How To Plumb a Double Kitchen Sink With Disposal And Dishwasher?

There’s nothing worse than having to deal with food waste regularly if you’ve ever had to keep a kitchen clean.

When it comes to food waste removal, it doesn’t matter how old you are; it’s just plain filthy. However, if you want to keep your kitchen sink clear of clogs, you’ll need to address this issue.

So, are you sick of throwing away perfectly good food that was once part of a delicious meal?

When you overcook a dinner and have to clean the pans and pots afterward, it may be a real pain.

The installation of plumb a double kitchen sink with disposal or garbage disposal is the only solution to all of these issues. A combination of this and your sink is the most ideal solution in this case.

How to plumb a double kitchen sink with disposal and dishwasher?

Reasons to install a garbage disposal system

Most modern kitchens have a garbage disposal installed under the sink. In addition, if you don’t already have one installed, you should be aware of all the advantages of doing so today.

Garbage disposals may break up any food residue that accumulates in your sink and drain, allowing you to do the dishes more quickly and without as many clogs.

For those who care about the environment, this is a wonderful addition. You may reduce the amount of trash that ends up in landfills by breaking up more food waste and flushing it down the toilet.

More food goes down the garbage disposal, which means less food is thrown away. This implies fewer rodents and rats in your residence in metropolitan areas.

There is no need to worry about wildlife scavenging through your garbage in suburban areas because of the scent of food scraps.

It’s another fantastic benefit of having trash disposal under your kitchen sink to deal with the damage that big chunks of food waste may bring to your plumbing; consequently, there will be a decreased frequency of plumbing mishaps and repairs to do.

Can you plumb a double kitchen sink with disposal and dishwasher?

A double kitchen sink is more than capable of allowing you to add garbage disposal and a dishwasher unit if you so desire.

The first step is to make sure there is enough room under the sink for everything. Your dishwasher and disposal must also fit nicely in your sink’s pipes.

To connect your dishwasher and garbage disposal, you’ll need to make sure you have electrical wiring installed under your sink.

This wire should go to a wall switch on the opposite side of the sink, where you may turn on and off the disposal.

But keep in mind that some sink aren’t compatible with garbage disposal machines. There are a few of them out there, but it’s something to keep in mind. Especially with double kitchen sinks.

As an example, thick farmhouse sink may not fit conventional flanges because they are too thick. You’ll need an expanded flange to utilize them with garbage disposals.

Expenses of installing a garbage disposal

Be prepared to spend money on a range of items before installing disposal and dishwasher in a double kitchen sink. The garbage disposal unit is the first step.

The price will, of course, be greatly influenced by the model and brand you use. From $90 to more than $200, the price might vary greatly.

But you can save a lot of money by doing it yourself instead of hiring someone to do it for you. Installing the units with a reputable plumber who is confident in their work may cost you the same amount.

The installation and piping of this appliance are very straightforward, as you’ll see in our tutorial below, so there’s no reason why you can’t handle it on your own with a little effort and care.

If at any point you feel this to be too much for you, don’t hesitate to call in a professional.

How to install a garbage disposal on a double sink?

For the installation of this waste disposal device on a double sink, you’ll need a few things:

  • An old rag or piece of cloth
  • Non-contact voltage tester
  • Wire nuts
  • Wire strippers
  • Utility knife
  • A putty knife (plastic one)
  • Slip-joint pliers
  • Your garbage disposal unit
  • Hammer
  • Screwdriver
  • Plumber’s putty

Maintaining a clear and clean kitchen cupboard below the sink will allow you to work more freely on your double sink.

How to install a garbage disposal on a double sink?

Installation process of the garbage disposal on a double bowl sink drain

Turn off your disposal unit’s circuit breaker and inspect its wiring now before touching the double sink.

You need to make sure that the waste disposal’s wiring is completely insulated from electricity. Take a voltage tester and check to verify if the breaker has been properly shut off. If the tester still shows a light after that, electricity is still there, and you must turn off all the breakers one by one until the tester shows no power.

Your slip-joint pliers are needed. Afterward, use them to remove the couplers that connect the p-trap to the sink’s underside by loosening them. After that, make a safe location for all of the drain sections. If you don’t use the cloth to plug the drain, a bad scent is sure to spread throughout the kitchen.

To remove the drain coupling, you’ll need pliers. The drain flange can be separated from the lower part of the sink by pushing it up until it’s loose enough.

When the drain was first installed, the plumber’s putty was used to fill in the hole. Once you’ve removed all of the putties, use the putty knife to put everything back together.

Rub a small amount of the new putty onto the flange of the garbage disposal device and let it dry. Afterward, you can put this flange in the sink’s corresponding hole.

Snap the mounting ring into place as needed. After that, tighten all of the screws with the screwdriver so that the disposal unit is firmly in place next to the sink drain.


To remove excess plumber’s putty, use a rag to sink drain or a drain hose. A drain hose or drain pipe is a good option for drainage.

Just remember that there are a wide variety of garbage disposal models to choose from. If the unit has a different sort of fitting, the technique we’ve explained above may be different.

However, this is the most common path you’ll likely choose. You may also need to ensure proper drainage and a proper garbage disposal backing, if possible a new garbage disposal.

You can also examine the garbage disposal unit’s user handbook for extra information if you need it.

Garbage disposal discharging waste into the dishwasher drain line

Here are some of the most frequently asked concerns and problems about plumbing a double kitchen sink with garbage disposal and a dishwasher; now that we’ve outlined the process.

The most important of these is — what should you do if you discover that waste from your garbage disposal is backing up into your dishwasher drain line?

Because of the drain tube that connects the dishwasher to the garbage disposal, this may happen. To prevent water from running down your drain and into your dishwasher, make sure your garbage disposal drain line is free of debris.

Avoiding and resolving this problem is simple. The only thing you need to do is to flush the garbage disposal units with boiling water once a week.


Is it possible to connect the dishwasher and the garbage disposal to the same circuit?

Most people are aware that both the dishwasher and garbage disposal need 12/2 wires. For the garbage disposal and the washer, use a two-pole circuit breaker.
For personal safety considerations, you can quickly turn off either of them if they need to be fixed. A hose clamp may be used alternatively.

Is it possible to run the dishwasher and the garbage disposal at the same time?

Garbage disposal and dishwashers are frequently asked if they may be used at the same time. Keep in mind that both of these appliances use the same drainage system of pipes. As a result, if you utilize both at the same time, you may get plumbing issues with the disposal and dishwasher.
Before running your dishwasher, you should always check to see whether there are any food particles left in the disposal and dishwasher or drain hole.

Can your dishwasher double sink be affected by clogged garbage disposal?

Yes, especially if you recently installed waste disposal. The dishwasher drains into the same vent as the garbage disposal thanks to a rubber tube on the top.
A plastic plug on newer garbage disposals prevents the aperture for the dishwasher from being opened if you don’t remove it.
If you don’t do this, your dishwasher’s wastewater will be unable to exit and become trapped inside the appliance.

Final thought

This should clear out any gunk that has built up. To prevent clogs from ever occurring, we recommend doing this even if you don’t notice a clog.

Contact a reputable plumber if you’ve tried this and it hasn’t worked for you.

How to plumb a double kitchen sink with disposal and dishwasher?