Between the years of 1978 and 1995, a form of plastic resin was used in piping of plumbing systems. This resin is called Polybutylene. Because the plastic resin was relatively inexpensive and easy to install, polybutylene was once deemed “the pipe of the future.”
This type of piping is most common in states like Arizona, Florida, southern Nevada and California as well as Texas, Alabama and Georgia. These states saw an increase in residential construction during the height of use of polybutylene. It is believed that this form of piping was installed in at least 6 million (and as many as 10 million) homes during this time frame for both internal and external piping in homes.
If “Poly” was used in the exterior water supply of a home, it will likely be blue but can also be gray or black. The piping typically enters the home through the basement wall or floor, or the crawlspace. Homeowners can find the main shutoff valve for the system at the end of the water main inside the home. Where the water main connects to the city’s water can also be a key indicator for this piping because in some instances, the piping was replaced in the home, but not throughout the exterior.
If the piping was used inside of your home, it can be found by the water heater, in the ceiling of the basement and will feed into the home’s sinks and toilets. It’s important to note that some plumbers commonly used what are called copper “stub outs” if the piping came out of the wall. However, poly piping might exist behind the walls.
Many professionals believe that certain elements in the water supply including chlorine, can react with the material used for the piping causing them to become brittle and micro-fractures can occur. If these fractures exist within the plumbing system, the entire system is no longer as strong and may fail without warning.
A few years after the piping began to be installed in homes, lawsuits were being filed claiming the material was defective and caused hundreds of millions of dollars in damages throughout homes. Manufacturers never admitted Polybutylene was defective, but they did settle for $950 million dollars.