Electrical Wiring in the Home/adding a switch to old wiring


Mr. S,

I have a switch to a ceiling fan and light and would like to use this switch to power a second switch, in the same switchbox, to control my porchlight which has no switch - you have unscrew the bulb to turn it off - and is currently on a different circuit. When I replaced the light there were 2 wires sticking out of the wall that looked the same and I hooked them up to the two wires from the light and have never had a problem with it other than no switch to control it. I was going to pigtail to the power coming into the 1st switch and run to the light from the second switch but there is no neutral for the return wire from the light to pigtail to in the switchbox. I have had most of the house rewired already and plan to finish up in the near future...but meanwhile where should I tie in the neutral coming from the porch light. Can I tie into the neutral at the ceiling fan controlled by the feeding switch.  Or, if I added a switch to the light as is (which would keep it on the same circuit) is it correct that I run the hot wire from box to the switch and from the second screw on the switch run a black to the black on the light and then tie the white from the light and the power source together?


You should tie the hot and the neutral at the same location.

The best thing to do is to just add the switch to the existing light and circuit.  The black power supply would connect to one screw of the switch, and the black wire going to the light would connect to the other screw.  The whites would connect to each other, and the grounds would connect to each other.
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Electrical Wiring in the Home

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Bob Sponaugle


Just about any home wiring question. (not appliance repair) I have done all kinds of home wiring for myself, including adding a new breaker box, etc. Please, questions from North America only. Please be specific with details.

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