How to Run Electrical Wire Through Finished Walls?

Hi. I can help you by sharing how to run electrical wire through finished walls. My brother is a certified electrical expert and has been doing this for a long time. Although I am sharing the steps, he told me, please don’t do it on your own, though, as it is the work of a professional. The method is quite extensive, but I will try to simplify it. You can find the steps down.

How to Run Cable Wire Through Finished Walls?

Below, you can find the complete steps to run an electrical wire through walls:

• Cut the openings for the electrical boxes in the drywall once the cable routes and box locations are planned.

• Mark the desired location for the box on the walls. When you insulate them in the finished walls, locate the electrical boxes between the studs. Find the location of the wall studs using a stud finder. 

• After locating the studs, outline the position of the old work electrical boxes on the wall. Ensure the position of the new wall boxes is consistent in terms of the location of the other outlets in your home.

• Use a drywall saw to cut out the box openings along the outline. Ensure not to cut into the current electrical wires, plumbing pipes or other mechanicals. The cutout must exactly fit the outline of the electrical box. 

• After you cut the box holes in the wall, you’ll need to drill access holes in the wall plate at the bottom or top of the stud cavity.

• The holes will allow the cable to go through the crawl space area from box to box.

• After this, insert a spade bit into a flexible bit extension mounted in a drill. Insert the drill bit through the wall opening and center the extension in the stud cavity so the bit is pressed firmly against the wall plate. 

• Use firm pressure as you drill through the plate into the crawlspace. Drill at a slow speed and keep the gas lines, plumbing pipes, etc in mind. Stop right at the point when you feel the drill bit penetrate the wall plate.

• Begin inserting a long wire through the hole you just dripped. Go to the crawlspace and find the wire extending through the drilled hole.

• Remove the wire, uncoil the end of an electrician’s fish tape and insert it through the drilled hole in the wall plate once you find the hole in the wall plate. Extend the blade of the fish tape until it is visible in the wall box opening. 

• Hook the fish tape and extract it through the wall opening. Uncoil enough NM cable to finish the cable run you are planning. Allow about 2 feet of excess table at each end. Stretch out the cable and untwist any kinks in it.

• Strip around 6 inches of outer sheathing from one end of the cable and then hook the conducting wires and bare copper grounding wire through the loop at the end of the fish tape blade.

• Bend the wires over and wrap several loops of electrical tape around the wires and the end of the tape.

• From the basement, pull steadily on the fish tape while someone else pushes the cable into the wall opening. Be gentle when you fish the cable through the hole since it matters that you don’t tear the sheathing on the cable.

This is how to run electrical wire through finished walls.