Shed wiring - need consumer unit?

I’d like to put a small light and socket in my little potting shed and an outside light with a motion sensor. Someone has suggested I’ll need a new consumer unit for these 3 things, even though the socket will hardly ever be used. Is this necessary do you think?

Asked by Sarah on 25th Mar 2021
Expert Trade Answers
Best Answer
"Is not necessary to have new consumer unit. You can take power from the nearest power
Socket to (13A FCU FUSED CONNECTION
UNIT) and then a 4mm cable in conduit to
To a wisker junction boxes inside the
Shed and from there you can take power to the lights and the socket ( easy load on the socket)
Hope that helps"
Answered on 26th Mar 2021 - Member since Mar 2017 - report
"Yes you will need an rcd fuse board as the shed will be outside the main building."
Answered on 25th Mar 2021 - Member since May 2020 - report
"Hello,
Its not necessary if you run it correctly

Run a 2.5swa to a socket and spur with a 5a fuse for your light feed."
Answered on 25th Mar 2021 - Member since Feb 2020 - report
"It depends, new consumer unit is best option as it means if any problems outside then it won’t affect your inside electrics. However you could by an rcd socket and fuse down your lights with a 5amp switched fused spur. These two combined is enough protection also."
Answered on 25th Mar 2021 - Member since Jan 2021 - report
"A new consumer unit wouldn’t be necessary unless your adding on more things in the future that will draw a lot of power. I’d recommend putting the supply on its own circuit from the main consumer unit with RCD protection and using an armoured cable out to the shed, then spurring off a small lighting circuit from your socket."
Answered on 25th Mar 2021 - Member since Feb 2020 - report
"You can extend existing circuits to the outside to sheds for example and this is allowed. However, any modifications to an existing circuit inside the property to the outside must be protected by an RCD. Another problem with this method is nuisance tripping. If you plugged an appliance into the socket in the shed such as a lawn mower and perhaps due to moisture it trips the RCD in the house then you will temporarily lose the electricity supply to half the house and perhaps all of it. A better way is to run some steel wired armoured cable from the house consumer unit to a new 2 way consumer unit in the shed with its own RCD protection. The armoured cable supplying the shed does not require RCD protection. BG manufacture a 3 way weatherproof consumer unit. It has a gasket seal on the front cover and costs around £40 to buy."
Answered on 4th Apr 2021 - Member since Jul 2020 - report
"If your only running 1 socket (depending on power usage)and 1 light then you can run this from a socket to a fused spur"
Answered on 25th Mar 2021 - Member since Apr 2019 - report
"Hey, to add a new circuit to a consumer unit it will have to meet current regs. If it has no rcd/rcbos that may be the reason they have suggested an upgrade.

Hope this helps"
Answered on 25th Mar 2021 - Member since Feb 2018 - report
"If the shed power supply is taken off a ring main to a 13amp fused spur, and then fused down again to 3amps for lighting you wouldn’t need a consumer unit as long as the circuit has RCD protection."
Answered on 25th Mar 2021 - Member since Jan 2021 - report
"It's not, but I would always suggest it to my clients as it also allows future expansion.

As others have said, it keeps it away from your supply in your home. So would defiantly put on its own circuit from your main DB."
Answered on 2nd Apr 2021 - Member since Dec 2020 - report
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