Through-Wall Location Tip for Vent Caps, Light Boxes and Outlets

November 12, 2018


Piano wire drill bit can help you cut holes in the wall right where you want them


When installing exhaust fan hoods, choose where to put the hole carefully. Use a drill and a piece of wire to create a reference point for determining the best location for the hole.


Step by step:

  • File a sharp point on a stiff piece of wire. The wire is the critical element. Matt uses piano wire (12 gauge, .78 in diameter), which can be purchased at a music store.
  • Make a reference mark somewhere on the inside.
  • Drill through the wall, release the wire from the drill and leave it in place.
  • Use that point as a reference for locating the hole both elevation and side to side in reference to framing.


—Matt Jackson is a master carpenter, remodeler, SketchUp Wiz, YouTuber, and contributing editor to ProTradeCraft. He lives and works in Rapid City, South Dakota.