How to Install a Dual Kitchen Sink Drain

Dual kitchen sinks require a drain line from each side.

A dual kitchen sink gives options to wash dishes in one side of the sink and rinse them in the other side. Dual kitchen sinks have a water drain at the bottom of each side to drain them individually. The drain pipes route down from each where they join and then flow downward through a trap and then to the drain exit to the sewer system. The kits in this example are available at building supply companies and hardware stores. A kit has pre-cut PVC pieces so homeowners do not need to cut the pipes to fit.

Things You'll Need

• Dual sink drain kit
• P or S trap drain kit
• Pipe thread compound
• Adjustable pliers
• PVC primer
• PVC glue

Instructions

1. Turn both the hot and cold water supply valves off under the kitchen sink. Turn each knob clockwise to turn completely off.

2. Apply pipe thread compound on the metal threads of the sink drain basket in the cabinet underneath the kitchen sink and insert the drain tailpiece. Slide the metal drain basket nut over the tailpiece and tighten by turning clockwise with a pair of adjustable pliers. Follow this same procedure for the second sink drain basket.

3. Use PVC pipe primer in the inside of each female piece and on the outside of each male piece. Let it dry briefly and then apply PVC pipe glue in the same areas for each junction. Repeat this step for each junction when putting pipe together before tightening the plastic slip joints.

4. Attach the elbow beneath the tailpiece on one sink basket by putting the plastic slip joint on the tailpiece, sliding the elbow onto the slip joint and tightening the slip joint with adjustable pliers in a clockwise direction. Slide a plastic slip joint on the horizontal end of the elbow. Attach the T fitting underneath the second sink basket with a slip joint and hand tighten. The T opening should face the other sink. Attach the T opening with a plastic slip joint to the elbow and hand tighten. Fully tighten both the slip joint above the T and the slip joint leading to the elbow.

5. Attach the P or S trap kit with one end on the straight down piece of the T with a plastic slip joint and tighten. Place a plastic slip joint on the other end of the P or S trap and connect with a plastic slip nut to the drainpipe.

Tips & Warnings

• Drain pipes that drain down through the bottom of the kitchen cabinet use an S trap in the kitchen drain. Drainpipes that exit the kitchen cabinet horizontally through the cabinet wall use a P trap. Choose the trap that suits the draining method for the kitchen sink.

• Each drain basket includes a metal nut at the bottom of the basket included in their purchase.

• Slip joints provide areas at each pipe junction to detach easily by unscrewing the slip joint for maintaining and cleaning kitchen drains.

References

• Hammer Zone:Installing PVC Kitchen Sink Drain Plumbing