What it usually means, the likely causes in order, what to safely try first, what a pro charges in Canada, and when to stop and call one.
This guide covers the common cases. Describe your exact problem and get a personalized diagnosis — free to start, with a DIY vs. call-a-pro verdict and a real cost estimate.
Power that works sometimes and not others - a light that cuts out when the switch is nudged, an outlet that dies and revives, a fixture that flickers back to life on its own - usually points to a connection that is almost made. Loose wires, worn switch or outlet contacts, and connections that expand and contract with heat all behave this way: fine when cold and untouched, open when warm, loaded, or vibrated. Intermittent faults are frustrating because they hide during a quick test, so the most valuable thing you can do before a visit is keep a precise log of when the power drops and what was happening at that moment.
A single intermittent outlet or light is usually not an emergency, but it should not be ignored for months. A loose connection that opens and closes can arc as it does so, which adds heat damage over time. Book promptly, and upgrade to urgent if intermittency arrives with buzzing, heat, a burning smell, sparking, or a breaker that starts tripping - that combination moves the symptom into the stop-and-call category.
The most common cause. A terminal or wire connector that is slightly loose makes contact until heat, load, or vibration shifts it, then opens. Back-stabbed outlet connections are frequent offenders in homes of a certain age. The fault often lives at the last working point before the dead one, not at the dead device itself.
Switches and outlets are mechanical devices with finite lives. Contacts pit and weaken until they only connect at certain angles or pressures. The signature is control by touch: the light responds when the switch is wiggled, pressed sideways, or held, and the outlet works only when the plug is propped at an angle.
Some faults appear only after minutes of running, when components warm up and expand, and vanish again once cooled. A failing fixture socket, driver, or ballast and a connection that opens when warm all fit this pattern. Timing matters: a fault that reliably arrives ten minutes after switch-on is giving you its diagnosis.
Before blaming the house, rule out the load. A cord with an internal break near the plug or strain relief cuts out when it moves and works when laid flat. If the intermittency follows one appliance to different outlets, the appliance or cord is the fault and the wiring is innocent.
| Job size | Typical estimate (CAD) |
|---|---|
| Simple fix — the straightforward version of this repair | $130–$280 |
| Major job — complex, hidden, or replacement-level work | $500–$2,500 |
Estimates only, calibrated to Greater Toronto Area trade rates and adjusted by region on this site — not a quote. Your exact price depends on the cause, parts, and access. A personalized diagnosis narrows this range using your specific symptom.
Your DIY tier here is excellent detective work: logging, swapping loads between outlets, checking cords, and confirming whether the fault is one point or a whole stretch. The repair itself - opening devices, remaking connections, replacing worn switches or outlets inside boxes - belongs to a licensed electrician, because the fault is by definition a connection problem in wiring you should not be handling live. Call a pro for any intermittency you cannot pin on a specific appliance cord, and call urgently if heat, noise, smell, or breaker trips join the pattern.
That means the outlet contacts no longer grip the plug blades firmly, or a wire connection behind it moves when the plug shifts. Propping works around the symptom while worsening the cause, because a poor contact under load generates heat and can arc. The outlet needs replacement by an electrician, not a better prop.
A heat-timing pattern like that suggests something opens as it warms: a connection expanding, a fixture component failing when hot, or a socket losing contact. When it cools, contact returns. Note the timing precisely and tell the electrician - a fault that can be predicted by the clock is much faster and cheaper to confirm on site.
Yes, indirectly. Temperature swings expand and contract connections, and damp weather can expose a marginal connection or an outdoor junction feeding indoor points. A fault that tracks cold snaps, rain, or humidity is a useful clue, not a coincidence, so include weather in your log when you notice a pattern.
It is better not to. Intermittent connections rarely improve on their own; the usual path is more frequent dropouts and increasing heat damage at the weak point. A prompt booking at normal rates is cheaper than the same fault after it has charred a device or started tripping breakers. If use is unavoidable meanwhile, avoid heavy loads on that point.
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