An electrical code is an official set of guidelines that specifies how various aspects of an electrical system should be installed. Most local residential electrical codes are based on the NEC—the National Electrical Code—a model code that provides guidelines on which local communities can model their own residential codes.
Among other wiring installation details, the electrical code specifies how electrical outlets should be spaced and which types of outlets to use in general living areas, in bathrooms, in kitchens, and in other locations. Far from being arbitrary, the electrical code as it relates to outlets is imminently practical.
One prime example of this is with outlet spacing. In the kitchen, countertop outlets should be no farther than 48 inches away from each other. This spacing is based on the average length of electrical cord found on most small kitchen appliances. The intent is to prevent homeowners from stretching cords too far and creating hazards.
Code requirements for residential wall outlets may differ from one community to another since model building codes can be adopted and adapted as a community sees fit. Most, but not all, follow the recommendations of the national model code, the NEC. Be sure to check with your local building permit department for particulars.
Watch Now: Electrical Code for Outlets in the Home
Outlet Spacing in General Living Areas
For code purposes, "general areas" are defined as rooms such as living rooms, family rooms, bedrooms, and hallways. In these spaces, wall outlets should be spaced no farther than 12 feet apart. This spacing is chosen so that a lamp, computer, television or other appliance will never be more than 6 feet away from an electrical outlet.
Spacing outlets more frequently than every 12 feet is, of course, allowed, but it is not required by code. If the space receives heavy use, such as with people charging phones or plugging in laptops, shorter spacing between outlets may be a good idea.
One exception to the rule specifying 12-foot placement of outlets: If the wall is less than 24 inches wide, an outlet is not required. Again, you are allowed to place an outlet in this space if you so choose.
Hallways more than 10 feet long must have at least one electrical outlet, preferably at the mid-point.
Outlet Spacing in Bathrooms
On bathroom walls, there must a receptacle at least within 3 feet of the outside edge of the sink basin. Generally, it is desirable to install the outlet above the countertop. But the code's 3-foot designation provides leeway in case this is not possible or practical.
Outlet Spacing in Kitchens
In kitchens, electrical outlets should be placed no farther than 48 inches apart, so that no point on the countertop is more than 24 inches away from a receptacle. Any countertop 12 inches wider or more should have an outlet on the wall behind the countertop. Outlets should not be positioned higher than 20 inches above countertops, with certain exceptions for physically disabled persons and for islands or peninsulas where this height rule cannot be met.
Amperage of Outlet Receptacles
General-purpose outlet receptacles should have a rating that is appropriate for the amperage of the circuit they serve. Generally, these household circuits will provide 15-amps or 20-amps of service, and the outlet receptacle rating should not exceed this amperage. Check the circuit's breaker in the service panel to find out whether it is 15 amp or 20 amp service, and choose receptacles appropriate to that rating.
There is no danger to installing 15-amp outlet receptacles on a 20-amp circuit (in fact, this is the standard practice), but under no circumstances should a 20-amp receptacle be installed on a 15-amp circuit. A 20-amp receptacle is designed to accept the special plug on heavier-use appliances, and if such an appliance plugs into a 15-amp circuit, there is a danger of drawing too much power and overloading the circuit. A 20-amp receptacle is only installed on a 20-amp or larger circuit, and it is generally reserved for locations where a heavy-duty appliance is typically used, such as an outlet that might power a space heater.
As an additional safety measure, most municipalities now require tamper-resistant outlets for general areas of the home. These outlets are identified by the recessed letters "TR" on the face of the outlet. In tamper-resistant outlets, a spring-loaded gate within the outlet prevents young children from pushing objects such as knives into the outlet slots.
Tamper-resistant outlet receptacles are usually are not required:
- For outlets located 66 inches or more above the floor
- For outlets behind large appliances that are difficult to move (such as a refrigerator)
- For outlets that are part of a light fixture or appliance
GFCI Protection Requirements
The electric code requires that outlet receptacles have GFCI (ground-fault interrupter) protection in certain areas of the home, including:
- Receptacles over countertops in kitchens
- Receptacles powering dishwashers
- Receptacles in bathrooms
- Receptacles in laundry areas
- Receptacles in unfinished basements
- Receptacles in garages and other accessible outdoor locations
- Receptacles near swimming pools, spas, and other water features
GFCI protection seeks to lower the risk of shock when ground faults occur, and it can be provided in one of two ways: through the use of special GFCI circuit breakers that provide protection to the entire circuit; or with GFCI receptacles, which are specially designed to provide GFCI protection to a specific outlet, or to that receptacle as well as "down-stream" receptacles that are part of the same circuit.
Requirements for GFCI protection have gradually expanded with successive revisions to the NEC, and those requirements could possibly expand further in the future.
AFCI Protection Requirements
Since January 1 of 2014, the NEC has also required a different kind of protection for all 15-am and 20-amp receptacles in general living spaces. This requirement calls for AFCI (arc-fault circuit-interrupter) protection for these receptacles. AFCI protection seeks to sense and shut down a circuit when an arc fault—minor sparking between wires or wire connections—occurs. AFCI protection reduces the chance of fire due to this sparking.
AFCI protection can also be provided in one of two ways: through special circuit breakers that protect all receptacles and devices along the circuit; or through special AFCI outlet receptacles that offer protection to one location only. Standard practice is to install AFCI circuit breakers to protect the entire circuit, but individual AFCI receptacles can be installed where circuit breaker installation is not practical.