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Ungrounded outlets & missing GFCIs

Two related electrical-safety items. Ungrounded outlets, two-prong receptacles, or three-prong ones with no actual ground wire behind them, lack the safety path that protects you and your electronics. GFCIs (ground-fault circuit interrupters) are the outlets with test and reset buttons that compare current flowing out and back and cut power in milliseconds if even ~5 milliamperes leaks to ground, for example through water, or through you. Under the Canadian Electrical Code, GFCI protection has been required in bathrooms for decades and is required for receptacles within 1.5 m of a sink, plus outdoors, garages, and similar wet locations.

$150 to $300 per GFCI/upgrade; whole-home grounding varies widelyAddress soonElectrical
The quick answer

Two-prong (ungrounded) outlets and missing GFCIs near water are real shock hazards, but usually cheap fixes, about $150 to $300 per GFCI. The bigger tell: widespread ungrounded outlets in an older home can point to knob-and-tube or aluminum wiring underneath, which is the thing to rule out. A $5 outlet tester reveals an open ground; an electrician confirms what's behind it.

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The ten second check

What else is typical in a house this age?

You are reading the ungrounded outlets & missing GFCIs page. Type the year the house was built and I will tell you what else tends to be true at that age, what it costs, and what to ask. One number, ten seconds.

A guess is fine. 1965, or just the 60s.

Anything worrying you? Tap any that apply, or skip it.

Free. No account. Educational and impartial, not a home inspection.

Why it matters

Missing grounding and missing GFCIs near water are real shock hazards, and the CPSC recommends testing GFCIs monthly because they do wear out. On their own these are usually inexpensive fixes, but in an older home, widespread ungrounded outlets are often a clue to bigger wiring issues (knob-and-tube or aluminum branch wiring), which is the more important thing to rule out.

How to spot it

Two-prong outlets; three-prong outlets in a pre-1965 home with no rewire record; and the key one, no test/reset buttons on the outlets beside a kitchen or bathroom sink, in the garage, or outside. A $5 plug-in outlet tester will reveal an "open ground."

What it costs

Roughly $150 to $300 to add a GFCI or remediate an outlet; whole-home grounding depends entirely on the wiring behind the walls and can be far more.

What to do

Address soon. An electrician can add GFCIs quickly. If ungrounded outlets are throughout an older home, have them check for knob-and-tube or aluminum branch wiring (see those guides) before you assume it's a small job.

Education and triage, not a home inspection. Casaroo flags ungrounded or missing-GFCI outlets from your photos, a licensed electrician confirms what's behind them.

Common questions

Is an ungrounded outlet a big deal?

On its own it is an inexpensive fix at $150 to $300 per outlet. What matters more is what widespread ungrounded outlets in an older home can point to, which is knob-and-tube or aluminum branch wiring behind the walls. Rule those out before you assume it is a small job.

How do I test for this myself?

A five-dollar plug-in outlet tester will reveal an open ground. The other check needs no tools: look for test and reset buttons on the outlets beside a kitchen or bathroom sink, in the garage, and outdoors. No buttons means no GFCI protection where the code requires it.

Do GFCIs wear out?

Yes, which is why the CPSC recommends testing them monthly with the test button. A GFCI that does not trip when tested is not protecting anything.

Someone put three-prong outlets on ungrounded wiring. Is that legal?

It is a common and misleading shortcut, because the outlet looks grounded and is not. Have an electrician confirm what is actually behind them rather than trusting the face of the receptacle.

Sources

GFCI rules follow the Canadian Electrical Code as adopted provincially; a licensed electrician confirms. Casaroo flags, it does not inspect.

Last reviewed 2026-06-27. This guide is general education, not a home inspection and not advice for your specific property. Always consult the appropriate licensed professional, and get a licensed home inspection before you remove conditions or buy. Cost ranges are 2026 estimates that vary by region, size, and access; confirm specifics with a qualified professional.
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