The Facts About Polybutylene Pipe Issues

November 16th 2012
The Facts About Polybutylene Pipe Issues

The type of pipe used to plumb and heat your house can make a major difference in the efficiency and quality of your HVAC system. Here's some information about polybutylene pipe and its effects on your home from Shell Busey's Home Improvements and Renovations:

With the heating season upon us, we have received several inquiries to our office from homeowners who are concerned with potential issues arising due to their Polybutylene pipes and fittings.

Polybutylene plastic pipe or Poly-B for short, was installed in homes built between 1978 and 1995. It was used for hot and cold supply piping in homes. Poly-B plumbing and heating systems include polybutylene plastic pipe connected with acetal plastic insert fittings. Polybutylene plastic pipe is usually gray and occasionally black. The acetal plastic insert fittings are usually gray and occasionally white. The fittings are usually held in place with a metal crimp ring on the outside of the pipe.

However, Poly-B has attracted considerable attention over the years because of concerns with its potential to leak. The claim is that Polybutylene pipes and fittings may deteriorate when exposed to hot water and high chlorine residuals in water. However, there appears to be a relatively low incidence rate of failures, most of which have been attributed to poor installation.

If your Poly-B piping is only distributing your domestic hot and cold water throughout your home you should have little to no concern with any potential issues. In this case, I always suggest turning the water temperature down to 130F on the hot water tank.

Consumers concerned about whether or not they have Poly-B pipe in their homes should do the following:

  • Step 1 -- Determine when your home was built. If it was before 1974 and no major plumbing renovations were made, this issue does not apply to you.


  • Step 2 -- Determine whether your home has circulating hot water heating. If you have a forced air system or electric baseboard heating this situation likely does not apply to you.


  • Step 3 -- In an unfinished area of your home where there are exposed water pipes, look for flexible, grey-colored plastic pipe or tubing. The areas to search in your home include:

- Basement: connected to a water meter or to a hot water heater (Note: Poly-B pipe should not be connected directly to a hot water heater.
- Bathrooms: connections beneath the lavatory sink and to the water closet
- Kitchen: beneath the sink

Note: There may be copper piping in some areas and Poly-B pipe in others.

  • Step 4 -- Check to see if the Canadian Standards Association (CSA) mark and CSA standard number "B 137.8" is on the pipe. The following marking should also be on the piping:
    • piping manufacturer identification
    • material designation "PB2110"
    • nominal size and "SDR 11"
    • pressure rating "690 kPa @ 82°C or 100 psi @180°F"
    • date code
    • the word "POTABLE" (to indicate suitability for use in potable water supply)


The National Building Code of Canada requires Poly-B pipe used in residential construction to meet the requirements of CSA standard CAN/CSA B137.8, Polybutylene Piping for Pressure Applications. Poly-B piping certified to these requirements may bear the CSA mark, or the mark of another accredited certification organization.

If you have a hydronic heating system in your home using Poly-B, please contact a hydronic hot water heating specialist and have them assess your system by doing water tests within your system and they will advise you on the next steps to take.

Note: It is very important to have a hydronic heating specialist to address any concerns with these systems

For more information about requirements for and use of Poly-B products, a CSA consumer fact sheet can be found by going to the CSA website