The use of terracotta or clay sewer pipes and waste drainage dates back to Roman construction projects. Clay pipes can sometimes survive for up to a century and are simple to produce and lay. However because they are inflexible and brittle, they frequently deteriorate with time and lead to a wide range of drainage issues.

Clay pipe was a common feature of many Australian properties until roughly 40 years ago. While many homes still have clay or terracotta drainage systems, there are now much more robust alternatives, such polyvinyl (often known as “PVC”), that are available. PVC reinforces drain lines and lengthens their lifespan when old or damaged clay sewer drains are replaced.

Typical Issues with Clay Drainage and Sewer Pipes

These are five typical problems with clay drainage pipes:

  1. Workability and weight

Due to their extraordinary fragility and weight, clay sewer drains are challenging to handle, maneuver, and transport. These logistical challenges make laying clay pipes a challenging and time-consuming task for plumbers. Due to its equal weight and durability, PVC pipes are now used by plumbers to repair clay sewer drains since they are much easier to handle.

  1. A root invasion

There are tiny gaps where each segment links together in clay pipes, which makes them not fit together precisely. For thirsty tree roots looking for water, these spaces provide the ideal entrance. These fissures, along with any fractures or diminishing mortar, allow tree roots to enter the drain. Tree roots that have already entered the pipe, sometimes referred to as tree root ingress, continue to develop and eventually obstruct your drain lines.

Your clay drainage system will be more vulnerable to tree root ingression if, when these old clay sewage pipes were first placed, an effective root barrier wasn’t installed or you have large trees growing alongside the drain pipes. And this can only result in costly damage.

  1. Tensile power

Clay pipes hold up well under pressure. However they have a low tensile strength. This means that if they receive a blunt blow or ground vibrations, they could crack or shatter. Broken pipes result in leaks, which could potentially cause your drainage system to fail.

A damaged drainage system prevents wastewater from flowing to the main sewer, where it might stop or stagnate. This in and of itself presents a health risk to those who live close to the problematic pipe. In order to avoid this problem, many plumbers and homeowners will not use clay pipes.

  1. Scaling and Flaking

With time, tiny chips in clay or terracotta pipes gradually get bigger, leading to flaking. Toilet paper and hair are among the items this coating catches and traps inside the pipes. We all know that the two things that harm drain lines the most are hair and toilet paper.

As more dirt accumulates inside the pipes over time, it blocks them. Flaking is difficult to prevent, and in some cases, impossible to correct without extensive rehabilitation work, even with routine drain inspections.

  1. Crooked Pipes

You will experience drainage problems if the pipes are out of line as a result of vehicle movement, ground movement, or incorrect coupling and fitting. The result of misaligned pipes catching and trapping material is a partial or total obstruction of your drains.

One misplaced pipe will frequently displace the next, leading it to go out of place, creating an undesirable domino effect. This problem originates from the rigidity and harshness of clay drainage systems. Clay drainage pipes are simply immobile; even a small force or movement of the earth could cause them to become out of alignment.

Can Hydro-jet Rodding Damage Clay Sewer Lines

Cast iron and clay sewer lines are susceptible to rust and other basic problems, but these problems do not preclude them from being used with hydro jetting. It is nevertheless advisable to ask your plumber to check the condition of your pipes before arranging the service.

How to Repair Your Clay Sewer Pipes

There are several clay sewer drain issues, but fortunately there are current fixes that can fix pipe issues and prolong the life of your drainage system.

Clay sewer pipe damage can be fixed utilizing pipe patching or pipe relining techniques. These no-dig approaches allow for restoration without the need to excavate. Trenchless pipe repairs can be used to repair severely cracked, misaligned, fractured, or joint-damaged pipes. Relining a pipe offers a strong barrier that is long-lasting enough to stop tree roots from entering.

If your property has a clay pipe plumbing system, you can extend the life of your drain by 50 years by repairing and relining pipes with a tough resin coating inside the clay pipe’s structure.

Pros and Cons of Repairing a Clay Sewer Line

There are a number of distinct elements to take into account when determining whether a clay sewage line has to be replaced with another material. Our plumbing specialists are always available to lead you through a discussion of your options if you’re unsure what would be best in your particular circumstance.


  • The greenest option for plumbing systems is clay pipes because they are environmentally beneficial.
  • Acids have little effect on clay pipes.


  • Clay pipes are exceedingly heavy and more challenging to move than PVC, which is lightweight.
  • PVC pipes are seamless, but clay pipes include seams that make them more vulnerable to root invasions. Tree roots expand as they enter a clay pipe joint, crumbling or crumbling the clay as they do so.
  • Clay pipes have a low tensile strength, making them more brittle than other pipe materials and more susceptible to breaking under intense strain.

Speak With Your Local Sewer and Hydro-jetting Specialist

Interested in hydro-jetting? You can reach out to us today at N.W. Sewer and Drain. We’re excited to help you sort out any drain issues you might be facing in your home or office building. Ideally, consulting an experienced local sewer and drain cleaning company should be your following line of action if you are experiencing slow-moving drains, foul odor, or clogged drains in your home and need help figuring out what else to do. 

At N.W. Sewer & Drain, we have a well-trained and ready-to-move team on standby. We serve the Seattle metropolitan area, including Bellevue, Kirkland, Shoreline, Renton, Lake Forest Park, Mountlake Terrace, Auburn, Everett, Marysville, Mount Vernon, and other surrounding areas. 

N.W. Sewer & Drain provides top-notch drain cleaning and sewer repair services in the greater Seattle area, and we’ve been in the business for nearly 20 years. Contact us today at 206-931-7728 to schedule an inspection of your sewer line and pipes.

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