MEP for Restaurants

The Kitchen Is the Whole Game

Four things across the cook line and prep area set the tone for the entire MEP design:

1. The exhaust hood. Cooking equipment that produces grease-laden vapor needs a Type I hood and grease-rated ductwork; a Type II hood handles heat and moisture (dishwashers, ovens without grease). The hood type, size, and duct routing are governed by the mechanical code (IMC) and NFPA 96 (the standard for commercial kitchen ventilation), and they cascade into the rest of the mechanical design. One practical detail that matters more than it sounds: grease-duct cleanouts have to be reachable, because they have to be cleaned — regularly, for the life of the building.

2. Make-up air. Every cubic foot the hood exhausts — its exhaust CFM — has to be replaced, usually through a dedicated make-up air unit (a DOAS or rooftop RTU) sized to match the hood. If it isn't — if make-up air isn't balanced to the hoods — the building goes negative: doors whistle and are hard to open, the HVAC fights itself, and in winter the dining room freezes while the kitchen pulls cold air through every crack. Make-up air isn't optional; it's half the ventilation design, and it's what an air balance confirms before occupancy.

3. Grease. Kitchen wastewater carries grease that can't go straight to the sewer, so it runs through a grease interceptor sized and placed per the local sewer authority's rules and the plumbing code (IPC) — part of the same plumbing design that covers floor drains, floor sinks, and backflow prevention on the domestic feed. Get the interceptor's sizing or location wrong and it's a health-department and plan-review problem — and a very unpleasant one to fix after the floor is poured.

4. Gas. Cooking equipment gas loads have to be reconciled against the actual equipment package, line by line, and the gas piping and regulator sized for it. When the equipment schedule changes late (it usually does), the gas design has to keep up.

Why the Equipment Schedule Runs the Show

Here's the thing that surprises people: in a restaurant, the *kitchen equipment schedule* drives much of the MEP. Every piece of cooking equipment — the range, the walk-in cooler, the dish machine — has a power requirement, a gas load, an exhaust demand, or a plumbing connection, often several, and the electrical side gets sized off a panel and load calc that applies equipment diversity rather than assuming every appliance runs flat-out at once. The MEP can't be finalized until that equipment package is reasonably locked, ideally by the end of design development, because the numbers come straight from it. (See how to read an MEP equipment schedule for what that document actually shows.)

This is why late equipment changes are so costly on restaurants specifically. Swap a range for a larger one and you may have moved the gas load, the hood size, the make-up air, and the electrical all at once. The single best thing you can do to protect your budget and your timeline is to firm up the kitchen equipment early and get it to your MEP engineer.

The Dining Room Still Matters

Beyond the kitchen, a restaurant is an assembly space, and that carries its own MEP:

• Comfort and odor control — the dining room has to stay comfortable while the line runs hot, sized to ASHRAE ventilation guidance and sometimes trimmed with demand-control ventilation, and kitchen and trash odors have to be kept out of the guest area by design, not by luck.
• Restrooms — fixture counts are driven by occupancy, and assembly occupancies pack a lot of people into a small footprint.
• Lighting and power — dining ambiance lighting and dimming control, egress and emergency lighting, patio and signage circuits, and dedicated equipment circuits sized to the electrical code (NEC) as part of the building's electrical design, plus the hood fire-suppression interlocks — the emergency shutoff that cuts gas and power — covered in more detail below.

How Fire Protection & Hood Suppression Coordinate

A commercial kitchen has real fire-protection requirements — but not all of them are MEP's to design, and the boundary matters:

• The exhaust hood and grease-rated ductwork are mechanical MEP work, designed to the mechanical code and NFPA 96 (commercial kitchen ventilation).
• The wet-chemical hood suppression system (the "Ansul-type" system over the cooking line, to NFPA 96 / NFPA 17A) is a listed system designed and installed by the fire-suppression contractor — by others. MEP's job is to coordinate the interlocks: when that system trips, it must shut off the gas to the appliances and cut power to the hood/equipment. Designing those electrical and gas shutoff interfaces cleanly is on MEP.
• Building fire sprinklers and fire alarm are designed by the fire-protection engineer — by others. MEP coordinates ceiling/shaft space and the power/monitoring interface.

The reason this coordination is worth naming: the fire marshal reviews the kitchen closely, and a suppression system whose gas/power shutoff interlock wasn't coordinated is exactly the kind of thing that fails at inspection. For the fuller by-others picture, see MEP scope: who's responsible for what.

MEP by Restaurant Type: Fast-Casual to Ghost Kitchen

The kitchen drives the MEP — but which kitchen changes the whole load picture:

• Fast-casual / QSR. Smaller cook line, but often heavy fryer/griddle loads concentrated tight — hood and make-up air still dominate; electrical is dense per square foot.
• Full-service / fine dining. Bigger, more varied cook line (ranges, ovens, broilers), larger Type I hoods, more gas, plus a dining room with real comfort and odor-control demands.
• Bakery / café. Ovens drive heat and sometimes Type II hoods; proofers, refrigeration, and domestic hot water and water-heater sizing matter more than a heavy grease profile.
• Ghost / cloud kitchen. Multiple small kitchens under one roof — the challenge is repetition and separation: metering, exhaust for many hoods, and make-up air balanced across bays.
• Food court / commissary. Shared exhaust and grease infrastructure, tenant metering, and coordination across many operators — the same questions that come up on any mixed-use or tenant fit-out project.

Same four levers every time — hood, make-up air, grease, gas — but the equipment package sets how hard each one pushes.

The Restaurant MEP Mistakes That Show Up at Inspection

Restaurants get reviewed by the building department, health department, and fire marshal — so mistakes surface fast and late:

1. Under-balanced make-up air — the building goes into negative pressure, doors whistle, the dining room can't hold temperature.
2. Grease interceptor undersized or badly located — a health-department and plan-review problem, brutal to fix after the slab is poured.
3. Uncleanable grease-duct cleanouts — code requires access; miss it and every future cleaning is a fight.
4. Gas load not reconciled to the final equipment schedule — a late range swap moves gas, hood, make-up air, and power at once.
5. Suppression interlock not coordinated — the hood system trips but doesn't cleanly cut gas/power (see above).

Almost all of them trace to one root cause: the kitchen equipment package wasn't locked early enough for MEP to design against.