A power outlet box encloses wire connections, helping protect against short circuits. They can contain light switches or receptacles. The National Electric Code (NEC), as well as local building codes, regulates the types of outlet boxes allowed in each type of application.
Different situations require different types of boxes. A handy box functions as both a light switch and outlet box, while a junction box allows circuits to split. A new work box goes in new construction sites before applying drywall, while an old work box goes on pre-existing walls. An outdoor box protects wiring from the elements.
Different options of outlet boxes include standard rectangular, Decora, blank, single gang, and a double gang, or square box. For fixtures such as a ceiling fan or a heavy lighting fixture like a chandelier, use a ceiling box. A power outlet box needs a proper cover (don’t cover it with drywall or paneling) and enough space for the conductors inside. The covers you choose must match the style of the electrical box.