Poly-B History

History and Widespread Use

From 1985 to 1997, Polybutylene, commonly known as Poly-B, was a popular choice for plumbing in residential and commercial buildings across North America. Favoured for its low cost and lightweight nature, it was seen as a modern alternative to traditional copper pipes. However, what seemed like a reliable solution quickly revealed its fundamental flaw: a high failure rate. This led to its eventual discontinuation and a ban in Canada in 2005, after being used in over 700,000 homes.

Why Poly-B Fails

The primary reason for the failure of Poly-B plumbing is its unstable molecular structure. The pipes are prone to cracking under various environmental stresses, making their failure a matter of "when" not "if." Several factors accelerate this deterioration:

Chlorine Content: The chlorine used to treat municipal water supplies chemically reacts with the polybutylene, causing the pipe material to become brittle and crack from the inside out.

UV Light & Heat: Exposure to sunlight during transport and storage, as well as high water temperatures within the plumbing system, can significantly weaken the plastic.

Installation & Manufacturing: The failure rate can also be influenced by where the pipes were manufactured (hotter climates can increase failure rates) and the methods used during installation, such as over-tightening of fittings.

Legal and Insurance Implications

The widespread failure of Poly-B plumbing has had significant legal and financial consequences. The material was at the centre of numerous class-action lawsuits, although most legal claims have now expired. The settlements that resulted from these lawsuits, such as one against manufacturers Shell and Dupont, only covered a fraction of the total costs for damages and replacement.

For homeowners, a major challenge is with insurance. In 2005, the Supreme Court of Canada ruled that insurance companies are not legally obligated to provide coverage for homes with Poly-B piping. While some may have offered "grandfather clauses" in the past, many insurers are now refusing to renew policies or insure new clients due to the high risk and losses they've incurred. If a homeowner can find an insurer willing to provide a policy, it often comes with substantial premiums and high deductibles after the first leak. This makes selling a home with Poly-B plumbing difficult without first addressing the issue.

The Replacement Process

Due to the material's 100% failure rate, the only permanent solution is to completely replace the system. Patching or repairing a single leak is not recommended as it's a temporary fix, and other sections of the piping are likely to fail soon after.