In my house built around ~1970 all ceiling lamps are wired in a way where 120VAC power first enters light fixture and then hot wire proceeds through switch and return back to fixture as load wire. If I understand correctly, then somewhat newer houses built around ~1990 are wired the opposite way where 120VAC power enters first into the switch and then load wire makes a loop through light fixture. Also, there is 3rd option where 12/3 Romex extends neutral to both light switch and light fixture box.
All this time I thought it was a disadvantage to have wiring like mine, because I could not install smart light switches that usually require neutral.
However, it just occurred to me that maybe the future of smart lighting is not smart switches, but rather smart fixtures? Especially for retrofits? If I would switch to smart fixtures instead of smart switches, I could:
- eliminate almost all physical light switches in my house (currently I have to upgrade them to CO/ALR rated switches anyway)
- simply pull out some old aluminium wiring that runs behind walls as it would not be necessary anymore and my house will have less wiring in attics overall (currently I would have to trace all this wiring and replace splices with AlumiConns)
- still be able control my lights with help of voice, motion, phone or with a smart hub touchscreen as I would with smart switch. But I would not be able to have easily accessible physical switch that can turn light on or off.
I am wondering what NEC or any other electrical standards in USA have to say about this? Would it be fine to remove wall light switches altogether if the light fixture can be controlled through WiFi?
Best Answer
Lights aren't just for you
Doing this is fine for auxiliary lighting. But there must be a primary light in the room that normal humans can operate without installing an "app". That's right in the building codes, and your occupancy permit will not be issued (or be revoked) if you don't have this. I can only think of 3 ways to operate the primary light:
This may not have ever occurred to you, but you can walk into almost any room in the US or Canada and you pretty much know where to expect to find the light switch. This is hardwired into your brain at this point. And everyone else's. That is because building codes have standardized the location for those switches.
Part of this is for First Responders. You need the ambulance crew intubating you, not searching the room for the light switch so they can see to work. You want the fire department being able to clear your rooms quickly. And you want the SWAT team able to see you're holding a gaming mouse not a gun.
Part of it is also for guests. A guest confronted with your "to control lights, you need to install an app and use this password" philosophy is far more likely to grope around in the dark and get hurt. Or simply leave the lights on. Governments care about energy efficiency, and they don't like any scheme that burns lights unnecessarily. "Guests" could include domestic servants, aides, or the elderly. All in all, it makes for a very awkward conversation with your guest: "Why can't you just turn lights on like normal people?"
The wiring demands of light switches are actually pretty negligible in the grand scheme of things. I'm sorry you're finding 2-wire "switch loops" frustrating, but there are several workarounds.
Aluminum wire
The problem with aluminum wire is people's overreactions to it, and notably, the obsolescence of those overreactions.
What are we worried about with aluminum wire? To rephrase, what are we worried about with aluminum wire on connection points only rated for copper? Poor connections due to thermal expansion. How does that become a problem? Arcing. And nowadays, we have arc-fault breakers which can detect that.
So that's really the curative; switch the aluminum circuits over to AFCI breakers.
Of course continue with the CO-ALR and Alumiconn conversion, but that takes the urgency out of it.
Keeping in mind that in the LED age, lighting circuits take very little power, and can be consolidated on one breaker.
Most 1970s era panels (Challenger, Murray, Cutler Hammer, BRyant, Square D, GE, Crouse Hinds, T&B) can accept modern AFCI/GFCI breakers. If not, consider either a subpanel (to also be future main panel) or main panel replacement. If the main panel is FPE or Zinsco, make it a priority! While subpaneling, consider future generator or solar interlocks, because this can be added to a subpanel for under $40 (for QO and Siemens), and that sure beats a hokey transfer switch.