NEC 90.15: rough-in checklist

What rough-in really means under the code

Rough-in is every wire, box, and support installed before the inspector signs off and the drywall goes up. Get it wrong now and you are cutting rock later. The NEC treats rough-in as the backbone of the finished install, and several articles govern what you pull, where you land it, and how it gets secured.

Think of this checklist as the pre-cover walkthrough. Hit every item before you call for inspection. Missing a staple or shorting a box on fill will send you back with a cutout wheel and a bad mood.

Box fill and conductor count

NEC 314.16 is non-negotiable. Every conductor, device, clamp, and equipment grounding conductor group counts toward total cubic inch fill. A 14 AWG conductor counts as 2.0 cu in, 12 AWG as 2.25 cu in, 10 AWG as 2.5 cu in. Yoke devices count as two conductors of the largest size terminated on them.

Internal cable clamps count once for the largest conductor in the box. All equipment grounding conductors together count as one conductor. Looped, unbroken conductors at least 12 inches long count as two per NEC 314.16(B)(1).

• Standard 18 cu in single-gang plastic box: max 9 x 14 AWG conductors before device, clamps, and grounds
• Deep 4 inch square with plaster ring: read the cubic inch stamp, do not guess
• NEC 300.14 requires at least 6 inches of free conductor measured from where it enters the box, with 3 inches extending past the opening

If the box has a cubic inch marking that you cannot read after you nail it in, write it on the stud next to the box with a Sharpie. The inspector will thank you and so will future you.

Cable support and securing

NEC 334.30 sets the rules for Type NM cable. Secure within 12 inches of every box and at intervals not exceeding 4.5 feet. Staples must not crush the sheath. NEC 300.4(D) requires cables run parallel to framing to be kept back at least 1.25 inches from the edge, or protected with a 1/16 inch steel plate.

Bored holes through studs need to hit the 1.25 inch setback too, per NEC 300.4(A). If you cannot get the bit centered, nail plate it. NEC 300.11 requires independent support: cables cannot ride on suspended ceiling grid, piping, or other cables.

• Verify staple spacing on every long horizontal run before closing walls
• Nail plate every bore within 1.25 inches of the stud face
• Bundle no more than 9 current-carrying conductors through the same fire-stopped hole without applying ampacity adjustment per NEC 310.15(C)(1)

Device spacing and branch circuit layout

Receptacle spacing in dwelling units follows NEC 210.52(A): no point along a wall line more than 6 feet from a receptacle, any wall 2 feet or wider gets one. Countertops follow 210.52(C) with the 24 inch rule and the 12 inch wall-space minimum.

Small appliance branch circuits (210.11(C)(1)), laundry (210.11(C)(2)), and bathroom (210.11(C)(3)) circuits are dedicated 20 amp runs. Pull them separate at rough-in. Do not share neutrals across circuits unless you are running a multiwire branch circuit handled per 210.4.

GFCI, AFCI, and grounding prep

NEC 210.8(A) GFCI protection covers bathrooms, garages, outdoor, crawl spaces, unfinished basements, kitchens, sinks within 6 feet, laundry, and more in the 2023 cycle. NEC 210.12 AFCI protection covers nearly every 120 volt, 15 and 20 amp outlet in dwelling unit living spaces.

At rough-in, flag which boxes need combination AFCI/GFCI breakers or dead-front devices. Label the home run at the panel with the circuit purpose and protection required. NEC 250.148 requires all equipment grounding conductors in a box to be spliced together and bonded to any metal box.

• Bathroom: GFCI and AFCI, 20 amp dedicated circuit
• Kitchen small appliance: GFCI and AFCI, two 20 amp minimum
• Bedroom: AFCI required, GFCI where within 6 feet of a sink
• Garage: GFCI, AFCI not required unless serving a habitable space

Tag every home run at both ends with the circuit number and the protection type. When the trim crew hits the panel two months later, they will not be guessing which breaker feeds the master bath.

Pre-inspection walkthrough

Before you call the inspector, walk the job with the plan in hand. Every box should be plumb, flush to the finished surface per NEC 314.20, and have its cables stapled and stripped to length. Verify nail plates are on every bore that needs one. Check that all EGCs are pre-spliced with pigtails hanging, not just cut to length.

Count your conductors against your box fill calc, especially on three-way and four-way switch loops where the traveler count adds up fast. Confirm panel home runs are labeled, landed on the correct breaker slot if you are pre-landing, and that the grounding electrode conductor is sized per NEC 250.66.

1. Every box flush and plumb, correct depth for finish
2. 6 inches of free conductor, 3 inches past the opening
3. Staples within 12 inches of boxes, 4.5 feet on runs
4. Nail plates on every bore within 1.25 inches of the face
5. EGCs spliced with pigtail, box bonded if metal
6. Home runs labeled, dedicated circuits separated
7. GFCI and AFCI locations marked at panel

Walk it twice. The second pass always finds the missed staple.