enter image description hereThis may be a stupid question, but is there any way to add a light fixture at the top of the staircase without directly wiring it to the existing light fixture at the bottom of the staircase? There are 3 way switches at the top & bottom of the staircase, with the circuit's power coming in at the junction box for the switch at the bottom of the stairs. I don't want to destroy the ceiling/walls trying to figure out where the existing wiring is routed since the switches are on opposite walls in the staircase.

I attached a rudimentary diagram.

  • Hello, and welcome to Home Improvement. Interesting question: keep 'em coming. And, you should probably take our tour so you'll know how best to participate here. Sep 19 '19 at 18:56

With the existing light on, you might have luck with a voltage detector (my stud finder does this) to locate within the wall where the wires run.

You may be able to attach the new fixture into the 3-way switch at the top of the stairs, but you will probably have to open the wall somewhere to run wires.

  • 1
    no Neutral at the upper switch would be a problem here.
    – Ed Beal
    Sep 20 '19 at 14:48
  • @EdBeal, yes, you are absolutely right.
    – spuck
    Sep 20 '19 at 15:32

The obvious way isn't possible because you don't have a neutral at the top of the stairs.

There is a way, but it involves a bit of lateral thought and a change in how you switch the lights.

You rewire so that your black/white/red cable becomes live/switched live/neutral.

You then have two single-way switches in parallel across live and switched live. You can wire a light from switched live and neutral at the switch at the top of the stairs.

Now both lights will work when either switch is on. Problem - you won't be able to turn the light off from downstairs when you've turned it on upstairs. You need a switch which will reset itself automatically when the light is not needed:

  1. time-lag switches as used in blocks of flats (UK pneumatic type shown, electronic equivalents are available) which will operate for a set period.


  1. passive infra-red detectors


which will operate whever motion is detected.

The two time-lag switches are wired in parallel with live/switched live/neutral at both switches, and the lights between switched live and neutral.

An added advantage of PIR detectors is it leaves your hands free if you are carrying things down stairs.

  • 1
    There are code requirements for light switches in stairways. There must be a three way switch at the top and bottom and I'm not sure if any of your alternatives would meet the technical requirements. It would need some more research.
    – JPhi1618
    Sep 19 '19 at 20:35
  • 1
    This is close but smart switches would be the way to go they are a bit more pricy but work from 2 locations (or more). Lutron makes several models that would do it but the wiring will need to be changed a bit. Caseta wireless smart switch will do it. And I believe the maestro master / slave will also work here .
    – Ed Beal
    Sep 20 '19 at 14:56
  • I know this is a year old, but your first statement is flat wrong. According to the OPs diagram, the cable running to the top of the stairs contains "Black, WHITE, Red, Ground", thus there is (or at least should be) a neutral at the top of the stairs. You acknowledge this in your 4 paragraph, "You can wire a light from switched live and neutral at the switch at the top of the stairs"
    – FreeMan
    Oct 14 '20 at 11:34

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.