When the hole for a junction box is too large, use a metal cover plate designed to cover excess space. These plates have screw holes aligning with the box's mounting points. This mismatch leaves an exposed gap of drywall, plaster, or paint damage surrounding the electrical junction box. The resulting visibility of the raw cutout and wiring is not only unsightly but also compromises the finished look of the installation. It's a common issue, and it's frustrating because you might feel like you've chosen the perfect new. The main issue I'm running into is that the previous holes for the boxes are ever so slightly too large. It holds about 21 cubic inches. These boxes must be grounded and have safety. The National Electrical Code (NEC), published as NFPA 70, sets minimum safety standards for electrical junction boxes in residential and commercial buildings. Every state has adopted some version of the NEC, though the specific edition in force and any local amendments depend on your jurisdiction's.
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