Home Improvement Skills & Specialties Plumbing

6 Different Types of Home Plumbing Pipes and How to Choose One

Main Types of Residential Plumbing Pipes

The Spruce / Michela Buttignol

Several types of home plumbing pipes are used to carry water to and away from fixtures and appliances. Whether you're hiring a plumber or taking on a DIY home plumbing project, the experience can be confusing because of all the pipe material options.

What is the right pipe for water supply, drainage, and sewer, for both interior and exterior? This guide breaks down common plumbing pipe materials such as PEX, copper, and ABS, to help you choose which is best for your space and application.

  • 01 of 06

    PEX Pipe

    Blue and red PEX pipes on gray wood floor

    The Spruce / Kevin Norris

    PEX (cross-linked polyethylene) is a durable plastic piping that's used to supply water. It is rigid enough to withstand the pressures of water supply but flexible enough to weave throughout walls, ceilings, basements, and crawlspaces. It is also far less expensive compared to many other piping materials.

    PEX pipes commonly come in 1/2-inch and 3/4-inch diameters, but they can be found in diameters up to 3 inches. PEX pipes are easy to cut and join. Plus, they're typically color-coded red for hot water and blue for cold water.

    Use for: Use PEX pipe as hot and cold water distribution lines within the house. PEX is also used to cycle reclaimed water; this pipe is marked purple to identify the type of water and distinguish it from potable water. Also use PEX for hydronic piping and distribution, such as for radiators.

    Tip

    Check your local codes before installing PEX pipe. While it is commonly used across the United States, it is not permitted everywhere. It must be well supported, and the fittings must be installed properly and tested, especially when installed behind walls.

  • 02 of 06

    PVC Pipe

    White PVC plumbing pipe on gray wood floor

    The Spruce / Kevin Norris

    PVC (polyvinyl chloride) pipe is a white plastic pipe material that's commonly used for waste lines. It initially gained popularity because it was lighter and easier to work with than traditional galvanized steel pipe. It's also inexpensive and fairly durable.

    PVC pipe is moderately easy to install and requires little more than a hacksaw and a miter box to cut. It glues together with solvents.

    Use for: PVC pipe and fittings are not rated for highly pressurized applications. Since building codes limit PVC pipe to drain, waste, and vent (DWV) applications, use PVC pipe for drainage and vent lines within the house. PVC pipe is commonly used for below-ground exterior irrigation water supply.

    Tip

    Like PEX pipe, PVC pipe is not permitted everywhere. So check your local regulations before installing.

    Best Ways to Repair a Leaky PVC Pipe

  • 03 of 06

    Rigid Copper Pipe

    Long and thin copper plumbing pipe on gray wood floor

    The Spruce / Kevin Norris

    Copper pipes are primarily pure copper as evidenced by their shiny reddish-brown appearance. Rigid copper is often used for water supply lines within the home. It is valued because it does not come with health risks unlike other pipe materials, such as plastics, that can leach chemicals.

    Rigid copper also is quite durable, and it can be cut easily with a tubing cutter or hacksaw. However, it is fairly expensive.

    Use for: Rigid copper pipe is routinely used for sinks, showers, tubs, and other fixtures. Though termed "rigid," rigid copper pipe can be bent to some degree. Inserting a spring in the pipe, filling it with sand or salt, or using a special tool are three ways to safely bend copper pipe.

    Tip

    Among the multiple options for connections, the best is the solder-type connection. The solder connection requires experience coupled with safety protocols.

  • 04 of 06

    ABS Pipe

    Black ABS plumbing pipe on gray wood floor

    The Spruce / Kevin Norris

    ABS (acrylonitrile butadiene styrene) pipe is made of a thermoplastic resin and looks very much like PVC pipe except it is black and slightly softer. It's mainly used as a vent and drain line.

    This pipe is fairly durable, though sun exposure can warp and degrade it, and it's a cost-effective choice. But like PVC, it isn't accepted by building codes everywhere, so check your local regulations.

    Use for: Use ABS pipe for both indoor or outdoor plumbing, but when it is used indoors restrict the pipe to drain, waste, and vent (DWV) applications.

    Continue to 5 of 6 below
  • 05 of 06

    Flexi Pipe or Braided Pipe

    Metal flexi plumbing pipe on gray wooden floor

    The Spruce / Kevin Norris

    Flexible pipe, often called flexi for short or braided pipe, is flexible tubing typically made of stainless steel. It's commonly used for final piping connections to appliances, such as water heaters, toilets, and sinks. It's generally not permitted for use inside walls or floors. 

    Flexi pipe comes in many lengths and sizes. It's somewhat durable, though it's not uncommon for it to fail after years of wear and tear. It also is expensive, though you typically don't need much of it for a project.

    Use for: Use flexible or braided pipe in exposed areas to connect water heaters, toilets, and sinks.

    Warning

    Do not use flexible pipe in enclosed applications, such as inside walls or floors. 

  • 06 of 06

    Galvanized Steel Pipe and Cast Iron

    Cast iron and galvanized steel plumbing pipes on gray wood floor

    The Spruce / Kevin Norris

    Two additional types of pipe are sometimes found in older homes and are infrequently installed, especially by DIYers: galvanized steel and cast iron pipe.

    Galvanized steel is rigid, corrosion-resistant steel piping that was used for decades for drainage, water supply, gas supply, and several other purposes. While galvanized steel pipe is still around (particularly for gas supply), it is far less common and not used for water supply in new construction or remodel projects. While it has good durability, it's also pricey to install. Each end of the pipe is threaded, and individual pipes are screwed into each other with connecting fittings.

    Cast iron is rigid, dark gray piping that was often used for sewer and other drainage purposes. It is still found in many homes and is used today in some commercial and high-rise building applications. Cast iron is expensive but durable with good longevity. It's viable until the point that it rusts completely through. It's also very heavy and difficult to cut. Retrofits tend to replace cast iron pipes with rigid plastic pipes, such as ABS.

    Use for: Use galvanized steel pipe for water supply lines, drain, and vent lines. For most homeowners, galvanized pipe will mainly be found in the form of gas supply lines. Though once commonly used for sinks, showers, tubs, and other fixtures, galvanized pipe still can be used in this manner, if local plumbing codes permit.

Choosing Plumbing Pipes

When choosing the right pipe for your plumbing job, the most important factors to consider are both the function the pipe needs to perform as well as the layout of the space you're working with. For instance, you might need a more flexible pipe for tight areas.

Cost also will be a factor in your decision. In general, a perk of more expensive piping is it tends to last longer. So ultimately you might save money in the long run. Plus, you'll have to know your local building codes to make sure you're using a permitted type of piping.

Speaking with a contractor or other plumbing expert can help you make an informed decision for your project. Sometimes you might not know exactly what you'll need until walls come down and you see the space you're working with.

FAQ
  • What is the most common pipe used in houses?

    Copper and PEX are the most common pipe materials used in homes. Copper pipes are durable, corrosion-resistant, and can be used for hot and cold water. PEX seems to be replacing copper pipes at a high rate since it is less expensive, more flexible, and easier to install.

  • What are the different types of water plumbing systems in a home?

    Plumbing piping is used for three primary reasons: toilet sewage, stormwater drainage, and drinking water. In each case, these systems bring and remove water into and from the home.

  • What is the safest type of pipe for drinking water?

    According to the Environmental Working Group, copper pipes with lead-free joint materials are the best choice for water pipes. They are long-lasting and won't leach chemicals into your drinking water. The group also cites polypropylene (PEX) pipes as a suitable alternative to copper that is less likely to leach chemicals into the water than other types of plastic piping.

The Spruce uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Plumbing and Pipes: Healthier Choices. Environmental Working Group.

  2. Plumbing and pipes. Environmental Working Group.