Polybutylene piping is a type of plastic water supply piping that was installed in homes between the years 1978 through mid 1996. Recently, we found this piping in a home built in 1997. They were used because they offered flexibility and ease of installation. An entire house could be piped in a single day. So they were cheaper and faster to install than traditional copper piping. We have come across polybutylene piping in single family homes and multi-unit condominium communities alike. Often, communities were built by the same developer using the same contractors and when one home has the piping, there is a good chance they all do.
The problem with this type of piping is that it has a history of failure, causing major damage. They were installed using a crimping system which over time, started to leak. The documented failures mostly occurred at the connections, but has also failed along the piping as well. 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 have already occurred to the structure including mold damages.
Since almost all of a homes water pipes are run either underneath the house or in the attic then inside the walls, they're not always easy to find. One reason polybutylene piping is not readily apparent is because the piping is transitioned from the polybutylene to copper just behind the walls in 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 in the house is copper. Often, a homeowner is not even aware the house has polybutylene installed.
When we perform a home inspection, we look for certain signs and indicators that lead 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 gentle tug. If the piping is all copper, they will feel rigid and will not have too much play. If they are polybutylene, they will often 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 physically finding them in the attic, or if possible, inside the walls. We do this by using specialized tools such as a borescope. 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 or ASTM3309, among other wording. 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 and others may exclude water damage coverage. We recommend consulting with your insurance carrier to obtain definitive information regarding coverage. Insurance aspects aside, we must keep in mind that polybutylene has a history of failure and can fail at any time. Water pipes that fail behind walls will often cause water and mold damages before the homeowner realizes it and will result in having to remove sections of walls, floors and or ceilings in order to repair the leaks in addition to mold complications.
Once polybutylene is discovered, a homeowner must then decide the next course of action. It would be best to contact a reputable and qualified plumbing contractor for a consultation and quote for replacing the piping. We always recommend that a home with polybutylene should be completely retrofitted with new, modern piping.
The pictures below are actual photos taken of polybutylene piping we found in homes we inspected.
When piping is run from underneath the house, it can be difficult to access the piping behind walls but we use borescopes which help us confirm what kind of pipes are really installed in the home.
Here is a map with houses where we found polybutylene pipes in the year 2021.