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🍁 Built for Canadian homes — written to the Canadian Electrical Code and provincial rules. Not intended for use outside Canada.
DRAFT — this page has not yet been reviewed by a licensed professional. Editorial preview only.

Lights are flickering

Flickering lights are usually a bulb or a dimmer, not a wiring disaster. One pattern matters more than the rest: if the whole house flickers at once, skip ahead — that one deserves a prompt call.

tuneWhat are you noticing?
Select anything that matches and the checklist below reorders to fit. Not sure? Skip it.
emergency_home

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Start here

In Canadian homes, start with the bulb. Switch the light off, let the bulb cool, snug it in its socket, and try again. Still flickering? Swap in a bulb you know works. If the fixture is on a dimmer and the bulb is an LED, check the package or bulb base for the word "dimmable" — a non-dimmable LED on a dimmer flickers by design.

Ranked from real-world failure data. The order updates as you select what you’re noticing above.

Likely causes, in the order to check them

Showing the typical order
Beginner-friendly Doable, with care Safety-critical Call a pro

visibilityHow to check

  1. Switch the light off and let the bulb cool for a minute, then snug it gently in its socket — a quarter-turn is often the whole fix.
  2. Still flickering? Swap in a bulb you know works from another fixture. If the flicker stops, the old bulb was the cause.
  3. If the fixture is on a dimmer, check the bulb or its package for the word "dimmable". A non-dimmable LED on a dimmer will flicker or shimmer, especially at low settings — that's a mismatch, not a fault in your wiring.
buildNo tools schedule5 min

handymanHow to fix it

Reseat or replace the bulb. If the fixture is on a dimmer, buy an LED marked "dimmable" — and if flicker persists at low settings, choose a bulb listed as compatible with your dimmer model (manufacturers publish compatibility lists).

  1. Switch off the light and let the bulb cool before handling it.
  2. Snug the bulb in its socket; if it's visibly darkened at the base or rattles, replace it.
  3. On dimmed fixtures, fit a dimmable LED. Match the base (usually E26 medium in Canada) and, for stubborn shimmer, pick a bulb from the dimmer maker's published compatibility list.
schedule10 min savings$5–25
Dimmable LED bulbMatch the base (usually E26 in Canada) and look for "dimmable" on the package; for stubborn shimmer, use the dimmer maker's compatibility list

visibilityHow to rule it in (without opening anything)

  1. Put a known-good bulb in the flickering fixture. If the flicker continues with a good bulb, the bulb is ruled out.
  2. Notice the pattern: does the flicker respond to footsteps, a door closing, or jiggling the switch? Vibration-sensitive flicker points to a loose connection.
  3. Check whether other lights on the same circuit flicker too. One fixture or one circuit — with good bulbs — points to a loose joint at that fixture or its switch. Stop there: that's your free rule-in, and the repair belongs to a licensed electrician.
buildNo tools schedule10 min

verifiedWhy this one goes to a pro

Finding a loose connection means opening boxes and handling conductors that may be live or mis-wired, and a joint remade badly keeps making heat inside your wall. This is exactly the kind of small, quick job electricians do every week — the visit is short and the peace of mind is real.

Your notes travel with the request — what you saw, what you ruled out, when it started — so the pro arrives with a head start instead of a mystery.

visibilityHow to recognize it

  1. Next time the lights dip, note what else just happened. Furnace blower, AC compressor, dryer, or a space heater starting at the same moment is the signature.
  2. Judge the dip honestly: a brief, slight dim that recovers in under a second is normal in most Canadian homes — big motors gulp current at start-up.
  3. It stops being normal if the dips are new, noticeably deep, happen with small loads, or are getting worse over time. Those patterns are worth an electrician's look — they can point to an undersized circuit or a loosening connection upstream.
buildNo tools schedule5 min

handymanWhen it's normal — and when it isn't

A brief, slight dim when a big motor starts usually needs no fix at all. If dips are deep, new, or worsening, an electrician can check for loose connections and measure the voltage drop; a persistent culprit appliance (like an AC) can sometimes get a dedicated circuit or a hard-start kit. Honest answer: many homes simply live with a small blink.

visibilityHow to check

  1. Run the dimmer through its range. Flicker that appears at certain brightness levels — especially low ones — points to the dimmer (or an LED–dimmer mismatch; rule the bulb out first).
  2. Listen and feel: a buzz from the switch, or a switch plate that feels warm to the touch, points to a dimmer working too hard or wearing out. Warm is a clue; hot, or any burning smell, means switch it off and call an electrician.
  3. Try a dimmable LED you know is compatible. If a good, compatible bulb still flickers through that switch, the dimmer is the prime suspect.
buildNo tools schedule5 min

handymanReplacing the dimmer

report Two rules before you open the switch boxFirst: breaker off and proven dead with a non-contact voltage tester — switch boxes can contain wires from more than one circuit, so test every wire. Second: check your province's rules; in Quebec this work is reserved to licensed electricians, and other provinces may require a permit. If either rule gives you pause, this is a quick, inexpensive job for an electrician.

Turn off the breaker, verify the box is dead with a non-contact voltage tester, photograph the wiring, and swap in an LED-compatible dimmer wire-for-wire. Check your province's rules first — in some provinces this is licensed or permit work (see the legality notes on this page).

  1. Turn off the circuit at the breaker panel — not just the switch — and put tape over the breaker so nobody flips it back.
  2. Remove the switch plate and confirm the box is dead with a non-contact voltage tester on every wire. No tester, no job.
  3. Photograph the wiring, then disconnect the old dimmer and connect the new LED-compatible dimmer wire-for-wire per its instructions.
  4. Fold the wires back neatly, mount, restore power, and run the dimmer through its full range with your bulbs installed.
schedule30 min savings$15–60
LED-compatible dimmer switchMatch single-pole vs 3-way to your old dimmer, and check it's rated for LED loads
gavel Check your province first AB: permit + inspection required · BC: permit + inspection required · ON: permit + inspection required · PE: permit + inspection required · QC: licensed professionals only
National default shown conservatively as licensed-only; electrical rules are provincial — REVIEW: replace with verified per-province rows before publish.

verifiedWhy this one goes to a pro

A loose service neutral puts abnormal voltage on circuits all over the house and can overheat connections until they burn. Everything past noticing the pattern belongs to your utility or a licensed electrician — the service entrance can remain live even with your main breaker off. Your whole job is the phone call, made today.

Your notes travel with the request — what you saw, what you ruled out, when it started — so the pro arrives with a head start instead of a mystery.

sort

Why the list is in this order

We don’t sort by likelihood alone. We sort the way a good, honest tradesperson thinks: rule out the free, safe, common causes first. That’s why the cheap checks outrank the expensive repairs — and why anything dangerous gets a hard stop instead of a pep talk. The order exists to save you money, not to sell you anything.