Polybutylene pipe is grey, black or blue.
Interior polybutylene is mostly grey and
exterior polybutylene is mostly blue or black.
Polybutylene pipe was installed and manufactured from the
late 1970’s till the mid-1990’s, however, stockpiles of polybutylene
pipe at supply vendors, such as supply risers
were still known to be available up to 1999.
The most common sizes for polybutylene pipe are 3/8”, ½”,
¾” and 1”.
Polybutylene piping was used for both residential and
commercial water distribution piping.
Polybutylene pipe connectors can be copper, brass, or plastic. The
connector types are barbed with a crimp ring or compression with a
plastic or metal ferrule.
What’s
Wrong With Polybutylene?
Deterioration of the pipe is the main
problem; there have been several studies which have linked the
deterioration to chlorine and other additives to public water.
Polybutylene has a relatively low bursting pressure when compared to
an equivalent sized copper pipe. Most poly-butylene breaks
occur first on lines with higher pressure. In many neighborhoods,
the polybutylene main lines from the meter to the house break
before the interior polybutylene lines
partly due to the higher main pressure. Most homes with interior
polybutylene leaks also have pressure above the Georgia
maximum safe allowable pressure of 80 PSI; this is normally due to a
failed or improperly adjusted pressure reducing valve.
Improper installation can also greatly reduce the life of the
polybutylene system. Most improper installations involve over
stressing the pipe at joints and fittings. The most common
cases of improper installation are piping bent in short radii
(the radius of the original coil is the max radius the pipe is
designed to bent), shearing of the pipe at the foundation wall due
to settlement of the backfilled soil, damage caused by
sharp objects (such as rocks, nails, and hangers), over-tightened
fittings and not enough room left for thermal expansion and
contraction (plastic piping shrinks and expands with temperature
changes).
