Installing a dual switch from a single switch which powers two wall sconces

Question

My living room has one wall switch that feeds two different lights/ sconces . The switch has only two black wires on the side of the switch. one on the top and one to the bottom .

I would like to install a dual switch where one of the black wires, instead of feeding a wall sconce, feeds a ceiling fan, and use the other black wire to continue to feed the other wall sconce . The sconce that I want to rewire to feed the ceiling fan has only a white wire and a black wire powering that light. However, there is no white wire coming off the switch, there are only two black wires.

Must I make adjustments to other wires that are in the box behind the switch ?

It looks like a mess in that box behind the switch , with white wires joined and two black wires joined to white and black wires .

Pictures upon request . Thank you in advance .

Answer 1

I think you misunderstand the design of the switch in the circuit.

A single pole switch in a circuit just makes or breaks a single wire. When it is off, one of the wires is a hot feed from the main panel and the other goes to the light. When you turn it on, it connects the two together and acts as if the wire was one continuous wire. That is why there is no white wire on the switch. Switching the white wire (neutral) is prohibited.

If you want to control the ceiling fan with a separate switch you will at least need one more wire from the switch location to sconce and on to the ceiling fan, along with the white from the switch location or sconce. (Or a wireless electronic switch could be used with a receiver at the fan location.)

Either way you need more than what you have available.