How to Install a Garbage Disposal for the First Time

Last updated on November 20th, 2023 at 12:06 pm

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All modern kitchens have garbage disposals nowadays, even if you make sure all your dishes, plates, pots and pans are completely clean, there is still a certain amount of food waste that will end up going down the drain. Having a garbage disposal system in the kitchen means that it will be able to grind up the wasted food and will keep the pipes in your kitchen running smoothly.

If you have been thinking about upgrading your older garbage disposal system or installing a completely new one, the details mentioned below will surely help and guide you. While a typical garbage disposal system lasts about twelve years at least, it is a feature that will eventually need replacement.

What Do We Mean by Garbage Disposal?

A garbage disposal unit which is also known as waste disposal, garbage disposer and sometimes even garburator, is a form of device that is powered electronically and installed underneath the sink in the kitchen between the trap and the sink’s drain.

Installing or Replacing an Older Garbage Disposal Unit

Whether you want to replace or install a brand-new garbage disposal, it is not a difficult task that would require any special skills. In fact, if you are replacing an old garbage disposal unit with a new but similar model, the task becomes quite easy. You may just have to simply remove the older unit and install the new one with minimum steps.

Even if you are replacing it with a completely new model that is significantly different or installing a brand-new garbage disposal unit for the very first time ever, the task is quite easy. You must make sure, however, to check the dimensions for installation to be sure it will be able to fit in the space that is available.

When you are installing the garbage disposal system for the very first time, you should know that there are some plumbing and wiring skills that are necessary. You can hire a professional for these tasks if you are not comfortable or confident with your plumbing skills.

For instance, most of the recent building codes would require a dedicated 120-volt and 20-amp outlet under the sink and close to the garbage disposal unit. The outlet, however, should be controlled through a switch, which should be easily accessible to the users at the sink. While there is a likelihood of the circuit being present in your kitchen, if it is not, you would need to get it done yourself so that you can install the garbage disposal. If your plumbing skills are not up to the task, hiring a professional would be a much more convenient and safer route.

Do You Need a Garbage Disposal?

You must be sure you even need a garbage disposal system before you decide to replace an old unit. When garbage disposals were first introduced, people considered them something more of a luxury than a need. With the passage of time and with garbage disposals becoming more common in kitchens, people now assume automatically that all kitchens need one.

There is, however, a movement to remove garbage disposers from kitchens, popularized by environmentalists. There is a considerable strain on waste treatment facilities due to the garbage dumped into the sewer systems via the sink drains in the kitchen. As a result, many communities have outlawed garbage disposal systems in household kitchens. Many environmentalists even suggest it is better to throw away organic waste with the normal trash instead of grounding them and flushing them down the sink.

Plus, garbage disposal systems are not a wise decision if you are living in a rural area where the wastewater is processed through a drain field and septic system.

However, if you are completely sure that you do require a garbage disposal system for your kitchen, the steps below will help you install the system easily in your kitchen.

What Type of Garbage Disposal Would You Need?

When you are buying a new garbage disposal unit, there are certain factors which you must keep in mind. You must consider who will be using the garbage disposal system and what kind of plumbing facilities you have in your home. You will also need to decide between a noisy or noise-free garbage disposal system.

  • If there are children who would be using the garbage disposal system, you should get the batch-feed disposal system rather than the continuous-feed one. While the batch-feed disposal is more expensive, it is safer in a household with kids. The continuous-feed disposal keeps on running until someone shuts it off and in case someone drops a kitchen utensil in the sink by mistake or sticks their hand inside the sink, it can be quite a dangerous situation.
  • Choosing the right type of motor is also important. The bigger your household, the more horsepower you would require from the motor. Typically, a motor with 1/2 horsepower is good for bigger households, while a motor with 1/3 horsepower is good enough for smaller families.
  • You should consider the features which are important for you to have in your garbage disposal system. At a higher price, you can get a noise-free garbage disposal unit, one made with stainless steel or one that is connected to your dishwasher.

Materials and Tools You Will Need

  • A new garbage disposal unit
  • Channel-type pliers
  • Plumber’s putty
  • Screwdrivers
  • Electrical Cord
  • Hammer
  • Plug-in power cord
  • Garbage disposal mounting ring and drain fitting
  • Safety supplies such as goggles or a dust mask

How to Installing a Garbage Disposal System For The First Time
How to Install a Garbage Disposal for the First Time

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  1. Wire It

Some garbage disposal appliances come with the wires attached, while in others, they are not. If the wires are not attached in your unit, you must remove the cover plate beneath the garbage disposal system and attach them as per the instructions on the box. With most garbage disposal units, the user is required to attach the white wires to the white leads and black wires to the black leads. When you are finished with this, make sure you screw the cover plate back on.

  1. Install the Mounting Ring and the Drain Flange

First, you should roll the plumber’s putty between the hands so that you are able to form a snake that is about 1/2 inches in thickness and around 10 inches in length. Then, you must apply it on the underside of the drain flange that is underneath the sink and then insert the flange into the drain hole and push it down so that it gets attached. Then, you should snap on the fiber gasket, backup ring and mounting ring.

When you are working underneath the sink, you should use the screwdriver in order to tightly screw the mounting ring against the sink. You can make the process more efficient by alternating sides by screwing one screw and then switching to the other so that the mounting rings are evenly tight.

After you are done installing this, you should use a knife for trimming the plumber’s putty that may have squeezed out from the flange.

  1. Mount the Garbage Disposal

This step is where the actual installation of the garbage disposal unit takes place. You must be very careful as it can get a little heavy and you can end up straining yourself if you are not careful. Now, the garbage disposal should be placed on to the mounting ring so that the outlet is face to face with the connection of the drain pipe. Then, make it tight enough so that the garbage disposal stays in place.

  1. Connect to the P-Trap

Now, measure the discharge pipe and cut it to the perfect size through a hacksaw. Then, attach it to the garbage disposal’s outlet. Now, attach the discharge tube of the dishwasher as well.

  1. Check the Disposal

Now that you are done installing it, it’s time to check whether the disposal is connected properly. Turn the power on, run water in the sink, and turn the garbage disposal on to see whether it is working or not. Also, check under the sink to make sure there are no leaks. Once you have determined this, run some food through the garbage disposal in order to check if it is getting properly disposed of.

Optional: Dishwasher Connection

In many garbage disposal units, there is an option to connect the unit to the dishwasher as well. As a result, the dishwasher can drain its water via the garbage disposal unit. If you have such a unit, you can install the dishwasher through the steps mentioned below:

  1. You will find the dishwasher inlet near the disposal chamber’s top. With a screwdriver and a hammer, you can loosen the plug.
  2. Now, you can take out the plug from the disposal unit.

How to Change a Garbage Disposal Unit

It may be possible that you are required to change or replace an older garbage disposal unit instead of installing one for the first time. Since most units last for at least a decade, when it’s time to change them, many new models, styles and designs have been introduced to the market. In fact, the way they are installed, operated and run have also changed over time. Most people would not even remember how they had installed their garbage disposal unit long ago and how to take it out now. The steps below can help and guide you in the process:

  1. You must turn off the electrical power from the circuit breaker box and cover the box so that no one will turn the power back on by mistake. Now, remove the cover from the base of the old garbage disposal unit, loosen the screws and detach the wire connectors.
  2. The dishwasher connection (if any) should be disconnected from the drain crosspiece by loosening the bolts through which is connected to the disposal of the drain flange.
  3. Most garbage disposals are attached with a three-tab mounting ring. You must rotate the ring in the anti-clockwise direction while holding onto the garbage disposal from below until the garbage disposal is detached. Now, you can detach the drain and retaining ring and clean the old plumber’s putty.
  4. Now that your old garbage disposal unit has been removed, you can simply install a new one by following the steps mentioned above.

Benefits of Installing a Garbage Disposal Unit

Having a garbage disposal unit at your place brings a lot of convenience to your home and a lot of benefits which you may not have thought about. Once you have a garbage disposal system up and running at your place, you will surely wonder how and why you ever lived without one! Following are just a few of the benefits you stand to gain if you install a garbage disposal system:

  1. It helps reduce the total amount of waste that ends up in the landfill. Food waste generally makes up the second largest category of MSW, which is the municipal solid waste that is sent to landfills each year. This means about 30 million tons of food waste are sent by US households to landfills, which is wastage of a valuable resource. By using a garbage disposal system, you can alleviate some of this burden.
  2. When scraps of food are processed in the correct manner, they are able to enhance soil quality as a natural fertilizer. It can also be used to generate renewable energy as well as to feed animals.
  3. The new garbage disposal systems nowadays have some great new features which include a quiet operation and increase in the grinder capacity. They also usually offer ease of installation. This makes it inexpensive to increase your overall quality of life and your home’s overall appeal.
  4. Once you have installed a garbage disposal system at your place, you will not have any food scraps decaying around your garbage cans. This way, not only does it help improve the smell in your house, but it also helps cut down the number of bacteria, which can make the living conditions better and improve the sanitary conditions.
  5. When the food is not disposed of properly, it can lead to various adverse health effects as it ends up in landfills. The same food generates bad smell and heat-trapping gases such as carbon dioxide and methane. Moreover, when the food waste ends up in landfills, it is incinerated, which means it releases harmful pollutants in the air that lead to various issues like cardiovascular diseases and respiratory problems.
  6. Using a proper garbage disposal system means that it is simpler to put food waste in the proper place. The disposal of food in the traditional way is not only a messy and a smelly job, but it also attracts animals and insects when it is not disposed of properly. Having bagged garbage also leads to unsanitary conditions around the house. A garbage disposal unit will keep you away from all such issues.
  7. The system of garbage disposal units has become very affordable nowadays as well as easy to install, irrespective of the age of the home. The models available today are more advanced, quieter and work more smoothly as compared to their older counterparts. They have a wide range of horsepower available that ranges from 1/3 to a full horsepower capacity as well. Installation is such a breeze in most of these garbage disposal units that most of the times, the user can do it themselves without requiring any outside help. This makes it all the more easy to use a garbage disposal unit.


A garbage disposal unit has become very common in most homes due to the various benefits it provides to homeowners. It helps provide better sanitation and improve the quality of life. The best part about having this unit in your kitchen is that installing it is very simple and easy. You can even do the installation yourself. Most people do not even require a plumber to do the job for them.

It is advisable to start the process of installation early in the day so that if there are any problems during the installation process, you can visit the hardware or plumbing store for extra materials, tools or supplies that you may need. It is better not to begin the installation process when the hardware stores are closed or if you do not have the right supplies. Always make sure you have everything you need beforehand.

Even if you have done the same process before, you must still read the instructions from the user manual. Sometimes, the process could be different for different models. As long as you follow all the steps and instructions mentioned above and in the manual, you will have your garbage disposal unit up and running in your kitchen in no time!

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