Short answer: Rough-in is everything before the walls close: layout, boxes, holes, cable pulls and making up boxes, then a rough-in inspection. Trim comes after drywall and paint: devices, plates, fixtures, panel terminations, labeling and testing, then the final inspection. Do not allow electrical work that requires a rough-in inspection to be concealed until the inspection has passed or the local inspection authority has authorized the next step.
Exploring the electrical trade before applying? This rough-in and trim guide shows the type of work apprentices encounter under qualified supervision. If you’re still preparing for entry assessments and interviews, the Texas Electrical Apprenticeship Entry Kit provides separate math, reading, and interview practice. It does not teach installation procedures or replace supervised field training. The kit has 1,300 math practice questions with worked answers, 20 interview questions, and a 7-day start plan. Launch price US$49 through November 30, 2026.
Tsai Electro is an independent learning site. Not affiliated with TDLR or PSI. This page describes a common residential sequence. Your contractor’s methods, the plans and the local inspector come first. Check each code reference in your own 2026 NEC.
Who you work under and who inspects
In Texas, an apprentice electrician works under the general supervision of a Master Electrician, Journeyman Electrician or Residential Wireman (TDLR apprentice page). Texas adopted the 2026 NEC as the state electrical code effective September 1, 2026 (TDLR rule adoption notice). Which inspections a job needs, and when, is set by the local inspection office. Ask your supervisor which inspections this house needs before you start.
The sequence from slab to keys
| Stage | What happens | Hold point |
|---|---|---|
| 1. Temporary power and underground | Temporary pole, any conduit in or under the slab | Underground inspection before backfill or pour, where required |
| 2. Layout | Mark every box location and height from the plans | Supervisor walk-through of the layout |
| 3. Set boxes | Nail-on or bracket boxes at the marked heights, flush with the finished wall | |
| 4. Drill and pull | Bore framing, pull cable, staple and protect | |
| 5. Make up | Splice grounds, fold conductors, label home runs | |
| 6. Rough-in inspection | Inspector checks boxes, cable, support and protection | Do not conceal work requiring inspection until it passes or the local inspection authority authorizes covering it. |
| 7. Insulation, drywall, paint | Other trades close the walls | |
| 8. Trim | Devices, plates, fixtures, panel terminations | |
| 9. Test and label | Polarity, GFCI and AFCI tests, panel directory | |
| 10. Final inspection | Inspector checks the finished work | Local inspection and utility rules decide when power is released |
Rough-in checklist, room by room
- Box locations and heights match the plans and the specs, including counters, vanities and appliances.
- Set boxes and listed extensions for the actual finished wall material. Check the permitted box setback for noncombustible surfaces and the finished-surface requirement for combustible surfaces. Verify the applicable installation rule before closing the wall.
- Holes bored back from the face of the stud so cable is protected; where it is too close, a steel plate goes on (300.6(A)(1)).
- Cables stapled within the required distance of each box and at the required spacing along the run (334.30).
- Enough free conductor at every box for devices and splices (Article 300).
- Box fill checked for boxes with several cables or devices (see NEC 314 box fill).
- Grounds spliced and folded in the back; conductors that will be on the same device grouped together.
- Home runs labeled with the circuit number at the panel end.
- GFCI and AFCI circuits marked so trim does not miss them.
Trim checklist
- Walls are painted and dry before devices go in, unless your contractor says otherwise.
- Devices match the plans: type, color, rating, and tamper-resistant receptacles where dwellings require them (406.26).
- Terminal screws tightened to the torque the manufacturer lists (110.14(D)).
- Push-in terminals used only as the device listing allows.
- Plates straight and flush, no gaps around the box.
- Fixtures supported as their instructions require.
- Panel terminations are completed by authorized personnel under the employer’s electrical safety procedures, including required isolation and verification before work. Breakers, neutrals, grounding conductors and circuit identification match the approved design and equipment instructions (408.4(A)).
- Receptacle polarity and grounding are verified, and GFCI and AFCI protective functions are tested, by a qualified person following the employer’s electrical safety procedures and the manufacturer’s instructions. Apprentices must not treat these tests as permission to work on energized wiring.
Worked example 1: receptacles on a wall
For general wall space in a dwelling room, no point along the floor line may be more than 6 feet from a receptacle (210.52(A)(1)). That means one receptacle covers up to 6 feet on each side, 12 feet in total.
For this exercise, assume a 16-foot continuous bedroom wall space with no doors, fireplaces or fixed cabinets.
- One receptacle covers at most 12 feet of wall. 16 is more than 12, so one is not enough.
- Two receptacles: one at 6 feet from the left corner covers 0 to 12 feet. One at 12 feet covers 6 to 18 feet. Together they cover all 16 feet.
- Answer: at least 2 receptacles on this wall. The plans may show more.
Check: 16 ÷ 12 = 1.33. Round up to 2.
Worked example 2: a cable takeoff for one bedroom
Before rough-in, your lead asks you to estimate the cable needed for one bedroom. For this exercise, assume the approved plans specify 14/2 NM cable for the listed runs and that your supervisor has already checked the circuit design. You measure the routes on the plan:
- Home run from the panel: 38 feet
- Six receptacle-to-receptacle runs, about 12 feet each
- Two switch-leg runs: 9 feet and 8 feet
- Receptacle runs: 6 × 12 = 72 feet.
- Total measured: 38 + 72 + 9 + 8 = 127 feet.
- For this exercise, add a hypothetical 10% allowance for routing and extra length at boxes: 127 × 1.10 = 139.7 feet. This percentage is an estimating assumption, not an NEC requirement.
- Round the exercise estimate up to 140 feet. Before pulling cable on a real job, confirm the route, required free conductor lengths, circuit specifications and material allowance with your lead.
Check: add in another order. 8 + 9 = 17, plus 72 = 89, plus 38 = 127. 127 + 12.7 = 139.7.
Mistakes that cost a rough-in inspection
- Boxes set for 1/2-inch drywall in a room getting thicker wall material.
- Cable run too close to the face of the stud with no plate.
- A missing box where the plans show a smoke alarm or a range receptacle.
- Insulation installed before the inspector saw the work.
- Grounds left unspliced or cut too short to work with.
Check yourself
Our own practice questions. Answers below each.
- A 26-foot wall with no openings. Minimum receptacles from the 6-foot rule? Answer: 26 ÷ 12 = 2.17, round up to 3, so no point along the floor line is more than 6 feet from a receptacle.
- Measured runs total 210 feet. With 10% extra, how much cable? Answer: 210 × 1.10 = 231 feet.
- Insulation crew shows up before the rough-in inspection. What do you do? Answer: Tell your supervisor right away. Do not allow the work requiring inspection to be concealed until it passes or the local inspection authority authorizes covering it.
Disclosure: If you buy through the Amazon link below, Tsai Electro may earn a commission at no extra cost to you. As an Amazon Associate I earn from qualifying purchases.
A wire stripper for common rough-in and trim tasks
Klein Tools 11055EP wire cutter and stripper. Strips and cuts 10 to 18 AWG solid and 12 to 20 AWG stranded copper, loops wire with the holes in the handle, shears 6-32 and 8-32 screws, and is made in the USA, per the listing. This is not an insulated tool and its handles do not protect against electric shock. Use it only as permitted by your employer’s electrical safety procedures. Ask your contractor which hand tools you are expected to bring before you buy.
FAQ
What is rough-in electrical work?
The part of the job done before the walls are closed: setting boxes, drilling framing, pulling and securing cable, and making up the boxes. It ends with a rough-in inspection.
What is electrical trim-out?
The finish stage after drywall and paint: installing receptacles, switches, plates and fixtures, terminating the panel, labeling circuits and testing, followed by the final inspection.
Can insulation go in before the electrical rough-in inspection?
No. Do not conceal work that requires a rough-in inspection until the inspection has passed or the local inspection authority has authorized covering it. Confirm the required inspection sequence with your supervisor. Covering it early can mean opening walls for the inspector.
How far apart do receptacles have to be in a house?
For general wall space, no point along the floor line may be more than 6 feet from a receptacle, so receptacles are placed no more than 12 feet apart and within 6 feet of each end of the wall space.
Sources checked October 2026
- TDLR apprentice page (general supervision): https://www.tdlr.texas.gov/electricians/apply/individuals/apprentice-electrician.htm
- TDLR rule adoption notice, 2026 NEC: https://www.tdlr.texas.gov/news/rulemaking/2026/09/01/commission-adopts-rules-12/
- NFPA 70 (NEC), 2026 edition, Articles 210, 300, 314, 334 and 406, read in your own copy: https://www.nfpa.org/codes-and-standards/nfpa-70-standard-development/70
