Are flush-mounted boxes required to be mounted flush with the wall?

Flush-mounted boxes are required to be installed so that their front edge is flush with the finished surface of the wall. This requirement ensures not only a neat appearance but also safety and functionality in terms of the electrical fittings that will be placed within the box. When boxes are mounted flush, they allow for proper cover installation and prevent the risk of accidental contact with the edges of the box, which could pose electrical safety hazards.

This requirement is reaffirmed in the NEC, which emphasizes that flush-mounted boxes should be installed properly to align with standard practices for electrical installations. Ensuring that the boxes are flush minimizes risks and maintains structural integrity for attached components, such as switches and receptacles.

The alternative options do not align with the NEC guidelines, as they suggest either an allowance for uneven mounting or limited applications, which can compromise both safety and compliance with the code.