Running wire with a fish tape
Running wire from a switch location to a light or fan in the center of the ceiling can be a challenging project. You'll almost always have to cut some holes in the walls, but you can minimize ceiling damage by using a “fish tape.” A fish tape is a long strip of spring steel used for pulling wires through walls and ceilings. They're available at hardware stores and home centers.
To map out the best path for the cable run from the switch to the light, first determine the ceiling joist direction. Generally, it's best to run the cable in the space between the joists so you won't have to cut a lot of holes in the ceiling. Then figure how to get the cable through the wall to that joist space.
Since you can't run the cable through the attic, the next best choice is to go down into a basement or crawl space, then go back up through the stud cavity directly below the joist space. If you can't go down, follow the procedure we show here, which is to go horizontally across the studs until you're below the joist space. As you can see in Photo 2, you'll have to notch each stud and the top plate.
Once you know the path of the cable, cut a hole in the ceiling for the chandelier outlet. At each location where the cable will cross a framing member, cut away the drywall. Where the cable will turn from the wall to enter the ceiling, cut out a 3-in.-wide section of drywall in the wall and ceiling (Photo 1). Extend the openings at least 2 in. from the edge of the top plate.
With a sharp 5/8-in. or 3/4-in. chisel, trim the stud or plate back about 1/8 in. so that the guard plate will sit flush with the face of the framing (Photo 4). Then chisel the notches for the cable (Photo 2).
Feed the fish tape from the opening at the top plate to the lighting outlet, connect the cable and pull it through (Photo 3). Then feed the fish tape from your wall switch to the top plate opening, connect the cable and pull it through the wall.
Be sure to install nail guards that completely cover the cable where it crosses the framing (Photo 4). Wire the switch and the lighting outlet, then patch the holes in the wall and repaint.
The Tools You Need
Flex bits, glow rods and fish tapes are the tools electricians use to
fish wires and communication wire. Flex bits are great for drilling holes in hard-to-
reach spaces (see “Invest in a Bumper Ball,” below).
The two most common lengths are 5 ft. and 6 ft., but
extensions are also available. A 3/4-in. x 54-in. flex bit
costs about $50 at home centers. Buy a bit that has a
hole on the end of it so you can use the bit itself to pull
Once your hole is drilled, you can shove a fish tape or glow rod
through the hole, attach your wire to the eyelet at the
end and pull it back through. Glow rods can also be
used to hook wires to pull them out. As their name suggests,
glow rods glow in the dark. This makes them
easier to spot when you’re working in dark areas (which
is most of the time).
Glow rods come in various lengths and thicknesses,
and you can combine as many sections as the job
requires. Thinner rods flex more and work better when
you have to make sharp turns. A thicker rod can span
longer distances and is better for hooking wires that
are more than a few feet away. A 9-ft. glow rod kit costs about $40 to $50 at home centers. You can also buy a 24-ft. kit.
Push through more than you need
Hook on to a flex bit
Seal the Holes
If you’re drilling holes through top and bottom plates or running
wires through a fire wall in the garage, you must seal those
holes with a fire-resistant caulk or foam sealant to comply with
fire and energy codes. Most building officials won’t make you
bust out large holes in ceilings and walls in order to access
hard-to-reach holes, but check with your local official before
you begin your project. A can of fire-blocking insulated foam
sealant costs about $10 at home centers and hardware stores.
Fish wires through the holes for recessed lights
Protect drywall with a mud ring
Install conduit inside cabinets
Hold on tight
Don’t Spin Apart the Glow Rods
Sometimes you need
to twist and spin glow
rods in order to snake
them past ductwork,
pipes and other
obstructions. A great
way to lose a rod or
attachment in a wall
or joist space is to
twist it so many times
in the same direction
that it unthreads and
comes apart. Some
pros wrap a little electrical
tape around the
connections to keep
Get a better view with an inspection mirror
Don’t spin the bit in insulation
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Keep low-voltage wires away from electrical cables
Buy Extra Wire
Have plenty of extra wire or cable on hand, because i’s not likely that
you’ll be able to fish a wire in a straight line from Point A to Point B.
There’s also the possibility that your wire might get hung up on something,
and you'd have to abandon it and start over.