This article describes water damage caused by leaking polybutylene water pipe and the cost to tear out and replace the hot & cold water plumbing with CPVC plastic pipe.
Water Damage Caused by Leaking Polybutylene Pipe
A friend’s home was built in the 1980’s when polybutylene water pipe (or tubing) was widely used as a faster and cheaper plumbing alternative versus copper and PVC pipe. The problem with polybutylene pipe is chlorine in municipal water supplies attacks the plastic, causing it to become brittle, resulting in breaks and leaks that can flood the home. Polybutylene pipe is no longer allowed by the Building Codes, but if it’s already in the home there is no requirement to remove it. If you plan on buying a home that was built between 1978 and 1995 have the home inspector thoroughly check for polybutylene plumbing. Otherwise you could incur costly repairs and have difficulty obtaining homeowner’s insurance.
The homeowners were away for the day and returned home to find the house was flooded! A polybutylene pipe in the 1st floor ceiling had burst:
Water poured from the ceiling and flooded the carpet and sofa and into the basement. An expensive nightmare!
The homeowner said it took about 3 weeks to have a flood restoration company dry out the carpets with large fans and dehumidifiers:
Problems with Polybutylene Pipe Leaks
The house was built in 1989 when polybutylene pipe was commonly used for hot and cold supply water plumbing. The homeowner had been plagued by numerous leaks in the polybutylene plumbing system. Most leaks were spot repaired by splicing in a new section of white PEX tubing (see the photo below). After a big leak flooded the house only two weeks after making another spot repair the homeowner was fed up and decided to tear out and replace all the polybutylene plumbing.
The plumber said chlorine in municipal water systems attacks polybutylene pipe which causes it to become brittle and crack lengthwise, resulting in massive leaks. The homeowner believes the polybutylene pipe becomes so brittle that any movement or bending during a splice repair causes a new leak a short distance away.
This home also had the blue polybutylene underground pipe that ran from the water meter to the house. The homeowner said the yard line had been replaced a couple of years earlier after they noticed the concrete driveway always stayed wet.
The polybutylene pipe in this home is a gray colored slightly flexible plastic tube. The pipe connections are made with barbed brass connectors secured with copper crimp bands. The identification marks are on the pipe are:
- PB 2110 – material designation that identifies this as polybutylene pipe
- SDR 11 – Standard Dimension Ratio 11, which defines the pipe size
- CSA B137.8 – Canadian Standards Association mark and CSA standard B137.8 “Polybutylene (PB) Piping for Pressure Applications”
In the above photo, a length of white PEX polyethylene tubing was spliced to repair a leaking section of polybutylene. The PEX tube is connected to the gray polybutylene pipe segment by a barbed brass connector secured with copper crimp bands, which have tarnished to black color. Scratching or filing the crimp band reveals bright copper metal underneath the tarnish. PEX tubing is a quality product that is completely unrelated to polybutylene pipe.
Here’s a closeup of the PB 2110 polybutylene pipe:
I asked the homeowner if they were aware of the class action polybutylene pipe lawsuits and product recalls. They filed a claim but the class action settlement fund had run out of money. Their insurance company covered the water damage but not the cost to replace all the plumbing.
Leaking Polybutylene Pipe Replacement
The homeowners hired a local plumber to replace all the polybutylene pipe in the home with CPVC pipe. (Check with your local Building Dept. for CPVC approval for hot and cold water plumbing. The Building Code may require metal water heater connections.) The cost to remove all the polybutylene plumbing and install CPVC pipe was $2,600.00 plus another $1,000.00 for the drywall contractor. The plumbing repairs required one week for this 2 story, 4 bedroom, 2.5 bath home. The plumber planned the work so the homeowners had water at the end of each day.
PEX water pipe is a very popular solution for polybutylene pipe replacement because unlike PVC, CPVC and copper pipe PEX is flexible and can make bends without elbow fittings, requires no glue or soldering, very reliable and easier to install. PEX is available in different colors with red typically used for hot and blue for cold for easier identification.
Replacing the polybutylene plumbing is a messy and difficult effort because the pipes are concealed inside the walls and ceilings. The plumber started by cutting away large sections of drywall with a utility knife to expose the plumbing and remove the damaged areas:
Cutting away the drywall ceiling to expose the leaking pipes:
Two runs of gray polybutylene pipe are visible in the living room ceiling above the plumber’s head:
The leak occurred when this section of gray color PB 2110 polybutylene pipe that serves the upstairs bathrooms developed a hairline crack. The water is under pressure, sprayed out from the cracked pipe and flooding the house:
The gray polybutylene pipe was removed and replaced with CPVC plastic pipe. Large sections of drywall were removed from the ceilings and walls throughout the house to expose the water pipes:
Numerous access holes must be cut in the drywall to locate the polybutylene plumbing and pipe joints:
Thanks for reading,
Bob Jackson
