A double sink drain ties two sinks together draining into one plumbing drain outlet. The part used for tieing the drains together is a "slip-joint end(or center) outlet waste drain". A end outlet waste drain ties the sinks together and the outlet is at either end of the drain. A "center outlet waste drain" the outlet is in the middle the two sinks.
The bathroom sinks drain, tail piece, and trap for bathroom sinks are 1-1/4" in diameter. For kitchen sinks the drain, tail piece, and trap are 1-1/2" in diameter. The tools required for installing a double sink drain are a pair of channel-lock pliers and some plumbers pipe dope.
There are two materials that plumbing drain traps and the other components are made of and these would be plastic and light gauge steel. I personally recommend using the steel traps and components because they come with rubber washers eliminating the need for the pipe dope between conections and they are more durable. If you use plastic or steel becareful not to over tighten the slip nuts.
Kitchen Sink Slip Joint End Outlet Waste Drain
Kitchen Double Sink Drain
Step1.
For the tail piece that connects to the basket strainers there is a special plastic washer that installs between the tail piece and the strainer, apply pipe dope to both sides of the plastic gasket and insert it into the tail piece. Install the tail pieces onto the basket strainers being careful not to over tighten the slip nut.
Step2.
Insert a slip nut with the threads facing down onto the tail piece, under the slip nut insert a plastic ferrule over the tail piece. Apply Pipe dope around the outer rim of the slip joint connection of the drain tee. Install the drain tee onto the tail piece that is closest to the drain outlet in the wall and hand tighten the slip nut.
Step3.
Insert a slip nut with the threads facing down onto the tail piece, under the slip nut insert a plastic ferrule over the tail piece. Apply Pipe dope around the outer rim of the slip joint connection of the drain tee and the drain arm slip joint connections. Install the connecting drain arm inserting in onto the remaining tail piece and into the drain tee and hand tighten the slip nuts. The connecting arm should slope downwards to the drain tee.
After making all the connections tighten the slip nuts with a pair of channel-lock pliers an additional 1/8 of a turn past hand tight. After reinstalling the trap, turn on the water and check around the drain and the trap for leaks. Some leaks are so small that it might take a few hours or a few days depending on the leak and how often the sink is used before the leak appears, for this i usully take a paper towel and leave under the drain. The next day if the paper towel shows drip spots there is a small leak which usully is not hard to find.
Bathroom Double Sink Drain
A bathroom double sink drain is similar to a kitchen double sink drain except all the connections will be a slip joint compression connection. The tools required for installing a double sink drain are a pair of channel-lock pliers and some plumbers pipe dope.
Step1.
Insert a slip nut over the tail piece with the threads facing down, insert a plastic ferrule onto the tail piece under the slip nut. Apply pipe dope around the outer rim of the slip joint connection of the drain tee and install the drain tee onto the tail piece closest to the drain outlet in the wall and hand tighten the slip nut.
Step2.
On the second sink insert a slip nut over the tail piece with the threads facing down, insert a plastic ferrule onto the tail piece under the slip nut. Apply Pipe dope around the outer rim of the slip joint connection of the drain tee and the drain arm slip joint connections. Install the connecting drain arm inserting in onto the remaining tail piece and into the drain tee and hand tighten the slip nuts. The connecting arm should slope downwards to the drain tee at a slight angle.
After making all the connections tighten the slip nuts with a pair of channel-lock pliers an additional 1/8 of a turn past hand tight. After reinstalling the trap, turn on the water and check around the drain and the trap for leaks. Some leaks are so small that it might take a few hours or a few days depending on the leak and how often the sink is used before the leak appears, for this i usully take a paper towel and leave under the drain. The next day if the paper towel shows drip spots there is a small leak which usully is not hard to find.
If you have a question about installing a kitchen double sink drain or a question about another repair post it in the user feedback.
