If you're in the market for a home in Calgary, there's one hidden feature that could affect your investment more than you think: the plumbing. Specifically, Polybutylene—commonly known as Poly B—was widely used in homes built between the late 1970s and mid-1990s. While it was once a popular choice for water supply piping, its track record has raised red flags for homeowners, inspectors, insurers, and now, you: the buyer.

What is Poly B?

Poly B is a flexible, grey plastic pipe used extensively as a low-cost alternative to copper. It was easy to install and became the standard in many homes across Canada during its heyday. However, over time, it has proven to be susceptible to deterioration—especially when exposed to the chlorine commonly found in municipal water.

Why Buyers Should Be Concerned

Hidden Leaks & Water Damage: Poly B can fail from the inside out, meaning problems may not be visible until significant damage has occurred.
Higher Insurance Costs: Some insurers may charge higher premiums, limit coverage, or refuse to insure homes with Poly B plumbing.
Financing & Resale Risks: Lenders and buyers often request full disclosure. Homes with Poly B may face reduced market value or added negotiation hurdles.
Replacement Costs: Re-piping a home can cost thousands and involve major disruptions (wall openings, drywall repair, repainting).

How to Identify Poly B in a Calgary Home

Pipe Colour: Most Poly B is grey, though black or white variants exist.
Markings: Look for “PB2110” or “CSA-B 137.8” stamped on the pipes.
Location: Check under sinks, near water heaters, and in exposed basement piping.
Home Age: Homes built between 1978 and 1997 are most likely to contain Poly B.

What You Can Do as a Buyer

Ask Directly: Inquire whether the home contains Poly B and request documentation.
Home Inspection: Hire an inspector who knows how to identify and assess Poly B plumbing.
Insurance Check: Get a quote before purchasing to understand potential surcharges.
Negotiate Smartly: Use the presence of Poly B as a bargaining tool. Sellers may agree to a price reduction or complete replacement.

Replacement Options

PEX Piping: More durable and flexible than Poly B, commonly used today.
Copper: Premium choice, but more expensive.

Costs in Calgary for a full Poly B replacement can range from $5,000 to $20,000+, depending on the size and layout of the home.

Final Thoughts

Poly B isn’t necessarily a dealbreaker—but it is a red flag that should not be ignored. The more informed you are, the better positioned you’ll be to make a smart purchase. For professional advice and access to Calgary homes without Poly B concerns, visit CalgaryHomeSelling.ca.