Some comments on the replies so far (constructive, not carping):
Another option would be a small concrete or grp trough laid on the ground at the base of the fence - OK if you have plants and shrubs etc most of the way along, so you don't really see it.
My preferred design is a switchfuse at the house, connected to the meter tails, supplying the cable to the outbuilding, and a CU there. As I said - no connection between outside and the house CU.
Not ideal - if anything in the shed causes tripping then you've got to schlep down there to sort it out, or back to the house to reset the RCD. Better IMO to have no connection to the house RCD protectionIt should be protected by RCD, but the consumer unit one if fine if fitted.
And the potential Zs with 30m of cable added.A qualified electrician should put a lot more thought in to the design though given potential load on the circuit.
Or if it were a new circuit from a switchfuse.One of the very few things which remains notifiable in the installation of a 'new circuit'. As has been suggested, if it were a 'new circuit' (coming from your CU), it would therefore be notifiable,
If you decided to go by the 'notifiable' route, it would probably make no financial sense to do it yourself, since you could then end up having to pay £xxx of notification fees - an expense you would avoid if a 'registered' self-certifying electrician did the work (who can notify him/herself for a few pounds).
Mine too.Regarding the fixing of the cable, you can either fix it to a permanent structure (not a fence, but if it has concrete posts it would be OK in my non professional opinion.)
I actually think it should be deeper under concrete, not shallower, because of the possibility that someone might use a breaker or digger of some sort to remove the concrete in the future.Or you can bury it, preferably at the edge of the garden or where digging is unlikely, with some marker tape a couple of hundred mm above it. Should certainly be more than a spade depth down unless it's under concrete or something.
Another option would be a small concrete or grp trough laid on the ground at the base of the fence - OK if you have plants and shrubs etc most of the way along, so you don't really see it.
Armoured cable would be required whatever the source.I'd only fit a CU in the shed if the circuit was dedicated for the shed and came directly from the main house CU via armoured cable, sorry i did not make that clear.
My preferred design is a switchfuse at the house, connected to the meter tails, supplying the cable to the outbuilding, and a CU there. As I said - no connection between outside and the house CU.
It would have to be steel - 100' of PVC conduit on a garden fence will look gashI like things in Conduit .
Bear in mind that winston has a bonnet full of bees, one of which leads him to pretty much conflate "don't need a CU" with "should not have a CU".I see what you mean winston1 .