How do I wire a 2way 2light system. On the upstairs landing I want to switch 2 lights on and off at each end of the corridor.

  • Does googling "two way light circuit" not give you the information you need?
    – AndyT
    Nov 27 '15 at 10:08
  • For some strange reason, switches that control lights from two locations are called 3-way switches (maybe because they had three hot terminals). When you add more than two switches, each additional one is a 4-way switch (four hot terminals).
    – bib
    Nov 27 '15 at 13:58
  • To install wire so that switches ("3 way") at separate locations can control the same two lights will be dependent on how the existing wiring (if any) are installed. It would be easier to answer your question if you can explain with more detail: 1) if there is already any switches or lights at any of the locations where the new 3-way switches and fixtures will be installed? and 2) if there is a compatible (110 or 220) voltage/power source to tap into? If you are only interested in how the wires are installed for the sake of becoming knowledgeable (and not doing the work yourself) it would be h
    – ojait
    Nov 27 '15 at 15:54
  • @bib I'd say that's a fair assessment. If you have 2 switches, and both of them only have 2 positions, it might seem weird to call them 3-way switches. But if you called the 3-way switches 2-way switches, then what would you call a 4-way switch if there were only 3 switches total in the circuit? Or 5? And, then, if you had 3 switches, would you have to call all the switches 3-way switches because there are three of them? ;-) Anyway, yeah, "3-way" and "4-way" just relates to the number of terminals on the switches. :-) Nov 27 '15 at 19:48
  • What country are you located in? Nov 27 '15 at 23:02

It sounds like you want a pretty straightforward lighting circuit with a 3-way switch at each end of the hallway controlling the lights. To do this, you must have 3 conductors running between the switches. The typical way to do this is to run a 3-conductor cable, such as 14/3 NM or MC cable. You can't legally string a lone wire through the attic, so pull new cable if you need it.

This answer might be helpful, and it references others.


You need two wires running between two 2-way switches. The common terminal on one switch has the live feed. The common terminal on the other switch is connected to the light bulb. The light will turn on if both switches are up or both are down.


No matter what they call them - they're 2-way switches. They can only be one way or the other.

If additional switches are required then cross-over switches are inserted between the other two. These have four terminals and connect straight through in one position and swap over in the other.

Isolate the circuit completely at the fuseboard before starting work, confirm the circuit is dead and don't switch back on until completed.

  • Insisting they're 2-way switches regardless of what they're called by essentially the entire world and totally regardless of how accurate your statement is, is likely to confuse the OP more than help, no? ;-) If the OP runs down to their local hardware store and asks for a 2-way switch, we both know they aren't going to get what they need. Nov 27 '15 at 20:31
  • You actually need, at a minimum, three wires running between the switches. The third wire is either the neutral for the circuit or a return switched hot if one of the switches is on a switch loop. Under the code, you must have a return flow of current in the cable to avoid induction heating of metal components on the line. Current code also requires a neutral at every switch, so if you have a three way switch on a switch loop, you need 4 wire cable even if the neutral is going to be capped at that switch.
    – bib
    Nov 27 '15 at 20:35
  • The code depends on the country. It isn't a requirement in mine and country wasn't given in the question.
    – Transistor
    Nov 27 '15 at 21:09
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    @Craig, I did a quick web search. Only half the world appears to be confused. ;^) Search for 3-way switch and you'll get North American wiring examples. Search for 2-way and you'll get European. No wonder OP is struggling!
    – Transistor
    Nov 27 '15 at 21:25
  • @transistor That's a fair point. Nov 27 '15 at 23:01

Electrical work can be a hazardous and lethal undertaking. If you have not been shown by an experienced tradesperson how this work is accomplished and what dangers to avoid, Than you might want to enlist the help of someone with experience with electricity. The reason for my answering in this manner is due to the way you are phrasing your question. I can't help but feel it might be better for you to hire someone for this job. If my assumption is completely incorrect and that you are soliciting answers to be able to understand how this installation should progress, please edit your question to add more detail and I will dutifully respond to the best of my abilities.

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