How to Replace Kitchen Sink Drain Plumbing

What You'll Need
A kit including the drain trap and sink connectors
Piece of PVC pipe to connect to the bottom of the drain trap
Pipe glue
Pipe cleaner
Plumber's tape
Adjustable wrench
Pipe wrench - medium sized
A bucket
Connector sleeve to attach drain pipe to existing pipe
Light Sandpaper

Whether you have a leak or just want to replace your old pipes with new ones, choosing to replace kitchen sink drain pipes can be very scary. Most people have seen the funny skits on TV where someone works on the drain and ends up covered in yuck and water. However, the process is actually very simple. With a few basic tools and a long afternoon you can easily replace your kitchen drain pipes.

Step 1: Remove Existing Piping and Drain

Before you start cutting and removing pipe you will want to place a bucket under your sink drain. You should also tell everyone in the home that you are removing the drain pipes or you might want to shut off the water so no one floods your area.To begin the process you will want to remove the existing drain pipes. You can do this by cutting the pipe below the drain trap. Once this connection is severed you can easily unscrew the drains from the bottom of the sink and remove all the piping. When you cut the bottom pipe water will probably leak out into the bucket.

Step 2: Clean and Prepare Your Surfaces

Use the light sandpaper to remove any splinters or pieces of plastic left behind during the cutting process. The surface of the existing pipe need to be smooth and clear of debris for the gluing process. You will also want to remove any existing plumber's tape from the threads under the sink. In most cases you can use a cloth with light soap to wash the connecting areas and remove debris.

Inspect and Assemble Your Drain Kit

Most drain kits include an easy to follow process for completion. A basic kit will include two screw pieces that attach to the underside of the sink, an S shaped section made up of one to three pieces, and the gasket and screw tightener that attaches to the drain pipe. To be sure you have the drain pipe cut to the right size you will want to install the upper part of the drain first. Be sure to wrap each screw connection with plumbers tape before attaching the drain pieces to the bottom of the sink. Once you have assembled the S trap and affixed the two pipes to the under side of the sink you can measure the distance from the bottom of the S drain to the existing pipe.

Cut and Attach the Final Piece

The first thing you want to do is measure from the bottom of the S trap connection to the top of the existing drain pipe. Next you will want to subtract a half inch from this length. This is amount of space the connector will cover when you connect the new drain pipe to the existing drain pipe. Next, apply the pipe cleaner to the outside of the new drain pipe and the inside of the connector piece. Let the cleaner dry and apply the plumbers glue to the same surfaces. Once you apply the glue you will want to firmly push the connector on the new piece of drain pipe. Next repeat the process of cleaning and gluing the existing pipe to the other end of the connector.  At this point you have the bottom pipes attached and the top drain attached. The final step is to drop the screw piece from the S trap down over the edge of the new drain and tighten the connection. Check that all of the connection are thoroughly tight and allow the glue to dry before you start using the sink again.