ceiling rose & junction box questions

[CChris]

Can anyone advise if a celing rose type cable layout is mandatory with a new install or rewire, or at least do the junction boxes need to be easily accessible (i.e. no punching holes in ceilings or lifting carpets?

The reason for my question is that I'm embarking on fitting remote switches to the lights in the house as part of a project to install various home automation, and I need access to the wiring.

These switches "can" work in a 2 wire setup, and simply use the live and switched live at the wall switch. However during my testing of the device on a small test board I knocked up, it did not perform very well and had a few issues when powered inline with the light/load. When I wired the device with access to a permanent neutral and live, these issues went away.

So I thought to myself, no problem Ill install them at the ceiling rose for each room using the permanent feeds.

I removed a couple of ceiling roses (upstairs rooms) and was greeted with just the switched live and a neutral feeding the blocks in the ceiling rose for the lamps (bog standard pendant fittings as we havent got round to changing yet).

This is in a newly constructed extension in the last 18-24 months. The rest of the house had a total rewire at the same time.

I have not yet tried removing the ceiling rose and giving the cables a tug to see if a junction box makes itself present.

Would the junction box being in the loft count as accessible? Not boarded over, but most likely buried under insulation.

I'd just like to be in possession of the facts before I ask the electrician back.

Im at work at present, but when I get back, Ill try a downstairs fitting and see if all the wires are present.

Many thanks in advance for any advice.

 

[bernardgreen]

Putting "active" devices above ceilings to control lights does work but it can create problems with access when the active device needs changing to update or repair.

If you are going to commit to home "automation" then condsider wiring all the lights back to a central location where the active devices can be mounted together and in an easily accessible location. Uses a bit more 1 mm² twin and earth cable but will make life easier when things go wrong.

This is the trial install in my cottage where all the lights are controlled by the bank of relays. It allows for ELV (12 volt) switches to control the mains to the lights.

Untitled

• bernardgreen
• 26 Mar 2015
• 3

 

[CChris]

Thanks, though unfortunately I didn't consider this level of automation at the time of the rewire, if I had, then wiring back to a central location would have been number one priority.

However, its all in now, house decorated, carpeted and an easy retrofit is really the only option I have.

I appreciate that getting to devices afterward needs to be as easy and hassle free as possible, which is why fitting at the switch was what I intended, but after a test, they seem a little "flaky" when wired this way. Requiring more than a little messing around with. Whereas wired with a permanent feed they behave very well. Id rather have to go in the loft once every year for the odd replacement, than be taking switch boxes off decorated walls every other week.

I suppose at least if I can access the wiring in the lofts (there are three lofts to the house), then I could make it easier in future by mounting all these radio switches in one place and running cables from each light circuit to them. However that will be notifiable, so I'd have to get the electrician in to do all that anyway. I know its simple enough to run the neutral, live and switched live for each light to a central location using 3 core and earth, but still I'd rather have the work signed off. Inserting a Zwave relay/dimmer into a circuit without modifying the mains wiring I'm OK with.

I guess the only way Ill find the answer is to take a look in a downstairs ceiling rose and see if the ceiling rose wiring presents itself.

 

[LearningSpark]

If you only have switched live and neutral at the ceiling rose you may have all the connections you require at the light switch, have you tried removing a switch to see what cables you have there?