Polybutylene (Poly B) is a gray plastic pipe used as a water supply line in your home. This type of pipe was installed extensively in the early 1970’s until the early 1990’s. It was thought to be a great material at the time, and much cheaper than copper. However, around about the mid-80’s, homes with Poly-B plumbing began to spring leaks. Not good.
If you’re not sure whether or not you have Poly-B plumbing, look for gray plastic pipes anywhere there is exposed plumbing (under the sink, connected to the water meter, or maybe the hot water tank).
One of the problems with Poly-B is that the pipe may look fine from the outside, but it’s slowly deteriorating from the inside, and could rupture at any moment. There’s just no way to tell.
Originally, the problem with Poly-B seemed to be the fittings. The fittings, used to connect one pipe to another, were sometimes made of plastic which cracked and leaked over time. Water pressure was also a problem. If you lived in an area with high water pressure, this could cause an already weakened joint to rupture. Plumbers began using copper fittings, which were great, but there were still problems with leaking. It turns out that Poly-B pipes don’t handle hot water or chemicals, like chlorine, very well, and begin to break down quite rapidly.
What can you do to maintain your Poly-B plumbing?
If you have Poly-B plumbing in your home, it is almost inevitable that you’ll be replacing it at some point. But there are a few things you can do to extend the life of the existing Poly-B:
Replace plastic fittings: As I mentioned above, in the early days of Poly-B piping, the fittings in some areas were made of plastic, and tended to fail over time. This is less common in Canada, than in the U.S. If your fittings are plastic, you might consider getting a plumber to replace these with metal fittings.
Don’t over-crimp: You’ll notice that the pipes are held in place with metal bands. If these are crimped too tightly, hairline fractures could result. With fractures, come leaks, so this is an important step.
Lower the pressure: Pressure-reducing valves are available, and are designed to reduce the water pressure in your house, allowing for less stress on both the pipes and the fittings.
Cool down: Hot water causes Poly-B pipes to deteriorate quicker. You may want to turn down the temperature on your water heater, but be careful; turning it too low can cause bacteria to grow.
What is the life expectancy?
There are many reports that Poly-B piping began to leak around 10 to 15 years after installation. Most experts recommend replacing Poly-B plumbing with the much more durable copper variety. Poly-B is no longer an approved plumbing material under the National Plumbing Code, so is not used in any new plumbing installations.
(They will be eventually)
Although no regulations require the replacement of polybutylene piping with other material, many plumbers recommend doing this, at a cost several thousand dollars. Leaking can happen without warning and can result in flooding and serious damage to a home’s interior if it is not immediately stopped. PB pipes installed behind Drywall can leak unnoticed for long periods of time and cause mould and water damage. InterNACHI believes it is far cheaper to replace polybutylene pipes before they fail and release their contents onto floors, appliances and furniture. Homeowners might face higher insurance premiums or be denied coverage entirely. For homeowners who are concerned about this problem and wish to replace the PB piping in their home with copper or other material, there are companies that specialize in this type of work.