Rough-In
Rough-in is the construction phase during which the mechanical, electrical, and plumbing (MEP) systems are installed inside walls, ceilings, and floors — before drywall, tile, or finishes cover them. Inspections occur at rough-in to verify code compliance before the work is concealed. Rough-in establishes the functional skeleton of a building's systems.
Updated July 13, 2026
Key Facts
- 1Rough-in inspections must be passed before drywall installation — skipping inspections creates major problems at certificate of occupancy
- 2Plumbing rough-in for a full-service restaurant with a commercial kitchen typically costs $18,000–$45,000 before fixtures are added
- 3Electrical rough-in includes running conduit, pulling wire, and installing boxes — but not covers, fixtures, or panels, which come in the trim-out phase
What Happens During Rough-In
Rough-in work begins after framing is complete and before drywall is hung. Plumbers install drain lines, vent stacks, and supply pipes at the locations specified in the construction drawings. Electricians run conduit and pull wire from the panel to all outlet, switch, and fixture locations. HVAC technicians install ductwork and equipment in the ceiling cavity.
The sequence matters: plumbing typically precedes electrical because drain lines and vents need specific slope and routing that electrical must work around. HVAC ductwork is often coordinated simultaneously with both.
Rough-In Inspections
Before walls are closed, the building inspector must approve the rough-in work for plumbing, electrical, and mechanical systems. These are separate inspections that must each be passed and documented. Failing a rough-in inspection — or missing it entirely and closing walls before inspection — can require opening walls after the fact, which adds significant time and cost.
For commercial projects, rough-in inspections are typically conducted by the local building department with input from the fire marshal (for fire suppression systems) and the health department (for food service projects).
Frequently Asked Questions
What is the difference between rough-in and trim-out?
Rough-in installs the systems inside walls and ceilings before surfaces are closed. Trim-out (or finish work) is the final phase after walls and floors are finished — installing fixtures, covers, devices, and equipment at the locations established during rough-in.
How long does rough-in take for a restaurant buildout?
For a typical 1,500–2,500 sqft restaurant with a full commercial kitchen, rough-in work (plumbing, electrical, HVAC, and fire suppression) typically takes 3–6 weeks. Complex kitchens with extensive gas, plumbing, and electrical requirements can take longer.
Can rough-in be done without a permit?
No. Commercial rough-in without permits is illegal in all U.S. jurisdictions and creates significant liability. If discovered, unpermitted work must be demolished, rerouted, and re-inspected at your expense — plus potential fines.