11/18/2021
Poly-B plumbing: The complete guide
Do you know what kind of plumbing is hidden inside the walls and floors of your home? It’s not something you think about a lot, if it’s working properly. But if your home has Poly-B plumbing, you definitely want to know about it. Odds are, it’s already caused some problems.
What is Poly-B plumbing, what does it look like, and why is it such an important issue? Read on to find out.
Poly-B
Topics
What is a Poly-B?
Identifying it in the home
Risks and what to do if something goes wrong
Costs to replace
Maintenance and life expectancy
Poly-B lawsuits
Home insurance considerations
Commonly asked questions
What is Poly-B (Polybutylene) Plumbing?
Poly-B (short for polybutylene) pipes were, at one point in time, a popular material for home plumbing systems.
From the early ‘70s until the early ‘90s, Poly-B piping was installed extensively in new homes. At the time, plumbers thought it a fantastic material. It was flexible, easy to install, and much cheaper than copper.
However, by the mid-‘80s, a pattern started to emerge: homes with Poly-B plumbing were experiencing leaks. Some Poly-B plumbing would leak slowly — hidden behind drywall — and the homeowner wouldn’t discover it until it was too late. These homes had not just water damage, but also mould.
There are as many as 700,000 homes across Canada with Poly-B plumbing.
How do you tell if your home has Poly-B?
Most Poly-B pipes are grey, though other colours (like black, white, or blue) exist.
If you’re not sure whether you have Poly-B plumbing, look for gray plastic pipes anywhere there is exposed plumbing: under the sink, connected to the water meter, at the hot water tank, or on the ceiling of an unfinished basement.
Poly-B plumbing systems often have plastic fittings connecting the lengths of pipe, though copper fittings appear sometimes as well. Copper- or brass-fitted Poly-B systems are reportedly quite common in Alberta, for example.
Heat pump water heater in a basement
One other way to identify Poly-B plumbing is by the markings printed on the pipes. Poly-B pipes usually have an identifying code stamped on the side: either “PB2110” or “CSA-B 137.8.” The absence of these codes doesn’t automatically mean it’s not Poly-B; if your home’s plumbing meets all the other criteria, it could still be Poly-B.
If you suspect your home’s pipes are Poly-B but you can’t confirm it, contact a plumber to arrange an inspection. With Poly-B pipes, you’re better safe than sorry.
Risks with these types of pipes
The first problem with Poly-B has historically been the fittings.
The fittings, used to connect one pipe to another, are often plastic. These fittings are prone to cracking and leaking over time. In some cases, the fittings weren’t installed correctly. They’ve often been over-tightened, causing the pipes themselves to crack.
Poly-B pipes are also prone to damage from water pressure and heat. Most home plumbing systems have to deal with both of those things, making Poly-B a poor choice.
But wait, there’s more:
Chemicals like chlorine slowly degrade polybutylene. Even in the tiny doses sometimes present in municipal water supplies, such chemicals can harm Poly-B pipes and lead to leaks.
While a cracked pipe often leaks enough that you’ll discover it quickly, degradation from heat or chemicals can take a long time, and it starts from inside the pipe. Poly-B plumbing may appear perfectly fine on the outside while being ready to rupture at any moment. There’s just no way to tell.
What should you do when something goes wrong?
It’s difficult to judge the condition of Poly-B piping. Home inspectors can look for obvious signs, such as visible repairs or improper installation. But damage to the pipes begins from the inside where you can’t see it.
InterNACHI (International Association of Certified Home Inspectors) advises that leakage can happen without any warning. Plumbers recommend replacing Poly-B pipes with something else (such as PEX or copper). Not only might you have difficulty getting insurance, but Poly-B plumbing can discourage potential buyers from purchasing your home if you ever decide to move.
There are things you can do to extend the life of the Poly-B pipes, but most experts say that the best solution is usually to replace the entire system.
Take a look at Jon Eakes’ website. He has asked Canadian homeowners to write in if they’ve had issues with their Poly-B plumbing. It’s quite an eye-opener.
Costs to replace Poly-B Plumbing
The average cost to replace Poly-B plumbing within a home ranges from $3,000 to $25,000.
There are quite a few factors that can raise or lower the cost. Obviously, a larger home with a more extensive plumbing system will cost more.
However, aside from the material and labour costs for replacing the plumbing itself, there’s the added cost of actually gaining access to the pipes. Replacing a whole plumbing system means tearing up flooring and opening walls — an expensive undertaking.
However, if you leave it too long and your Poly-B pipes start to leak, you might find yourself having to pay for remediation of water damage and mould on top of the Poly-B replacement cost.
