What is Poly-B?

Poly-B, short for Polybutylene, is a type of plastic pipe that was commonly used in residential plumbing systems between 1978 and the late 1990s. It’s a flexible, gray tubing that was installed as a cheaper, easier alternative to copper. You’ll often find it behind walls, under sinks, or near hot water tanks in homes built during that era.

Why Is Poly-B Failing?

Poly-B piping has a known history of premature failure, and here’s why:

• Material Breakdown: Over time, Poly-B becomes brittle and prone to cracking, especially when exposed to heat or chlorine-treated water.

• Microfractures: Stress from water pressure, temperature fluctuations, or even minor movement can cause tiny cracks that eventually burst.

• Fittings & Connections: The original fittings (especially plastic or aluminum crimp rings) were prone to loosening or leaking.

• Hot Water Sensitivity: It degrades faster near hot water tanks or any consistently warm zones.

Even if the pipes look fine now, they often fail without warning, which is why so many professionals — and now insurers — recommend full replacement.

Insurance Issues with Poly-B

Many insurance companies have started treating Poly-B plumbing as a high-risk liability, and here’s what that means for homeowners:

• Higher Premiums: Some providers raise rates or require additional riders if Poly-B is present.

• Refusal to Insure: Some flat-out won’t offer coverage on homes with active Poly-B systems.

• Denied Claims: If a Poly-B pipe fails and causes damage, insurers may deny water damage claims if you were aware of the risk and didn’t act.

We’ve had clients come to us after being told by insurance that they must replace Poly-B to renew or bind a policy.

Municipal Code Changes in Alberta

While Poly-B is not officially banned in Alberta building codes for existing homes, it is no longer approved for use in new construction under current plumbing standards.

Here’s what’s important to know:

• New builds must use PEX, copper, or approved alternatives.

• Renovations involving plumbing upgrades often trigger code compliance. That means if you’re opening up walls or remodeling, inspectors may require Poly-B to be removed as part of the permit process.

• Home resale values are being affected, especially in Calgary and surrounding areas where buyers and realtors are aware of Poly-B risks.