Choose the right pipe fittings to connect pieces of plumbing together


Pipe fittings help run pipe where you need it to go, including around corners, through ceilings or underground.

This guide will walk you through the types of pipe fitting materials, connection types, and common uses.

Materials and Connection Types

The material used for the pipe fitting is largely determined by its use.

Pipe fitting materials include:

  • Copper
  • PVC
  • ABS
  • PEX
  • CPVC
  • Brass
  • Black and galvanized steel malleable iron
  • Galvanized Steel
  • Polyethylene

Connection types

  • Sweat fittings: Use solder as a filler material.
  • Solvent weld fittings: Smoothed walled and connect using quick-drying solvent cement. May be male (smaller) or female (larger).
  • Push-to-connect fittings: Make installation quick and easy.
  • Threaded fittings: Female openings have threading on the inside of the fitting and close around male connections, which have thread on the outside.
  • Compression fittings: Use a threaded body, nut and ferrule to join pieces of pipe together.
  • Flare fittings: Use a flare nut and flare fitting to connect the pipe to the fitting after the pipe has been flared.
  • Crimp fittings: Use a ring tightened around pipe after the fitting has been inserted.
  • Clamp fittings: Use a clamp tightened around pipe after the fitting has been inserted.

See the chart for common fitting materials and the type of connectors used to join them.

Material Connection Type


  • Compression
  • Sweat

Black and Galvanized
Steel Malleable Iron

  • Threaded

Galvanized Steel

  • Threaded


  • Threaded
  • Sweat


  • Compression
  • Solvent weld


  • Crimp
  • Clamp


  • Clamp

Fittings for Residential Construction

Pressure (supply) fittings and drain-waste-vent fittings are the two major types of fittings used in residential construction.

Pressure fittings utilize pressure to maintain flow. Used above ground to connect the pipes that bring water to faucets and fixtures. Available in PVC, CPVC, PEX, polyethylene, brass, black and galvanized steel malleable iron and galvanized steel.

Refer to the chart to identify the supply fitting you need.

I Want to... Use This Fitting Types and Applications

Divert water to another line


  • Straight Tees have three openings of the same size
  • Reducing Tees have at least one opening smaller than the other

Change the direction of a pipeline


  • Standard Elbows have two ends that accept the same size pipe
  • Street Elbows have one end to accept pipe and another end that is the same size as the pipe
  • Reducing Elbows join one sized pipe to another
  • Drop Elbows have "wings" to attach to a wall

Join pipe end to end

Couplings and Adapters

  • Standard Couplings have female threads or open
    sockets at both ends
  • Reducer Couplings connect smaller pipes to larger ones
  • Adapter Couplings connect soldered or glued joints to threaded joints.

Connect or disconnect pipe in the middle of a line


  • Necessary for threaded pipes
  • Dielectic Unions transition from steel to copper, block electrolysis and prevent corrosion

Seal the end of a pipe


  • Fits over the end of a pipe
  • Can be used for incomplete jobs to restore water pressure

Seal a fitting with a plug


  • Fits inside a fitting

Connect one type of pipe to another


  • Connects pipes of different materials together, such as copper

Drain-waste-vent fittings use gravity to move used water and waste out of the home. The fitting you select determines the slope of the system. The general rule is ¼-inch per horizontal foot of pipe.

Refer to the chart to identify the fitting you need.

I Want to... Use This Fitting Types and Applications

Change the direction of flow


  • Elbows are available in 90°, 60°, 45° and 22 ½° turns

Connect a toilet to the main drain

Closet Flange

  • Fits into elbows including closet elbows and closet bends
  • Flange anchors to floor to

Join two lines together


  • Used to bring branch lines into a run
  • Wyes have a 45° angle to flow through the system

Be able to clear out clogs easily


  • Male plug connects into an adapter fitting
  • Should be placed in a convenient location for easy access

Prevent gases from coming into my home


  • Creates a seal by trapping water in the fitting's arc

Divert and remove water


  • Sanitary Tees have a directional sweep in the branch to direct water, waste and air
  • Long Turn Tee Wye have an extra long sweep to improve the removal of used or waste water
  • Vent Tees (and elbows) have abrupt 90° angles for fittings used only in the venting side of the system.

Flexible couplings are also an option. They are used to connect, adapt, reduce, plug or cap plumbing pipes. They are easy to install, and useful for in-house plumbing, sewer and drain applications