Recessed pot lights (also called can lights or downlights) are the standard ambient lighting solution in modern Canadian homes. A typical living room or kitchen uses 6-12 lights to provide even ceiling-mounted illumination. The install involves cutting holes through ceiling drywall, running new wiring, and connecting to a switch — significant electrical work that requires an ESA permit in Ontario for any new installation.
This guide covers a same-room replacement (existing pot lights to new) or new-can-light installation in a finished ceiling. Note: new wiring requires a permit; like-for-like fixture replacement does not.
Before you start
Three things to settle:
1. Permit requirements. Like-for-like replacement of existing pot lights: typically no permit. Adding new pot lights, running new wiring, or modifying circuits: ESA permit required in Ontario. Working without required permits voids home insurance for related claims.
2. Pot light type and rating. IC-rated: insulation-contact rated, can be in direct contact with attic insulation. Required in residential ceilings with insulation above. Non-IC-rated: requires air gap from insulation. AT-rated: airtight, doesn't leak conditioned air into the ceiling cavity. AT/IC is the residential standard for Ontario.
3. New construction vs old work. New construction: housings install with brackets that screw to joists from above (when ceiling is open). Old work: 'remodel' or retrofit cans that install through a hole in finished drywall, with spring clips holding the can in place. Different products for different scenarios.
What you'll need
Tools
- Cordless drill with bits
- Hole saw matched to can size (typically 4 or 6 inch)
- Drywall saw (for irregular cuts)
- Voltage tester
- Wire strippers
- Phillips screwdriver
- Stud finder
- Step ladder
- Safety glasses
- Drop cloths (for ceiling debris)
Materials
- Recessed pot light housings (IC-AT rated for residential)
- LED retrofit modules or compatible LED bulbs
- Wire (12 or 14 AWG, matching circuit)
- Wire connectors
- Cable staples
- Trim rings (matching housing — white, brushed nickel, etc.)
- Drywall patch material (if any cuts need patching)
LED retrofit vs traditional pot light
Modern LED retrofit modules screw into pot light housings and provide much better efficiency and lifespan than traditional bulbs. They're 5-15W LED modules that produce 50-100W incandescent equivalent light.
If you're installing new pot lights, buy LED-integrated housings (LED is built into the housing, not a separate bulb). They're slightly more expensive upfront but eliminate bulb replacement for the life of the fixture (50,000+ hours).
Step-by-step instructions
Plan layout for even illumination
Standard spacing: 4-6 feet between pot lights for general ambient lighting. Closer for kitchen task areas (every 3-4 feet).
Lights should be at least 18 inches from walls (closer creates harsh angles).
Total count: room area in sq ft / 30 = approximate count. A 12x14 ft room (168 sq ft) needs roughly 6 lights.
Mark light locations and find joists
Measure and mark each light's location on the ceiling. Use painter's tape to mark — easy to adjust before cutting.
Use a stud finder to locate ceiling joists. Pot lights install between joists, so verify each marked location is in joist bay (not directly under a joist).
Adjust marks if needed to clear joists.
Turn off circuit and verify
If tying into an existing circuit, turn off the breaker and verify with a voltage tester at the existing junction box.
If running a completely new circuit (permit required), the new circuit's breaker is added at the panel — work on the panel only after a licensed electrician installs the breaker.
Cut ceiling holes
Use the hole saw to cut each marked location. Work slowly, supporting the cut piece so it doesn't fall.
Drywall dust falls heavily — wear eye protection and a dust mask. Drop cloths catch debris.
Inspect each hole for hidden obstructions (pipes, wires) before proceeding.
Run wiring through ceiling cavity
Pull NM cable (12 or 14 AWG) through the ceiling cavity from the existing junction box (or new circuit) to each pot light location.
Use cable staples to secure wire to joists.
Leave 8-12 inches of slack at each pot light location for connections.
Wire each pot light
At each light location, connect the cable to the housing's pre-attached wires:
- Black to black (hot)
- White to white (neutral)
- Bare copper or green to ground
- Use wire connectors. Pull-test to verify.
Install the housings
Old-work / remodel housings: insert through ceiling hole. Spring clips snap out and grip the back of the drywall, holding the housing in place.
New-construction housings: install before drywall, brackets screw to joists.
Verify housing sits flush with the ceiling surface (not protruding, not recessed).
Wire to switch and circuit source
At the switch location: connect the cable's other end to the switch.
At the circuit source (existing junction or new circuit): connect the wire to the source.
If running multiple lights on one switch: wire in parallel — each light's cable connects to a junction box where all are connected to a common feed.
Install LED modules and trim
LED retrofit modules: screw into the housing's socket. Most modern modules use a torsion spring or twist-lock mechanism.
Trim ring (the visible ceiling-side ring of the pot light): clip into the housing per the trim's instructions.
Restore power and test
Turn the breaker back on. Test the switch — all pot lights should turn on simultaneously.
If individual lights don't work: connection at that light is loose; verify wiring.
Test the dimmer if installed (LED-rated dimmer required for LED modules).
Schedule ESA inspection (for new installs)
If new wiring or new circuits were installed, schedule the ESA inspection per your permit. The inspector verifies wiring is to code before the work is closed up.
Don't drywall over inspection points — they need to be visible during inspection.
Common mistakes that cost you
- Skipping the permit. New wiring or circuits in Ontario require ESA permit. Working without one voids insurance for related claims.
- Wrong housing type for environment. Non-IC housings in insulated ceilings are a fire risk. Always use IC-AT rated for residential.
- Cutting through joists or pipes. Verify the cavity is clear before cutting. Use a stud finder and inspect with a flashlight before committing.
- Wrong dimmer for LED. LED needs LED-compatible dimmer. Mismatched produces flickering and shortened bulb life.
- Working without voltage check. Always verify power off with a tester. Working live causes injuries and fires.
Frequently asked questions
How many pot lights do I need?
Approximate formula: room area in sq ft / 30 = number of lights. A 12x14 ft room (168 sq ft) needs about 6 lights.
Adjust based on use: kitchens need denser spacing for task areas; bedrooms can be sparser.
Can I install pot lights without an attic?
Yes — old-work / remodel cans install through finished drywall. They have spring clips that hold them in place. The wiring runs through the ceiling cavity.
Without attic access, running new wiring is harder — sometimes requires snaking wire through the ceiling cavity from above (lift attic insulation if any).
What's IC-AT rating?
IC = Insulation Contact (housing can touch insulation safely). AT = Air Tight (doesn't leak conditioned air into the cavity).
Both are standard residential requirements. Older non-IC housings are obsolete for new construction.
Do I need a permit?
Replacing existing pot lights with same-rating new ones: typically no.
Adding new lights, running new wiring, modifying circuits: yes — ESA permit required in Ontario.
When to call us instead
Pot light installation across multiple rooms is often a permit-required project. We do this as part of full home renovations or as a standalone scope with permits and inspections coordinated.
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