How to Rough-In Electrical Wiring
Do-it-yourself guide with professional techniques for a safe wiring job.
IntroductionYou can save a lot of money by doing your own wiring. Here we'll show you to wire an entire room. Even if you've never picked up an electrical tool in your life, you can safely rough-in wiring by following the directions in this article. You'll learn all of the pro techniques for a wiring job, including choosing the right size receptacle boxes, running cable throughout the room, and making the electrical connections.
- Drill/driver - cordless
- Tape measure
Plastic boxes and flexible nonmetallic cable (commonly called Romex) put electrical wiring projects within the skill range of every dedicated DIYer. In this article, we’ll show you some house wiring basics—how to position outlet and switch boxes and run the electrical cable between them. We won’t cover many other house wiring details. For help with circuit design and making connections to your main electrical panel, we recommend you consult a licensed electrician.
Need help deciding whether to DIY or hire an electrician? Find out how much an electrician costs.
Besides standard hand tools, you’ll need a special-purpose tool to cut and strip electric wire. We like the Klein No. 1412 ($18 at hardware stores and home centers). To drill a few holes, use a 3/4-inch spade bit in your electric drill. For larger jobs, rent a heavy-duty right angle drill ($25 per day) and equip it with a 3/4-inch x 6-inch auger bit ($7).
Electrical house wiring mistakes can be deadly, so make sure you obtain a permit from your local building department and have an electrical rough-in inspection scheduled with a building official when you’re finished. Draw a sketch of your room that shows lighting, switch and outlet locations. Review your plan with the inspector and ask whether there are any special requirements.
Be safe! Here are the top electrical mistakes to avoid:
Project step-by-step (13)
Mark the Box Locations
- Measure and mark the center of each box.
- Mark the height from the floor to the center of the boxes (usually 48 in. for switches and 12 in. for outlets) or line them up with existing boxes to determine electrical outlet height.
- Use letters and symbols to identify boxes.
- Add 2×4 blocks to position boxes away from wide window and door trim.
Mark Box Location with These Symbols
- Mark the box locations on the studs using symbols to indicate outlets, switches and lights.