How to Install PVC Bathroom Sink Drain Plumbing

PVC bathroom sink drain plumbing has become the common replacement for metal plumbing.

PVC bathroom sink drain plumbing is common and easy to work with.PVC bathroom sink drain plumbing is common and easy to work with.
PVC doesn't deteriorate over time, unlike metal drain pipes which will corrode, rust and eventually warrant replacement. Many drain pipe kits are available at hardware stores, and the pipes can be cut easily to size using a regular hacksaw. Even someone with limited do-it-yourself experience will be able to hook up PVC drain plumbing.

Measure the sink drain stem diameter with a tape measure. This is critical so that you can get the correct fitting PVC drain pipes.

Purchase a PVC sink drain plumbing kit that fits the diameter that you have previously measured. Although you can get single PVC pipes and piece them together, a kit will come with all needed pipes and washers, and it will be less expensive as well. Each kit comes with a tail piece that attaches to the sink drain stem, a middle P-trap pipe, and a drain pipe that attaches to the drain pipe inside of the wall.

Fit the 3 PVC pieces together. Attach the tail piece to the sink drain stem, attach one end of the P-trap to the tail piece and attach the other end of the P-trap to the PVC drain pipe. Insert the PVC drain pipe into the wall drain pipe to make a watertight sealed drain connection.

Measure the distance from the P-trap to the wall pipe and cut the tail piece to fit this distance using a hacksaw. Attach the tail piece onto the sink stem pipe leading directly down from the sink. Slide a nut and a compression washer, beveled side down, onto the sink stem, wrap the threads on the tailpiece with Teflon tape and hand screw them together.

Attach the tail piece onto the P-trap once they have been fitted properly. Slide a fitting nut onto the tail piece, then slide on a plastic compression washer, beveled side down. Wrap the threads on the P-trap with the Teflon tape, connect the P-trap to the tail piece and tighten the fitting nut using an adjustable pliers.

Place a fitting nut onto the back of the PVC drain pipe, then follow that with a washer. Slide the PVC drain pipe into the wall drain pipe and lightly tighten the fitting nut with your hands. The drain pipe must remain loose and adjustable at this point until the P-trap has been attached.

Place a compression washer into the PVC drain pipe side of the P-trap. The P-trap pipe will be the middle one of the three connecting pipes. Wrap the threads with Teflon tape. Slide a fitting nut onto the drain pipe and connect it up to the P-trap. Adjust the drain pipe as needed to make all the pipes fit seamlessly together.

Tighten down the fitting nuts with an adjustable pliers. Tighten the fitting together firmly, but do not over-tighten and strip the plastic threads.

Things You Will Need

  • Tape measure
  • Adjustable pliers
  • Teflon tape

Tip

  • Some drain pipe kits are designed with pre-attached hand-tighten fitting nuts. These kits are easier to use and do not require the use of an adjustable pliers to tighten the nuts. However, the threads still must be wrapped with Teflon tape, and the force needed to turn the nuts to provide a leak-proof seal may be excessive for some people to achieve by hand.

About the Author

Dale Yalanovsky has been writing professionally since 1978. He has been published in "Woman's Day," "New Home Journal" and on many do-it-yourself websites. He specializes in do-it-yourself projects, household and auto maintenance and property management. Yalanovsky also writes a bimonthly column that provides home improvement advice.