Polybutylene piping is a type of plastic water supply piping installed in homes between the years 1978 through mid 1996. They were used because they offered flexibility and ease of installation at a cheaper cost. A whole house could be piped in a single day. So they were cheaper and faster to install than traditional copper. But since almost all of a houses water pipes are run either underneath the house or in the attic then inside the walls, they're not so easy to find. One reason polybutylene piping is not readily apparent is because the pipes are transitioned from the plastic PB to copper when they get to the back of sinks, toilets, washers and water heaters. As a result, from the inside of the house, you only see copper. Thus thinking the piping is copper throughout.
The problem with this type of piping is mostly in their connections. They were connected using a crimping system which over time, has proven to fail and started to leak. The documented failures mostly occurred at these connections. And when leaks developed inside of the walls, they can leak for a long period of time before being noticed. By the time a homeowner notices the walls are wet, substantial damage can occur to the structure including mold growth.
When we perform a home inspection, we look for certain signs and indicators that allow us to suspect the presence of polybutylene piping. The first indicator is the year a home was built. Any home built between 1978 to mid 1996 can be a candidate. At the house, we test each water valve by giving them a tug. If the piping is all copper, they will feel rigid and will not have too much play. If they are polybutylene, they will feel much looser and have more wiggle to them. This is a big indicator. If we find the supply valves to have excessive "play" we will then try and confirm the presence of polybutylene by finding them in the attic, or if possible, inside the walls. We do this by using specialized tools such as a bore scope. An instrument that has a semi-rigid cable with a camera attached to the end. If we can find a point of entry adjacent to the valves, we can often get in far enough to capture this transition from copper to polybutylene. Once we find it, we capture it digitally. We also look in the attics and often times can find the piping there. Additonally, we use an infrared thermal camera to confirm they are still actively being used.
Polybutylene piping is most often a gray color and is stamped with the wording PB2110, among other wording. The PB2110 is confirmation. However, the visible presence is enough to state that a home has it installed. Polybutylene piping can and does affect homeowners insurance. Many insurance carriers consider them to be too big a risk and won't insure a home with polybutylene. Others may offer insurance at a higher rate.
Once polybutylene is found, a homeowner must then decide the next course of action. The options would be to leave them as they are, or opt to have the home re-piped. It would be best to contact a reputable and qualified plumbing contractor for a consultation and quote for replacing the piping.