Posted by: Elementary Property Inspections |


At Elementary Property Inspections, as we perform home inspections throughout the Niagara Region, we often identify older homes with cast iron waste piping. They often look to be in good condition. Should the buyer be concerned?

Cast iron plumbing systems originated in France during the seventeenth century, installing the first large-scale cast iron pipes, contributing as the forerunners to Europe’s sewer history. They believed it was the most robust material to transport water and sewage to a certain distance.

If you live in a home that was built before 1970, chances are high that your waste plumbing system consists of cast iron pipes. Cast iron pipes can corrode over time compromising their structural integrity. Installing this material was a highly labor-intensive job that only the wealthy could afford. Up to this day, it’s an expensive method of choice; and for that reason, PVC became the most common choice for building flexible and durable lines in more modern homes.

If you do find cast iron pipes in your home that are several decades old, do not despair. While it’s a durable material, it does fail over time. Therefore, it’s worth having a licensed plumber to inspect it for you. Cast iron pipe repair is common, and certain small holes and leaks can be repaired, depending on the severity of the damage.

This plumbing system is most common in older homes built before the 1970s when people praised its durability. However, no building material is ever perfect and deteriorates over time. Well-maintained cast iron pipes can operate 60 to 100 years, whereas some show signs of wear and tear after 25 years.


  • Strong and durable
  • Resistant to fire
  • High-quality material
  • Can last for decades if housing location has stable weather
  • Less likely to corrode in homes laid in sandy soil (well-aerated soil that doesn’t contain much water)


  • Heavy
  • Susceptible to corrosion:
    • Particularly when laid in clay soil as it holds more water
    • Chemical reaction with sewer gas (oxidation causes sulfuric acid)
  • Expensive repairs
  • Joints may contain lead
  • Prone to sewage backups (due to rust flake buildup in lines)

Although cast iron pipes have been used in many different water systems throughout Canada in the last hundred-plus years, they do deteriorate over time. In addition, they have a lifespan of only between 60 and 100 years. However, they can begin to develop problems at 25 years old, depending on their certain circumstances.

Unfortunately, cast iron pipes are known for easy clogs due to ageing and corrosion inside. If you experience slow draining or sewage backups, a pro should inspect the insides with a sewer video camera to make sure it’s not merely clogged drains. If left untreated, it could lead to more drastic problems in the future. A sewer backup into the home can be particularly detrimental to your property as well as to your health because you could potentially be exposed to harsh chemical additives, bacteria, pathogens, and other harmful substances.

Oxidation degrades metal, leading to cracks that could involve a damaged sewer line. If you smell sewer gas, immediately shut off your water and locate the affected area. It’s better to check if other sections of your line are in good condition. If they are also failing, a PVC sewer pipe replacement would be your most economical solution.

Leaks are another significant concern with cast iron waste lines. Cracked drain lines in walls or floors also increase the level of humidity, enabling mould growth in your home. Untreated mould will continue to multiply and damage your building structure, and worse, pose a serious health hazard.

Although minor repairs may be made to existing cast iron piping, many experienced plumbers have documented significant problems with cast iron pipe repairs. They understand their clients’ passion and nostalgia regarding their old-fashioned plumbing systems. At the same time, plumbers want their clients to have a safe plumbing system that provides longevity and stability, ruling out any unpredictable surprises that will result in expensive future spending.

Ignoring a faulty plumbing pipe system is just an accident waiting to happen, and it could only be a matter of time before you are faced with having to deal with an expensive emergency due to compromised cast iron pipes.

Should I replace all my cast iron piping?

Although it may not be immediately necessary, we know that cast iron pipes are failing all over the country, reaching the end of their 50 – 100 year life-use. Here are eight benefits of replacing them with PVC.

  1. Lightweight – Cast iron is hefty, requiring a few plumbers even to remove them. Compared to cast iron, PVC is light, easy to move, and faster to install.
  2. Cost-efficient – With fewer plumbers needed to install the pipe, that means less labor, heavy material, and shipping.
  3. Flexible – PVC is highly flexible, resistant to movements and shifts in the ground.
  4. Cracks Less Often – Due to the flexibility, PVC is the go-to choice in high pressure and high movement areas. Even with pressure and vibration, PVC remains intact.
  5. Tighter Joints – PVC pipes have the highest joint tightness compared to other types of pipes, such as cast iron and terracotta (clay).
  6. Leaks Less Often – When joints aren’t tight enough, leaks start to occur more than usual. Tree roots have an easier time detecting the water flowing when the joints are weak, causing more problems.
  7. Durable – Polyvinyl Chloride can last up to 70 years or more. Replacing cast iron pipe is expensive as they deteriorate from oxidization.
  8. Cleaner – Because PVC doesn’t corrode or rust, you won’t get any metal in your sewage or drinking pipes. It’s a non-toxic material, safe to use for all kinds of plumbing purposes.

Should You Combine Or Connect Cast Iron With PVC?

The short answer is no. It’s not recommended. Even if you did it yourself, you would need a unique tool to cut the cast iron. Let’s say you only need to replace a section of crumbing pipe with something brand new. The connecting ends If the pipe is somewhere under your home, you will be chipping away concrete and tile, searching for a minor problem, ending up with a huge mess. Cast iron plumbing is becoming outdated, and almost all of them need total replacement before total failure. Although a more expensive option, it may cost you less in the long run.

For a complete Home or Septic Inspection, call us at Elementary Property Inspections, (289) 686-9482 or visit our web site www.elementaryinspections.com