DIY Doctor UK DIY Forums

Hello all,

I have recently removed our electric shower and swapped it out for one that runs off the combi boiler.
I am left with a 10mm cable on a shower supply from the RCD consumer unit. It is still attached to the pull chord with orange light bathroom shower switch which at the moment lives above the bathroom in the loft.
My questions are.....Can I use this supply to power a double socket (or two) in the loft and maybe relabel the consumer unit to suit...If so is it take a feed to a junction box first or wired direct from the switch, I am happy to use the switch to isolate the loft space anyway, The loft isn't used as a room, just for storage. I would also like a light in the loft too but I can just use a plug in one if necessary (not so important). Initially I don't want to call an electrician, I would rather have an idea of what's involved and maybe a rough cost before phoning a pro.
Thanks in advance

No reason why it should not be used. Either lollipop ring final or radial, but sockets normally supplied by a 16 to 32 amp overload, where a shower could be up to 45 amp, so it may need changing.

The problem you are going to have is getting a 10mm cable into a socket.
If you are thinking of putting a junction box on the cable and running smaller cables (That will fit into a socket) that becomes a major fire risk. The problem is that your shower probably has a 40A MCB on the other end of the 10mm cable (That is perfectly acceptable) but if you then change the cables to (For example) to 2.5 mm that then means the 2.5mm cables are protected by a 40A MCB where it should be a 20A MCB, so if there is a problem the weakest part fails, which in your case will be the 2.5 cables. The way round it is to have the 40A MCB changed to a 20A MCB

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