What Does “14/2 With Ground” Mean?

Walk into any Toronto or GTA home renovation aisle and you will see coils of cable labelled with cryptic strings like “14/2 with ground” or “12/3 NMD90.” To an electrician those numbers describe the cable exactly. To a homeowner they can be intimidating. This guide translates “14/2 with ground” into plain English, explains what the numbers mean, and shows where each common variation is actually used in Ontario home wiring.

What does “14/2 with ground” mean?

“14/2 with ground” is a shorthand describing a cable with two 14-gauge insulated current-carrying conductors (typically one black hot and one white neutral) plus a bare copper ground conductor. It is the most common cable used for 15-amp 120V household lighting and receptacle circuits in Ontario. The Ontario equivalent is sold as NMD90 14/2 — non-metallic sheathed, dry-location, 90 °C-rated cable with two 14-gauge conductors plus a bare ground. Every home built in Ontario since the 1970s has miles of it in the walls.

Decoding the numbers

• First number (14): the American Wire Gauge (AWG) of the current-carrying conductors. Lower number = thicker wire. 14 gauge is standard for 15-amp circuits.
• Second number (2): the count of insulated current-carrying conductors. A “14/2” has two (hot + neutral). A “14/3” has three (hot + hot + neutral) and is used for multi-wire branch circuits or switched loops.
• “With ground” (or “WG” on some labels): the cable includes a bare copper ground conductor in addition to the numbered insulated conductors. This has been standard in Canadian residential cable for decades.
• NMD90: the Canadian standard identifier for indoor dry-location cable rated to 90 °C. See Romex, THHN, and UF wire.

Wire gauge cheat sheet for Ontario homes

• 14 gauge: 15-amp 120V circuits. Lighting, general receptacles, most bedrooms and living areas.
• 12 gauge: 20-amp 120V circuits. Kitchen small-appliance, bathroom, laundry, garage in modern installs.
• 10 gauge: 30-amp circuits. Electric dryer, water heater, some window ACs.
• 8 gauge: 40-amp circuits. Some ranges, some EV chargers.
• 6 gauge: 50-amp circuits. Larger ranges, hot tubs, higher-amperage EV chargers.
• 3 or 2 gauge (or larger): service entrance conductors, subpanel feeders.

Full context at what gauge wire is needed for a 15-amp outlet.

Conductor count: 2 versus 3

• 14/2: hot + neutral + ground. Standard 15-amp 120V circuit.
• 14/3: hot + hot + neutral + ground. Used for multi-wire branch circuits (two 120V circuits sharing a neutral), three-way switch travelers, or split-duplex kitchen counter receptacles.
• 12/2: 20-amp 120V circuit.
• 12/3: 20-amp multi-wire branch circuit or 240V circuit with a neutral component.
• 10/2: 30-amp 240V circuit without a neutral (some water heaters).
• 10/3: 30-amp 240V circuit with a neutral (electric dryers).
• 8/3: 40-amp 240V circuit with neutral, common for ranges.

Handle-ties on the panel side of a multi-wire branch circuit are covered at why are some breakers tied together with a handle tie.

Colour coding inside a Canadian NMD90 cable

Standard convention inside a Canadian residential cable:

• Black: hot (line) conductor.
• Red: second hot (line 2) in a 3-conductor cable, or a switched hot.
• White: neutral (grounded) conductor.
• Bare copper (or green in some conduit runs): equipment ground.

Any deviation is a code exception with specific rules (e.g., re-identified white for a switched loop). See what is the color code for house wiring and why is the neutral wire white and the hot wire black.

Where 14/2 is used in an Ontario home

• Bedroom and living-area receptacles.
• Interior lighting circuits.
• Bathroom fan on a 15-amp circuit (some jurisdictions).
• General-purpose 15-amp circuits throughout the home.

Areas that typically require heavier cable:

• Kitchen counter (12/2 or 12/3 for 20-amp small-appliance).
• Bathroom outlets (12/2 for 20-amp bathroom circuit — see Ontario bathroom rules).
• Laundry (12/2 for 20-amp receptacle).
• Dryer, range, and 240V loads (10/3, 8/3, 6/3 as appropriate).

What the cable jacket also tells you

The outer jacket of a spool of NMD90 usually prints:

• Cable type (NMD90).
• Conductor gauge and count (14/2, 12/3, and so on).
• Voltage rating (300V or 600V).
• Certification marks (CSA, cULus).
• Manufacturer name and lot number.
• Sometimes a date code or manufacturer part number.

All of this is stamped every few inches along the sheath so an inspector can verify at any accessible location.

Ampacity, breaker sizing, and the code

The Ontario Electrical Safety Code pairs each cable gauge with a maximum breaker size to protect the conductor from overheating:

• 14 AWG copper: 15-amp breaker max.
• 12 AWG copper: 20-amp breaker max.
• 10 AWG copper: 30-amp breaker max.
• 8 AWG copper: 40-amp breaker max.
• 6 AWG copper: 55-amp breaker max (per specific OESC provisions).

Upsizing a breaker beyond the wire’s ampacity is one of the most dangerous DIY moves. See can I replace a 15-amp breaker with a 20-amp breaker.

Expert tip from our ESA-licensed electricians

The single most confused label we see homeowners get wrong in GTA renos is 14/3. It looks like an upgraded 14/2, so people assume it is fine for anything 14/2 would handle. It is not — the extra conductor is a second hot for a multi-wire branch circuit or a three-way traveler, not extra ampacity. If you are ever uncertain what a cable in your home is, take a photo of the printed sheath and send it to your electrician before assuming. Cable labels never lie and they are the source of truth for what any circuit is actually rated for.

Related reading from ezsmart.ca

• What Is the Difference Between Romex, THHN, and UF Wire?
• What Is the Color Code for House Wiring?
• What Gauge Wire Is Needed for a 15-Amp Outlet?
• Can I Replace a 15-Amp Breaker with a 20-Amp Breaker?
• Why Are Some Breakers Tied Together With a Handle Tie?

Contact us

Not sure what cable is running in your Toronto or GTA walls or whether it matches the breaker it is on? Call ezsmart at 416-838-9006 or use our contact page. An ESA-licensed electrician will verify cable and breaker sizing.