Where things go in a commercial kitchen, and why

Most of what determines whether a kitchen works is decided on a drawing, in an afternoon, by someone who will never cook in it. Very little of it is in the food code. The code tells you what you may not do; the rest is yours, and the rest is where the money is.

This is what the rules actually say, followed by the adjacencies that are not rules but will cost you anyway. Everything cited as “the code” here is the State of Ohio Uniform Food Safety Code, Chapter 3717-1 of the Administrative Code, which is public, free, and worth a bookmark — every claim below links to the specific rule so you can check it.¹⁴

The organizing idea is flow, not the work triangle

The residential work triangle does not transfer. A commercial kitchen is a production line, and the model is the flow of food — receiving, storage, prep, cook, hold, serve, then warewashing and waste — moving in one direction, with clean and soiled paths crossing as rarely as possible.

The test to apply to any drawing: trace the path of a dirty plate from the dining room to the dish machine, and see what clean food it passes over. If it crosses the prep table, the layout is wrong, and no amount of procedure will fix it permanently. That crossing is also one of the things a plan reviewer is looking for.

What the code actually dictates

Less than people expect, and it is worth knowing exactly where the line is.

Equipment may not be located here

Equipment, food storage cabinets, and cabinets storing cleaned equipment, utensils, linens, or single-service articles are not to be located:¹

• In toilet rooms, garbage rooms, or mechanical rooms
• Under sewer lines that are not shielded to intercept drips
• Under leaking water lines, including leaking fire sprinkler heads, or under lines on which water has condensed
• Under open stairwells
• Under other sources of contamination

The condensation clause catches people in older Cleveland buildings, where an uninsulated cold line running over a prep area is common and is a violation the day someone notices it.

Spacing and sealing

Fixed equipment — anything not easily movable — must be installed so it is:¹

• Spaced to allow cleaning along the sides, behind, and above it; or
• Spaced from adjoining equipment, walls, and ceilings by no more than 1/32 inch; or
• Sealed to adjoining equipment or walls, where exposed to spillage or seepage

There is no legal middle ground, and the middle ground is exactly where most kitchens land: a three-inch gap behind a range, too tight to clean and too wide to be sealed. Either commit to a cleanable gap or close it properly.

Height off the floor and counter

Casters count as movable, which is why so much modern equipment ships on them. A unit on casters that you can actually roll out solves the cleaning-access problem without legs — but only if there is room to roll it out, and only if the utility connections are flexible enough to allow it. Check both on the drawing.

Surfaces, junctures, and the carpet rule

Floors, floor coverings, walls, wall coverings, and ceilings must be smooth and easily cleanable.⁸ Beyond that:

• Floor and wall junctures must be coved and closed to no more than 1/32 inch where floors are cleaned without water flushing. Where water flush cleaning is used, floors need drains and grading to drain, and the junctures must be coved and sealed.⁸
• No carpet in food preparation areas, walk-in refrigerators, warewashing areas, toilet rooms containing handwashing sinks or toilets, refuse storage rooms, or anywhere the floor is subject to moisture, flushing, or spray cleaning.⁸
• Exposed horizontal utility lines and pipes may not be installed on the floor, and exposed lines generally may not obstruct cleaning of floors, walls, or ceilings.⁸
• Studs, joists, and rafters may not be exposed in areas subject to moisture.⁸ Concrete block or brick used for indoor walls must be finished and sealed except in dry storage.⁸
• Light bulbs must be shielded, coated, or otherwise shatter-resistant wherever there is exposed food, clean equipment, utensils, linens, or unwrapped single-service articles. Heat lamps need a shield extending beyond the bulb so only the face is exposed.⁸
• Attachments to walls and ceilings — light fixtures, vent covers, wall fans, decorative items — must be easily cleanable, except decor in the consumer area kept clean for ambiance.⁸
• Toilet rooms must be completely enclosed with a tight-fitting, self-closing door, unless they sit outside the operation and do not open into food prep.⁸
• Insect control devices may not be located over a food preparation area, and must retain the insect rather than fling fragments onto food.⁸
• Outer openings must be sealed against insects and rodents — gaps filled, windows tight-fitting, doors solid, self-closing and tight-fitting. Openings kept open for ventilation need 16-mesh-to-the-inch screens, properly designed air curtains, or another effective means.⁸
• HVAC must be designed and installed to the Ohio Building Code, and make-up air intake and exhaust vents must not contaminate food, food-contact surfaces, equipment, or utensils.⁸

The coving requirement is the one that most often turns a cheap second-generation deal into a real floor job. It is not a finish preference; it is a dimension, and it is checkable with a straightedge.

Lighting, which nobody puts on the plan

Light intensity is specified by area, measured 30 inches above the floor:⁹

Two of these get missed almost every time. Inside the reach-ins — an interior light is a specification, not a luxury. And 50 foot-candles at the prep bench, which is a genuinely bright number and the reason so many retrofits end up adding fixtures after the electrician has gone.

Mechanical ventilation of sufficient capacity is required wherever it is needed to keep rooms free of excessive heat, steam, condensation, vapors, odors, smoke, and fumes.⁹

How many people, and how many restrooms

Occupant load and plumbing fixture counts are building and plumbing code rather than food code, and they decide how much of your floor plan the dining room can actually use — see occupancy limits and how many restrooms you need. The short version: dining with tables and chairs is 15 square feet per person, a commercial kitchen is 200, and a bar needs roughly twice the water closets of a restaurant with the same occupant load.

Rooms and areas that need to exist

Easy to leave off a drawing and awkward to add later:

• Dressing rooms or areas, designated, if employees routinely change clothes on site — plus lockers or other suitable facilities for their clothing and possessions, located where they cannot contaminate food, equipment, utensils, linens, or single-service articles.⁹¹⁰
• A designated area for employees to eat, drink, and use tobacco, located so food and equipment are protected.¹⁰
• A segregated area for distressed merchandise — damaged, spoiled, or recalled product held for credit or return — separated from food, equipment, utensils, linens, and single-service articles.¹⁰
• Toilet rooms conveniently located and accessible to employees during all hours of operation.¹⁰

Sinks: four fixtures, not one

• Three-compartment warewashing sink, with compartments large enough to immerse your largest item, plus drainboards, racks, or tables on both ends big enough for everything that accumulates during service.²
• Handwashing sinks, located for convenient use by employees in food preparation, food dispensing, and warewashing areas, and in or immediately adjacent to toilet rooms.⁴ A handsink may only be used for handwashing;⁴ a warewashing sink may not be used for handwashing.⁵
• At least one service sink or curbed cleaning facility with a floor drain, conveniently located, for mops and mop water.⁴
• A prep sink in practice, if you wash produce or thaw food — otherwise the warewashing sink has to be cleaned and sanitized before and after every such use.⁵

Each handsink or adjacent pair also needs soap, a drying method (disposable towels, continuous towel system, warm-air dryer, or air-knife), a waste receptacle if towels are used, and handwashing signage clearly visible to food employees.⁹

And the mirror-image rule people trip on: a food prep sink, a utensil sink, or a mop sink may not be fitted with soap and towels.⁹ Putting a soap dispenser over the prep sink does not create a handsink. It creates a violation, because it invites the sink to be used as one.

The practical handsink test is not the drawing, it is the shift: can a cook reach one without leaving their station, opening a door, or squeezing past someone? If the answer is no, it will not get used, and no amount of training changes that. Adding one during the build is cheap. Adding one after is a floor, a drain, and a shutdown.

Ventilation

Hood systems must be sufficient in number and capacity to prevent grease or condensation collecting on walls and ceilings,² and hoods, fans, guards, and ducting must be designed so grease or condensation cannot drain or drip onto food, equipment, utensils, linens, or single-service articles.³

That is the food code’s whole contribution. The dimensions come from the mechanical code.

What the plan set has to show

Ohio specifies the contents of a facility layout and equipment specification submission, and the list is short enough to check yourself before you pay someone to redraw it. Plans must be legible, drawn reasonably to scale, and include:¹¹

1. The type of operation proposed and the foods to be prepared and served
2. Total square footage used for the operation
3. A site plan — where the business sits in a building such as a mall or stadium; where the building sits on the site including alleys, streets, dumpsters, potable water source and sewage treatment system; and interior and exterior seating
4. Entrances and exits
5. Location, number and types of all plumbing fixtures, including water supply facilities
6. A plan of lighting
7. A floor plan showing all fixtures and equipment
8. Building materials and surface finishes
9. An equipment list with manufacturers and model numbers

Items 6 and 9 are the usual omissions. A drawing without a lighting plan and a model-number equipment schedule is an incomplete submission, and an incomplete submission is what turns a 30-day review into a 60-day one.

Two things worth knowing about what the licensor can do with it. They may place restrictions or conditions on your license limiting the types of food you may prepare, based on the equipment and facilities you showed them — and those limitations are posted on the back of the license.¹¹ For mobile operations, the menu, the layout, the location and type of major equipment, and any restrictions all go on the back of the license.¹¹ Your plan set is not a formality; it is the document that defines what you are allowed to cook.

Equipment has to be certified

Food equipment acceptable for use must be approved by a recognized food equipment testing agency for sanitation.³ In practice that means the NSF, UL, ETL and similar marks you see on a spec sheet. The licensor, ODA, or ODH may approve equipment that has not been certified if it demonstrates compliance with the chapter — which is a real path, not a formality, and it is the one you are relying on if you buy something unmarked, imported, or fabricated to order.³ Ask before you buy, not after it is bolted down.

The hood sets the cook line before you pick the equipment

Ohio adopts Chapter 5 of the 2021 International Mechanical Code for exhaust systems.⁶ Under section 507.1.6, for both Type I and Type II hoods:⁷

• Canopy hoods — the inside lower edge must overhang at least 6 inches beyond the edge of the appliance’s top horizontal surface on all open sides, and the vertical distance from the front lower lip to that surface must not exceed 4 feet.
• Noncanopy hoods — no more than 3 feet above the cooking surface, with a setback of no more than 1 foot.

Read that as a design constraint rather than a compliance detail, because it has a consequence people discover late: your hood length fixes your cook line length. Every appliance producing grease-laden vapor has to sit under the hood with 6 inches to spare on every open side. Deciding a year in that the menu needs one more fryer usually means the hood no longer covers the line — and a hood extension is engineering, permits, fire suppression rework, and often make-up air.

The cheap version of this decision is to buy hood length you do not yet need while the hood is being fabricated. The expensive version is everything else.

The refrigeration-next-to-heat question

This is the most common instinct people have about layout and it is correct, though usually for the wrong reason. There is no rule in the Ohio food code that says a reach-in may not sit beside a fryer. What the code says is that equipment for cooling, heating, or holding must be sufficient in number and capacity to keep food at the required temperatures.²

That is the whole trap. The placement is not the violation. The placement is what creates the violation, on the first hot Saturday when the box cannot pull 41°F and the inspector is standing there with a probe.

Every piece of commercial refrigeration is built and rated to operate within a maximum ambient temperature, published in the manufacturer’s specification sheet for that specific model. A reach-in tucked against a fryer battery, or a top-mount unit breathing the hottest air in the room, can sit outside that envelope during service. What follows is predictable:

• The compressor runs closer to continuously, so it wears out sooner
• Energy use rises for the same amount of cold
• Recovery after a door opening slows, which is when product actually warms
• Warranty conversations get difficult, because operating outside the manufacturer’s stated ambient conditions is a standard exclusion

Condenser position matters as much as distance. Bottom-mount units pull floor-level air — cooler, but also greasy, dusty, and in the path of mop water, which is one reason those coils clog. Top-mount units pull air from the hottest layer in the room. Near a hot line, top-mount is the worse choice; in a flour-heavy bakery or a room that gets swept constantly, bottom-mount is.

What to do instead, in rough order of value:

1. Keep refrigeration off the hot line entirely where the plan allows it — the pass, the prep side, or the far end.
2. Read the manufacturer’s clearance specification for the specific model and put those dimensions on the drawing. They vary a lot and they are not negotiable in a warranty claim.
3. Give the condenser air that is not the line’s exhaust. Never point a condenser discharge at another unit’s intake.
4. Do not build a reach-in into a tight alcove without checking that the clearance spec allows it.
5. If refrigeration next to heat is genuinely unavoidable, specify equipment rated for high ambient rather than hoping.

Ice machines deserve the same thought and rarely get it. They are heat-rejecting equipment with an ambient rating, they lose production capacity as the room warms, and they need a drain. A machine that makes its rated poundage in a test lab and two-thirds of it in your actual room is not defective — it is badly placed.

Adjacencies worth getting right on paper

• Receiving to storage should be short and should not cross production. If deliveries come through the kitchen, you have a traffic problem every morning and a contamination argument at every inspection.
• The walk-in belongs near receiving, not near the line. It is the heaviest traffic item in the building and the cook line is the worst place to put a door that opens constantly.
• Dish return should reach the dish pit without passing prep. This is the single most valuable line to draw first.
• The mop sink belongs away from food prep and near where the mopping starts. It also needs the floor drain, so its location is a plumbing decision made early or an expensive one made late.
• Dry storage wants to be off the hot line. Ambient heat shortens shelf life and encourages pests, and shelving that is easy to reach from prep is shelving that stays organized.
• Leave a landing zone at every door and every oven. Door swings, oven doors, dish machine hood lifts, and sheet pan racks all need floor they do not share. This is the detail most often missing on otherwise competent drawings.

Walk-ins, and the decision made at slab pour

A walk-in is the one piece of equipment that is really construction, and the part that gets decided too late is the floor.

What the code says, which is the easy half:

• Floor-mounted equipment not easily movable must be sealed to the floor or on 6-inch legs.¹ A walk-in is sealed.
• No carpet or similar covering in a walk-in refrigerator — it is on the list of areas where it is prohibited outright.⁸
• At least 10 foot-candles of light, measured 30 inches above the floor.⁹
• A floor drain originating in a refrigerated space constructed as an integral part of the building is excepted from the indirect-connection requirement that applies to other food and utensil drains.¹³ Which is a clue that the code contemplates the box being built into the slab rather than set on top of it.

What the code does not say, and what actually costs money:

A freezer holding below freezing over a slab on grade will, over time, pull the ground beneath it below freezing too. Moisture in that soil expands, and the slab above it moves — the trade calls it frost heave, and the repair is concrete work under a running box. Coolers are usually fine sitting on an existing floor. Freezers frequently are not, and that is a structural question rather than an equipment one.

The common answers are an insulated freezer floor panel, a recessed slab so the finished floor sits flush, or some form of under-slab heat — and which one is right depends on your soil, your slab and the box temperature. That is an engineer’s call, not a web page’s.

What this page can usefully tell you is when to ask. All of it is decided at slab pour. Retrofitting a recess means cutting and repouring concrete inside a finished building, so put these to your designer and refrigeration contractor while the floor is still on paper:

1. Is the freezer floor insulated, or is the slab? One of them has to be.
2. Are we recessing the slab so the floor is flush, or accepting a threshold and a ramp? A ramp is a daily reality for anyone moving a loaded cart, and nobody enjoys it.
3. What is under the insulation — and does this soil and this slab need under-slab heat, given the box temperature we are running?
4. Where does the condenser go and where does its heat land? Remote versus self-contained changes the roof, the electrical and the noise.
5. Is there a floor drain in the box, and how is it configured?
6. What door swing and clearance does a loaded speed rack actually need, as opposed to a person?

If your build has a freezer in it, this is the conversation to have before the concrete is ordered. Everything else in this guide can be fixed later at some price. This one gets fixed by demolition.

Grandfathering ends when the business sells

This is the single most expensive thing on this page, and it is one short rule.

Existing facilities and equipment must be replaced with equipment and facilities meeting the current requirements of the chapter when any of the following happens:¹²

• They stop being in good repair or maintainable in a sanitary condition
• Their food-contact surfaces stop complying
• Their cooling, heating, or holding capacities stop complying
• They no longer meet the criteria they were originally approved under
• They constitute a public health hazard, or
• The operation changes ownership

Read that last one twice. Buying a running restaurant does not inherit its exemptions. The wooden shelving, the uncoved floor juncture, the reach-in that was fine in 1998, the three-bay that is an inch too small for a full sheet pan — all of it was legal for the previous owner because it predated a rule, and none of it necessarily stays legal for you.

This is why a second-generation space can look like a bargain and price like a build. Before you sign anything, walk the kitchen with someone who reads this chapter for a living and get the list of what transfers and what does not. That conversation costs a few hundred dollars. Not having it has cost people their entire contingency.

Before the drawing is final

1. Trace the dirty-dish path. Does it cross clean food? Fix that first.
2. Count the handsinks by station, not by square footage, and stand in each station mentally to check reach.
3. Confirm the hood covers every grease-producing appliance with 6 inches on all open sides — and ask what a future appliance would cost you.
4. Put manufacturer clearance dimensions for refrigeration on the plan, not just the equipment footprint.
5. Check that anything on casters can actually roll out, utilities included.
6. Verify nothing sits under a sprinkler head, a sewer line, or a cold line that sweats.
7. Look for the three-inch gap — the one that is neither cleanable nor sealed — and resolve it now.

Plan review will catch the code items. It will not catch a kitchen that is legal and miserable to work in. That part is on the drawing, and the drawing is the cheapest thing in the whole project to change.

If you are hiring for this stage, the architects and designers and general contractors categories list firms with foodservice experience, which is the qualification that matters here — a competent commercial architect who has never done a kitchen will produce a building that passes and a line that does not work.