Running power to a shed

Want to power 4 double sockets in a shed at bottom of garden – only 2 will be used at any given time but wife wants them in different parts of shed for work space flexibility. Lighting will be plug-in spotlight type. Will spur off external lights for side door of house. Will I be ok with 2.5mm twin and earth provided it’s in conduit externally? Or do I NEED rodent-proof and weatherproof armoured cable? She wants industrial style metal boxes and faceplates surface mounted on whitewashed OSB boards – it’s a look-thing darling! Can cabling go underground at any point and does it matter if the cable entry point into the shed matter if it’s high up with drop downs to the sockets, or will coming in at floor level be fine? Any of your knowledge/experiences welcome – looking do get done Sun/Mon….cheers

Are you in England/Wales ? Sounds like this is “Part P” notifiable.

Yep.

The actual rules are pretty vague regarding how the cable should be routed. It really needs to armoured (swa) and it should be buried at a depth it won’t get damaged (around 600mm) with warning tape above. In reality you will get away with doing a simpler job if you can route it safely. For example tucked into a flower bed there’s a good chance of putting a spade through it, round the back of a shed less so. For a short run above ground might be OK.

Cable needs to be sized for the load and distance so there isn’t too much voltage drop. There are tables for this. I suspect 2.5 will be fine but if you are laying swa the cost of thicker cable won’t add much cost.

Once in the shed up or down is fine. Just needs to be safe. Hidden cable in safe zones and exposed cable protected in conduit. Metal sockets and back boxes need to be earthed properly.

As for regs different rules for different parts of the uk but its generally non notifiable unless you are adding a new circuit to your consumer unit (which you should IMO but there are other ways). Definitely needs to be rcd protected and the circuit should be tested.

Rascal, do you mean you are planning on powering this by taking a spur from the outside light. If so you will probably overload the feed for this light, be it from a fused spur off the ring main or from a lighting circuit.

The actual rules are pretty vague regarding how the cable should be routed. It really needs to armoured (swa) and it should be buried at a depth it won’t get damaged (around 600mm) with warning tape above.

No requirement to bury the cable, it just needs to be ‘secured’. Mine runs along the fence Cant rails in a steel conduit for 40m. All inspected and signed off to Part P by Building Control.

Kitchen end by Ben Freeman[/url], on Flickr

More info on this thread: http://singletrackworld.com/forum/topic/power-to-shed-what-piping-hose-etc

Footflaps: your cant rails turned into a can’t rail 😯

Will spur off external lights for side door of house.

Errr no. Can’t run a power circuit off a lighting circuit.

Doing it properly won’t cost much more than bodging an unsafe job.

Are you in England/Wales ? Sounds like this is “Part P” notifiable.

What about Scotland? I’m thinking of doing similar. I’ve got 2 options, spur off existing outdoor socket or new rcd and circuit out of the fuse board. The latter requires a slightly longer cable run and drilling through the wall

It never crossed my mind it would be notifiable. An electrican will be sort to do the work, apart from digging up the garden

Footflaps: your cant rails turned into a can’t rail

That was an ‘in progress’ photo, the cant rail has since been braced with some left over 6mm steel plate.