How to Install Wall-Mounted Countertops
Measure the countertop length to determine the spacing needed for the braces that hold the counter mounted to the wall. Use a tape measure to take the measurement and then divide the length by 16 inches, as you’ll need a brace for every wall stud running along the length of the counter. Most wall studs measure 16 inches apart, but you’ll want to make certain to have no more than 30 inches between brackets for full support.
Run a stud finder across the wall where you wish to place the countertop. Examine the device for the indicator showing the location of a wall stud and mark its location on the wall with a pencil. Place a carpenter’s level onto a straightedge at the height that you wish to place the countertop and draw a line across the wall studs that the counter will pass through with the pencil, using the level to keep the line level.
Measure the height of the brace and mark a line across the countertop length along the wall below that of the first line placed to mark the countertop height.
Fill the spaces between the two lines with two-by-four planks to create a backerboard support for the countertop braces. Cut the boards to the same length as the countertop using a circular saw. Anchor the boards in place with wood screws driven through the boards, the drywall beneath and into the wall studs with an electric screwdriver.
Paint the backerboard with an interior paint the same color as the walls. Use a paint roller to roll the paint onto the front of the boards and a paintbrush to cover the sides. Allow the paint to dry for two hours before installing the braces.
Place each countertop brace onto the backerboard, centered on a stud with the top of the brace against the top level of the board. Mark the mounting circles in the brace with the pencil, and then remove the brace from the board.
Drill a pilot hole at the marked mounting points through the board and drywall, and into the wall stud beneath. Use a drill bit that will provide a hole for the placement of a 1/4-inch lag bolt.
Hold the braces back against the backerboard, aligned with the mounting holes, and secure them to the wall using the lag bolts. Screw the bolt into place with an electric screwdriver, using a ratchet bit.
Lay the countertop onto the top of the braces. Screw lag bolts through the brace into the base of the counter, making sure that you use bolts that are short enough not to extend through the top of the counter.