A grey (sometimes blue or black) flexible plastic supply pipe installed in Canadian homes most commonly from 1978 to about 1997, by some estimates in more than 700,000 Canadian homes, as a cheap, fast alternative to copper. It was eventually discontinued and removed from Canada's plumbing code (around 2005) as its reliability problems became clear.
$6,000 to $18,000 to repipe a house (Metro Vancouver often $10,000 to $20,000)Address before purchasePlumbing
The quick answer
Poly-B is the grey flexible supply pipe installed in Canadian homes from about 1978 to 1997. It can fail without warning, and a growing number of insurers won't cover an active poly-B home or will add water-damage surcharges, so it's a before-you-buy conversation and a strong negotiation point. A repipe runs about $6,000 to $18,000 (Metro Vancouver often $10,000 to $20,000). Have a plumber confirm it and check coverage before you remove conditions.
You are reading the polybutylene page. Type the year the house was built and I will tell you what else tends to be true at that age, what it costs, and what to ask. One number, ten seconds.
Free. No account. Educational and impartial, not a home inspection.
Why it matters
Poly-B can fail without obvious warning. It degrades over time, chlorine and other oxidants in municipal water attack it from the inside, and stress concentrates at the fittings, and it can split or leak, sometimes causing sudden, expensive water damage. The two practical headaches for a buyer are that water damage andinsurance: a growing number of Canadian insurers won't cover an active poly-B home, or will add water-damage surcharges, exclusions, or higher deductibles. That combination makes it a before-you-buy conversation, and a strong negotiation point.
How to spot it
Grey flexible plastic supply lines, not white/translucent PEX and not copper, at the water heater, under sinks, and at the main shutoff, joined with plastic or copper crimp fittings. If you can read the pipe it's often stamped "PB2110."
What it costs
Canadian repipes run $6,000 to $18,000 depending on size and access; GTA and other major cities typically $10,000 to $18,000 for a 2,000 sq ft home, and Metro Vancouver $10,000 to $20,000 on higher labour rates. Finished walls and ceilings drive the top end.
What to do
Address before purchase. Have a licensed plumber confirm the material and extent and quote a repipe, and, importantly, confirm coverage with your insurer or broker before removing conditions. Use the quote to negotiate.
Education and triage, not a home inspection. Casaroo flags grey poly-B from your photos, a licensed plumber confirms the type and extent.
Common questions
Will insurance cover a house with poly-B?
A growing number of Canadian insurers will not cover an active poly-B home, or will add water-damage surcharges, exclusions, or higher deductibles. That combination is what makes poly-B a before-you-buy conversation and a strong negotiation point. Confirm coverage with a broker on the specific address.
Is poly-B always going to fail?
It can fail without obvious warning, which is the point. Chlorine and other oxidants in municipal water attack it from the inside and stress concentrates at the fittings. Age and water chemistry drive it, so a plumber's assessment is worth more than a general reassurance.
What does a repipe cost?
$6,000 to $18,000 in most of Canada, and $10,000 to $20,000 in Metro Vancouver on higher labour rates. Finished walls and ceilings drive the top end, because someone has to open them and then put them back.
How do I recognize it?
Grey flexible plastic supply pipe, sometimes blue or black, at the water heater, under sinks, and at the main shutoff. It is not white or translucent like PEX and not copper. Where you can read the pipe it is often stamped PB2110.
Note: poly-B is a discontinued product, so guidance comes from industry and insurers rather than a single government standard; insurer positions vary. Confirm with your broker, and a licensed plumber confirms the pipe. Casaroo flags, it does not inspect.
Last reviewed 2026-07-10.
This guide is general education, not a home inspection and not advice for your specific property. Always
consult the appropriate licensed professional, and get a licensed home inspection before you remove conditions
or buy. Cost ranges are 2026 estimates that vary by region, size, and access; confirm specifics with a
qualified professional.