Under the 2010 ADA Standards for Accessible Design (specifically Sections 308 and 309), electrical receptacles (outlets) must be mounted between 15 inches and 48 inches above the finished floor.
ADA guidelines for public spaces suggest a forward-reach light switch height between 15 and 48 inches. For a more accessible home, placing light switches at a maximum of 48 inches and outlets at a minimum of 15 inches from the floor is common. This allows for easier use from a seated position.
Standard outlet height
Outlets between 12 and 16 inches are positioned low enough to remain accessible without bending down or stretching but high enough to avoid sofas, beds, desks, or dressers.
Standard wall receptacle height is 1 foot from the top of the flooring to the bottom of the receptacle box, or 16 inches to the top of the box. Standard wall switch height is 4 feet from the top of the flooring to the bottom of the box.
THE 80% Rule
The National Electrical Code (NEC) by the National Fire Protection Association (NFPA) 80% rule is a guideline that recommends that circuit breakers should not be loaded to more than 80% of their rated capacity for continuous loads.
The NEC 125% rule for continuous loads means that when a branch circuit or feeder supplies a continuous load, the overcurrent device and related circuit design have to account for that load at 125% of the continuous portion, unless a specific 100%-rated assembly exception applies.
There aren't official height requirements outlined by codes like the National Electrical Code (NEC), but NEC 210.52. A. 2. states, “A common height for a wall outlet is between 12 to 16 inches to the bottom of the device.
Wall receptacles should be installed so that no point along the floor line of a wall is more than 6 feet (1829 mm) away from a receptacle. Wall receptacles should have 6 feet of wall space on each side of the receptacle, and this provides a maximum of 12 feet of wall space between the wall receptacles.
Electrical sockets must not be located too low to the floor so that it prevents the socket from being used by appliances or causes the appliance electrical cable to bend excessively. As a guide a minimum height of 400mm from the floor should be used.
2) Wall Counter Spaces (See Figure 1): a) A receptacle shall be installed for any counter that is 12 inches wide or greater; and, b) No point on the kitchen counter, measured at the wall may be more that 24 inches away from a receptacle. Also known as the 2ft. / 4ft.
The general rule in NEC® Section 240.24(A), without applying the exceptions, is that switches containing fuses and circuit breakers must be readily accessible and installed so that the center of the grip of the operating handle of the switch or circuit breaker, when in its highest position, is not more than 6 ft 7 in.
The range for side reach, like forward reach is 15″ to 48″ if unobstructed. The maximum reach depth for this range is 10″ measured from the available clear floor space.
Measure With a Drywall Square
Mark a line across four studs by running your pencil along the bottom part of the straightedge. Place the receptacles at this height. This gives you a height of 14 inches. If you then lay a floor, thus raising the floor level, you end up with a height of roughly 12 inches above the floor.
6'7” is maximum height unless a jurisdiction has an ADA requirement and the home or building is wheelchair accessible. No minimum. Generally, there is no minimum height. Maximum height is 6'7" to the highest breaker.
New dwellings
Both sources stipulate that socket outlets, switches and controls should be installed at a height between 450mm and 1200mm above the finished floor level. generally, this means it is a minimum of 450mm to the underside of an outlet and a maximum of 1200mm to the top of a switch or a control.
16” to center of the box for outlets, and 48” to center of the box for switches. There are no minimum requirements, you can put an outlet in the floor if you wish. There is a maximum though if said outlet is to be considered as one for required spacing.
NEC Section 210.52(a)(1) (aka 6'-12' rule): Receptacles shall be installed such that no point measured horizontally along the floor line of any wall space is more than 6' from a receptacle outlet..
Further, those outlets cannot be spaced more than 12 feet apart. This is to make sure that no point along the wall is more than 6 feet from an outlet. The rule makes a lot of sense because most appliances that a homeowner will plug in have 6-foot cords.
Standard Wall Outlets (Type A and B)
Type A outlets have two flat parallel slots, while Type B outlets include an additional grounding hole. These outlets are suitable for most household appliances, such as lamps, chargers, and small kitchen devices.
A 15-amp circuit is usually served by 14-gauge wire. It is protected by a 15-amp circuit breaker or fuse. 20-amp receptacles have a horizontal slot branching off one of the vertical slots. Appliances, such as microwaves, often have 20-amp plugs and must be plugged into a 20-amp outlet.
Electrical receptacle outlets on branch circuits of 30 amperes or less and communication system receptacles shall be located no more than 48 inches (1219 mm) measured from the top of the receptacle outlet box nor less than 15 inches (381 mm) measured from the bottom of the receptacle outlet box to the level of the ...
General wall outlets (near the floor)
Install at 30 cm from the floor. This ensures both safety and ease of use. Installing them too high might make it difficult to plug in floor-level appliances (such as vacuum cleaners or floor lamps). Too low height of installation could be unsafe in flood-prone areas.
The National Electrical Code (NEC) Section 210.52(C)(2) states that at least one GFCI-protected receptacle is required for kitchen islands with countertop spaces intended for food preparation or appliance use.