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Replacing a bathroom sink p-trap is a fairly simple process involving just a few very basic skills and some tools you probably already own.

If your sink clogs often, or smells funny, replacing the p-trap may just solve the problem.

It is an inexpensive way to fix a frequently clogging or smelly sink drain.

How to replace a P-trap – DIY Guide

Our guide will help you replace the p-trap by yourself, so make sure you follow our instructions and expert tips to do it quickly and easily!

Step 1

Open the cabinet doors and insert a bucket under the p-trap. If a bucket does not fit, use a small plastic container. This will prevent spills when the p-trap is removed.

Step 2

Unscrew the lock nut on the tail pipe side of the p-trap (the higher end of the p-trap). The drain tail pipe is the vertical piece of pipe extending up from the p-trap to the sink drain. Use a pair of slip joint pliers or a plumber’s wrench if necessary.

Step 3

Unscrew the other lock nut on the backside of the p-trap (the lower end), the nut connecting the p-trap to the drain pipe behind the sink. You can unscrew the lock nut below the 90 degree fitting, or the one on the straight piece of pipe leading to the drain outlet.

Step 4

Pull the p-trap down and off of the tail pipe, and turn it sideways and pull it out of the main drain line.

Step 5

Replace the washers and lock nuts. Slide the lock nut and washer off of the tail pipe and main drain lines, replace each with a new compression washer (bevel side down) and lock nut. This is important to create a water tight seal and prevent leaks from the p-trap.

Step 6

Slide the new p-trap onto the drain tail pipe, turn and push the back end of the p-trap into the drain line.

Step 7

Tighten the lock nuts by hand or use your pliers.

Step 8

Turn on the faucet and check for leaks. Tighten the lock nuts if leaks occur. If leaks persist, you may need to replace the lock nuts, compression washers or drain pipe.