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Electrical rough-in tips for new construction
Rough-in is where a job is won or lost. Watch Percy's five tips, then use this checklist so you pass the rough inspection the first time.
The breakdown, in plain English
- Protect the cable. Where a cable runs through a stud closer than 1¼ inches to the edge, put a steel nail plate on it.
- Staple NM cable within 12 inches of each box and at least every 4½ feet along the run.
- Leave enough wire in the box: at least 6 inches of free conductor, with at least 3 inches sticking out past the box face.
- Count your box fill before you pull wire, especially on boxes with switches and multiple cables.
- Lay out your dedicated circuits (kitchen, laundry, bath, garage) before you start drilling.
- Label your home runs at the panel. Future you will thank you.
Codes to look up
Cables in bored holes or notches close to the edge of framing need protection, like a steel plate.
NM cable is secured within 12 inches of boxes and at intervals no more than 4½ feet.
Leave at least 6 inches of free conductor at each box, and at least 3 inches past the opening.
Box fill: the box has to be big enough for the conductors and devices inside it.
These are plain-English summaries, not the code's exact wording. Always check the full section in the NEC edition your area has adopted, plus local amendments.
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