14 Types Of Pipe Fittings

Pipe fittings are crucial components behind a healthy, efficient plumbing system. They are also your best bet to upgrade outdated pipe mappings without tearing everything out and restarting from scratch. Familiarize yourself with 14 of the most common types of pipe fittings so you know exactly what to use next time you divert, join, or redirect a line.

Tee

Tee fittings are the most common type of pipe fittings you will find. These are T-shaped components with one inlet and two outlets at 90-degree angles for splitting one supply line into two or joining two lines into one.

There are three types of tee fittings in the market. Regular tees, or equal tees, have the same diameter for all openings and are used to join the same-sized pipes. Unequal tees can be made with different diameters to join different sizes of branches. Finally, sanitary tees connect horizontal drains to vertical drains because they have a curved center section to allow more efficient liquid flow.

Wye

Wye fittings are used to connect multiple horizontal lines to reduce clogging and waste build-up. They can also be used to divide one line into multiple branches.

A standard wye fitting comes with three openings that either allow one line to be joined with another at a 45-degree or split one line into two sub-branches going in opposite directions. Meanwhile, a reducing wye, or “Y-bend,” comes with three female openings, two of which are straight and the same size, whereas the third bend is at a 45-degree angle with a different diameter. Therefore, reducing wyes are perfect for connecting a reducing branch line into a horizontal drain pipe going both directions.

Cross

As the name suggests, cross fittings have four openings with either one inlet and three outlets for splitting or three inlets and one outlet for joining. Cross fittings are available in brass, PVC, galvanized, and stainless steel. They are most commonly used in fire sprinklers or outdoor irrigation systems.

Elbow

Elbow fittings only have one inlet and one outlet. They are used to change a line’s direction to help it go around existing beams and structures. Elbow fittings come in 90, 60, 45, and 22.5-degree bends. You can join multiple elbow fittings to direct water supply around tight structures or use them individually at separate points to help a line turn. 

Coupling

Couplings, or pipe couplers, are slip-over tubes that go around the outside of two pipes to connect them together. Connections created by couplings are often permanent. Therefore, they’re most suitable in areas you won’t access once the pipes are done, such as in walls and ceilings.

There are two types of couplings: full couplings and half couplings.

Full couplings have two hubs connected by a central sleeve. They can transmit more torque than half couplings but require ample room for the entire pipe length to fit within the fittings. Meanwhile, half couplings only have one hub and are much easier to install or remove. They also work better in smaller, more compact spaces.

Adaptor

Adaptors are another great type of pipe fitting for connecting two pipes together and are often used to connect pipes in different diameters. Adaptor sizes range from 1/8” to 2”, with threads following National Pipe Thread (NPT). There are two types of adaptors: male and female adaptors and the male threads are often protected by a plastic cap. 

Bushing

Bushings, or reducer bushings, are a type of pipe fitting made to connect pipes of different sizes. The larger end (male end) of a bushing is inserted into the larger pipe, and the smaller pipe is inserted into the bushing’s smaller end (female end). Common bushing materials include brass, bronze, steel, stainless steel, and PVC.

Union

Similar to couplings, union fittings connect two pipes of the same size together. However, connections created by unions are not permanent. They can be adjusted as the two hubs are connected by a nut or threaded ring in the middle, making removal much easier than coupling connections. Therefore, union fittings are more suitable in areas you may need to access and adjust regularly. 

Nipple

Nipple fittings are a relative to coupling fittings. Instead of going around the outside of two pipes, nipples are designed with two male ends to connect two female-threaded pipes. Nipple is one of the most popular types of pipe fittings for straight pipe connections. 

Trap

Trap fittings are only used under a sink. They are horizontal dips or bends in a “U” or sideways “P” shape. Trap fittings catch debris and waste from your drain to prevent clogging farther down the system. They also prevent sewer gas from entering your home by using the water trapped in the curve as a barrier. Most trap fittings nowadays are made with PVC.

Flange

Flange fittings use bolts and clamps to create a tight seal around pipes when they pass through walls, ceilings, or floors. The most common types of flange fittings include:

• Welding Neck Flange

• Slip-on Flange

• Socket Weld Flange

• Lap Joint Flange

• Threaded Flange

• Blind Flange

Most flange fittings in modern homes are made with forged carbon steel, cast iron, aluminum, brass, or high-pressure steel.

Valves

Valve fittings are simple handle mechanisms that open or shut a supply line. Most residential plumbing systems have one central shut-off valve and multiple sub-valves. Valve fittings are separated into isolation, regulation, safety relief, and non-return valves. Most of them use a threaded or flanged connection, but some might require welding during installation.

Valves are crucial to your plumbing system and having them properly installed throughout the house can save your plumbing in the case of frozen pipes or major leaks.

End Connections

End connections are a special pipe fitting category designed to terminate the line instead of extending or redirecting it.

The two most common types of end connections are caps and plugs. Cap fittings are female-threaded and fit over the end of a pipe. These can be used to permanently or temporarily stop water or gas. Meanwhile, plugs are male-threaded and must be screwed into a pipe to terminate the flow.

Caps and plugs are essential to having a healthy, working plumbing system because they prevent dirt, dust, debris, and other contaminants from entering the line. 

Types of Pipe Fitting by Materials

The golden rule of choosing the right types of pipe fitting is always to use the same material as your pipes. For example, if you need to fix a leaking copper pipe, you will want to use copper pipe fittings after removing the chunk of the pipe. Pipe fittings in the market are often made with copper, PVC, brass, or galvanized.

DIY vs. Hiring a Pro

Joining pipes using a fitting is a simple project that can be done independently. However, consider hiring a local plumber if you need to cut out a portion of an existing pipe, put new pipes into the walls, or join multiple existing lines into one. On average, it will cost you $200 to $330 to fix a leaking faucet or a leaking pipe behind a wall. This price increases to about $500 if kitchen cabinets block the pipe.