How to Clean Out the P-Trap on a Bathroom Sink

All sinks have a trap located under the counter.

A P-trap is a P-shaped bend in the drainpipe under your bathroom sink. When you run water down the drain, a small portion of the water stays in the P-trap. This keeps sewer gases from coming up the drainpipe and into your bathroom. Although a bathroom sink is not exposed to as much grease as a kitchen sink, you can expect a buildup of hair inside a bathroom P-trap. While you can use chemicals to clean the trap, they may damage the plumbing. Taking the trap apart is the best way to clean it.

Things You'll Need

• Bucket
• Wrench set
• Pipe wrench
• Needle-nose pliers
• Working sink
• Old toothbrush

Instructions

1. Place a small bucket below the P-trap under the sink to catch water that comes out as you loosen the pipe.

2. Look for a drain plug on the very bottom of the P-trap. Metal P-traps usually have a hex-head plug located on the bottom of the P-trap bend. It is possible for plastic P-traps to have a plug but it is not as common. Open the plug with a wrench to drain the water from the P-trap into the bucket. If you do not have a plug, forgo this step.

3. Loosen the compression nuts with a pipe wrench. The compression nuts are the knurled connectors located on each end of the P-trap. The top compression nut holds the P-trap onto the sink's downpipe, and the lower compression nut holds the P-trap onto the sewer drainpipe.

4. Pull the P-trap free from the plumbing and drain any remaining water into the bucket.

5. Pull out any clogs stuck in the P-trap using your fingers. For stubborn clogs, use a pair of needle-nose pliers.

6. Rinse the trap out with hot water; get water from a working sink, not the bathroom sink. Scrub the trap out with a small scrub brush or an old toothbrush.

7. Slide the lower compression nut over the sewer drainpipe, then slide the top compression nut over the sink's downpipe. Tighten each compression nut with the pipe wrench.

8. Secure the plug with a wrench if the P-trap is equipped with a plug.

References

• Ask the Builder: Cleaning P Traps, Tailpieces and Drain Lines; Tim Carter; July 2008
• Curbly: Bathroom Sink is Clogged Again? Replace That P-Trap!; Alex Russell; March 2005