Why do gray pipes leak?The truth is that all piping can and will leak eventually. However if you have gray piping in your home, get ready for a problem.
This grey or black piping put into homes in the boom times of the 70's and 80's is now responsible for the majority of plumbing leaks
I believe the problem is two fold.
- The chemical problem with the pipe reacting to continued chlorine and other natural occurring chemicals against the walls of the plastic tubing. This plastic is oil based and the oil is leaching out of the piping making the pipes brittle.
- Plastic fittings - The piping was designed to expand without bursting, then return to its original shape. A problem I see is that the piping would always return to its shape if bent as well. During the installation, plumbers would often bend the pipes to avoid fittings and there would be stress remaining in the bending. This pent-up stress would remain there over the years and the plastic fittings would break after years of this stress. Even today when the piping does break, the bent pipes will return to straight.
Unfortunately, there is not much you can do besides replacing the pipes in the home. Usually with PEX piping being the best affordable option.