What does GFCI protection do and where is it required in my home?

GFCI (Ground Fault Circuit Interrupter) protection monitors the flow of electricity through a circuit and instantly shuts off power — within 1/40th of a second — if it detects that current is leaking to ground, which usually means it is flowing through a person's body. This technology has prevented thousands of electrocution deaths since its introduction, and the Ontario Electrical Safety Code requires GFCI protection in every location where water and electricity could come into contact.

A GFCI works by continuously comparing the amount of current flowing out on the hot wire to the amount returning on the neutral wire. In a properly functioning circuit, these two values are identical. If even a tiny difference is detected — as little as 5 milliamps, which is far below the threshold that can cause cardiac arrest — the GFCI trips and cuts power to the circuit. This happens so fast that it interrupts the current before it can cause serious injury. Without GFCI protection, a ground fault through your body could deliver a lethal shock before a standard breaker ever trips, because standard breakers are designed to protect wiring from overload, not people from electrocution.

Under the current Ontario Electrical Safety Code, GFCI protection is required in all bathrooms, all kitchen outlets within 1.5 metres of a sink, all outdoor outlets, all garage outlets, all unfinished basement outlets, and anywhere else that water and electricity may coexist. This applies to all new construction, renovations, and any time an outlet in these locations is replaced. Many older GTA homes — particularly those built before the mid-1980s across Toronto, Scarborough, North York, and the inner suburbs — have no GFCI protection at all, because it was not required when they were built. If your bathroom outlets are standard two-prong or three-prong outlets without test and reset buttons, they almost certainly lack GFCI protection.

GFCI protection can be provided in two ways: a GFCI outlet (the type with the test and reset buttons on the face) installed at the point of use, or a GFCI breaker installed in the panel that protects the entire circuit. Both approaches are code-compliant. A single GFCI outlet at the first position in a circuit can protect all downstream outlets on the same circuit, which is why you might have GFCI protection at outlets that do not themselves have test and reset buttons. Your electrician can advise on the most practical approach for your home.

You should test your GFCI outlets monthly by pressing the test button — the outlet should immediately lose power — and then pressing the reset button to restore it. If pressing test does not trip the outlet, or if it will not reset, the GFCI has failed and needs to be replaced. GFCI devices do wear out over time, and a non-functional GFCI provides zero protection. A GFCI outlet costs $15 to $25 for the device and $200 to $350 installed by a licensed electrician in the GTA, including wiring. Given that this device exists solely to prevent electrocution deaths, it is one of the most cost-effective safety upgrades available for any home. If your home lacks GFCI protection in required locations, Toronto Electrical Repair can connect you with a local licensed electrician to bring your outlets up to current safety standards.