Between 1978 and 1995 water supply piping manufacturers widely utilized a form of plastic resin called Polybutylene. 


The material was inexpensive and easy to install and quickly became considered “the pipe of the future,” replacing traditional copper piping. 


It is estimated that about one in every four or five homes built during the piping’s popularity have either underground water mains or interior water distribution piping containing Polybutylene in them.  While it was most typical in the “sun belt,” homes in the Mid Atlantic and Northwest Pacific States are amongst the approximated 6 to 10 million with the piping.


The major downfall of Polybutylene piping is that it has shown to negatively react with chlorine and other oxidants in public water supplies.  The pipes scale and flake and eventually become too brittle to be effective.


How to Know if You Have Poly Piping in Your Home


Blue is the most common color of Polybutylene underground water mains but they may also be black or gray.  These pipes are typically found entering a home somewhere near the water heater either in the basement wall or coming up through the floor.  The shut off valve is attached to the water mains end.  You should also check for Polybutylene piping coming off the water meter on the exterior of the home.  It can also be found running through the ceiling of an unfinished basement to feed toilets, sinks, and other fixtures.  You should check all areas where piping is present because some plumbers used a combination of copper and poly piping for different reasons during installation.


The manufacturers of Polybutylene piping have agreed to fund a $950 million class action settlement for the replacement of the piping as well as damage caused by it.  The manufacturers themselves have never admitted that Polybutylene is defective and evidence has shown that several factors contribute to the failure of the piping systems.  Installation issues have also been cited as a cause but there is no way to prove one way or the other.