Are exterior receptacles required at decks?  The 2008 edition of the National Electrical Code (NEC) describes two requirements for locations of outdoor receptacles in one- and two-family dwellings. The previous edition (2005) includes only one of these requirements, and inspectors should be aware of this change and understand the reason it was made. The NEC also describes how to achieve adequate weather protection for exterior receptacles.
 
Two Requirements for Locations of Outdoor Receptacles:

1.  As of 2005, the NEC required at least one outdoor receptacle in the front and in the rear of
     the house, not more than 6½ feet from the ground.
 
2.  As of 2008, the NEC added the following requirement:

    Balconies, decks and porches that are accessible from inside the dwelling unit shall have at least one receptacle outlet installed within the perimeter of the balcony, deck or porch. The receptacle shall not be located more than 6½ feet (2m) above the balcony, deck or porch surface.

    The code offers the following exception to this rule:

    Balconies, decks or porches with a usable area of less than 20 square feet (1.86 m2)
    are not required to have a receptacle installed.

     Clarifications:

        * The 2008 requirement is a supplement, not a replacement, to the requirements in effect in 2005. The 2008 NEC lists them both.

        * The newer requirement does not necessarily require installation of additional receptacles in new construction. Depending on the location of the balcony, deck or porch, a single receptacle may comply with both requirements.

        * InterNACHI inspectors should not call out the lack of exterior receptacles as a defect in houses that were built before the code was enacted.  Inspectors can recommend that receptacles be installed as a safety measure.

Reason for the 2008 Code Supplement:
 
Extension cords are likely to be used to run appliances on large balconies, decks and porches (greater than 20 feet square) if receptacles are not installed at these locations. Extension cords can be dangerous, especially if used outdoors and in wet conditions. The dangers associated with extension cords are…

    * structure fires. The Consumer Product Safety Commission (CPSC) estimates that extension cords cause 3,300 electrical fires every year in the United States. Common problems with extension cords that can lead to fires include:

         1. overloading. This can occur when the wire gauge is not sufficient to carry the electrical load; and
         2. short circuits. These occur where the current deviates from its intended path. For instance, if an extension cord becomes frayed, the hot and neutral wires may touch each other and the current would run down the wrong path.

    * electrical burns and shocks. These are commonly caused by using old or damaged extension cords with broken or frayed insulation. The insulative sheathing in extension cords may tear away and expose the live wires. Ultraviolet (UV) light, to which extension cords are exposed when they are used outdoors, can hasten this process.

    * tripping. Roughly half of the 4,000 injuries caused by extension cords annually in the U.S. are due to lacerations, sprains and contusions from tripping on the cords themselves.

Moisture Protection for Exterior Outlets

    * The receptacle’s faceplate must rest securely on the supporting surface to prevent moisture from entering the enclosure. If the receptacle is installed on uneven surfaces, such as stucco, stone or brick, a caulking compound can be used to fill in gaps.

    * All 15- and 20-amp, 120/240-volt receptacles installed outdoors must have a weatherproof enclosure. These receptacles must also have a while-in-use cover.

    * GFCI protection is required for all exterior receptacles, with the exception of this rare instance, as described by the NEC:

        GFCI protection isn’t required for a fixed electric receptacle supplied by a dedicated branch circuit, if the receptacle isn’t readily accessible and the equipment or receptacle has ground-fault protection of equipment.