How to Plumb a Kitchen Sink

plumbing a sink

You don't have to be an experienced plumber to learn how to plumb a kitchen sink.

Plumbing Jobs

Anyone who has ever hired a plumber to do even the smallest household job knows how expensive the job can be. In many cases, the service call actually costs more than the job itself, including supplies! Even if you are a handy do-it-yourself person in other areas of your home, you still may hesitate to dive into the world of plumbing. However, by following step by step instructions, you can learn how to plumb a kitchen sink.

Before You Begin

Whether you are building a new home or simply replacing the kitchen sink in your present house, you'll need to make a visit to your local home improvement store or plumbing supply shop. Selecting the sink is the first step to finishing the project. Take the time to read the box and maybe ask a store employee if you need any special tools or other supplies for the job. Points to consider include the following:

  • If you don't want any additional headaches, measure the old sink and choose a sink in the same size for a good fit.
  • For new installations, consider installing the faucets before fitting the sink into the countertop.
  • Be sure you have all of the supply lines, pipes, connectors, etc. before you begin the job.

Tools

The following is a general list of tools you'll need for this job. Keep in mind, however, that you may need additional equipment, particularly if you run into any problems. Also, some of the following equipment, such as supply lines, may be included with your sink. Be sure they are the right length, however.

  • Sink
  • Faucet (if necessary)
  • Drain kit
  • Pipes
  • Water supply lines
  • Pipe wrench
  • Plumber's tape
  • Plumber's putty
  • Light
  • Bucket

Cautions

  • It's always tempting to over-tighten drain line nuts. Avoid this temptation, however, as you could create additional problems, such as leaks.
  • Clean up as you go, so that any leaks are noticed immediately.
  • Use new rubber gaskets and nuts to ensure quality work and eliminate the need to troubleshoot for leaks later on.
  • Always check the gaskets and seals for cracks, and inspect the threads where the pipes will be placed. If you aren't sure about the threads, you can add plumber's tape for a tighter fit.

Steps for How to Plumb a Kitchen Sink

The following is a list of general steps on how to plumb a kitchen sink. While you can do this job yourself, you may want an extra pair of hands to hold flashlights, hand tools, etc.

  1. After you've removed everything from under the kitchen sink, be sure to turn off the water. You may be able to do this at the sink, or you may need to turn off the main water supply line.
  2. Disconnect the end of the main pipe out of the sink from the pipe that has a P-trap.
  3. Next, disconnect the main pipe from the sink, taking care to drain any water left in the pipe into a bucket.
  4. After you've removed the connecting nuts from the P-trap, pull the P-trap free, draining any excess water from the pipe.
  5. Remove the house drain pipe either from the wall or the floor.
  6. Remove the water lines.
  7. Now, it is time to install the new water lines.
  8. If you are installing a double sink, you'll have a "tee" section and two tailpieces. The plumbing kit you purchased should include all of the parts you need.
  9. Measure the tailpiece that fits with the house drain pipe to see if it fits. You may need to cut it if it's too long. For a double sink, you'll need to measure both sides.
  10. Attach the tee to the tailpiece with the provided connector, which should face the other sink. You should measure the elbow piece with the other drain to see if you need to cut it as well.
  11. You're now ready to attach the tailpiece and the long elbow pipe to the other sink's tee.
  12. You should attach the P-trap to the end of the tee, making sure it is facing the house drain pipe.
  13. Measure the pipe that connects the P-trap to the house drain pipe and cut to fit if necessary, then connect.
  14. Tighten all the nuts (but don't over-tighten!).
  15. Turn on the water supply, and check for leaks.

Finally, if leaks occur, go back and check the seals. You may need to add additional plumber's tape and/or plumber's putty for a tighter fit.

How to Plumb a Kitchen Sink