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Do I need a new consumer unit for 3 new smoke alarms?

Stephen Baldry

Hi. I have just had a garage conversion, and in order to get final sign off by building regs, need 3 wired and radio linked smoke alarms. 

Building regs are happy that the wired alarms use the existing downstairs lighting circuit, but I have been given inconsistent advice from the sparks that I have had quotes from. 

The existing consumer unit has a 100 Ma trip protection. Some tell me that I will need 30 Ma trip to comply, others not. Obviously that makes the cost of just 3 smoke alarms quite a bit more expensive, so I wanted to get a view from this forum. 

The alarms would be wired to the local circuit, and in the ceiling bottom and top of stairs, as well as the new room

Help would be really appreciated thanks

Steve

  • 0 in reply to aligarjon

    It’s been signed off. So I’m not worried. It’s the requirement for the smoke alarms I need advice on. 

    thanks for your help, Steve

  • 0

    I cannot see how any of the electrical work in the garage conversion can possibly comply without 30 mA RCD protection.

    But apparently it does, so as I said above get the same electrician to do the smoke alarms.

  • 0 in reply to Stephen Baldry

    So get the same electrician to install the smoke alarms.

  • 0 in reply to Sparkingchip

    Unfortunately that electrician is no longer around to help. 

    thanks for your help anyway

    Steve

  • 0

    I can actually see it would be possible to install the smoke alarms without upgrading the RCD protection, but I am really unable to see how an electrician could have certified the garage conversion without having done so.

    Merely plastering over an existing surface mounted light switch cable concealing a previously exposed cable would be enough to trigger a requirement to up upgrade the RCD protection and I can think of many more reasons why it would be required.

  • 0

    I can think of many more reasons why it would be required.

    Agreed - just addition of a new light (as it's domestic) or a new socket - would require 30mA RCD protection these days if it's to comply with current regs.

       - Andy.

  • 0 in reply to OlympusMons

    ^^^ This.
    Don't know about the rest of the country but up in Scotland radio linked devices with 10 year sealed batteries are permissible. Does away with any of the hard wiring headache. Yes, slightly more expensive than mains but not drastically (if you shop about).

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