Locate Top and Bottom Plates for Wiring
Use this trick to find into which stud bay you need to drill a hole to run a wire for a new switch or outlet.
I’ve been using this trick for locating exactly into which stud bay I need to drill a hole for running a wire for a new switch or outlet. To get started, locate where in the wall you want to run your wire, and use a 1/8-in.-diameter by 12-in. drill bit to drill a hole so that the business end of the long bit lands in the middle of the top or bottom plate. A stud finder can help you locate the hole between joists (at least at the ceiling if the framing isn’t stacked).
You can usually see where the bit lands in the attic or basement, but if you want to make things even easier, remove the bit and shove in a longer wire painted with fluorescent paint through the hole. Once you locate the wire, drill your final 3/4-in. hole at 90° through the plate and run your final wire. A dab of putty or caulk is often enough to hide your locator hole.
—Marcus Zehnder, Overland Park, Kan.
Edited and Illustrated by Charles Miller
Published in Fine Homebuilding #310