Restaurant Electrical, Gas, Plumbing & Vent Specs: The Operator’s Complete Guide (2026)

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The four utilities decide whether your build finishes on schedule

Equipment shows up on time. Hoods and finishes show up on time. Electrical, gas, plumbing, and vent infrastructure is what blows the schedule, and it does it on roughly 70% of restaurant build-outs. The pattern is always the same: equipment cut sheets weren’t shared with the MEP (mechanical, electrical, plumbing) engineer early, the gas line is undersized for the cookline BTU load, the electrical service can’t carry the production kitchen, the floor sink isn’t where the dishwasher discharge is, and 6 weeks of rework gets bolted onto the schedule at $40,000–$120,000 cost.

This pillar is the procedural reference for getting the four utilities right before construction starts. Treat it as a checklist, not a brand-shopping guide.

Scope: which decisions belong in this pillar

In scope: electrical service sizing, voltage and phase decisions, panel design, gas line sizing and natural-gas vs LP, plumbing rough-in, water supply and sewer specs, and the integration with hood and MUA from the ventilation pillar.

Out of scope (covered elsewhere): the ventilation engineering itself (see Commercial Kitchen Ventilation & Fire Suppression Guide), and the layout decisions that consume these utilities (see Restaurant Kitchen Layout Guide).

The procedural sequence

The order in which infrastructure decisions get made determines whether the build runs smoothly or melts down at month 4. The correct sequence:

  1. Equipment list finalized with cut sheets for every appliance — voltage, amperage, BTU/hr, water supply, drain.
  2. Layout drawn with each piece of equipment placed (see layout pillar).
  3. MEP load calculation — a licensed mechanical / electrical engineer aggregates total electrical load, total gas BTU, total water supply demand, and total drain.
  4. Service capacity verified or upgraded — does the existing electric service carry the load? Does the gas service? If not, what’s the upgrade cost and timeline?
  5. Permitted MEP drawings — engineer-stamped, submitted to the AHJ.
  6. Rough-in trades — electrical, gas, plumbing roughed in at the slab and walls before equipment install.
  7. Equipment install — appliances connected to the rough-in.
  8. Inspection cycle — final electrical, gas, plumbing, and health inspections in the AHJ-mandated order.

Skipping or reordering any step costs money and time. The most-skipped step is #4 (verifying service capacity) — it’s where every “we can value-engineer that later” conversation eventually crashes.

Electrical — the load calculation

NEC 2023 (NFPA 70) Article 422 governs commercial cooking-appliance branch circuits. The key procedural pieces:

Step 1 — Itemize every appliance:

For each appliance: nameplate amperage at nameplate voltage, single-phase or three-phase. Pull from cut sheets, never from “typical” tables.

Step 2 — Sum continuous and non-continuous loads:

Continuous loads (running 3+ hours at a time): hold cabinets, ice machines, walk-in compressors, exhaust fans, lighting. Non-continuous: most cooking equipment, dishwasher, coffee brewers (intermittent).

Step 3 — Apply NEC demand factors:

For commercial kitchens, NEC Article 220 allows demand factors below 100% (typically 65–80%) recognizing not all equipment runs simultaneously. The exact factor depends on equipment count and AHJ interpretation. The engineer applies it; don’t guess.

Step 4 — Determine service entrance size:

Restaurant size Typical service entrance
30–60 cover small restaurant / café 200A single-phase
60–120 cover full-service 400A single-phase or 200A three-phase
120–250 cover full-service 400–600A three-phase
250+ cover / production / multi-concept 800A+ three-phase

Step 5 — Subpanel design:

Cooking line typically gets a dedicated subpanel near the line for short circuit runs and load isolation. Refrigeration sometimes gets its own subpanel for power-quality reasons (motor inrush).

Single-phase vs three-phase service

Single-phase (240V split-phase or 208V): standard for residential and small commercial. Most appliances under 5 kW work fine. Cheaper to bring in.

Three-phase (208V or 480V Y, three-phase): standard for full-service and production kitchens. More efficient for motor loads (refrigeration compressors, mixers, dishwashers), required for many higher-capacity electric ranges and ovens. More expensive service drop (utility may charge $5,000–$50,000 for a new three-phase drop in commercial districts).

Decision rule:

If your equipment list includes any 30A+ three-phase appliance (large electric range, large electric oven, certain dishwashers, large mixer): three-phase is mandatory.

If your equipment list is all single-phase with nothing exceeding 50A circuit: single-phase 200A or 400A may suffice.

If you’re unsure, run the load through the engineer.

Cluster deep-dives:

Gas — the BTU load and line sizing

Gas-fired cooking equipment is the dominant heat source in U.S. commercial kitchens. ANSI Z83.11 / CSA 1.8-2016 (R2021) governs gas food service equipment construction. NFPA 54 (National Fuel Gas Code) governs gas line installation.

Step 1 — Sum total BTU demand:

For each gas appliance: nameplate BTU/hr from cut sheet. Sum the total. A 6-burner range with oven runs ~270,000 BTU/hr at full output; a 3-vat fryer runs ~360,000 BTU/hr; a salamander runs ~36,000 BTU/hr.

Step 2 — Apply load diversity:

Not all gas equipment runs at full output simultaneously. Diversity factor for typical cookline: 70–85%.

Step 3 — Size the gas line:

NFPA 54 tables size gas pipe based on total BTU, line length, and pressure drop allowed. The engineer applies these. Common operator mistake: assuming the existing 1″ gas line is “big enough.” It often isn’t for a converted retail or office space being converted to restaurant.

Step 4 — Verify utility supply pressure:

Most U.S. utilities deliver natural gas at 0.25–7 PSI to commercial buildings. Some commercial appliances require 11″ WC inlet pressure (about 0.4 PSI) — almost always available. A few high-output appliances require higher inlet — verify before spec.

Cluster deep-dives:

Natural gas vs propane (LP)

Natural gas is the U.S. urban / suburban default — piped utility, lower cost ($0.80–$1.50 per therm typical), lower BTU per cubic foot. Most commercial cookline equipment ships configured for natural gas; conversion to LP requires orifice swap and regulator change.

Propane (LP) is the rural / remote / mobile default — tank-supplied, higher cost ($2.00–$3.50 per gallon typical converted to therm equivalent), higher BTU per cubic foot. Required for food trucks, rural restaurants without natural gas service, and some specialty applications.

Decision rule: use natural gas wherever the utility serves the property. Use LP only where natural gas is unavailable or where mobility requires it.

Conversion details: every gas appliance must be ordered or converted to the correct fuel. Mismatched orifice = unsafe operation + voided warranty.

Plumbing — water supply, drain, and code

Hot and cold water supply:

Commercial kitchen hot water demand is dominated by the dishwasher (often 0.5–2 gpm at 180°F final-rinse demand) and the 3-compartment sink (intermittent high-demand fill). A water heater sized for residential demand will not keep up. Common sizing: 75–100 gallon commercial gas water heater (50,000–75,000 BTU input) for full-service restaurants; booster heaters dedicated to dishwasher final rinse are required by NSF/ANSI 3.

Cold water: typical demand 1–3 gpm continuous + ice machine + bar + restrooms. Most existing water service handles it; verify on tenant fit-out projects.

Drain and waste:

Floor drains: required at 3-comp sink, dishwasher, ice machine, kettle / steamer / combi ovens, walk-in cooler floor, and within 25 ft of any cooking equipment per most local AHJs. Floor sinks (open receptors with grates) are required for indirect-drain equipment (ice machines, dishwasher pre-rinse, refrigerated equipment). Indirect drain prevents siphoning of contaminated water back into food equipment.

Grease interceptors:

Required by code for commercial kitchens producing greasy wastewater. Sized by AHJ formula based on fixture count, drain rate, and retention time. Two formats:

Hydromechanical (under-sink) grease trap: 25–100 lb capacity. Fits under 3-comp sink. Adequate for small kitchens.

Gravity grease interceptor (in-ground): 750–3,000+ gallon. Required for full-service and high-volume kitchens. Mandatory in many U.S. cities for any new commercial kitchen.

Pumping schedule: monthly to quarterly, depending on volume. Cost: $200–$700 per pumping.

Vent and HVAC integration

The hood and MUA work was covered in the ventilation pillar. Layout-relevant integration points:

Hood drives MUA capacity, which drives roof or ground-level mechanical placement. The structural team needs MUA size and weight at the schematic-design stage; not at construction documents.

Air balance: the kitchen exhaust + dining-room exhaust + restroom exhaust = supply air (MUA + HVAC). Imbalanced buildings fail HVAC performance and air quality. The mechanical engineer balances the building.

Refrigeration condenser placement: walk-in compressors (often roof-mounted) need clear airflow to dump heat. Don’t put them inside the restaurant. Roof curbs and condensate drains coordinate with structural.

Permitting workflow

For a typical full-service restaurant new build or major renovation:

  1. Pre-application meeting with AHJ Building Department (especially in tier-1 cities). Often required before drawings.
  2. Mechanical, Electrical, Plumbing (MEP) drawings stamped by licensed engineer.
  3. Architectural drawings stamped by licensed architect.
  4. Health Department review of plans (separate from Building Department in most jurisdictions).
  5. Fire Marshal review of hood, suppression, egress.
  6. Permit issued — typical timeline 3–12 weeks depending on city.
  7. Rough inspections during construction at structural, electrical, plumbing, and gas stages.
  8. Final inspections — Building Department (final), Health Department (food prep / equipment), Fire Marshal (suppression), often in this order.
  9. Certificate of Occupancy issued; restaurant may open.

Common delays:

  • MEP drawings without coordinated equipment cut sheets (engineers can’t size loads they don’t have).
  • Health Department requirement changes after Building permit issue.
  • Fire Marshal field changes (additional egress, suppression nozzle relocation).
  • Trade rework when discovered late (gas line undersized — has happened on ~30% of projects we’ve heard about).

Cost reality

Indicative all-in MEP costs for a 100–150 cover full-service restaurant new build (excluding equipment):

Trade Typical cost band
Electrical (rough + finish + service upgrade if needed) $35,000–$120,000
Gas (rough + finish + meter upgrade if needed) $8,000–$35,000
Plumbing (rough + finish + grease interceptor) $25,000–$85,000
HVAC + MUA + hood (mechanical) $40,000–$140,000
MEP design fees (engineer) $8,000–$30,000
Total MEP $116,000–$410,000

The wide range is real — service-upgrade availability and the existing infrastructure of the leased space are the dominant variables. A space previously occupied by a restaurant cuts costs in half. A space converted from retail or office multiplies them.

Frequently asked questions

1. Can my landlord’s existing electrical service handle my restaurant?

Maybe. Most existing retail / office service is rated 200A single-phase, which serves a small café but not a full-service kitchen. Get a load calculation early. If a service upgrade is needed, the utility will quote it; budget timeline of 4–16 weeks for utility work.

2. Why does my gas line need to be upsized when the restaurant before me operated fine?

Either their cookline BTU was lower, or your engineer applied stricter NFPA 54 or AHJ tables. Gas line sizing is the most-frequent surprise upgrade in restaurant retrofits.

3. Do I really need a grease interceptor if I’m just doing a sandwich shop?

Yes in most U.S. cities. Even sandwich shops with deli slicers and toaster ovens generate FOG (fats, oils, grease) sufficient for code-required interception. Check local code; almost certainly yes.

4. Three-phase service is expensive — can I run my kitchen on single-phase?

Possibly, depending on your equipment list. Many restaurants run successfully on single-phase 400A service. If your spec includes a high-amp three-phase appliance (large electric oven, large mixer), single-phase isn’t an option. Confirm in load calculation.

5. What’s the most common MEP mistake operators make?

Skipping the early load calculation. Operators routinely sign leases on spaces that can’t economically support their concept’s MEP requirements. Always request the load calc before signing the lease, or contingent on it.

6. Can I install my own gas piping if I’m a licensed plumber?

In most jurisdictions, commercial gas requires a licensed gas-fitter (separate license from plumbing) or specifically endorsed plumber. Verify with AHJ. Doing your own is rarely worth the inspection risk.

7. Why does the floor sink have to be where the equipment manufacturer says?

Because indirect drain plumbing isn’t field-flexible — the floor sink must align with the drain stub on the equipment within a few inches. Coordinate cut sheets with plumbing rough-in. Fixing this after the slab is poured: $4,000–$15,000 retrofit.

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