Frame and frameless base units are installed in the same way as wall cabinets, except that with the frameless style there is no margin of error. Start with a corner unit, unless a cabinet in the middle of a run must be perfectly aligned with some other feature, such as a window or the sink plumbing. Set the cabinet in place and shim under the base until the top is even with the layout line. Countersink and drill through the top rail at each stud and attach the rail to the stud with 3-inch screws. If the wall is not straight, place shims behind the cabinet, using a level to check the top, sides, and front. Hold the level against the frame and not against a door or drawer.
Set the second unit in place and attach it to the first unit. Screw it to the back wall.
Complete the run of base cabinets. Some of them, such as lazy susan corner units and sink fronts, have no box to attach to the wall. They are held in place only at the face frames. With frameless styles, the sink fronts have sides that extend back just far enough to attach them to the adjacent cabinets. Because these units have no backs, you will have to provide support for the countertop along the backside. Screw cleats of 1-by lumber to the wall just below the layout line.
You will also need to fabricate a floor for some sink fronts. Cut it out of a piece of Ã‚Â½-inch to Ã‚Â¾-inch plywood and support it on cleat screwed to the wall and to the adjacent cabinets. Seal it or paint it before you install it.
If there will be an appliance in the middle of a run – a dishwasher, trash compactor, or slide-in range – you must allow for it when you install the base cabinets. Check the appliance specifications to determine the exact width of the space. To keep the cabinets on both sides aligned, bridge the gap with a long straightedge at the front and back. Install filler pieces at the end of the run and at the corners.