What is the function of a tee in plumbing? (Made in black, galvanized, copper, pvc, pex, etc)
A tee (or T-fitting) is a plumbing fitting shaped like the letter “T.”
Its main function is to:
- Join three pipes together
- Create a branch line from a main line
What a Tee Does
- Splits flow---A main pipe can branch off to feed another fixture or appliance.
- Combines flow---Two lines can merge into one line (depending on system design).
- Changes direction by 90°---The branch outlet typically comes off at a right angle.
Common Types of Tees
- Equal Tee – All three openings are the same size
- Reducing Tee – One outlet is smaller than the main run
- Sanitary Tee – Used in drain systems (designed for proper flow)
- Threaded Tee (FIP) – Used in gas or black iron systems
- Sweat / Press / PEX Tee – Used in copper or PEX systems
Simple Example
If you have a ¾" water line running across a basement and need to supply a ½" sink line, you would use a ¾" × ¾" × ½" reducing tee.
Where Tees Are Used
- Water supply lines
- Gas piping
- Hydronic heating
- Drain, waste & vent (DWV) systems
- Compressed air systems
In Plain English
A tee’s job is simple: It branches a pipe line off another pipe line.