SFB-6 — Dwelling-Unit Required Circuits and Outlet Placement

Exam checkpoints

Start with required 20-ampere circuits

A dwelling layout problem has two layers: provide the required branch circuits, then place the required outlets. Under 2017 NEC 210.11(C)(1), at least two 20 A small-appliance branch circuits must supply the receptacle outlets specified by 210.52(B). They serve kitchen, pantry, breakfast room, dining room, or similar area wall and floor receptacles, countertop receptacles, and refrigeration equipment within the rule.

Section 210.52(B)(2) generally prohibits other outlets on these small-appliance circuits. Stated exceptions permit items such as a clock receptacle and receptacles supplying supplemental equipment and lighting for gas-fired ranges, ovens, or counter-mounted cooking units. A refrigerator may be supplied by one of the small-appliance circuits or by an individual branch circuit rated 15 A or more under the exception in 210.52(B)(1). Do not convert an exception into permission to supply general kitchen lighting.

Section 210.11(C)(2) requires at least one additional 20 A branch circuit for the laundry receptacle outlet or outlets required by 210.52(F), and that circuit has no other outlets. Section 210.11(C)(3) requires at least one 20 A branch circuit for bathroom receptacle outlets. It generally supplies no other outlets, but where it supplies a single bathroom, other equipment in that same bathroom may be supplied in accordance with 210.23(A)(1) and (A)(2).

The 2017 edition also includes 210.11(C)(4): at least one 120 V, 20 A branch circuit supplies the garage receptacle outlets required by 210.52(G)(1) in attached garages and detached garages with electric power. That circuit has no other outlets, except it may supply readily accessible outdoor receptacle outlets. These required circuits are minimums; calculated load or equipment instructions can require more.

Apply the general wall-space rule

Under 210.52(A)(1), receptacle outlets in kitchens, family rooms, dining rooms, living rooms, parlors, libraries, dens, sunrooms, bedrooms, recreation rooms, and similar rooms are placed so no point measured horizontally along the floor line of a wall space is more than 6 ft from a receptacle. This creates a maximum 12 ft spacing only on an uninterrupted straight wall when a receptacle can serve 6 ft in each direction. Begin at each break, doorway, or similar interruption rather than applying “12 ft apart” blindly.

Section 210.52(A)(2) defines wall space to include any space 2 ft or more wide, space occupied by fixed panels in exterior walls, and fixed room dividers such as freestanding counters or railings. Sliding panels do not automatically erase the wall space. Under 210.52(A)(3), a floor receptacle counts for wall-space coverage only when it is within 18 in. of the wall.

Receptacles installed more than 5.5 ft above the floor generally do not count toward the 210.52 requirements. Neither do receptacles that are part of a luminaire or appliance or are located within cabinets or cupboards, except as a specific rule permits.

Lay out kitchen countertop receptacles

Under 2017 NEC 210.52(C)(1), each wall countertop space 12 in. or wider requires receptacle outlets so no point along the wall line is more than 24 in. horizontally from a receptacle. On an uninterrupted countertop, this commonly produces a maximum 4 ft spacing. Ranges, sinks, and refrigerators can divide countertop spaces under the rule; measure each qualifying space separately.

Sections 210.52(C)(2) and (C)(3) require at least one receptacle for each qualifying island and peninsular countertop space with a long dimension of at least 24 in. and a short dimension of at least 12 in. For a peninsula, the long dimension is measured from the connecting edge. These are the 2017 dimensional rules; do not import later countertop-area calculations.

Under 210.52(C)(5), countertop receptacles generally cannot be more than 20 in. above the countertop. Below-counter placement is permitted only for specified construction and location conditions, including limits related to distance below and countertop overhang. Face-up receptacles in countertops and similar work surfaces must comply with the applicable receptacle installation rule; ordinary devices are not made suitable by a weather-resistant cover.

Check the room-specific outlets

Section 210.52(D) requires at least one bathroom receptacle within 3 ft horizontally of the outside edge of each basin. It can be on an adjacent wall, partition, basin countertop, or qualifying listed assembly within the permitted location. The rule establishes a maximum distance, not a minimum separation from the basin.

Section 210.52(E) requires outdoor receptacles at the front and back of a dwelling, accessible from grade and not more than 6.5 ft above grade. A balcony, deck, or porch attached to the dwelling and accessible from inside also needs at least one receptacle accessible from that space and not more than 6.5 ft above it; the 2017 text does not impose a minimum area threshold. Section 210.52(F) requires at least one receptacle in a laundry area, subject to its dwelling exceptions.

Under the 2017 garage rule in 210.52(G)(1), at least one receptacle is installed in each vehicle bay and not more than 5.5 ft above the floor. Each separate unfinished basement portion requires at least one receptacle under 210.52(G)(3), in addition to a receptacle for specific equipment. Hallways 10 ft or more long need at least one receptacle under 210.52(H). A foyer exceeding 60 ft² uses 210.52(I), which requires receptacles in qualifying wall spaces 3 ft or more wide.

Finally, 210.70 supplies lighting-outlet rules for habitable rooms, bathrooms, hallways, stairways, attached garages, detached garages with power, and outdoor entrances. A switched receptacle can satisfy specified lighting rules in some rooms but not every location. After placement, separately check circuit source, receptacle rating, GFCI, AFCI, equipment instructions, and accessibility.