Identifying House Electric Wiring Colors | DoItYourself Identifying House Electric Wiring Colors By: 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.Author: DIY Staff[PDF] 9 Common Wiring Mistakes and Code Violations says, “If your house was built prior to 1987 or has 60°C wiring, consult a qualified elec-trician”? Wire is rated for the safe operating temperature of the conductors. Newer light fixtures are made with 90°C wires, which means the wire inside the fixture is rated to operate safely at temperatures up to 90°C.