Does your home have Poly B? The complete visual guide
If your home was built or renovated between 1978 and 1998, a grey plastic pipe may be hiding behind your drywall. Here is exactly how to find out in ten minutes, no tools required.
The 30-second answer
Look at the pipe coming out of the top of your hot water tank and under your kitchen sink. Poly B is a flexible plastic pipe, usually grey, stamped PB2110 along its length. If you see that stamp, you have Poly B.
Where to look: tap each spot
1 · The water heater
The easiest check in the house. Look at the pipes entering and leaving the top of your hot water tank. Poly B here is grey, flexible, and often connects to copper stubs with a visible crimped fitting. Hot water lines degrade fastest, so this is also where failures start.
What you're looking for
- ✓Grey flexible plastic pipe, half inch or three quarter inch. Less commonly blue, black, or silver.1
- ✓The stamp PB2110 printed along the pipe. You may also see CSA-B137.8.1
- ✓Crimped metal rings at the joints rather than glued or soldered connections.
- ✓A home built or replumbed roughly 1978 to 1998. Manufacturers stopped producing the resin in spring 1998.2
One important lookalike: PEX, the modern replacement pipe, is also flexible plastic but is usually white, red, or blue and carries different markings. Grey colour alone doesn't confirm Poly B, and the absence of grey doesn't rule it out. The stamp is the tell.
Alberta and BC installs look different
AB · Alberta homes
Poly B here was typically installed with copper or brass insert fittings and metal crimp rings. That combination has historically failed far less often. Alberta's regulator counted only a handful of failures over 20 years, all tied to improper installation.2
BC · BC homes
BC installs more commonly used grey or white plastic acetal fittings, the component with the worst failure record. Combined with more chlorinated water treatment, BC systems carry the higher risk profile.3
Either way, every Poly B system in Canada is now 28 to 48 years old, at or past its expected service life. The National Plumbing Code removed Poly B as an accepted material in 2005. Existing installations remain legal, since codes aren't retroactive, but insurers treat the pipe as a scheduled risk regardless of province.4
Is your neighbourhood a Poly B zone?
We mapped neighbourhood construction eras across Calgary, Edmonton, and Kelowna. Type any address, yours or a home you're thinking of buying.
Results describe neighbourhood construction eras, not your specific home. Only a visual inspection can confirm Poly B.
Common questions
My home was built in 1989 but I can't find a stamp. Could it still be Poly B?
Yes. Stamps fade, get painted over, or face the wall. If the pipe is grey, flexible, and joined with crimp rings in a 1978 to 1998 home, treat it as Poly B until a plumber confirms otherwise.
Will a home inspection catch Poly B?
Not necessarily. Home inspectors aren't required to identify or test Poly B under standard practice. Many will note the pipe material if visible, but plenty of purchases close with the buyer unaware. Check yourself or ask directly.5
I found Poly B. Do I have to replace it right now?
Not by law. Existing Poly B is legal to keep. The pressure comes from age, failure risk, and increasingly from insurers, who may surcharge, add conditions, or decline coverage. The insurance chapter covers exactly what to expect.
Sources for this page
- Square One Insurance, Poly B plumbing guidance
- Alberta Municipal Affairs, Polybutylene (Poly-B) fact sheet
- Canadian home inspection industry knowledge bases
- National Plumbing Code of Canada, 2005 revisions (NRC-CNRC)
- InterNACHI home inspection Standards of Practice
Facts on this page are drawn from the government, insurer, and industry documents named above and rewritten for clarity. This library keeps everything you need in one place.
Published by Poly B Plumbing Guys
This library is maintained by the team that replaces Poly B every day across Alberta and BC. Red Seal certified plumbers, full remove-replace-restore service including drywall and paint, a 25-year warranty, and the completion certificate insurers ask for.
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