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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.

$150–300 per GFCI/upgrade; whole-home grounding varies widelyAddress soonElectrical

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 $150–300 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

What is 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.

Why does it matter for home buyers?

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 can I 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."

How much does it cost to fix?

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

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. Casaroo reviews each guide against current pricing, code, and insurer practice. Cost ranges are 2026 estimates that vary by region, size, and access — confirm specifics with a licensed professional.
Related guides

Aluminum branch wiring

1965-73 wiring that's a fire risk at the connections — but usually a cheap fix.

$300–1,500Address before purchase

Knob-and-tube wiring

The pre-1950 wiring insurers flag — and why it's a before-you-buy issue.

$8,000–15,000+Address before purchase

Federal Pacific & Zinsco electrical panels

Failure-prone panels flagged for replacement no matter how fine they look.

$2,000–4,000Address before purchase

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