Looking at the pipes in your home is very different from actually knowing what they carry, what they are made of, and whether they need to be replaced. Some pipes are designed specifically to carry gas, while others carry potable water, wastewater, or even sewage gases.
You can find pipes made of copper, steel, iron, and plastic, each of which has different advantages and disadvantages, as well as certain limitations that can make them more or less effective depending on the job. Whether you plan to do work around the house or want to know how to identify the different types of plumbing pipes in your home in case of an emergency, this guide can help. Learn the pros and cons of common pipe materials and the best pipes to use for plumbing.
Common household plumbing pipes
Materials used in residential and commercial buildings are constantly being studied, so there are some variations in water pipes for home construction depending on the year the house was built, the safety of the material, and the purpose of the piping. Below are the most common household plumbing pipes, including: PEX pipeCopper, PVC, and more.
1. PVC pipe
Polyvinyl chloride, or PVC, is a type of plastic pipe commonly used to collect and redirect the flow of wastewater and sewer gases in both residential and commercial buildings. “These are the most common and commonly thought of when people think of plumbing pipes. They are commonly used for both sewer and wastewater lines,” explains Travis Hargrave, plumber and owner. Hargrave’s Plumbing.
PVC pipes are strong, durable and relatively inexpensive. They can be used indoors, outdoors and even underground. Their versatility makes them an option for home builders and plumbing professionals, although it should be noted that they are not suitable for high temperatures. To connect the PVC pipe, you need Cut the pipeApply primer, apply cement and then make a fitting slot on the end of the cut that is the right size, essentially joining the pieces together.
Best for: Gravity-fed drain, waste and vent (DWV) systems and below-ground external irrigation.
2. PEX pipe
PEX, or cross-linked polyethylene, another type of plastic pipe, is primarily used to carry hot and cold water throughout the home. “It’s the most common water pipe installed in new homes these days,” notes Hargrave. “Typically, the pipes are colored blue or red to indicate hot or cold. This piping is joined using compression rings, but a specific tool is required to compress the rings.”
Whether to use PEX Vs. Copper Pipe is a common question. PEX’s flexibility and color-coded design make it a great choice for water supply lines, although it lacks the durability and longevity of copper. There are three main types of PEX, named A, B and C. PEX-A is the most flexible, but the least durable; PEX-B has average flexibility and durability; And PEX-C is tough, but good for quick repairs. However, it is important to note PEX is susceptible to rodentsSo if you have frequent problems with mice, rats or other rodents, it may be better to go with copper or even CPVC pipe.
Best for: Indoor hot and cold water distribution lines.
3. Copper pipe
Easily the most widely used pipe for residential and commercial water supply, copper pipes are durable, long-lasting and resistant to corrosion and can be used with both hot and cold water. Hargrave mentions that copper pipe “is most commonly used as water piping, but is rarely used as drain pipe despite its corrosion-resistant material and longevity.”
There are many different types Piping made with copperIncluding rigid and flexible varieties, as well as copper with different wall thicknesses. However, copper is one of the more expensive pipe materials, and must be soldered together or joined with compression fittings. If you don’t have experience working with copper pipe, you may need to hire a plumbing pro.
Best for: It is best used for main water supply lines, bathroom and kitchen fixtures and exposed pipework.
4. ABS pipe
Acrylonitrile butadiene styrene, or ABS, is a common type of black plastic drain pipe that was once widely used as a replacement for PVC pipe. Hargrave states that ABS “is not universally banned, but some states, such as California, do not allow it because of batch problems in the 80s. Also, it has difficulty with high temperatures and exposure to sunlight, so it is used primarily on gutters in homes.”
This hard black plastic pipe is extremely durable and impact-resistant. It can withstand cold temperatures, and it is relatively expensive. You join pieces of ABS the same way you join PVC pipe: by cutting the pieces, applying primer, applying pipe cement, and then slotting the pieces together. Because this pipe is prone to fading in sunlight, it is best used underground.
Best for: Where permitted, it is best used for indoor and outdoor drain, waste and vent (DWV) lines.
5. CPVC pipe
Similar to PVC but designed for a different use, CPVC, or chlorinated polyvinyl chloride, is stiffer and more durable than PVC pipe. It is also resistant to high temperatures, allowing it to safely distribute hot and cold water throughout the home without worrying about it breaking or mixing with water. Since it is cheaper than copper, it can be a great option for your home.
While learning about DIY plumbingIt is important to understand that different types of pipes have different purposes. PVC is the standard for drain, waste and vent systems, and while CPVC can technically be used for corrosive wastewater and industrial fluids in specialized chemical applications, it is generally used for fresh, potable water, not waste.
Best for: It is best used for indoor hot and cold water distribution lines, especially in areas where local codes allow it as an alternative to copper.
6. Galvanized steel pipe
Galvanized steel is one of the many types of water pipes that are no longer used in new construction. These heavy, highly durable metal pipes fell out of use when it was discovered that the internal zinc coating tended to corrode over time, causing the steel to corrode, seriously damaging the pipe’s structure and function.
Degradation of steel can release harmful contaminants into drinking water, and, due to the weakening of the pipe, galvanized steel water lines are more prone to leaks or ruptures when system pressure changes, such as turning the water off and back on at the main shut-off valve. Hargrave notes that galvanized steel pipe is “common as a water pipe in old houses, but is now mostly used on gas.”
Best for: Galvanized steel used to be used for water lines, although it is now rarely used for anything other than gas lines.
Other types of plumbing pipes
In addition to the common plumbing pipes listed above, there are many other types that you may see or hear about. However, these plumbing pipes are either not widely used or may have very specific uses, such as the use of stainless steel in coastal cities or the use of high-density polybutylene for underground plumbing.
1. Cast-iron pipe
Cast-iron pipe is no longer used in residential plumbing, as is galvanized pipe. “Common in older homes and large commercial buildings, it is heavy duty and durable. Older homes often had lead joints to lock these together. Cast iron was also used as sewer pipe in the past,” explains Hargrave.
Cast iron’s heat-resistance, high durability and sound-muffling qualities once made it a popular choice for water lines and sewer lines, but it is susceptible to rust and corrosion, which eats through pipes, causing leaks. If cast iron is used for water lines, this corrosion can also leach into the water. Due to these dangers, cast iron is no longer used for piping, although it can still be found in some older homes.
Best for: Used for sewer, waste and vent (DWV) lines and main sewer stacks in older homes or commercial buildings.
2. Polybutylene pipe
For a short time between the 1970s and 1990s, residential plumbing used polybutylene pipe for hot and cold water lines. However, this plastic pipe was prone to internal deterioration, causing leaks, sudden ruptures and flooding, which led to production ceasing in 1996.
In fact, the durability and longevity of this type of pipe was so incredible that it actually took some time for PEX piping, a different type of plastic water line pipe, to overcome the poor impression of plastic pipe left by polybutylene. If your home still has polybutylene pipes, they should be replaced as soon as possible.
Best for: Not recommended for use and has been widely discontinued as it deteriorates, becomes brittle and prone to sudden leaks.
3. High-density polyethylene pipe
Developed in the 1950s, high density polyethylene (HDPE) pipe is still widely used today. However, it is sensitive to high temperatures, which can cause it to crack or even melt, so it is mainly used underground. This type of pipe is flexible and able to hold up well in cold weather, which is why it is commonly used to run water main service lines and underground municipal plumbing.
Best for: It is best used for underground plumbing, such as main water service lines from the street to the house, as well as municipal piping.
4. Stainless steel pipe
You won’t find stainless steel plumbing lines in most homes, but for those near the coast, stainless steel is the go-to option due to the material’s high resistance to corrosion, which keeps pipes in good condition even in salty air. Since stainless steel pipes are one of the most expensive types of plumbing pipes, they are rarely used throughout the home.
Best for: Stainless steel is best used in commercial, industrial and coastal applications where the water is highly corrosive.
5. Black iron pipe
At one time, black iron pipe was used for water supply piping, but as it was not coated and corroded easily when exposed to water, it was quickly replaced with more suitable alternatives such as copper. However, since this type of pipe is strong, durable and able to withstand high temperatures, it was useful for natural gas and propane systems. Hargrave notes that black iron pipe is now only used as gas piping: “In general, it’s cheaper than galvanized pipe, which is why contractors often use it when installing new gas lines.”
Best for: Black iron is now used especially for natural gas and propane distribution lines.
Final thoughts
Learning about the types of plumbing pipes helps prevent costly water damage and ensures code compliance. If you live in an older home, understanding the different types of pipes can also help you identify dangerous or outdated materials in your home that may need immediate replacement. DIYers who are familiar with plumbing pipes can tackle basic upgrades and repairs, such as fixing leaks or replacing fixtures, with confidence in knowing which tools and fittings to buy and without hiring a plumber.
Meet the tools of the year 2025
