What Are Polybutylene Pipes and Why Are They a Problem?
Nov 23, 2021
Polybutylene pipe was manufactured from the late 1970s to the mid-1990s by Shell Oil. It was a plastic, flexible pipe that was used for building new homes, mostly in the southern United States. The pipes began to have issues with leaks in the ’90s, leading Shell to cease production in 1995. A class-action lawsuit filed in 1996 awarded over $1 billion to plaintiffs to cover the cost to re-pipe more than 320,000 homes.
There are still homes with polybutylene piping systems in them, so homebuyers and homeowners alike should know about the existence of this pipe given its tendency to cause leaks and water damage. Read on to learn how to identify polybutylene and how to replace it.
What is polybutylene pipe?
Polybutylene, or PB, is a plastic resin manufactured by Shell Oil between the late 1970s and the mid-1990s. It was touted as innovative piping material thanks to its flexibility, heat and freeze resistance, and the fact it was cheaper than copper. However, as more homeowners experienced leakage issues with polybutylene pipes, a chemical reaction was found to degrade the plastic. Chlorine in drinking water reacted with the plastic, causing cracks that led to pipe or fitting failure. These leaks also led to water damage and mold growth in homes across the US.
Around this time, the University of Illinois at Chicago published a study on polybutylene plastic showing that certain chemicals in water react with PB piping, leading the fittings to become brittle, flake apart, and erode. According to the study, these small cracks can deepen with time, eventually causing the pipe to fail.
There are still homes with PB piping installed, so homebuyers and homeowners alike should be aware of potential issues with the material.
How to identify PB piping
Polybutylene piping can be identified by the following characteristics:
- ½ inch to 1 inch in diameter.
- Water supply piping only, not used for drains or vents.
- May be stamped “PB2110”.
- Generally gray or white in color, but may also be blue, black, or silver.
- Found mainly in the southern US.
- May be used as supply lines to plumbing fixtures or a water heater.
- May be used as the main water supply line, underground.
- Typically installed in basements, crawl spaces, and other unfinished areas.
Replacement options for PB pipe
If you believe you have PB pipe in your home, the first thing you need to do is call a licensed plumber. They will confirm the existence of the PB pipe, drain your plumbing system, and inspect the inside of the pipe with a camera to check its condition.
Replacing all water pipes is the best option for dealing with a home that has PB pipe, and replacing them before you have an issue may spare you having to deal with water damage and mold growth later. PB pipe can be replaced with either copper piping or PEX pipe.