Polybutylene Piping in Our Homes

Home Inspection Plumbing Solid State Inspections

Running water is something we give very little thought to everyday but it is a luxury of modern life we could not do without. Getting our indoor plumbing and running water working right has been a challenge for thousands of years. There are many scholars that partially blame the fall of the Roman Empire on health issues from lead pipes used for drinking water. So why is it home inspectors get so concerned when we see Polybutylene piping in a home inspection?


What is Polybutylene Piping?

Polybutylene, is a type of plastic pipe which was in popular use in the 80‘s and 90‘s as the ‘pipe of the future’. Sold on large rolls, it was easier for plumbers to work with than copper, it was less expensive in material cost for builders and home owners than copper, and even the Canadian Standards Association (CSA) had approved it for use in Canada.


What were the Problems with Polybutylene?

There are three main concerns with PB:

  1. Permeation of Oxygen and Rust - Polybutylene is very permeable to oxygen passing through the walls of the pipe, particularly when warm. The extra oxygen that penetrates speeds the natural rust process on metal surfaces inside hot water tanks and boilers significantly. Boilers that should last 40 years have been known to fail in less than 5 years when connected to PB piping.
  2. Material Erosion and Leaks - Water flowing through our piping carries small amounts of impurities which want to erode our pipes from the inside. PB pipes themselves are ok but the erosion effect in the acetal fittings, amplified by chlorine which is used as a disinfectant in many municipal water supplies, caused premature failure at the joints. Leaks in PB piping can be catastrophic failures or micro leaks. Both can be very expensive to repair as catastrophic leaks do a lot of damage quickly, but micro leaks can grow mould and cause rot on hidden structural elements for years before detection.
  3. Production and Installation Quality Control - All products designed for use in construction require quality control at both the manufacture and installation to perform as intended:
    • Manufacturing Defects - There have been many law suits in North America due to failures in PB plumbing systems. Some of these cases have produced evidence that some manufacturers knew they were producing a faulty product and did not address the issues.
    • Installation Failures - In the course of the many investigations into failed PB piping systems, manufacturers were able to identify incorrect installation techniques of fittings, crimp rings, and piping placed in incompatible locations (e.g. attics). Incorrect installation may be the largest reason for widespread PB failure.


How do I know if I have Polybutylene pipes?

Example of PB Piping

PB Piping

The Polybutylene used in Canada was typically greyish blue in colour and had the CSA stamp on it along with manufactures information, typically written in blue. It is normally visible under sinks but the best place to look is in unfinished areas of the home. The age of your home (or last major renovation) is also an indicator of probability. PB was used some in the 70‘s but it was in common use later in the 80‘s and 90‘s.


There are other types of plastic piping in use in homes that do not have the same negative issues as PB. Just because you may see plastic piping does not mean you have a problem. If you are unsure if you have PB piping and are concerned, call in a home inspector or plumber who are experts at identifying these plumbing materials.


What do I do if a Home Inspection Reveals Polybutylene Piping?

Polybutylene piping presents a higher risk of plumbing failure than copper or the newer common plastic piping, PEX. I have two schools of thought on this issue for clients:

  • Re-Pipe the whole home - This is the best solution as it completely replaces all the PB, commonly with PEX plastic piping. We’ve heard of jobs in our area running $3,500-5,000 on typical homes but costs will vary based on the complexity of the job and how much drywall and paint repair after will be required. If you were going to paint every room anyway, this may be a good time to do the re-piping. Always get at least three quotes before selecting a contractor
  • Live with the Risk - Buying a house with PB piping means buying a house with a higher risk of leaks, but it does not guarantee leaks. It is estimated 700,000 homes in Canada out of about 13 million have PB piping or just over 5%. If you are buying a house from the 80’s or 90’s, it could be as high as 1 in 4. People every day live with higher risk in their homes from PB, Aluminum wire, or a plethora of other issues


There are no perfect homes in a home inspection and buyers will always have to assume some risk when buying a home. If you discover PB piping in a home inspection it should raise a good discussion with your home inspector and Realtor about managing the risk, but with the right plans in place, you can own the home you are dreaming of.


By James Bell - Owner/Operator of Solid State Inspections Inc.


Disclaimer: Polybutylene piping carries risks that require professional attention. If you learn you have polybutylene piping in a home inspection or at any other time, always consult a Plumber to help you understand your options for managing plumbing risks. Insurance companies may require a premium if you have PB piping in your home.