Cast Iron Pipes Explained – Applications, Advantages, and Disadvantages

Cast iron pipes are made by cutting and forging grey cast iron into a round shape with a hollowed center. Back in the day, this piping system was the standard for transporting gas, sewage, and water in residential and commercial properties. Despite the new materials, cast iron pipes are still used in commercial construction. However, with time, they can fall apart or corrode with waste and wreckage without maintenance and cause various plumbing problems like leaks, slow water drains, and stoppages that may require a costly repair.

Cast Iron Pipes Video

Property managers, if you have slow water drainage, frequent leaks, and stoppages… Let me show you one likely culprit. These are cast iron pipes.🚰 They’re sturdy when new, but over time they corrode and crumble which makes them ticking time bombs beneath your property. On top of that, they tend to get packed with decades of debris which causes backups, more leaks, and mold growth which can lead to potential health issues. 🤢

Here’s our recommendation:

Make sure you’re getting your plumbing system regularly inspected and maintained by a qualified plumber, that way we can prevent costly property damage, and recommend exactly when your cast iron pipes need to be replaced entirely.

History of Cast Iron Pipes

The cast iron pipes were first used in Versailles, France, in 1668, under King Louis XIV’s rule. A 15-mile long cast iron main was built from Marly-on-Seine to the palace and surrounding areas for the supply of water.

Interesting Fact: This system still functions after more than 300 years of service.

In the US, cast iron piping was imported from England and Scotland to supply water and gas to the larger cities of the Northeast. The first foundry that manufactured cast iron pipes in the US was established in Weymouth, New Jersey, in 1832; Pennsylvania and New York followed suit. By 1880, production spread to the Midwest and South.

During this time, cast iron pipes became the standard for water distribution, sewage, and stormwater systems because of improvements in casting and mold technology. This led to better-quality pipes with fewer defects, which still function today in many older cities.

But in the era between 1950 and 1975, new technology (ductile iron, PVC, PEX, and other plastics) emerged that replaced the use of cast iron pipes.

Different Types of Cast Iron Pipes

Several types of cast iron pipes are available, each for a different use:

Service Weight (SV) 

SV cast iron pipes are known for their durability and can be used in residential and commercial plumbing systems to handle normal waste and venting applications.

Extra Heavy (XH) 

Thicker than SV pipes, Extra Heavy cast iron pipes (XH) are suitable for applications that require additional strength, like high-rise buildings or areas with heavy traffic loads.

Hub and Spigot 

Hub and Spigot cast iron pipes have a bell-shaped (hub) end and a plain (spigot) end. The spigot end fits into the hub end of the adjacent pipe, and the joint is sealed with molten lead or a rubber gasket.

This traditional cast iron pipe is really tough and many property owners used it in older plumbing systems. Although less common today, you may still find it in many existing infrastructures.

Hubless (No-Hub) 

Hubless cast iron pipes, also known as No-Hub pipes, do not have the traditional bell-and-spigot ends. They are joined using stainless steel clamps and neoprene gaskets.

Not only this cast iron type is easier to install and maintain, but it also allows for more flexibility in tight spaces.