Hot Topics: Replacing Leaky Copper Pipes

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Original Post: leaky pipes in attic crawl space

Bluebellabodi Member

Our 60-year-old one-story slab foundation house has the hot and cold water pipes running through the attic crawl space. Last October, one sprung a tiny leak. Of course, by the time we noticed it, it had dripped through the ceiling and damaged the Sheetrock. Insurance paid for the whole check for mold and asbestos, and water damage restoration. They paid for the Sheetrock repair and painting. A large section of the pipe that leaked was changed out.

Tonight, about five months later, another part of our ceiling completely crashed down because of another water pipe leak in a different location—a tiny hole that obviously had been leaking for months. I am getting a little nervous; are our pipes going to spring a leak every few months? Should I have every readily accessible pipe in the attic crawl space replaced? They are copper pipes. No idea how old they are.

marksr Forum Topic Moderator

It sounds like new piping would be a good idea. At a bare minimum, I'd get in the habit of going into the attic every few weeks to check on things. It takes a good bit of water to damage the drywall enough for it to fall.

beelzebob Member

Copper pipe walls don't thin measurably in normal use during the lifetime of homes. Leaks develop from manufacturing defects, not thinning walls. If I were going to replace the pipe in the attic, I would use Type M copper or PEX. Also, there are many water leak monitors (accumulated water completes an electrical circuit) that can alert you to accumulating water or even closing a valve on the water line. To capture the water from a leak, I would place lengths of two- or three-inch DWV over the copper pipe (slotted for pipe diameter) so the leaking water has to drip out the bottom. I would place plastic pans under the DWV pipe to catch the water. I would also place a leak monitor in each pan and connect them to one alarm control.

XSleeper Group Moderator

Copper can be thinned by galvanic corrosion, by turbulence, and by minerals in the water that act as abrasives. There is much written on this subject.

There is often no rhyme or reason as to when or where it might occur. It's hard to say what your best course of action should be. Total replacement seems like overkill, but it probably is the only way to "guarantee" this doesn't continue to occur.

That being said, I replaced some copper (maybe four feet or so) for a friend where some elbows and pipe had sprung pinhole leaks. The house was about 40 years old at the time. A few months later, a few more showed up. Since then—nothing. It's been 15 years or more since then, and no problems with any of the rest of the pipes in the entire house.

zoesdad Member

If you are on well water and you have very acidic water, that can cause pinhole leaks. I’m on well water and my pipes (copper) were being eroded from very acidic water (pH=5.5), although I didn’t experience pinhole leaks, but the pipes were thinning.

If you are on well water, I would get it tested. You could add an acid neutralizing filter (I did) and it will stop the erosion. But if you are on municipal water instead, then acidic water wouldn’t be your problem.

Pilot Dane Group Moderator

I have to disagree. Where I live, copper pipes are a big problem. The water chemistry dissolves/erodes copper over time, thinning the pipes from the inside out. Eventually leaks start becoming more and more frequent. The only solution is to replace all the plumbing since the water is attacking all the copper piping in the house. This is generally easy to spot by any decent plumber as the metal in the pipes can become paper-thin.

Another possibility is that you are simply having bad luck and it's just a semi-random leak. Fixing that leak might keep things good for a long time.

Then, there is yet another situation where copper pipes can be eroded from the inside by installation errors such as not deburring the cut ends of the pipe and the flux used when soldering the pipes. Unfortunately, these situations can affect the whole house and replacing all the piping might be the best solution. When replacing any piping, my choice is PEX. It's not affected by water chemistry, is easy to install, and is highly resistant to damage from freezing.

Viriliter_Agite Member

Another vote for a PEX upgrade. You'll never feel right fixing the ceiling and wondering when the next leak will occur.

Bluebellabodhi Member

Thanks, everyone. All good advice, even though (of course) some of it is contradictory. I like the water leak monitor. I have to find out more about that.

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