How to Build Cabinet Spacing Shelves

Measure the area where the shelf will be installed by taking down the depth of the cabinet and the width of the cabinet at that location. Transfer these dimensions to a 3/4-inch plywood board and draw the outline of the shelf on the board.

Cut out the outline of the shelf from the plywood board using a saw. Sand the edges of the board with medium-grit sandpaper to remove any rough spots or potential splintering areas. Sand all of the surfaces of the board to prepare it for finishing.

Apply a coat of paint or stain using light, even strokes. Make the brushstrokes in the same direction as the wood grain. Allow the first coat to dry for two hours and apply a second coat. Continue to apply paint or stain using this process until the dried surface color and tone reaches that of the rest of the cabinetry. Let the shelf dry overnight.

Position the shelf within the cabinet at the position where you wish to install it. Set a carpenter's level on top of the shelf and adjust the shelf's position until the level shows that it is straight.

Place 1-inch metal L-brackets underneath the shelf board, spacing them every 12 inches against both the shelf board and the rear and side boards of the cabinet. Mark each bracket attachment screw hole against the shelf board, rear board and side boards. Remove the brackets. Drill into all of the marked positions, being careful not to pass all the way through any of the boards.

Reposition the L-brackets lined up with the predrilled holes. Set 3/4-inch wood screws in each hole and tighten them completely using a drill. Repeat as necessary to add additional shelves to the cabinet.