Home>Discussions>ELECTRICAL & LIGHTING>Changing single pole switch to 3-way
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Albert
Changing single pole switch to 3-way

I am finishing a basement. Currently, the light on the landing and in the basement is controlled by a single pole switch at the top of the stairs. A 14-2 wire comes from the box to the basement light where a 14-3 continues to the switch. From there to the landing light is another 14-3. Current continues there to the rest of the circuit. How can I change this to a 3-way with a switch at the base of the stairs with a minimum of rewiring?

Sombreuil_mongrel
Re: Changing single pole switch to 3-way

Hi,
You need to buy some "3-wire" and two three-way switches. Install the wire between the two switches using the handy wiring diagram on the box.
S_M

JLMCDANIEL
Re: Changing single pole switch to 3-way

You will need to run a new 14-3 from the switch box to the new switch box. Connect the always hot on the old switch to the "C"terminal on the replacement 3 way, connect the white and red wires of the new 14-3 to the "T" terminals on the replacement 3 way, wire nut the switched wire from the old switch to the black wire of the new 14-3. In the new switch box connect the red and white wires to the "T" terminals on the new 3 way, and the black wire on the "C" terminal of the new 3-way.

Jack

Albert
Re: Changing single pole switch to 3-way

Thanks for your help. In your scenario, could I connect the existing 14-3 that runs from the downstairs light to the existing switch to the new switch if I moved the 14-2 coming from the breaker box to there as well? Or would this put the entire circuit on the switches? Also, if I did that, how would I wire the basement light controlled by the switch? The only reason I ask is that the existing switch is in a difficult position to run new wire without tearing out existing drywall or ductwork.

JLMCDANIEL
Re: Changing single pole switch to 3-way

Unfortunately no. The circuit you described is using the leads of the 14-3 to feed
power and common as a feed trough in the circuit and the 3rd. wire as a switch leg.
It will probably require some blocks cut out of the drywall to feed the wire and then drywall patching. Done properly this is not a big or complicated task.
Jack

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