that whole large diameter.

You can cut the hole with a diamond wheel on a grinder, but it takes a bit of finesse.