Re: Adding a light fixture to a switched circuit
yes, you can add a light fixture to the outlet. You can maintain a switched outlet or wire it constant hot and have the light be independently switched regardless of the configuration of the outlet.
Currently, your incoming hot is split at the outlet, the common (white ) is attached to the outlet, the hot (black ) is run up to the switch and back down to the outlet. Because they don't make wire cable with two black wires, a standard piece of romex is used, the incoming hot is pigtailed to the black side of the switch leg. At the switch the black turns to white and is run back down to the outlet's hot side terminal, completing the circuit.
What I would do is wire the outlet to be constant hot and run a new wire from the outlet to the light fixture to supply power to the light fixture. To wire this, you would bundle your black incoming with the switch black and a pigtail to attach to the outlet's brass screw. The incoming white would be bundled with the light fixture's white and a pigtail to the outlet's silver screw. The switch white would attach to the light fixture black, thus completing the light fixture circuit. To make this obvious to anyone else who works on this circuit, redesignate the white switch wire at both ends with a black sharpie.
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