In a typical switch loop (from the past) where 14/2 is used, the white wire should be marked on both ends with black tape to indicate it is a "hot" wire just like the black wire.
In a 14/3 cable, the black and red would be used for the switch and the white remains the neutral to be used in the switch box if it's ever needed (now required by code). Is the red wire being red good enough to indicate that it's "hot", or should it also be marked with black tape to indicate it is actually the switched side of the black wire?
For the answer – is this codified, or just convention?
Best Answer
Being red is fine. Code wise, anything that's not colored as a grounded (neutral) or grounding conductor, is an ungrounded (hot) conductor.