Room Wiring Requirements Guide
Receptacle spacing, required circuits, GFCI and AFCI by room and code edition — with the difference between the two protections made plain.
Circuits required
GFCI and AFCI are not interchangeable
They are different devices for different hazards, and this is the distinction people get wrong. A GFCI protects people: it compares current going out against current coming back and trips at about 5 milliamps of difference, the level at which current leaking through a person becomes dangerous. An AFCI protects property: it listens for the electrical signature of arcing — a loose terminal, a nail through a cable, a chewed cord — and trips before that arc starts a fire. It does nothing whatever about shock. Plenty of circuits need both, which is exactly why dual-function devices are sold.
- The 6-foot rule is about cord length. "No point more than 6 ft from a receptacle" exists so anything with a standard 6 ft cord reaches one without an extension lead. Extension leads under rugs and behind furniture are what the rule is preventing — worth more to know than the number.
- The code edition changes the answer. The 2020 cycle added every basement receptacle and every kitchen receptacle rather than just the countertop ones. An older install is compliant as built and does not become illegal, but new or extended circuits are held to the current edition.
- These are minimums. More receptacles are always permitted and usually a better idea — an extra box during a rough-in costs almost nothing against an extension lead you live with for twenty years.
- Adoption lags publication by years, and local amendments are common. The edition selected here may not be the one your inspector works from.
A planning reference, not a code citation. Ask the authority having jurisdiction before relying on any of it, and have a licensed electrician do the work where you are not certain.
How to use
- Pick the room and the code edition your area has adopted.
- Enter the wall perimeter, and the countertop run for a kitchen.
- Read the minimum receptacle count and the spacing rule behind it.
- Check GFCI and AFCI separately — they are different protections.
Frequently asked questions
What is the difference between GFCI and AFCI?
They protect against completely different things. A GFCI protects people: it compares current flowing out against current returning and trips at about 5 milliamps of imbalance, which is roughly the level at which current leaking through a person becomes dangerous. An AFCI protects property: it listens for the electrical signature of arcing, such as a loose terminal or a nail driven through a cable, and trips before the arc starts a fire. Neither substitutes for the other, and many circuits need both, which is why dual-function devices are sold.
Why must receptacles be no more than 12 feet apart?
Because the actual rule is that no point along the floor line may be more than 6 feet from one, and receptacles every 12 feet achieve that. The purpose is cord length: anything with a standard 6 foot cord should reach an outlet without an extension lead. Extension leads running under rugs and behind furniture are the hazard the rule exists to prevent, which is more useful to understand than the number itself.
Does my basement need GFCI protection?
Under the 2020 edition and later, yes — every receptacle, finished or unfinished. Before 2020 it applied only to unfinished areas, which is why an older finished basement was compliant when built and would not be today. Existing work does not become illegal, but any new or extended circuit is held to whichever edition your jurisdiction has adopted, and adoption varies by years between areas.
How many receptacles does a kitchen countertop need?
Enough that no point along the counter is more than 24 inches from one, so they sit at most 48 inches apart, and any counter section 12 inches or wider needs at least one. That is separate from the wall receptacles, which follow the ordinary 12 foot rule — a kitchen needs both, not whichever is larger. From the 2023 edition an island receptacle must be within the countertop space itself rather than mounted underneath it.
What can the kitchen small-appliance circuits feed?
Receptacles, in the kitchen, pantry, breakfast room or dining room, and nothing else. Two 20 amp circuits are the minimum. They may not supply lighting, the dishwasher, the waste disposal or anything hard-wired. This is the rule most often broken in practice, usually by adding the dishwasher to a counter circuit during a remodel, and it is one an inspector will look for.
Do bathrooms need AFCI as well as GFCI?
GFCI always, AFCI generally not. NEC 210.12 lists the rooms requiring arc-fault protection and bathrooms are not among them, nor are garages or outdoor areas. That is a deliberate distinction rather than an oversight: those spaces carry a high shock risk and a comparatively low fire risk from concealed wiring. Some jurisdictions amend it, and a dual-function device is never wrong.
Are these numbers the maximum or the minimum?
The minimum, in every case. Nothing in the code prevents more receptacles, and more is usually the better choice — an extra box during a rough-in costs a few pounds against an extension lead you will live with for twenty years. Treat everything here as a planning reference rather than a code citation, since local amendments are common and the authority having jurisdiction is what actually governs.
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