The Pros and Cons of Different Types of Plumbing Pipes

Since plumbing was first invented, the material used for piping has been an important factor. In the early days of plumbing in the ancient world, lead and clay piping was used to transport water to homes and public buildings. In the early twentieth century, when plumbing began to move into homes in the U.S., materials like cast iron, terra-cotta, copper and galvanized steel were used. Lead piping was also common and was the material of choice for plumbing pipes until World War II.

However, as the understanding of lead poisoning increased, the popularity of lead piping fell off, particularly for water that was meant to be potable. After World War II, galvanized screw piping gained favor as the material of choice for plumbing pipes inside the home, and a few decades later, in the 1970s, copper became more popular. Later in the 1970s, polybutylene was introduced. It was found that this material is compromised by exposure to chlorine, though, so many building codes now ban the material.

Today, there are many types of plumbing pipes available — some old classics and some made from newer materials. There are pros and cons you should consider with each of these materials when selecting which type of pipes to use in your home's plumbing system. In this post, we will discuss some of the popular options to choose from and the selling points as well as the drawbacks associated with each one. The integrity of your home's plumbing can play an important role in your quality of life, so you want to make a well-informed decision.

Main Plumbing Pipes

best types of drain pipe

There are five plumbing pipe materials that are — or were in the case of galvanized steel — most common: copper, galvanized steel, polyvinyl chloride (PVC), chlorinated polyvinyl chloride (CPVC) and cross-linked polyethylene (PEX).

1. Copper Pipes

Copper is one of the most traditional materials for plumbing pipes and remains a popular option today. There are two main types of copper pipes that can be used together to outfit a whole plumbing system:

Rigid Copper: Rigid, or hard, copper is used throughout a house or building for the water supply. The material can be cut into pieces and then soldered together.
Flexible Copper Tubing: Flexible, or soft, copper is malleable and is used in short runs where space is tight and flexibility is needed, such as in corners or in a supply line to your faucet.

Copper Pipe Sizing

Copper piping comes in different sizes, labeled by the diameter, in millimeters, from one outside edge to another. The most popular sizes are 15 mm and 22 mm, but you can also get 18 mm piping and many sizes above 22, all the way up to 108 mm.

The other way of measuring rigid copper piping has to do with its thickness. There are three grades of thickness to choose from for use in plumbing:

Type M: This type is the thinnest copper used in plumbing. It can usually be used for water piping, but it is more often used for drain, waste and vent (DWV) piping. This type works well for hot and cold supply lines in the home.
Type L: This medium thickness tends to be the type of choice for transporting drinking water. As with Type M, this type works well for interior hot and cold supply lines.
Type K: This type has the thickest walls, making it ideal for harsh conditions. Unlike Types M and L, Type K is the ideal choice for underground service lines.

Pros and Cons of Copper Pipes

Copper pipes have stood the test of time because of some important advantages they have, including:

Longevity: Copper has proven to be a reliable material that can last at least 50 years.
Durability: Copper is a sturdy material that is not prone to leakage or corrosion.
Safety: Bacteria cannot thrive in copper pipes, and copper will not pollute water in any way, so it is safe to transport drinking water.
Recyclability: When copper pipes eventually need to be replaced, the material can be recycled.
Temperature Tolerance: Copper is able to stand up to extreme temperature changes, including hot and cold water.

With so many strengths, you may wonder why copper is not used for plumbing in every case. Copper is not always chosen because it does have some cons compared to other materials. Disadvantages of copper pipes include:

Financial Cost: The main deterrent to using copper is the cost. The value of copper as a global commodity has gone up in recent years, so today, it will cost you approximately $285 for 100 feet of piping.
Environmental Cost: Environmentally-conscious homeowners may be concerned about the fact that copper mining and manufacturing take a toll on the environment. So, although copper pipes last a long time and can be recycled, they are not considered a "green" product.

2. Galvanized Steel Pipes

Galvanized piping used to be the material of choice for residential plumbing, and it is still what many people picture when they think of a plumbing pipe. The steel pipes are coated in a layer of zinc, which is meant to prevent rusting. The ends of pipes are threaded so they can be screwed in to each other.

These pipes are undoubtedly strong, but they are no longer used much at all. Galvanized pipes are still sometimes used to transport non-potable water, but it is too prone to problems to transport potable water safely. While homes today are very rarely outfitted with galvanized steel pipes, homes whose plumbing was installed in the 1980s or before may still have them. If this is the case in your home, you should consider replacing these pipes right away.

Cons of Galvanized Steel Pipes

Though galvanized steel pipes are cheaper than copper, are strong and manage to resist rust for a time, these pros are far outweighed by the cons, which include:

Short Lifespan: Galvanized steel pipes last about 20 to 50 years before they begin to break down. This lifespan may not seem too short, but it pales in comparison to the lifespans of many other piping materials.
Rust: Especially in pipes with a small diameter, rust can build up inside over time. In some cases, the rust can break loose from the inside walls of the pipe and end up mixing with the water as it flows through. This discolors the water.
Lead Contamination: If pipes become corroded, lead can leach into the water inside, making it unsafe to drink.
Clogs: Over time, mineral build-up inside of galvanized pipes can begin to form clogs that block water flow.
Weight: The downside to these pipes being very sturdy is that they are also extremely heavy. This makes them difficult to work with.
Vulnerability: When galvanized pipes are damaged, the galvanization on the outside is compromised, which makes the pipe vulnerable to corrosion in a short amount of time.

3. Polyvinyl Chloride Pipes

Polyvinyl chloride, more commonly known as PVC, has become a popular choice for plumbing pipes in recent years. This material is a thermoplastic polymer. In other words, it is made out of a combination of plastic and vinyl. PVC pipes are rigid and are usually white, cream or grey in color. They are used most often for highly pressurized water, such as in a home's main water supply line. PVC pipes work in a variety of applications, including for transporting potable water and for draining.

Depending on the application, you can choose a particular thickness and configuration designed to best support that application. If the piping is meant to transport drinking water, look for an "NSF-PW" or "NSF-61" label, which means the material meets the standards laid out by NSF/ANSI 61: Drinking Water System Components – Health Effects.

Pros and Cons of Polyvinyl Chloride Pipes

PVC pipes have gained popularity because of some important advantages they offer, including:

Longevity: PVC is not subject to rust or corrosion, so unless it experiences some sort of unexpected damage, it can last indefinitely. Even the most durable metals used in plumbing pipes cannot live up to the impressive lifespan of PVC.
Ability to Handle Pressure: PVC is often used for the main supply line that goes into your home because it is able to handle high water pressure.
Ease of Use: PVC is extremely light compared to metal pipes, which makes it easy to transport and to work with. It is also easy to work with because there is no soldering required to connect pipes. Instead, pipes are essentially glued together.
Low Cost: PVC is low in cost as well. Especially compared to copper, PVC is a very inexpensive option for plumbing pipes.

While PVC has some marked advantages, it has a couple of disadvantages, too. These include:

Susceptibility to Warping: PVC is not equipped to transport hot water. This is because, like most plastics, heat can cause the material to warp and melt.
Size: Sizing options for PVC pipes are limited, which can be an issue at times. Even if your PVC piping is the perfect size, fittings used to connect PVC pipes can tend to be bulky, which can be problematic in tight spaces.

4. Chlorinated Polyvinyl Chloride

Chlorinated Polyvinyl Chloride, shortened to CPVC, is closely related to PVC. Though both materials are made from the same basic elements, the key difference is that CPVC is chlorinated. This chemical difference makes CPVC able to withstand temperature differences in a way that PVC cannot. For this reason, some building codes call for CPVC in place of PVC for transporting hot water.

Whereas PVC is typically only available in a sizing system called Nominal Pipe Size (NPS), CPVC comes in this sizing system as well as in Copper Tubing Size (CTS). As the name suggests, this sizing system mimics the same size graduations used by copper piping.

Pros and Cons of Chlorinated Polyvinyl Chloride

CPVC pipes share many of the advantages of PVC, plus one more:

Longevity: Like PVC, since CPVC is a plastic material, it does not react to corrosive substances and does not rust, so its lifespan is indefinite.
Ability to Handle Pressure: CPVC shares PVC's ability to handle high water pressure, making it a good material for a main water supply line.
Ease of Use: CPVC is also quite lightweight, which makes it easy to move and work with. CPVC is also somewhat flexible.
Low Cost: Though CPVC costs more than PVC, it is still a budget option compared to metal piping materials.
Temperature Tolerance: CPVC is able to withstand extreme temperatures up to 200 degrees Fahrenheit. This equips CPVC to handle hot water transport.

CPVC does not have many clear disadvantages, though it may not always be the best choice. Cons include:

Indoor Application Only: CPVC is vulnerable to breaking down if exposed to sunlight for extended periods of time.
Cost Compared to PVC: Though cost was included as an advantage of CPVC, when comparing it directly to its close cousin, PVC, it does cost more.

5. Cross-Linked Polyethylene Pipes

Cross-Linked Polyethylene, or PEX for short, is another plastic material used for piping. Plastic pipes in general have become a popular type of pipe used in new homes. This particular plastic material is relatively new on the plumbing scene and can be used for a variety of plumbing applications. The major difference between PVC and PEX is that PEX pipes are flexible. This means they can be used in long, continuous runs.

In addition to being flexible, PEX is easy to cut and join together. The PEX system is designed to fit together with the combination of barbed fittings and crimping rings or cinch clamps. This method of joining pipes is in lieu of any soldering or gluing. The installation process is quick and easy, and the material is made to last. PEX piping can come coiled up in a flexible roll, wrapped in aluminum to keep its shape or in hard lengths.

Pros and Cons of Cross-Linked Polyethylene Pipes

To become the new favorite piping choice among many plumbers and homeowners, this material must come with some major advantages. These include:

Longevity: PEX pipes, like PVC and CPVC, are completely rust and corrosion resistant. This means they can last indefinitely without needing to be replaced, unless they are broken somehow.
Flexibility: PEX is flexible enough to make 90-degree turns with no problem. It can easily be snaked into walls — making it a great material for retrofitting — and it is able to extend across the length of a house with just one long piece.
Ease of Use: PEX's flexibility makes it very easy to install. When joints are needed, no soldering or even gluing is required.
Temperature Tolerance: Another important advantage of PEX over PVC is that PEX is able to withstand extreme temperatures. It can be used to transport hot water as well as cold.
Low Cost: Like CPVC, PEX is more expensive than PVC, but, at about $30 per 100 feet of piping, is still significantly cheaper than copper.

PEX does have a few disadvantages, though one of these PEX plumbing disadvantages has largely been debunked. PEX pipe problems include:

Indoor Application Only: PEX piping cannot be used in any outdoor applications since the plastic can be damaged by UV radiation. Of course, this is not really a disadvantage if you only plan to use PEX piping indoors.
Water Taste and Odor: Some types of PEX pipes have been known to affect the taste and odor of drinking water, especially if the water has stayed in the pipes for some time.
Possible Safety Concerns: There has been some concern and debate over whether PEX piping has the potential to contaminate drinking water due to the material's makeup. These concerns have largely been dispelled, however. Even the strictest environmental regulations in the U.S. now approve PEX piping, and research has shown that drinking water from PEX pipes does not involve health risks.

Additional Plumbing Pipes

Plumber working on kitchen sink plumbing with text: additional plumbing pipes

Now that we have looked at some of the most common types of plumbing pipes, let's take a quick look at several others that are not quite as common. These include stainless steel, cast iron, polybutylene (PB) and high-density polybutylene (HDPE). We will also briefly discuss another type of pipe that is not intended for plumbing: black iron.

1. Stainless Steel Pipes

Stainless steel piping is actually more expensive than copper piping. A high price point, however, indicates a high level of quality. Stainless steel pipes are strong and corrosion-resistant. Because of their ability to resist corrosion, stainless steel pipes are the preferable choice in areas that are susceptible to it, such as coastal communities.

Stainless steel piping is available in both flexible and rigid versions, and it comes in a variety of sizes. Pipes are fitted together using couplings.

2. Cast Iron Pipes

Cast iron used to be a common piping material for drainage systems, particularly in the first half of the twentieth century, and it can still be found in many homes today. Cast iron is extremely strong, durable and heavy. Cast iron also reduces sound and is heat-resistant.

Despite the advantages of strength and durability, though, a big disadvantage of cast iron is that it is susceptible to rust over time. In homes that have cast iron piping, if a pipe rusts all the way through, that section can be replaced with plastic piping, like PVC. Cast iron pipes come in various sizes, with the smallest usually being four inches.

3. Polybutylene Pipes

Polybutylene pipes, also referred to simply as PB pipes, were a popular choice for plumbing from the late 1970s to the mid-1990s. In fact, as many as 10 million homes built during that timeframe included polybutylene piping of some kind. Polybutylene is a type of plastic resin that was seen as a futuristic material, perfect for replacing copper.

These grey, plastic pipes were, and are, inexpensive and easy to work with. However, they fell out of favor because it was demonstrated that PB pipes were prone to leakage at the joints.

4. High-Density Polybutylene Pipes

High-Density Polybutylene pipes, also known as HDPE pipes, are one of the most popular choices for underground service lines, though they work in a variety of plumbing applications. This is due to HDPE's durability and ability to resist corrosion.

Some codes call for buried plastic lines to be made from HDPE instead of PVC. HDPE pipes are flexible, so they require minimal joints. Where they do require joints, heat fusion is used, making these pipes mostly leak-proof.

5. Black Iron Pipes

This type of piping is worth a mention, though it should be understood that it is not meant to be used in plumbing applications. Black iron pipes were at one time a popular piping material for water supply, but today, they are only used for conveying natural gas or propane. Black iron is also a popular choice for fire sprinkler systems since it is especially effective at resisting extreme heat.

Mr. Rooter Is Here to Help With All of Your Piping Needs

What type of piping is in your home? Especially in older homes, you may need to consider whether it is time to replace outdated or deteriorated pipes with better piping materials. Likewise, if you are building a new home, the type of piping you have installed is an important choice.

Whether you need to install a whole new plumbing system in your home or need some pipes replaced or repaired, you can trust Mr. Rooter Plumbing of Greater Syracuse to provide you with the best service possible. Our licensed plumbers will consult with you and answer any questions you have about the best pipes to use for plumbing or about your existing pipes. You can also request a job estimate online. In some cases, your pipes may have a lot of life left in them, but they might need to be cleaned out or unclogged. Our plumbers can take care of these issues, too. If you are not sure what sort of shape your plumbing is in, we are happy to offer a plumbing diagnosis and inspection.

At Mr. Rooter, we offer comprehensive plumbing services, including emergencies, so you can call us and get fast, courteous and efficient service, no matter what the issue is. Throughout the many years that we have provided the Syracuse community with piping and plumbing services, we have demonstrated a strong commitment to excellent customer service. We have the resources of a national chain with the compassion and care of a small-town business. Contact us today for all your piping and plumbing needs!

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