If you've ever had to add a new wire, for an outlet or switch, in an existing wall, this tip will surely help. One option is to take down the drywall, which is not only time consuming, but also is costly and is messy. And for running it on the surface, yes it is possible with Wiremold products, but to me, it just looks unprofessional and tacky. Feeding the wire from a basement, crawlspace, or attic is a much neater solution, but how in the world do you get the wire into the wall cavity?
1. Fish A Wire From the Basement Or Crawlspace
Photo: Timothy Thiele
Drilling a bunch of studs in a wall that is covered by drywall seems impossible at the least. So why go to all of that trouble? Doesn't it just make good sense to runn thw wiring under the floor joists where access is easy and there is hardly anything in the way? But ho do you get the wiring from the basement or crawlspace area up through the wall on the floor above? That indeed is the burning question.
2. Locate And Cut A Box Opening
In order to gain access to a wall cavity in order to fish an electrical wire into it, you must first choose the location you want to install the outlet. Once located, mark the box opening on the wall between two studs. You may find it easy to do this with a stud finder. We will be using a cut-in box to add this device. On drywall walls, use a drywall saw, reciprocating saw, or jigsaw to cut the opening. Be aware that there may be electrical lines, plumbing, heat ducts or other obstacles behind the wall.
3. Drilling The Floor Plate To Fish An Electrical WireOnce the hole is cut in the wall, install a long flexible drill bit into an electric or battery operated drill. Insert the drill bit into the opening and center the bit tip as well as you can within the wall cavity. Gently press down while drilling the hole throught he wall stud and the plywood floor. With any luck, you should go right through the floor and into the basement or crawlspace opening. Keep in mind that there may also be things below like gas lines, plumbing runs including water lines, electrical wires, etc... that are hidden dangers. My suggestion is to drill slowly and not press very hard. Stop when you feel the drill penetrate the floor.
4. Marking The Floor Opening To Fish The Electrical WireNow that the wall plate has been drilled and you are ready to install the electrical wiring, you'll need to go into the basement or crawlspace and find the hole. If you've ever had the thrill of crawling on your hands and knees in a spider web infested, filthy crawlspace, you already know that finding a small hole is certainly a challenge in a large area. Why even looking for it in a basement can be a challenge. So what's the secret to finding this tiny drilled hole? Well, I install a wire or fish tape through the hole in the floor and let it dangle through the hole. This serves two purposes; one is to make it easy to find, and the other is to fish the electrical wire through the hole into the wall opening.
5. Fishing The Electrical WireFishing the electrical wire is easy when you attach it to a fish tape or a pull wire. Fish tapes are nice because they have a loop on the end and are strong steel pieces of metal that can pull a load. When pulling nonmetallic sheathed cable, simply strip back a few inches of the outer sheath and expose the inner wires. To make this simple, cut off the two insulated wires (black and white) and leave the bare ground wire. Wrap the bare wire through the fish tape eye and twist the end of the wire around itself. Place electrical tape over the end of the fish tape eye and wire. You are now ready to pull the wire through the hole. In the instance of a pull wire, you'll have to make your own eye on the end in order to attach the wire to be pulled.
6. Pulling Cable With A Fish TapeWith one person standing at the box to feed the wire, pull evenly on all of the wires to be fed. Try to keep the wire untangled as you feed it. As for the person actually doing the pulling on the other end, pull the wires in two to three foot intervals. Count to four and then pull again. Pulling too fast can nick the wires and catch your helper's fingers. Leave enough time between pulls so that the person feeding has time to lubricate the wire or pull enough off to feed into the hole. A simple signal to alert each other that you are ready for the next pull is to tap on a pipe or the floor with something like a tool.
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