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What Size Garbage Disposal Do I Need?

What Size Garbage Disposal Do I Need?

Garbage disposals are a good way to process most of your kitchen organic waste and reduce how much you end up sending to the trash can. Choosing something too small for your kitchen or home needs will lead to slow processing and jams. Picking something too big leaves you with a power guzzler that might not fit under your sink.

Choosing the right size disposal gives you sufficient performance without forcing you to break the bank buying something that is too big for your needs.

The top factors that will determine the size and type of garbage disposal you go for are:

  • How much physical space do you have under your kitchen sink
  • How big is your family
  • How often do you cook
  • What kind of food do you cook

Even though the physical size of the garbage disposal might vary, most of the sizing emphasis is on the motor’s size. 

A bigger motor means a stronger garbage disposal that can process more leftovers faster without bogging down. Even though more powerful motors might be in a bigger housing, a 1 hp garbage disposal is still bigger than a ¾ hp unit even if they are of same physical dimensions.

Do You Have Enough Space for the Garbage Disposal Under Your Sink?

The first thing to consider before choosing a brand and size is whether the space you have in your kitchen is enough for the garbage disposal.

Size up the space and take measurements. The goal is to ensure you have enough space to fit in the garbage disposal, accompanying plumbing and wiring while still leaving some clearance space around the unit.

A bigger garbage disposal will be useless if you can’t squeeze it under your kitchen sink. Luckily, most kitchens have an empty cabinet under the sink so space shouldn’t be a problem unless you are already using this space for something else, say a water filter.

Number of People in the House

The number of people in the house is directly proportional to how much waste you generate in the kitchen. The more the people the more food you have to cook. This means:

  • You will have more peelings from processing foods like onions, potatoes and other necessary ingredients when cooking
  • The potential of having to grind left overs is slightly more
  • You will have more waste from food that isn’t necessarily left overs. This includes bones, seeds and other organic but inedible parts of a meal

The more the people the bigger the garbage disposal you need.

How Often Do You Cook?

The cooking frequency will again determine how much waste and food remains the garbage disposal has to handle per day.

For instance, two roommates who eat out 90 percent of the time will make do with a smaller garbage disposal compared to one person who loves cooking and prepares all his meals in the house.

If you cook often, you will have more waste and need a bigger, stronger garbage disposal that can process the waste fast and run for longer hours.

If you don’t cook often, a smaller disposal will be slower but it will still get the job done. Since you don’t run it as often, it will still serve you well for many years to come.

What Type of Food Do You Cook?

The final consideration will be the type of food you often cook. Some foods have tougher leftovers and scraps than others. For instance, ribs are tougher than vegetable scraps.

It follows that a vegan can make do with a weaker garbage disposal than a grill master who is always throwing some ribs, chicken or other types of bony waste into their garbage disposal.

Choosing the Correct Size Garbage Disposal For Your Use Case

Now that you know what determines the garbage disposal size that is perfect for your needs, it is time to look at what sizes matter other than physical dimensions that you can take with a tape measure under the kitchen sink.

Fitting and Fixture Size

This is all about measuring whether the garbage disposal will fit your kitchen sink. 

  • Will it fit the space under the sink without any modifications?
  • Will all the connections fit into the existing sink and waste pipes or do I need any modifications

The physical size and fitment will through a couple of curve balls but they are by far the easiest to work around. You can always create some space or bolt on adapter fixtures.

Grind Chamber Capacity

The grind chamber is where the food sits before the impellers on the garbage disposal grind it up. A bigger grind chamber could mean your disposal can process more waste at a go. The average is 26 ounces with bigger units going up to 40 ounces.

Though useful, it shouldn’t bother you much unless you intent to pile up food into your disposal before turning the button. I would pick a powerful or faster disposal with a small grind chamber any day over a unit with a weaker motor but a bigger grind chamber.

Check this too: How to Properly Use a Garbage Disposal

Grinding Motor Horsepower (HP)

Motor size is by far the most popular way to size a garbage disposal. Its impact on a unit’s performance is so profound to the extent that most manufacturers and plumbers prefer using this figure to size a unit. 

  • 1/3 HP: Cheapest lowest power. Ideal for a very small house with less demands. Might have a hard time processing tough waste
  • ½ HP: Most common size ideal for small families that cook often
  • ¾ HP:  Perfect for most households. Sufficient grinding power for the family and some occasional guests
  • 5/8 HP: Strong enough to grind tough ingredients and process more waste. A bit bigger and needs more physical space
  • 1 HP: Perfect for large families, people who love to entertain, or small restaurants. Can grind virtually anything you could logically through down it
  • 2 HP: Perfect for large commercial properties or large extended families where budget isn’t a problem

Here is a brief breakdown of what garbage disposal you should choose depending on your family size, how often you cook and what you cook.

Motor Size Family SizeCooking FrequencyFoods Cooked
2 HPOver 10 people/restaurantMore than once a dayTough bone meat like ribs, fruit pits, soft foods, vegetables, fish, leftovers, cereals, leftovers, raw meat
1 HPOver 4 peopleDailyRib bones, fruit pits, chicken bones, raw meat, fish bones, cooked meat, vegetable or fruit scraps
¾ HP2-4 PeopleCouple of times a weekChicken bones, soft foods, fruits, raw meat, cooked meat, fish bones, leftovers
½ HP1-2 PeopleOnce a weekSoft foods, fruits, fish bones, cooked meat, vegetable scraps, leftovers
1/3 HP1-2 PeopleRarelySoft foods, fruits, vegetable scraps, leftovers