You are reading a single comment by @NotThamesWater and its replies.
Click here to read the full conversation.
London Fixed Gear and Single-Speed is a community of predominantly fixed gear and single-speed cyclists in and around London, UK.
This site is supported almost exclusively by donations. Please consider donating a small amount regularly.
NotThamesWater
DISCLAIMER ABOUT ALL ELECTRICAL DISCUSSION: I DON'T KNOW WHAT THE FUCK I'M TALKING ABOUT...
With the building sealed, the ceiling insulated and boarded, and the floor laid, it was time to think about power.
In a previous shed project when I was living back at my mums I had wired together a few sockets and a fluorescent strip light and simply ran this all into some standard electrical cable with a plug on the end. Whenever I wanted to use the shed I would drop the plug out of the window and plug it into the house's outside socket.
Surprisingly, I never had any problems with this bodge method, and my teenage self frequently sat in there late at night with the lights on, with an electric fan heater on, getting really stoned and watching skate videos on the TV/VCR, even boiling a kettle at times for tea.
However, I wanted to do things a little more properly this time round. I was unlike to put much draw on the power out there, I have a few workshop tools (band saw, pillar drill etc) but mainly my power tools are on 18v battery now, and so charging would be the main concern, along with lights. However, I did want to future proof the space thinking future house owners might want to use the cabin as an office, gym or whatever.
So, while building the cabin my plan had always been to get a professional in to do it properly — run a new ring off of the house's CU, with it's own protection and sufficient power.
When I actually finished the cabin we were deep into lockdown and I was months out of work, and so I had to rethink this. I tried to research the process of 'doing it properly' myself, but generally DIY and constructions forums where people ask these sorts of questions are overrun by Electricians arguing about cable capacities and making it abundantly clear to amateurs that electricity is kin to magic and cannot be fathomed or manipulated without the correct qualifications. Eventually I found a suitably knowledgable friend though, and he advised me that running power 'properly' with correct protection and directly out of my house's CU was actually pretty easy, not that dangerous is a certain logical process is followed, and quite good fun.
Step 1.
My house CU was at capacity, with no slots left for new MCBs or RCDs. So, I bought a 1-way shower CU from screwfix and there was exactly enough space for this in the cupboard next to the existing house CU. I just installed it on the wall at this stage and didn't wire anything in.
This unit has a 63A RCD where I would bring the power in from the main CU, and then a 40A MCB from which I would run the power out to the shed.
It is about 50m from here to the shed and the CU in the house is on an internal wallso routing the cables was going to take some though, but I though I'd get the shed wired and ready first...