Most modern plumbing today is made from copper pipes. This metal replaced galvanized steel as the material of choice for plumbing systems because of its light weight, greater flexibility, and most important of all, resistance to corrosion. Corrosion over time is one of the biggest drawbacks of galvanized steel and a reason that new materials were sought.
However, copper pipe can corrode in a specific way. It's called pitted corrosion and leads to the creation of pinhole leaks. This is an unfortunate problem that can affect the plumbing in many homes, and it needs remedy from professional plumbers. If your residential plumbing is experiencing any kind of leak, of any size, get on the phone to a licensed plumber right away to take care of it.
The saga of pinhole leaks
No one is currently certain of why pitted corrosion occurs in copper pipes. It may have a connection to chemical in the municipal water that comes from treatment plants, or perhaps from soil deposits. Another theory is that copper pipes are often used to ground electrical wiring, and the electrostatic charge causes the degradation leading to pitted corrosion.
Whatever the cause, pitted corrosion shows up as a small gray patch along the piping. It occurs in isolated spots, and it weakens the material enough that small amounts of water start to escape. Just drops... but it's enough to become a problem.
Any leak in your plumbing is a serious issue. It only takes a small amount of moisture buildup to start to eat through drywall and create mold and mildew. A pinhole leak is a major trouble that must be taken care of as soon as you notice signs that it is occurring (such as discolored spots on the walls or warping in floorboards).
Professional plumbers can handle sealing pinhole leaks that are causing problems. If you continue to experience pinhole leaking, such as three leaks within a 6 to 8-month period, you may wish to consider a whole-house repiping job. Consult with your plumber about your options.