Close this search box.

How To Plumb A Single Bowl Kitchen Sink With Disposal

Note: This post may contain affiliate links. This means that at no cost to you, we may receive a small commission for made purchases.

Are you tired of cleaning leftover food from your kitchen sink?

If so, then you should consider installing a disposal unit in your home. 

How To Plumb A Single Bowl Kitchen Sink With Disposal

Garbage disposal units were first introduced in the 1930s and have remained a notable shortcut ever since.

The units are commonly used to break down food waste and flush it down the drain, thus removing it from the kitchen.

Nowadays, the benefits associated with disposal units have made them a popular choice among homeowners. 

However, one of the best things about these units is that they can be installed in almost any kind of kitchen sink (see also ‘What Are The Best Kitchen Sinks?‘).

So if you want to learn how to plumb a single bowl kitchen sink (see also ‘Why Does The Kitchen Sink Gurgle When The Toilet Is Flushed?‘) with a disposal unit, then you have come to the right place. 

What Are The Benefits Of Disposal Units? 

There are many people who would agree that every kitchen should come with a disposal unit, as they make cleaning your home much easier.

However, if you are still unsure about installing a garbage disposal, here are some benefits to consider: 

  • Easy Cleaning: Garbage disposals are mainly used to break down food waste and flush it down the drain, which comes with the added benefit of reducing blocked pipes and making cleaning up much easier.
  • Eco-Friendly Option: During use, disposal units are able to send more food waste down the pipes, which helps to reduce the number of food products being put in the trash for landfills. Because of this, garbage disposals are an eco-friendly alternative to throwing food in the bin. 
  • Reduces Rodents: Since garbage disposal reduces the amount of food waste in your home, it can also reduce the number of rats and other rodents entering your home and searching for food in the garbage. 
  • Cleaner Drains: Once the food has been broken down, it will cause less damage to the drains, which reduces the chances of blockages and repairs.
  • Reduces Food Waste: The addition of a disposal unit can also make cleaning the dishes faster and easier, while also reducing mess and food waste. 

Now that you understand the benefits of disposal units, it’s time to take a closer look at how you can install one in your home.

In most cases, these disposal units are compatible with almost every kind of kitchen sink, including single bowl alternatives. 

Can You Install A Disposal Unit In A Single Bowl Sink? 

The short and simple answer to this question is yes, you can install a disposal unit in a single bowl sink.

In fact, installing a garbage disposal in a single bowl sink is much easier than installing one in a double sink. 

However, this does not mean that the process does not come with its obstacles.

For example, you will need to make sure that you have enough space under the sink to install the pipes.

It is also important to have electrical wiring close at hand, as you will need this to activate the disposal unit.

In most cases, the on/off switch will need to be situated above or near the sink. 

Before you can start the installation process, you will also need to confirm that your sink is compatible with the disposal unit, as certain models are unsuitable for the modification.

For example, sinks with thick bodies may be too large to install the flanges, which means you will need to purchase an extended flange to make the unit work. 

How Much Does It Cost To Install A Disposal Unit? 

The cost of a disposal unit will often vary depending on the brand and model, as some units are more expensive than others. 

For example, a cheaper unit can cost around $85, while a more advanced model can cost up to $200.

You will also need to consider the cost of the installation, which can range between $80 – $200 depending on the person you hire.

In the end, you could be spending an average cost of $266. 

However, it is important to note that the installation process is much easier on a single bowl sink, which means you could be spending less money.

In fact, you could even consider installing the unit yourself using the methods outlined below.

So if you are interested in doing some DIY, let’s take a look at how you can install a disposal unit in a single bowl sink…

How To Plumb A Single Bowl Sink With A Disposal Unit 

How To Plumb A Single Bowl Kitchen Sink With Disposal

Before we can teach you how to install a disposal unit in a single bowl sink, you must first understand the tools and materials you will need to complete the job: 

  • Disposal unit (any brand or model)
  • Wire cutters 
  • Wire nuts
  • Electrical tester (non-contact)
  • Large pliers 
  • Putty knife 
  • Putty 
  • Screwdriver 
  • Hammer 
  • Utility knife 
  • Clean cloth or towel 

Once you have gathered all the necessary tools, you can start installing the new disposal unit.

In most cases, you should be able to install the unit on a single or double sink in less than 2 hours.

However, you will need the materials mentioned above to successfully complete the installation

To begin the installation process, just follow these steps: 

  1. Before you can start installing the unit, you will need to remove everything from the cabinet beneath the sink, as this will provide enough space to complete the task ahead. 
  1. You will also need to turn off the main circuit breaker (see also our guide on how to match wires size with circuit breaker), otherwise, you could risk serious harm to yourself during the wiring process. 
  1. Once these obstacles have been dealt with, you can use the electrical tester to confirm that there are no active wires beneath the sink. If the device comes up positive, then you will need to turn off all the breakers in the house until the power has been extinguished. 
  1. During this step, you will need to take the large pliers and disconnect the couplers securing the extension pipe under the sink. Once you have done this, set the drain to one side and use the cloth to plug up the drain line. This helps to reduce odors from entering the home. 
  1. Next, take the pliers and use them to unscrew the nut beneath the coupling. When it has been loosened, you should be able to move the coupling towards the main flange to separate it from the bottom of the sink. 
  1. Take the putty knife and use it to remove the leftover plumber’s putty from the drain. If you do not complete this step, it could become difficult to reattach the drain hole later on. 
  1. For the next step, take a small amount of plumber’s putty and rub it around the sink flange on the unit. Once you have done this, take the flange and insert it into the bottom hole of the sink, and then secure the gasket and backup ring. 
  1. After this, you will need to connect the mounting ring and secure it in place. This can be accomplished by tightening the screws until it’s flush with the drain. 
  1. Before moving on with the next steps, make sure to remove any excess putty from the main area using a clean cloth. 
  1. If you are installing a disposal unit and own a dishwasher, you will need to use a screwdriver or hammer to access the dishwasher knockout plug. This plug is commonly located on the side of the disposal unit.  
  1. To begin the wiring process, you will need to access the disposal unit’s electrical compartment and remove about 6-inches of cable from the on/off switch on the wall. Insert the cables into the main compartment and then use a screwdriver to secure the clamp. 
  1. Take the utility knife and use it to unsheathe the cables inside the main compartment, then use the wire cutters to remove half an inch of insulation from the white and black wires. 
  1. Take the wire nuts and use them to connect the white wires and the black wires together. Once you have done this, wrap the remaining wire around the grounding screw and secure it with a screwdriver. Make sure all the wires have been tucked away before closing the compartment. 
  1. Insert the discharge tube into the disposal unit’s outlet and then remove the towel from the drain. Following this, return the extension pipe and the trap before securing the couplers. 
  1. Connect your dishwasher to the drain line and tighten the coupler before switching the main breaker back on. If there is no immediate leaking or sounds, then the disposal should be ready to use. 

Can Disposal Units Back Up Into The Dishwasher? 

If you decide to connect the unit to your dishwasher, then some food waste may find its way into the latter.

To combat this problem, you can either pour boiling water down the drain to loosen the debris or call in a professional plumber.

If you choose the former, the water will need to be poured once a week. 

Final Thoughts 

Installing a disposal unit in a single bowl sink is a lot easier than it sounds.

All you need is the correct tools and the knowledge to get the job done.

Whenever approaching a task of this size, it is advisable to read the manufacturer’s guide for extra advice.

author avatar
Anthony Barnes
Anthony Barnes is the founder of Water Heater Hub and a second-generation plumber by profession. Before developing Water Heater Hub, Anthony Barnes was a full-time plumber, and he has undertaken a wide variety of projects over the decades. As a second-generation plumber, it was easy for Anthony to get used to the technicalities of all from a tender age


On Key

Related Posts

Is Drano Bad for Pipes? The Truth Revealed

Note: This post may contain affiliate links. This means that at no cost to you, we may receive a small commission for made purchases. When it comes to dealing with clogged drains, many homeowners turn