Electricity: Mounting Boxes


The type of electrical box and mounting hardware you’ll need depends on whether they’ll be set in drywall, wood or plaster. You also need to determine the size of the boxes you’ll need based on the number of wires and devices in each box. Before routing the cable, cut holes for all the boxes. Securely clamp cable to boxes with separate clamps or the clamps that may be incorporated into the box design. Mount wall boxes at the same height from the floor as existing boxes (usually 4 ft. / 122 cm for switches, 12 to 18 in. / 30 to 45 cm for receptacles).

When you’ve decided where you want a box, locate studs or joists that might obstruct it. To check for pipes and other obstacles, drill a test hole into the wall. Bend a short length of stiff wire to a 90-degree angle, insert it into the hole and turn it full circle. If you hit anything, repeat the test nearby until you find a clear area.


Are you looking for home electrical items -- such as switches and fuse boxes -- or parts and accessories for ones you already have? Try our dedicated electrical supply pages here:






Brand Name Manufacturers
Mounting Boxes in Existing Wall Surfaces

Mounting Boxes in Existing Wall Surfaces

1. Select the proper size and type of remodeling box and make sure the desired location is free of obstructions. Trace a box outline on the wall, omitting adjustable ears. Score the drywall along the outline with a utility knife. Cut inside the score line with a drywall saw.

2. Fasten the cable to the box with a cable clamp. Adjust ears so the box front is flush with the wall. Hold the box in the wall and slip brackets between the box sides and wall. With a long-nose pliers, pull each bracket tab forward, folding tightly against the box side to pinch it in place.

Recommended Reading

Try Angie's List!

Recommended Products



More | go to top of page

Want to learn more about home electricity? Visit our home electricity library.

If you need home electricity supplies, browse through the products on these pages:


Mounting Boxes from an Attic


In the attic, remove flooring, center the box on pilot hole, trace its outline and drill a series of holes. From below, cut opening using a keyhole saw. For a plaster ceiling, tape the outline before cutting.

In the attic, remove flooring, center the box on pilot hole, trace its outline and drill a series of holes. From below, cut opening using a keyhole saw. For a plaster ceiling, tape the outline before cutting.

Fit adjustable bar hanger and box between joists so box is directly over hole, its front edge flush with the ceiling. Screw hanger to joists. Nail cleats to joists.
Fit adjustable bar hanger and box between joists so box is directly over hole, its front edge flush with the ceiling. Screw hanger to joists. Nail cleats to joists.

Mounting Boxes from Below

Locate framing members and check for obstructions. Mount box so it’s centered on opening. Run cable to box. Screw patch to joists with drywall screws and seal edges with joint compound and tape.

Locate framing members and check for obstructions. Mount box so it’s centered on opening. Run cable to box. Screw patch to joists with drywall screws and seal edges with joint compound and tape.

Last modified: Saturday, 2007-11-03 1:14 PST