Polybutylene (PB) is a plastic manufactured between 1978 and 1994 for use as piping in home plumbing systems. It offered plenty of advantages over other materials such as flexibility, ease of installation, resistance to freezing, and it was inexpensive. Pipes made from polybutylene were installed in 6 to 10 million homes in the Unites States during that period. Despite its strengths, production was ceased in 1994 after scores of allegations surfaced claiming that polybutylene pipes were rupturing and causing property damage. In the homes that still contain this material, homeowners must either pay to have the pipes replaced or risk a potentially expensive plumbing failure.
How Does Polybutylene Fail?
Two studies in particular in papers published by the University of Illinois at Chicago have shown that certain disinfectants can react with the polybutylene and cause it to flake apart at any location within the PB piping system. Small fractures can deepen over time and eventually work their way to the pipe's exterior, allowing water to escape. Some manufacturers, however, claim that the majority of leaks occur at joints and unions, which is where a leak would likely appear if a pipe were improperly installed. Despite this contention, class-action lawsuits filed against PB manufacturers have been successful and resulted in payouts to homeowners reaching $1 billion.
Polybutylene Pipes Should Be Replaced
Although no regulations require the replacement of polybutylene piping with other material, many plumbers recommend doing this, at a cost several thousand dollars. Leaking can happen without warning and can result in flooding and serious damage to a home’s interior if it is not immediately stopped. PB pipes installed behind sheetrock can leak unnoticed for long periods of time and cause mold and water damage. InterNACHI believes it is far cheaper to replace polybutylene pipes before they fail and release their contents onto floors, appliances and furniture. They can also reduce a home’s value or prolong its time on the market. Homeowners might face higher insurance premiums or be denied coverage entirely. For homeowners who are concerned about this problem and wish to replace the PB piping in their home with copper or other material, there are companies that specialize in this type of work.
An inspector can use the following tips to identify polybutylene plumbing. Polybutylene pipes are:
Other piping materials not to be confused with PB:
If in doubt, a licensed plumber can be contacted to determine whether or not a pipe is made from PB.