Installing a dishwasher under a granite countertop sounds harder than it is. Since most dishwashers, openings and counter heights are standard sizes, there is no need to remove the countertop for the installation. Be sure you have an opening under the countertop of 24 by 34 ½ inches, access to hot water and a power supply. The dishwasher will slide under the countertop lip for a snug fit.

1
Make sure all power and water supplies are turned off. It is best to disconnect the power from the circuit breaker and reconnect later.

2
Determine if you need to run an electrical lead from where the dishwasher will go to the breaker box. If there is not an available switch on the breaker box, you will need to add to your breaker box or create a lead that will attach to your power source. Make this lead as long as you need, as it won't affect the performance of the dishwasher. It's best to hard-wire appliances, but you can also use extension cords and existing outlets.

3
Drill three holes in the side of the cabinet the dishwasher will abut for the three main connections: drain hose, hot water supply and electrical connection. Drill the holes on the side that is closest to your drain and hot water supply or sink.

4
Set the dishwasher halfway into the open space, leaving room to run the drain hose, electric, and water supply. Most dishwashers come with a drain pipe attached, but make sure it is the correct size and length. If it is not, connect a new drain hose that will reach to your drain source using a connector or hose clamp. The same applies to the hot water supply hose.

5
Set the dishwasher all the way in the opening and, using a level, make sure it sits flat on the floor. Depending on the make and model of the appliance, the door should be flush with the rest of the cabinetry when shut, but not higher than the lip of the counter. Most models have a two-piece panel to allow for adjustments on the bottom, to raise or lower the appliance, and metal connector bars on the top to attach under the countertop.

6
Connect the drain hose (usually to a garbage disposal under the sink) using the adjustable wrench, and connect the hot water supply hose to the shut-off valve of the hot water pipe under the sink. Most of today's plumbing has these connections built in, but you may have to replace the piping to accommodate the connections.

7
Secure all connections, and restore power and water supply.