Polybutylene (PB) Piping & Plumbing, Water Pipe Leak

Polybutylene (PB) Piping & Plumbing, Water Pipe Leak

Examples of polybutylene pipes:

Acetyl Plastic Insert Fittings

Polybutylene (PB) pipes , also known as Quest pipes,  might be the pipes running throughout your home that supplies water you use everyday. PB pipes will leak without any warning causing thousands of dollars in damage.

Polybutylene is a plastic material known as a co-polymer. It was widely used from the mid 70’s to the mid 90’s across the nation. At that time it was touted as the «pipe of the future.» Polybutylene pipes are easily identified by the gray color and copper rings around the fittings where there are joints or directional changes in the pipe.

What causes polybutylene pipes to deteriorate can be attributed to the oxidants in the water. Significantly more failures have occurred with the increased usage of chemicals like chlorine and bacteria fighting ingredients we use everyday. Polybutylene piping reacts to these oxidants by becoming brittle. The PB pipes then develop tiny micro cracks in the pipe. Just looking at the pipes may not give you any indication that there is a problem because the erosion and cracks start on the inside of the pipe. Be aware, what appears to be okay, may not be!

PB pipe failures can range in severity, but once you find one leak you can be assured you will soon have more. The average PB pipe starts to leak after nine years. The older the pipes the more likely they are to fail. With polybutylene it is not a question of IF you will have a failure but a question of WHEN you will have a failure. It is important that you become pro-active in your efforts to prevent failures and the damage one failure can cause to your home.

How do you recognize Polybutylene Pipes:

The most effective way of identifying polybutylene pipe is to have your plumbing inspected by a licensed professional. While inspectors generally cannot determine if there is deterioration in polybutylene piping, licensed plumbers can confirm if you have polybutylene piping installed in your home.

Typical characteristics of polybutylene piping include:

    PB pipe is a non-rigid, sometimes curved, usually gray (or possibly silver or black) plastic pipe used in water supply plumbing systems. PB pipe has copper or silver (aluminum) rings that hold the joints together. PB pipe is blue, gray or black when used in the underground service company (from your home to the street). PB pipe is not used for drains, waste or vent piping. PB pipe is not PVC or CPVC. which is a rigid white or off-white plastic pipe.

Polybutylene piping can be used anywhere in your home’s plumbing system; usually, its presence can be ascertained by checking the attachments under household sinks, near hot water heaters or leading into toilets. Following is an overview of common places you may want to inspect for the presence of polybutylene piping:


    Look above or around& the water heater. Usually, there will be two 18″ copper pipes pertuding out of the top of the heater.  Just above the copper pipes, you should see the gray PB pipes. Crossing unfinished basement ceilings. Look for the PB pipe to run along the bottom of the ceiling joists. Feeding sinks, toilets, and bathtubs. You should see the gray plastic pipes under sinks and at the toilets. However, some contractors would «stub out» in copper. If that’s the case, you will not see the PB pipes or shut-off valves.


Another important area where polybutylene piping may have been installed is the incoming water supply line to your house. If the incoming pipe is a light blue plastic pipe, it is likely that you have a type of polybutylene pipe informally called “Big Blue”. This pipe is extremely prone to failure and unexpected bursting. If you have this type of pipe as an incoming water supply line, it is recommended that you have it replaced as soon as possible.

    Entering the home through basement walls. The pipe can usually be found along the front wall of the home. A good starting point is to look where your front hose bibb is located relative to the front of the house.  Many contractors would have installed the hose bibb next to the main shut off. Attached to your home’s main water shutoff valve. Look just below the valve. Many times, the pipes on either side of the main shut off will be something other than PB. It is mportant to look where the pipe enters the house. If you see a blue pipe coming out of the foundation wall or basement slab, chances are, you got «Big Blue» polybutylene pipe. Attached to your home’s water meter (often a copper pipe at a water meter will be attached to polybutylene pipe somewhere underground, so it is wise to check both ends of the pipe)

Leave a Reply