Plumbing Pipes

The Three Common Types of Plumbing Pipes for Home Use

Plumbing pipes help supply water and natural gas to residential areas and carry off waste materials from these same houses. These pipelines may also serve as water channels to irrigation and drainage systems outside your home. But with all the types of piping materials sold in the market such as those found at The Home Depot and Lowes, homeowners often hit a blind alley in choosing the best plumbing pipes for their needs.

This guide introduces you to the world of pipe systems, provides basic knowledge of its installation, and offers a sneak preview on the three common types of plumbing pipes for home use. By the end of this reading material, you will gain a good understanding on piping materials in general and determine the right one for your next project.

Get Ready

The United States government requires each homeowner to consult building codes and ordinances in their local areas before they can replace an old pipe with a new one. Some U.S. cities strictly require professional services for pipe installation, and other local governments regulate the type of materials needed for a specific piping system.

Oftentimes securing a permit is not required for repair or simple pipe replacement, but you will need it for running pipe in a different location. Make sure you comply with the requirements of the local building inspection department before taking a step further.

Identify The Types of Plumbing Pipes

After the paperwork, you have to determine the type of plumbing pipe according to function: water supply, waste outlet, or gas supply. Water supply lines carry water, or sometimes other liquids, from a source to fixtures such as faucets and showers. Drain-Waste-Vent lines, or DWVs, carry waste materials, such as used water and gas, away from residential areas. Gas supply lines channel gas from a source to appliances such as ovens.

faucet fixture
Faucet in the sink. Featured image by Dennis Hamilton / Flickr (CC)

Choose The Piping Material

If you already have ascertained the use of the pipe, it’s time to choose the right piping material. Plumbing pipes are made of plastic or metal, and each type serves a specific purpose.

Water Supply Lines

a. CPVC – Chlorinated Polyvinyl Chloride. Mainly used for hot and cold water fixtures. It is often preferred over copper pipe in interiors.

b. PEX – Cross-linked Polyethylene. Mainly used for hot and cold water interior pipes in homes. It is easy to steer and evade obstructions, even without an elbow.

pex pipe
A PEX pipe. Featured image by Joshin Yamada / Flickr (CC)

c. PVC – Polyvinyl Chloride. Used only for cold water fixtures. It is also used for irrigation systems.

pvc pipe
PVC pipes for cold and hot water supply. Featured image by Jeremy Noble / Flickr (CC)

d. Copper – Used for hot and cold water applications in residences. It is lightweight, durable, and easily fits through tight places.

copper pipe
A rusty copper pipe. Featured image by Patrick Finnegan / Flickr (CC)

Drain-Waste-Vent (DWV) Lines

a. PVC – DWV pipes of this type are 1.5 inches or larger in diameter, while water supply pipes measure 0.5 to 2 inches.

b. ABS – Acrylonitrile-Butadiene-Styrene. Used in mobile homes, commercial and residential sanitary systems. It is light but strong and easy to cut.

ABS pipe
A 2-inch ABS pipe with Quagga Mussels. Featured image by Dan Bennett / Flickr (CC)

c. Cast Iron – Easily joins to plastic pipe with transition fittings. It is strong and durable.

cast iron pipe
A cast-iron pipe painted yellow. Featured image by ntcrwler / Flickr (CC)

Gas Supply Lines

a. Black Malleable – Black, malleable, galvanized iron or cast iron. Used to carry natural and propane gas from a source, such as the street or a tank, to the home.

b. Copper – Used to transport gas and indoor gas distribution. It is not recommended for natural gas in some areas, because its sulfur content may peel off the interior.

c. PVC – Used as main gas supply to homes. It is used only for underground applications and may come with wires that metal detectors can detect for repairs.

d. Polyethylene – Easily installs with minimal joints. It is durable and offers long resistance to the environment.

high density polyethylene pipe
High Density Polyethylene pipes. Featured image by Emilian Robert Vicol / Flickr (CC)

Know The Common Pipe Sizes

Plumbing pipes come in several sizing standards. The most common are cast iron soil pipe, copper tube size (CTS), sewer main or sewer and drain, schedule 40, schedule 80, and Standard Dimensional Ratio (SDR).

You have to know the exact dimensions of the pipe you need. Remember to check the local code requirements and verify if the materials you picked meet the standards.

Make The Job Easier

Plumbing is not an easy task for do-it-yourself, or DIY, warriors. It is always convenient to have handy tools that will lessen the load for you.

A tube cutter makes short work of plastic pipe, while a cast-iron cutter easily cuts through cast-iron pipe.

tube cutter
A telescopic tube cutter. Featured image by Emilian Robert Vicol / Flickr (CC)

You have to support a horizontal pipe every 4 to 6 feet with a hanger. Hangers include copper two-hole straps, plastic hangers, plumber’s straps, and wire hooks.

Dubbed as a muffler because of its noise reduction property, a water hammer arrestor dampens the banging of valves on appliances such as dishwashers, faucets and washing machines. It also prevents damage to faucets and pipes.

A vent filters the gas that runs out of pipes and provides air to aid the flow of water, while a trap, the one you find below the sink, keeps harmful gases outside of the house.

sink trap
A newly installed sink trap. Featured image by Stephen Pierzchala / Flickr (CC)

Use a cap to temporarily seal the end of a pipe against leakage and turn the water back on.

Just Do It

By now you have a basic understanding of how plumbing pipes work. And when dealing with piping systems, never forget to check the local code and regulations for standard requirements.