What is Polybutylene?
Polybutylene is a form of plastic resin that was used extensively
in the manufacture of water supply piping from 1978 until
1995. Due to the low cost of the material and ease of installation,
polybutylene piping systems were viewed as "the pipe
of the future" and were used as a substitute for traditional
copper piping. It is most commonly found in the "Sun
Belt" where residential construction was heavy through
the 1980's and early-to-mid 90's, but it is also very common
in the Mid Atlantic and Northwest Pacific states.
The piping systems were used for underground water mains
and as interior water distribution piping. Industry experts
believe it was installed in at least 6 million homes, and
some experts indicate it may have been used in as many as
10 million homes. Most probably, the piping was installed
in about one in every four or five homes built during the
years in which the pipe was manufactured.
How to Tell If You Have Poly
Exterior - Polybutylene underground water mains are usually
blue, but may be gray or black (do not confuse black poly
with polyethelene pipe). It is usually 1/2" or 1"
in diameter, and it may be found entering your home through
the basement wall or floor, concrete slab or coming up through
your crawlspace; frequently it enters the home near the
water heater. Your main shutoff valve is attached to the
end of the water main. Also, you should check at the water
meter that is located at the street, near the city water
main. It is wise to check at both ends of the pipe because
we have found cases where copper pipe enters the home, and
poly pipe is at the water meter. Obviously, both pipes were
used and connected somewhere underground.
Interior - Polybutylene used inside your home can be found
near the water heater, running across the ceiling in unfinished
basements, and coming out of the walls to feed sinks and
toilets. Warning: In some regions of the country plumbers
used copper "stub outs" where the pipe exits a
wall to feed a fixture, so seeing copper here does not mean
that you do not have poly.
Will the Pipes Fail?
While scientific evidence is scarce, it is believed that
oxidants in the public water supplies, such as chlorine,
react with the polybutylene piping and acetal fittings causing
them to scale and flake and become brittle. Micro-fractures
result, and the basic structural integrity of the system
is reduced. Thus, the system becomes weak and may fail without
warning causing damage to the building structure and personal
property. It is believed that other factors may also contribute
to the failure of polybutylene systems, such as improper
installation, but it is virtually impossible to detect installation
problems throughout an entire system.
Throughout the 1980's lawsuits were filed complaining of
allegedly defective manufacturing and defective installation
causing hundreds of millions of dollars in damages. Although
the manufacturers have never admitted that poly is defective,
they have agreed to fund the Class Action settlement with
an initial and minimum amount of $950 million. You'll have
to contact the appropriate settlement claim company to find
out if you qualify under this settlement.