Continuing with our commercial kitchen design guidelines sinks tend to be one of the more challenging aspects required in a commercial kitchen due to the quantity and variety that are needed. The installation information provided below for the commercial kitchen design guidelines sinks may vary in requirements for each jurisdiction so it is very important to follow local requirements. A qualified restaurant consultant will become very valuable in this aspect of your commercial or restaurant kitchen design by doing the research needed to ensure proper connections, potentially saving you valuable time by not delaying the permitting process.
When installing sinks, there are two types of drain connections that are made. They are either direct drained, or indirectly drained. Direct drained sinks are similar to what you find in a residential home; the sink being connected to the sewer via a P or S trap type of pipe system. Indirectly drained sinks mean that the drain pipe that is connected to the sink, empties into a floor sink, typically having an air-gap between the pipe and the sink, being two times the diameter of the pipe. This is done to ensure that should the sewer system back-up for any reason, the discharging sewage will not come into contact with any food contact surfaces.
Most commercial kitchen design projects will require at minimum 4 types of sinks.
One mop sink, for obvious reasons.
- May be either floor mounted as in the image above, or similar in design to a utility room sink you might find in a residential building.
- These sinks are typically direct drained.
Typically one hand sink for every twenty feet of radial work space is the rule of thumb for most health departments.
- Depending on the proximity of the hand sink in relation to food contact surfaces, you may need to invest in a hand sink that has integrated splash guards as depicted in the image above.
- Hand sinks are always direct drained.
One preparation sink which may be one or two compartments, also having one or two drainboards. These sinks may also be integrated into a table as in the image above.
- There is no set code for number of sinks or drainboards, but your commercial kitchen design consultant should advise you as to which is best for your particular situation.
- Preparation sinks area always indirectly drained.
One three compartment sink for scullery or pot washing have two (preferably) or one drainboard, if permissible by the local authority, assuming you also provide a drying area for washed equipment.
- There are sometimes exceptions to this code as it pertains to limited preparation kitchens such as coffee shops and juice bars. Some local authorities will also allow a dishwasher in lieu of a three-compartment sink in these same limited preparation kitchens.
- These sinks are always indirectly drained.
The footnote to the above commercial kitchen design guidelines sinks (some or all) may be required to be connected to individual, or common sewer system grease traps. Since most sewer systems were designed and built almost a 100 years ago, by reducing the volume of organic matter entering into it, the towns reduce their repair and maintenance costs.
To further reduce the amount of organic matter entering into the system, some municipalities also require garbage disposals to be installed on preparation, scullery and dish machine sink bowls. This helps to pulverize the food waste, making it more easily retained by the grease traps.
All sinks are required to be supplied by adequate hot water service from an appropriately sized hot water heater. This sizing determination is typically done by the Mechanical, Electrical and Plumbing Engineer.
Your contracted restaurant consultant should advise you as to which of the above requirements pertain to your concept as you progress in the pre-design programming phase of your project.