Hugh Cairns: All about Poly B

“Because there is so much misinformation about Poly B piping, this fact sheet will clarify the issues so you will better understand the impact it will have on your home maintenance and improvement budget, and the possible consequences of delaying replacement.”- Hugh Cairns

What is Poly B plumbing?

Polybutylene pipe, or its common name, Poly B, is a flexible grey pipe used in residential plumbing and hot water heating systems. Poly B was manufactured from 1978 until 1998 when the resins that the piping was made of were discontinued. Although available for quite some time, Poly B was used more heavily in BC and Canada when residential construction was strong during the 1980’s and the early-to-mid 90’s. Unconfirmed estimates cite that there are in excess of 200,000 homes in BC with Poly B water systems and some 700,000 homes across Canada that have Poly B installed. Independent reports indicate that Poly B was installed in more than six million homes during the 80’s and early 90’s in the U.S. As you can imagine, I inspect several homes every month with Poly B piping.

Poly B supply piping was the first generation plastic piping system that was designed to compete with and be a substitute for copper supply piping. The demand for Poly B was driven by escalating copper prices making the pricing of Poly B attractive. Poly B was also chosen because it was less labour intensive to install than copper.

Here in Canada, Poly B was originally tested and certified by the Canadian Standards Association (CSA) as an acceptable product for potable water systems. As of 2005, the NRC-CNRC National Plumbing Code de-listed Poly B as an acceptable plumbing piping material. NRC-CNRC plumbing codes are not retroactive, so previously acceptable products that are not currently listed still remain acceptable as long as the product does not pose a health/safety hazard.

There has been much to do regarding the reliability and use of Poly B. Although the system has performed as originally designed and intended in many homes, Poly B has struck controversy in those that have experienced failures and that has influenced the way underwriters view homes that have Poly B plumbing systems.

There are two primary components to the Poly B plumbing system, the grey piping and the connection fittings used to join the pipes.

Poly B plumbing problems

It is important to realize that all plumbing supply systems experience failures. All plumbing systems may fail without warning and in some cases cause interior damage, however contributing factors that may cause Poly B failures centre around connection failures, pipe failures, water quality, age, and faulty installation.

Contributing factors that may cause Poly B failures include:

  • The use of acetal (grey or white plastic) insert fittings to connect the pipe rather than preferential metal ones
  • Over crimping of aluminum bands that result in hairline cracks in the fittings
  • Poor installation near heat sources and hot water tanks, and in areas of excessively high temperatures
  • Improper installation that caused stressed piping
  • Applications where relatively high levels of free chlorine are used

The Canadian experience with the two primary Poly B components has been much different than that of consumers in the United States. Consumers in the southern United States have experienced problems due to installation related issues and product performance. Many U.S. failures occurred in southern areas where plumbing was run in attics (a practice not used in Canada) where the piping can be literally baked by excessive heat and in areas with excess chlorine or chemical content. Consumers in BC and Canada had their Poly-B piping installed correctly using copper or brass metal insert fittings and soft copper crimping rings, not the plastic insert fittings with either aluminum or copper bands which are reported to be more susceptible to failure as used in the States.

Where Poly B has been used with hydronic heating systems, instances of oxygen entering the system through the walls of the piping have been reported. The problem here is that oxygenated water circulated through the system can rust out the metal components expeditiously.

Poly B lawsuits

Although litigation was successful in particular Poly B cases, my research concludes that the avenues of recourse are closed. The deadline for reimbursement in Canada was available only if you completed a complete system replacement by May of 2005 or within 15 years of the date of the original Poly B system install, whichever was later. Even at that, the reimbursement made available was for 25% of the cost of replacing the entire Poly B plumbing system and 25% of any previously unreimbursed damages incurred as a result of a leak in that system, and then, only if you met certain requirements.

Poly B lawsuits are now considered old news. The class action lawsuits have gone away and many old websites are now no longer active. Unfortunately for many readers of this article, it may be a fresh issue for you but old news to the matter.

What can I do if my home has Poly B?

To help preserve the service life of the current Poly B system you should ensure that the operating pressure of the system is safely between 40 and 60 psi. Most plumbing codes require water pressure reducing valves on domestic systems where the municipal water main’s pressure exceeds 80psi. Higher pressures could rupture pipes, damage fixtures, and possible injure the people using them. You can test your interior water pressure with a 3/4″ hose thread test gauge that you can screw on to the same bib used by washing machines. If you can’t make that connection, you can purchase adapters to make a connection at an alternate interior faucet.

Next, you will want to confirm that the operating temperature of your hot water supply system is significantly lower than 180º F. Excessive temperature can have adverse effects on Poly B. Use the lowest water temperature allowable. Most applications require specific water temperatures that must be met. Be sure to meet these, but avoid setting the water heater at temperatures in excess of this.

Ultimately, the only way to completely eliminate the isolated chance of a failure is to replace Poly B components. Specialists have developed methods to cause minimal alterations during the remediation process that cut time and costs. In the majority of cases the work can be accomplished with a tight schedule and leave the system operational at the end of each work day.

Most home owners that choose to replace their Poly B system will most likely choose the newest generation polybutylene system, PEX. Cross-linked polyethylene (PEX), shares many of the same qualities as Poly B, but with an improved cross-linked molecular structure that greatly reduces the deformation of the tubing under stress and temperature than its predecessor. Unlike Poly B, PEX pipes are not softened by heat once they are formed. Also, the connection system has been safeguarded with engineered matching components.

Repairing Poly B

If you have Poly B and you need to repair it or modify the system you’ll most likely convert to PEX piping. Copper conversions are available but often incur extra cost for both labour and material. Poly B pipe and fittings are no longer available, so you have to convert.

Hugh Cairns Poly B tip…..Adapter fittings and crimp rings are available from plumbing suppliers. You’ll need a crimp tool to make the connections. When converting from Poly B to PEX you’ll notice that the crimp rings are different colours. Be sure to place the correct end of the adapter fitting in each pipe and use the correct crimp ring at each connection.

Cost for replacing Poly B

With over 700,000 homes in Canada with Poly B it would be convenient to have a simple formula for pricing out the cost of replacing Poly B pipes. Since there are so many variables in construction techniques a simple formula is impossible to devise.

Hugh Cairns Poly B replacement tip…..The cost of replacing Poly B pipe is best estimated by the person or company doing the work. You’ll need to consider materials, labour and interior access and remediation. Replacing Poly B pipe is almost always invasive but not as bad as one would think. There are plenty of solid techniques that you or your contractor can use to minimize the plumbing path and access.

The cost of replacing Poly B can be likened to the cost of several routine home maintenance items such as re-carpeting your home or putting on new roof shingles. If you are in the position to re-pipe the home, and you weren’t prepared, it’s an unfortunate position to be in. But it really is similar to other maintenance items, perhaps one you didn’t expect.

The cost of replacing Poly B is a good investment in your home. You will realize peace-of-mind and increased value to your home.

Poly B and house insurance

Homeowners’ insurance is a necessity, something every property owner should have. If you have a mortgage, your lender will require coverage — and if your home is mortgage-free you should have coverage anyway.

The usage of Poly B has raised concerns within the home insurance industry regarding their risk exposure. Not surprisingly, the residential insurance industry is approaching the issue in much the same way that they do with other residential risk categories. As a result, some homeowners are finding insurance companies are offering varying opinions and different reactions to underwriting Poly B coverage when it comes to renewal or new policy time.

Clients are experiencing a full range of responses regarding the presence of Poly B and the home’s insurability. In some cases Poly B is treated as trivial, in others, Poly B has resulted in higher insurance premiums. Some clients have reported that the deductible for this condition exceeds the cost of replacing the entire Poly B system. In some cases, requests for insurance have been denied by a particular insurer leaving clients to scramble for an insurer that will underwrite for them.

If you are presently insured, water damage of all sorts is typically covered by most policies. When a home experiences an insurance claim the underwriter regularly adds the claim to a database associated with the property. Should you experience a Poly B insurance claim (or multiple claims) your insurer may decide to increase your premium, your deductible, or worse yet, may not renew your policy. Remember, this action can happen as a result of any casualty, such as fire or weather damage.


Poly B and buying a house

The discussion of Poly B and its relation to insurance underwriting often occurs well ahead of purchase offers. Should the presence of Poly B be determined in the home that you intend to purchase, you should initiate dialogue with your insurer immediately. The presence of Poly B may affect the underwriting of the home and your acceptance of the terms offered to you by your insurer.

If you have previously bought a house or you are a first time home buyer, you probably know that the process of purchasing a home is not like buying anything else. Once your purchase a house, there is usually no option to return or exchange it if you don’t like it.

Because of the finality of buying a home, usually there are several standard optional conditions that must be met before the deal can be closed. These conditions include subjects like financing arrangements, home inspections and insurance. Contingencies are considered a matter of course in real estate transactions and their presence within a purchase agreement is designed to protect the parties involved.

Poly B and home inspections

Virtually all homes have some cosmetic and routine functional defects that can be corrected easily. When buying a home, your home inspector should help you prioritize what to repair in the short term and what you can leave for later. A home inspection will not determine if a Poly B plumbing system is about to leak, but it can look for conditions that promote its reliability and longevity.

Most home inspection clients find that it is prudent to share the report and findings regarding the home with their realtor or designated representative because of its significance in negotiating the agreement of purchase and sale. When the presence of Poly B is determined, the condition should be discussed with your insurer and realtor for advice.