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Older Houses
Polybutylene Pipe: The Gray Plastic Line in Many Older Homes
Polybutylene pipe is a gray, flexible plastic supply line used in millions of homes from the late 1970s; the settlement that paid for replacements stopped taking claims in 2009, so today it is a question for your plumber and insurer.
Polybutylene pipe, usually shortened to PB, shows up in houses across Seminole County and north Orange County built from the late 1970s into the mid-1990s. A 1994 University of Arizona water newsletter described it as a flexible, easy-to-cut gray plastic joined with crimp connectors, used in about six million U.S. homes. If your house dates from that era and has never been repiped, it is worth finding out what is in the walls.
How can I tell if my house has polybutylene?
Often you can't tell from the fixtures. The same newsletter noted that the short stubs coming out of the wall to sinks and toilets were usually copper, joined to the PB with poly-to-copper connectors, so a quick look under the sink can fool you.
Better places to look are where long runs of pipe are exposed: at the water heater, in the attic, in a garage wall, or where the water line enters the house. Gray flexible plastic with crimp rings at the joints is a strong hint. You may see color and stamp tips online, but we could not confirm them from any government or university source, so we leave them out. A licensed plumber or your home inspector can confirm the material.
What was the Cox v. Shell settlement?
It was the big class settlement over PB plumbing. Cox v. Shell Oil Co. was a Tennessee state court case, and a federal appeals court later described the 1995 national settlement as requiring Shell and Hoechst to put in $950 million to replace eligible leaking PB systems and pay for leak damage. A separate Alabama settlement, Spencer v. Shell, covered DuPont.
To qualify under Cox, the indoor system had to be installed between January 1, 1978 and July 31, 1995, using PB pipe with insert fittings of plastic or metal. A PB yard service line, the line from the meter to the house, could have any type of fitting.
Cox v. Shell at a glance
| Item | What the settlement records say |
|---|---|
| Installation window | January 1, 1978 to July 31, 1995 |
| Indoor system | PB pipe with plastic or metal insert fittings |
| Yard service line | PB pipe, any type of fitting |
| Leaks that did not count | Valve or riser leaks fixable without opening the wall; ice-maker line leaks |
| New claims | Closed May 1, 2009 |
| Claims office | Closed December 31, 2009 |
Can I still file a claim for polybutylene pipe?
No. The settlement administrator's site said that as of May 1, 2009, the deadline for all new Cox v. Shell claims had expired, and the claims office closed on December 31, 2009. You may see a later date on other websites; we go with the administrator's own notice.
Even back then, not every leak counted. The guidelines excluded a leak in a valve or riser that could be fixed without opening the wall, such as under a sink, and ice-maker line leaks.
Why did polybutylene get a bad name?
The arguments were mostly about the joints. In that 1994 newsletter, one contractor estimated that about 90 percent of PB leaks were at joints. A researcher who did lab work for the makers found that the acetal plastic used in older joints weakened in the presence of chlorine-type oxidants in tap water, while noting that nobody had tested the pipe itself.
The makers blamed most failures on poor installation, such as crimp bands set too tight, and that view was disputed. The settlement's photo page even sorted fittings into qualified and non-qualified types. For a homeowner today, the practical point is that the pipe in your walls is now at least about 30 years old, and its joints are where a plumber will look first.
Will polybutylene affect my homeowners insurance?
It may, so ask your agent before you shop or renew. For Citizens policies taking effect from February 1, 2022, any home older than 20 years needs a four-point report that looks at the plumbing, and the inspector will note what the supply pipe is made of. Citizens' full underwriting rules sit in agent-only manuals, and its public bulletins say they may be out of date, so we can't tell you exactly how it treats PB today. Your agent can.
Should I replace polybutylene before it leaks?
That is a call to make with a licensed plumber and your insurer, not from a headline. Some owners repipe when a 4-point report or a leak forces the issue; others plan it with a remodel. Ask the plumber what the new lines would be, how they would be routed, and whether the job needs a permit. Seminole County's building division says its permit list is illustrative only, so call if you're unsure.
Until then, know where your main shutoff is and run the free meter check from our slab leaks story now and then. A rising bill is often the first clue; our high water bill story explains how to chase it down. Check any plumber's license before work starts, as our hiring a plumber story describes.
Readers often ask
My house was built in 1996. Could it still have polybutylene?
It is possible but less likely. The Cox settlement covered systems installed through July 31, 1995, which tells you when PB was in wide use, not that it vanished overnight. Have a plumber or inspector confirm.
The pipe under my sink is copper. Does that mean I don't have PB?
Not necessarily. The stubs to sinks and toilets were usually copper even in PB houses, so check exposed runs at the water heater, attic or garage instead.
Is there any money left from the polybutylene settlement?
No new Cox v. Shell claims have been accepted since May 1, 2009, and the claims office closed at the end of 2009.
Is gray PB the same as the gray pipe on my irrigation system?
Don't assume so. Irrigation lines use several kinds of plastic. Ask a licensed plumber if a gray line runs into the house itself.
Do I have to tell a buyer my house has polybutylene?
We aren't able to give legal advice on disclosure. Ask a Florida real estate attorney or your agent, and keep any inspection report that names the pipe type.
Where this came from
- University of Arizona Water Resources Research Center — Arizona Water Resource, Nov-Dec 1994 — what PB looks like, copper stubs, joint leaks, lab findings on fittings
- U.S. Court of Appeals, 5th Circuit — Richard v. Hoechst Celanese, No. 02-41377 — Cox v. Shell background and $950 million settlement, Spencer v. Shell
- Consumer Plumbing Recovery Center — Guidelines (archived 2005) — installation dates, fitting rules, excluded leaks
- Consumer Plumbing Recovery Center — Photographs (archived 2005) — qualified and non-qualified fittings
- Polybutylene Pipe Settlement Fund — home page (archived 2010) — May 1, 2009 claim deadline; office closed Dec 31, 2009
- Citizens Property Insurance — 2022 rates and rules bulletin (archived) — 4-point inspection for homes over 20 years old
- Seminole County Building Division (archived 2026) — permit list is illustrative