Chandelier installed, New Duplex switch--Done!5 --(ignore switch on left for outdoor light)I have four recessed ceiling lights controlled by two three-way switches in my kitchen. I want to add a chandelier and would like to replace one of the three-way switches with a duplex switch(so I don't have to install a larger box) so the chandelier can be turned ON/OFF separately from the existing recessed lights. Can I grab power for the chandelier from the existing three-way switch? How would this be wired? I'm in the USA(NYC).
The key for you will be finding a double switch that has a 3 way and a one way, seeing as you want to eliminate the need for changing out your box - assumption here is that you have an existing installation with drywall already in place. There is another factor at play though - NEC CODE requirements for how many wires you can put into that existing box. - How much space - you can't just stuff more wires just because you might have a wire hole to feed them into.
However installing a bigger box is really not that hard in this situation as some newer boxes have the box mounting screws internally - not on the outside where it would be difficult to mount in an existing installation (and yes they are screws - quite nifty for about $3.00 USA).
Your wiring might look something like this below.
Below you will find an example of the SMART box by Madison Electric
In your situation this makes perfect sense to use.} The Tabs for studs - if you don't need / use them they are removable...