From the mid 80's through to 1997, Polybutylene (Poly B) piping was widely installed in homes built in North America. Poly B is a grey piping, with the designation PB2110 printed on the side, as well as the CSA standard identifier B137.8. This piping, along with other flexible plastic piping, gained popularity because of the rising cost of copper and ease of installation. It’s estimated that over 700,000 homes were built in Canada, with perhaps 200,000 here in BC, containing Poly B piping.

Any plumbing system may suffer sudden unexpected failure, but when considering the purchase of a home with Poly B, you must be aware of the increased instances of failure with this type of piping. Poly B is no longer used in new construction.

Some Poly B Piping History

Problems began to develop with Poly B piping after less than 10 years. Leaks were being reported, and worse, undetected leaks went un-noted leading to rot, structural damage and mold growth. The piping is known to deteriorate from within so, often, compromised areas are not visible.  Leaks can also occur at fittings if the crimps were improperly performed or if the fitting itself failed. Class action lawsuits were mounted, to compensate homeowners, which cost Shell Oil Company $1 billion in settlements. Claim submissions for all class action suits have now been closed.

There were a number of contributors to failure, such as:

• Acetyl (grey or white plastic) fittings at connections and bends would crack either on their own or because of over-crimping the aluminum bands holding them in place
• Water pressure that was too high (above 60 PSI)
• Water that contained too much chlorine (added to city water to retard bacterial growth)
• Piping installed bent or with too much strain
• Piping installed too close to a heat source, or in areas that experienced excessive heat
• Piping installed directly to hot water tank
• Water that was too hot (hotter than 130F); 55C/130F is the minimum water temperature as recommended by BC Hydro to prevent bacterial growth

In Canada, acetyl fittings were rarely used. The piping was installed with copper or brass fittings using copper crimp rings, which was the better system, and experienced fewer failures. However, in areas where high chorine levels exist, or where the hot water tank is set to higher than 55C/130F, the pipe itself can be compromised, deteriorating from the inside out. This makes it impossible to visually detect problem areas. Homes that have higher than the recommended 40-60 PSI water pressure are also vulnerable to failures. Poly B should never be directly connected to the hot water tank. There should be an 18” copper leader before the Poly B connection.

The semi-good news is that knowledge is power and Poly B doesn’t have to be the demise of your dream home deal. While there are no guarantees, there are methods to help preserve the Poly B in your home, including:

• High chlorine in the area? Add a filter at the home's water supply entrance
• High water temperatures? Lower to 130F
• High water pressure? Have a new Pressure Reducing Valve (PRV) installed to insure that your pressure is between 40-60 PSI
• Support existing piping every 3-4 feet
• Replace any plastic fittings with copper or brass
• Too close to a heat source (gas furnace or gas hot water tank vent)? Place a heat shield between piping and heat source

If replacement is desired, do your homework and shop around for a company that specialized in Poly B replumbing/repiping.  These companies are often a one stop shop with in-house drywallers. Be sure you ask about their warranty. Expect a 7-10 day turnaround. While it’s not a visible upgrade, it will certainly increase the value of your home and give you peace of mind.

Finally, let’s take a look at Poly B and hydronic heating systems (in-floor radiant heating). Hydronic systems are not manufactured with corrosion resistant components. They are intended to recirculate the same water over and over again. These systems are not designed to carry oxygenated (fresh) water.

Poly B is oxygen permeable, meaning it allows oxygen into the circulating water via absorption through its walls. This oxygenated water will corrode system components, causing premature failure. Hydronic systems should NOT be plumbed with Poly B piping.