Install an exterior outlet box in stucco when you want the opening of the electrical box flush with the stucco wall. The installation will entail first tracing out with a marker the location where you want to put the electrical box; followed by putting masking tape around the outside of the trace markings and drilling holes into the stucco a 1/4 inch apart along the inside portion of the outline. By carefully breaking the stucco out and cutting out an opening in the plywood, you will have finished making the access needed to install your exterior outlet box.
Things You'll Need
3/8-inch carbide drill bit
Check the back. Before marking out where you want the exterior outlet box located, check the inside of the wall to see if there are any lines or studs that need to be avoided. You can do this by cutting out an opening in the interior wall around the area you want the outlet box located and taking a look inside. If everything looks good, proceed to Step 2. If not, you will need to relocate the opening of the electrical box to another area.
Mark out where you want the exterior outlet box located. Using a pencil, trace the opening of the outlet box onto the stucco wall. To keep the stucco wall from chipping or cracking, use masking tape to tape around the marked electrical box opening. You should attempt to cut the opening so that the electrical box sits against a wall stud. This will keep the electrical box securely in place.
Drill holes around the inside portion of the tape and chisel out the stucco pieces until you have a clean opening. The plywood sheet that is just underneath the stucco should be fairly easy to chisel out as well. You can use a small sheetrock saw if you need to cut more plywood out. For added safety, be sure to wear safety glasses and gloves.
Insert the exterior outlet box into the opening. After you have cut out the opening, remove the tape from the outline and insert the exterior outlet box. Anchor the outlet box, using the nails or screws provided, to a stud.