What Is a P-Trap?
A P-Trap is a curved drain fitting that holds a small amount of water below a sink, shower, tub, or other fixture. The water blocks sewer gases from moving through the drain opening. The trap also connects the fixture drain to the building’s waste pipe and can collect small debris.
Quick Facts About P-Trap
Category
Drain plumbing component
Used for
Blocking sewer gases
Common confusion
Often mistaken for a drain strainer
Also called
U-Bend, plumbing trap
Often discussed with
Drain Cleaning
Key Takeaways About P-Trap
- Its curved shape holds water after the fixture drains.
- A removable section can provide access for drain cleaning.
- A P-Trap is not the same as a drain strainer.
How P-Trap Works
A P-Trap holds water in the low part of a curved drain fitting. Water from the fixture flows through the trap and continues into the waste pipe. After the flow stops, some water stays in the curve.
Related glossary terms: Cleanout, Drain Auger, Sewer Cleanout.
That standing water forms a seal against sewer gases. The trap also gives plumbers a service point when debris blocks a sink drain. A loose connection, damaged seal, or dry trap can allow odors or leaks.
Where P-Traps Are Used
Most plumbing fixtures with open drains use a P-Trap. Common examples include bathroom sinks, kitchen sinks, showers, and tubs. The trap connects to the fixture tailpiece and the drain line.
Expert Note
When we work on drain cleaning, we check the P-Trap for buildup, leaks, and loose connections. We may remove and clean the trap when the blockage sits near the fixture. We also check that the trap refills after the drain runs.
P-Trap in Practice: A Real-World Example
A bathroom sink drains slowly because hair and soap have collected inside its P-Trap. During drain cleaning, we inspect the trap and clear the nearby buildup before testing the sink flow.
Related Services
Related Terms
Cleanout
Cleanout is a capped access point in a drain or sewer pipe that lets a plumber…
Drain Auger
A drain auger is a flexible cable tool that clears clogs inside drain pipes. The cable…
Sewer Cleanout
A sewer cleanout is an access point in a drain or sewer line. The removable cap…
Toilet Flange
A Toilet Flange is a fitting that connects a toilet’s outlet to the drainpipe and anchors…
PlumbingKentwa.link
Have Questions About P-Trap?
Contact PlumbingKentwa.link for practical guidance on P-Trap and related plumber work in Kent.