Summarize the following:
If you plan to add new wires or a light switches that to an existing kitchen outlet, make sure the electrical box that houses the outlet has enough room. You will have to replace the box with a larger one if it doesn't. Use the National Electrical Code to determine the size of the electrical box. Calculate the amount of wires, devices, and clamps you will put in the box. Add 1 cubic inch for each hot and neutral wire, 2 cubic inches for each device (such as a switch), 1 cubic inch for all ground wires, and 1 cubic inch for all clamps. Take this sum and multiply it by either 2 for 14-gauge wire or 2.25 for 12-gauge wire. This calculation will give you the minimum box requirement in cubic inches. You do not have to do calculations for plastic boxes as the volume is stamped inside of them. Do this at the circuit breaker. Find the switch labeled kitchen and make sure it's off. Test to see if the power is turned off, plug in a device such as a lamp or radio into the outlet and see if it turns on. You can also use a receptacle tester on the outlet. The lights on the test will come on if any power still running into the outlet. While the circuit breaker may be labeled, make sure you test the outlet anyway. There may have been changes in the wiring since the box was installed, or the wiring may be defective. First, unscrew the wall plate that holds the outlet. Then, unscrew the outlet from the electrical box. Take the outlet out and disconnect any wires that are connected to it. The electrical box is nailed to a wall stud. Look around the electrical box to determine which side the stud is on. Use a flashlight if it's too dark to see. You don't want to saw through the stud when you are expanding the hole to hold new electrical box. Hold the new electrical box over the existing box in the wall so the expansion of the hole is on the side that isn't nailed to a stud. Use a pencil to make an outline of where you will cut with the drywall saw. Make sure that any wiring connected to the old electrical box is loose before removing it. Pulling out the box when the wires are tight will damage the wiring. Once you are sure that wires are loose, remove the old box by using a flat pry bar.
Determine if you need a new electrical box. Turn off the power to the kitchen. Remove the outlet from the electrical box. Draw an outline of the new electrical box. Remove the old electrical box.