Domestic extention and smoke alarms

[Dunk17]

Afternoon all,

Ive looked at the building regs but can't seem to find anything, i remember reading something that said when fitting smoke alarms off a lighting circuit you need to put some form of isolation in, is that correct?

I'm also looking to install nest alarms, do they all need to be wired?

Thanks for your help.

 

[Risteard]

I'd run smokes on their own circuit.
The reason being if the lights are ever isolated for whatever reason i.e light fitting change, earth fault etc, you still have that smoke alarm in operation if anything goes wrong.

But then again I'm only a trainee myself. ???

ZippyMo

They have a battery backup so remain in operation on a lighting circuit when it's isolated or switched off also.

 

[pc1966]

If the alarm circuit does not need RCD protection (say wired with Flexishield wire, or very sure the route is never behind walls less than 50mm from surface) then using a MCB would probably be less likely to trip off accidentally on some surge, etc, and not be reset.

 

[AJshep]

I'm not a fan of Nest products. Although the Alarms offer nice features like a fancy app and self test feature. Googles buisness model is data. Firms like Aico have no hidden agenda.