Do you need a (wired) light switch?

[mjsx]

My house has lath and plaster walls, and so has a bunch of ugly approaches to getting cables and switches to where they need to go: mini trunking, cables behind skirting and sockets in skirting, etc. I was thinking a lot of this could go away with smart bulbs (e.g. Hue) and wireless switches.

 

Are there any particular downsides or building reg etc. issues to doing away with light switches, and basically having the lights powered connected to power, and controlled by a wireless switch? The switch could then be permanently surface mounted where the wired switch would usually go, so everything works as expected, but with a lot less chasing of cables into walls required. Crazy idea?

[Adsibob]

44 minutes ago, mjsx said:

My house has lath and plaster walls, and so has a bunch of ugly approaches to getting cables and switches to where they need to go: mini trunking, cables behind skirting and sockets in skirting, etc. I was thinking a lot of this could go away with smart bulbs (e.g. Hue) and wireless switches.

 

Are there any particular downsides or building reg etc. issues to doing away with light switches, and basically having the lights powered connected to power, and controlled by a wireless switch? The switch could then be permanently surface mounted where the wired switch would usually go, so everything works as expected, but with a lot less chasing of cables into walls required. Crazy idea?

Smart bulbs use a small amount of power even when switched “off”. If every bulb in your house was a smart one, not only wood that cost a fortune in bulbs, but you would have a bit more energy consumption.

 

 Also, wouldn’t you spend a fortune on batteries for the switches?

[ProDave]

Lath and plaster has a cavity stud wall behind it.  Surface mount switches with the wires in the cavity should be possible.

 

the problem with lath and plaster is it is near impossible to flush mount switches and sockets.  But if you are happy with surface boxes it should be possible to hide the wires inside the wall.

[TonyT]

Not crazy at all

quinetic receivers and wireless switches will give you a normal looking install!

[Gus Potter]

59 minutes ago, mjsx said:

Are there any particular downsides or building reg etc. issues to doing away with light switches,

Interesting question..

 

Gut feeling is you need to study the regs in detail.. and also refer to BS 7671 .. IEE the wiring regs and the safety regulations.

 

Personally I would avoid it like the plague.. as soon as the power goes off you'll need to reset them all and BC I think will have something to say about that.

 

I get the home automation thing but remember you may wan't to sell your house later to someone that is less tech savvy.

 

 

[mjsx]

52 minutes ago, Adsibob said:

Smart bulbs use a small amount of power even when switched “off”. If every bulb in your house was a smart one, not only wood that cost a fortune in bulbs, but you would have a bit more energy consumption.

 

 Also, wouldn’t you spend a fortune on batteries for the switches?

 

Hue bulbs are under 0.5w when off so that's £1.50/year which is not great but okay.

 

I was worried about batteries too (for cost and time and landfill waste reasons) but there are Hue switches (EnOcean) that are powered by kinetic energy (no battery). And @TonyT mentioned http://quinetic.co.uk which seem similar.

 

So I'm kinda comfortable with the energy consumption side of things. The other aspects though…

[andyscotland]

47 minutes ago, Gus Potter said:

Gut feeling is you need to study the regs in detail.. and also refer to BS 7671 .. IEE the wiring regs and the safety regulations.

 

I can't think of a 7671 reason that would prevent it. If there was then the large numbers of commercial buildings & hotels etc with lighting controlled by scene controllers/virtual switches/touchpads etc would be noncompliant. Or for that matter spaces where the lights are controlled entirely by e.g. motion detectors with no direct manual control.

 

7671 is concerned with two main things:

 

* Isolation in emergency/for maintenance. Usually in domestic that would be by the circuit breaker at the consumer unit (strictly speaking you could argue there should be a mechanism to lock it off if the consumer unit is not in same room as the fitting, to avoid the risk of accidentally turning back on while someone is working on it - but in practice I think most people assume that the small number of people/communication in a house is likely to be adequate protection). BS7671 doesn't actually allow a normal lightswitch to be considered as an isolation or emergency switching device. And even if the switch type was approved, it is very common in UK domestic to have live conductors at the ceiling rose/fitting even when the light is switched off, so isolating the entire circuit at the consumer unit is the only real option.

 

* Functional switching - the requirements here are much looser (basically just about what users need) and the regs specifically allow for controlling the current without having to actually connect/disconnect the circuit e.g. electronic controls. Functional switching is only required if there is a need to control part of a circuit independently of the rest of the installation.

 

So from that perspective so long as you have some means to turn lights on and off in whatever combination suits you as the user, the electrical regs are satisfied.

 

47 minutes ago, Gus Potter said:

 

Personally I would avoid it like the plague.. as soon as the power goes off you'll need to reset them all and BC I think will have something to say about that.

 

This is a very good point. Any system that isn't essentially failsafe - e.g. the lighting "just works" again after a powercut - may pose safety concerns that you would need to solve.

 

To be honest, I am quite a fan of having standalone battery-backed emergency lighting in homes, I think the argument against requiring it is that occupants will be more familiar with the layout than in eg. a public space, but try to stumble out of bed and out of the house in the dark without tripping over something and you may think again, especially with kids! There are plenty of not-ugly options these days and/or smoke detectors with escape lights built in that I would consider.

 

47 minutes ago, Gus Potter said:

I get the home automation thing but remember you may wan't to it sell your house later to someone that is less tech savvy.

 

Very wise to consider that, or that you may have guests/a home exchange. And indeed that you may find your chosen manufacturer goes bust/drops support for all your kit/is inspired by car manufacturers to pivot to charging a monthly subscription to "enable" the kit you already own.

 

So I would definitely be cautious with anything too "fancy", definitely not something that can only be controlled from a phone app or some proprietary home assistant type thing.

 

But any of the kinetic energy based switch solutions are pretty foolproof I would say, certainly Quinetic stays configured after loss of power. So from a regs point of view they still provide the required functional switching and from a user point of view they are basically "fit and forget" - a guest / future owner might never even realise there's no wires behind the switch on the wall.

 

Personally I would go with a kinetic energy switch with a relay/dimmer box & stick to a standard "dumb" lamp - I'm fairly suspicious of smart lamps as my experience (admittedly not recent) has tended to be that mixing electronics and lamps doesn't end well as they tend to overheat and die, and it anyway feels very wasteful (cash and environment) to shove more and more electronics into what will always be a consumable.

 

Obviously it's fairly likely as an electronic component the switch will fail and have to be replaced sooner than an old-school switch. But IMO that's not that different to a dimmer switch - it's pretty common to have to replace them and people still seem to prefer them over a basic on/off.

 

[Gus Potter]

3 minutes ago, andyscotland said:

I can't think of a 7671 reason that would prevent it.

Thanks Andy.. given me food for thought.. every day is a school day.

[andyscotland]

Just now, Gus Potter said:

Thanks Andy.. given me food for thought.. every day is a school day.

 

I felt given the time & detail you put into your answers and the food for thought I get reading them that you deserved a considered reply 🤣

[Onoff]

7 hours ago, Gus Potter said:

Personally I would avoid it like the plague.. as soon as the power goes off you'll need to reset them all and BC I think will have something to say about that.

 

 

Erm...no you don't, at least not the Quintetic ones I have here. There's no going up into the ceiling / loft and having to re-pair the switch to it's receiver.

[RobLe]

9 hours ago, Adsibob said:

 

 Also, wouldn’t you spend a fortune on batteries for the switches?

We have a wireless front doorbell switch.  The outdoor unit power is scavenged from the act of pushing the button, no batteries required.

[SteamyTea]

8 hours ago, mjsx said:

Hue bulbs are under 0.5w when off so that's £1.50/year which is not great but okay.

My lightbulbs are 3W, when on.

I usually only have one at a time on.