What Is a Rough-In Electrical Inspection?

Renovating a basement, finishing an addition, or wiring a new build in the GTA? At some point your contractor is going to schedule a rough-in inspection with the Electrical Safety Authority. This is the make-or-break checkpoint that decides whether the walls can close up or whether things get expensive. This guide explains exactly what a rough-in electrical inspection is, what the ESA inspector actually checks, how to prepare, and what happens if it fails.

What is a rough-in electrical inspection?

A rough-in electrical inspection is the stage of an ESA inspection that happens after all wiring, boxes, and cables are run but before the walls and ceilings are closed with drywall or insulation. An ESA inspector visits the site, verifies the work against the Ontario Electrical Safety Code, and either approves the rough or issues a defect notice that must be corrected before closing the walls. It is the last opportunity to fix wiring problems while everything is still visible.

Most residential renovations that add new circuits or move cable need this inspection. Panel changes, kitchen renos, basement finishes, additions, EV charger installs that involve new cable runs, and new construction all trigger it.

When the rough-in happens in the project timeline

The rough-in inspection sits between two major project milestones:

1. Wiring complete. All new cables run from the panel to the boxes. Boxes mounted. Wires pulled into boxes and left long. No devices installed. Panel changes wired to breakers if applicable.
2. Rough-in ESA inspection. Inspector visits, walks the site, marks findings, and either approves or issues a defect notice.
3. Insulation and drywall. Only after the rough-in is approved.
4. Devices installed, wiring terminated.
5. Final ESA inspection. Verifies terminations, devices, GFCI/AFCI function, and issues the Certificate of Inspection. See what is a Certificate of Inspection.

Closing walls before the rough-in passes is the single most expensive mistake a homeowner or contractor can make on a reno. If a defect is later found, that drywall comes back off.

What the ESA inspector actually checks at rough-in

The inspector looks at everything wiring-related that will soon be behind drywall. In our experience across the GTA, the specific items include:

• Cable type and gauge match the ampacity of each circuit.
• Cables are supported to code (proper stapling distance from boxes and along runs).
• Cables are protected where they cross studs or joists (nail plates where required, drilled at least 32 mm from the edge or the stud face is protected).
• Box fill is within limits for the number of conductors, devices, and cable clamps present.
• Boxes are mounted flush with the finished wall surface, or with an appropriate extension planned.
• Junction boxes are accessible and not planned to be buried in the wall. See can you splice wires outside of a junction box.
• Grounding conductors are continuous and correctly pigtailed.
• Circuit count and outlet spacing meet current OESC requirements.
• GFCI and AFCI coverage is planned for every required area.
• Wet-location and outdoor cable is the correct type (NMWU, UF, or equivalent).
• Bathroom and kitchen circuit counts and 20-amp requirements are respected.
• Panel is properly wired to code if included in this project.

The inspector is not looking at drywall, insulation, framing, or plumbing. Only the electrical work in its exposed state.

How to prepare for a rough-in inspection

1. Confirm all new cable is run and pulled into boxes with enough wire to work with.
2. Confirm every box is mounted at the correct height and depth and secured to a framing member.
3. Confirm every cable is stapled to code from box to first support and along the run.
4. Confirm nail plates are in place where required at drilled or notched studs.
5. Label circuits on cables at the panel so the inspector can trace them without a treasure hunt.
6. Have a printout of the project scope, the ESA notification number, and any load calculations available for the inspector.
7. Have a licensed electrician on site or reachable by phone during the appointment window.
8. Leave the panel accessible and, in cases where an inspection extension is required, ensure the deadfront is off if the contractor deems it necessary and safe.

A well-prepared site takes 20 to 40 minutes to inspect. A messy or under-labelled site can take twice as long and increases the chance the inspector misses context that would otherwise pass.

What happens if the rough-in fails

The inspector issues a written defect notice listing each item that failed. Your contractor corrects the items, sometimes without a reinspection required (for simple things like adding an extra staple), sometimes with a full reinspection (for more substantive issues). No drywall goes up until every listed item is resolved and the rough-in is approved.

Common rough-in defects we see across the GTA:

• Missing nail plates on cables drilled too close to a stud edge.
• Insufficient cable support (too few staples).
• Overfilled boxes for the number of conductors.
• Wrong cable type for a wet or outdoor location.
• Missing or discontinuous ground conductor.
• Insufficient outlet spacing along a wall. See what is the code requirement for outlet spacing.
• Buried junctions planned inside walls.
• Bathroom or kitchen circuit count below current OESC requirements.

Why the rough-in inspection matters

Three reasons the rough-in checkpoint exists:

• Visibility. Once drywall is up, verifying that a cable was correctly stapled or that a box is not over-filled becomes destructive. Rough-in verification is the only cost-effective time to check.
• Safety. Behind-the-wall defects cause the invisible failure modes — hidden arcs, buried splices, missing grounds — that lead to house fires years later.
• Documentation. The rough-in step feeds directly into the Certificate of Inspection issued after final. Skipping or faking it means no valid COI at the end.

For a broader picture of what an ESA inspection covers overall, read what happens during an ESA electrical inspection.

Expert tip from our ESA-licensed electricians

The single biggest reason rough-ins fail in the GTA is not electricians being sloppy — it is drywallers being ahead of schedule. We have seen homeowners let the drywall crew start closing walls the day before the ESA visit because “it looked ready.” It never is. Even one closed wall means the inspector cannot see part of the system, and every hidden junction becomes an assumption. Hold the drywall crew until you have the rough-in approval in writing. It is the cheapest scheduling discipline you can enforce and it saves the most money on any reno you will ever run.

Related reading from ezsmart.ca

• What Happens During an ESA Electrical Inspection?
• When Do I Need an ESA Inspection During a Renovation?
• What Is a Certificate of Inspection and Why Does It Matter?
• What Is the Code Requirement for Outlet Spacing?
• When Do I Need an ESA Permit for Electrical Work?

Contact us

Planning a renovation in Toronto or the GTA and want a licensed electrician to handle the rough-in and pass ESA the first time? Call ezsmart at 416-838-9006 or use our contact page. We file the notification, coordinate the inspection, and stand on site while it happens.