Which wire size is most commonly used for branch lighting circuits in homes?

The most commonly used wire size for branch lighting circuits in homes is #12 A.W.G. This wire gauge strikes a good balance between conductivity and safety for residential lighting applications. It is capable of handling typical current loads for lighting circuits, which usually range from 15 to 20 amps, making it suitable for most home lighting needs.

Using #12 wire ensures that the circuit can effectively power multiple light fixtures and is resilient against overheating under normal use. Additionally, it meets the National Electrical Code (NEC) requirements for the appropriate ampacity, which helps prevent fire hazards and ensures reliable performance.

Other wire sizes may not provide the necessary capacity for standard lighting circuits. For instance, #14 A.W.G. is often used for lighter loads and could be more appropriate for lesser lighting requirements, but it is not as commonly used for general branch circuits since it may not safely support heavier loads. Larger sizes like #10 A.W.G. are typically used for specific applications that require higher current ratings, like certain larger appliances, and #16 A.W.G. is more suited for low-level electronic devices and not standard lighting. Thus, #12 A.W.G. is the choice that aligns best with both safety standards and practical application in residential wiring.