Restaurants and commercial kitchens of all sizes are required to install a grease trap in their kitchens although coding issues on this piece of equipment differs from region to region. You can read the Georgia State codes on the installation of traps, interceptors and separators here.

It’s important to get the right size because if you purchase one that’s too small, you can very well end up with overflow messes and that’s never a good thing. But if you install a grease trap that’s too large, you’re just wasting your money!

So, you want to make sure to take a little time and possibly consult a professional plumber to help you determine the best size grease trap for your kitchen.

A grease trap (aka Grease Interceptor) is a piece of plumbing equipment that is hooked up to a kitchen’s drain pipe. It’s purpose is to collected Fats, Oils and Grease (commonly referred to as FOG) and basically prevent them from going into the sewer system.

Basically, once the FOG is collected, it begins to cool down which then separates it from the rest of the liquid and other solid debris. You’ll notice that when you open a grease trap, the first thing you will see is a thick layer of FOG sitting on top of the remaining liquid in the unit.

How To Properly Size A Grease Trap

Basically, the number of sinks, glass washers and dishwashers that are in the kitchen will dictate the size of the grease trap that you need.

The sizing of grease traps should be according to the rate of incoming flow. This is expressed as the number of gallons per minute or GPM. Additionally, the trap’s capacity must be taken into consideration. The capacity is rated in pounds. The rated capacity is twice the flow rate. Here’s an example to help you. A 10 GPM grease trap has a rated capacity of about 20 pounds. –

Here are some tips to help you get the right size grease trap for your commercial kitchen.

1. There are multiple factors that go into calculating what size grease trap is best for your kitchen. These include…

  • The number of sinks you have.
  • The size of each sink.
  • The number of dishwashers you have
  • The number of floor drains and sink drains
  • The flow rate and drainage period of your fixtures

The information of all of these factors are all calculated (as you will see in the sizing calculator mentioned below) to help you determine what the proper size of grease trap you should have.

Handy Grease Trap Sizing Calculator

If you’re still not quite sure what size grease trap you need – use this great little calculator by

If you have any questions about grease traps or are having some problems with it, call Atlantis Plumbing today at 770-443-8229. We are available 24 hours a day, 7 days a week.