Identifying House Electric Wiring Colors | DoItYourself Standard Colors Used for Home Wiring. What follows here is the standard coloring for wires throughout a home. The gauge or size of the wire may change depending on the current flowing through the circuit, but the color is a consistent feature. Wiring Color Codes | Color Codes | Electronics Textbook UK AC power circuit wiring color codes. US, AC:The US National Electrical Code only mandates white (or grey) for the neutral power conductor and bare copper, green, or green with yellow stripe for the protective ground. In principle any other colors except these may be used for the power conductors.