Power Cable to summer house

[Spentfuse53]

I plan on running power from the existing house distribution board (spare way) to a summer house with its own board (power and lights and possible future garden lights). I plan on having an electric oil filled radiator and we have a woodburner effect fan heater. The other power is table lamps and TV/radio etc.
Lighting will be a couple of ceiling roses.
The length of cable required between the boards will be about 30 metres.

Can anyone advise on the armoured cable I would need to use or could I use ring main cable in a plastic duct?
Many thanks

 

[EFLImpudence]

Outside power is not a DIY job.

Please employ an electrician who will tell you what to do.

 

[deadshort]

I would advise SWA 6mm 3 core .If you have water supplies in the summer house there is a raft of regs you must comply with.

Regards,

DS

 

[Spentfuse53]

Thanks for your replies. My electrician is away on a cruise but to save time and money he suggested I lay the cable and run it into the summer house for him to connect/ wire to panels when I'm ready and he gets back.

There is no water to the summer house and no gas. There might be a TV aerial in future.
I've just used Dimplex sizing calculator based upon the U values (it's fully insulated to current regs, though it's too small to need Building Regs). The size of panel heater might be up to 1.25kw. Would this affect your suggested cable sizing?

I will want the electrician to install, test and certify the electrics.

Many thanks

 

[riveralt]

Thanks for your replies. My electrician is away on a cruise but to save time and money he suggested I lay the cable and run it into the summer house for him to connect/ wire to panels when I'm ready and he gets back.

The electrician should have designed the circuit, worked out the load, voltage drop, earthing arrangement etc and provided you with the size of the cables required.
He should also have told you where and how deep to dig the channel for the cable and how much to leave open for inspection.
This type of work requires notification with the LA and the electrician has to be involved in all stages of the design, installation and testing - even if you do some of the labouring.
You need to wait for him/her to come back from their cruise.

 

[JohnW2]

Thanks for your replies. My electrician is away on a cruise but to save time and money he suggested I lay the cable and run it into the summer house for him to connect/ wire to panels when I'm ready and he gets back.

Did he not also suggest what cable you should lay, since you will presumably be expecting him to sign to say that he designed the circuit?

There is no water to the summer house and no gas.

Fair enough. How is the building constructed - are there any structural metal parts?

I will want the electrician to install, test and certify the electrics.

Other, it seems, than installing the feed cable. Did your electrician tell you his requirements for that - in terms of depth of burial, warning tapes etc? Are you going to leave the cable exposed for him to inspect when he returns from his cruise?

Kind Regards, John

 

[ban-all-sheds]

Did he not also suggest what cable you should lay, since you will presumably be expecting him to sign to say that he designed the circuit?

Other, it seems, than installing the feed cable.

Something else he will be expected to sign to say he did.

You need to wait for him/her to come back from their cruise.

 

[Spentfuse53]

Thanks for all your replies. Looks like I'll just have to wait for the electrician to get back.

 

[scousespark]

Or get another electrician.

 

[ericmark]

What you can do is think about that load. Having a 100A supply same as house clearly you could run anything that you have in the house, but as you reduce from 100A then the cost goes down. In the main we look at 13, 16, 20, 25, 32, 40, 45 amp steps those are the common MCB sizes and although you can draw over the MCB size doing so will in time cause the MCB to trip.

Since you want a consumer unit I would suggest 20A is the starting point at house with a 16A and 6A MCB in summer house.

At 30 meters 6mm sq will easy do 20 amp in fact still within limits at 32 amp using 4 mm sq then you drop to 20 amp and with 2.5 mm sq you drop to 13 amp so looking at 30 meters it is a question 13, 20 or 32 amp which in turn means 2.5, 4, or 6 mm cable.

 

[dhutch]

I plan on running power from the existing house distribution board (spare way) to a summer house with its own board (power and lights and possible future garden lights).
....I plan on having an electric oil filled radiator and we have a woodburner effect fan heater....

As soon as you start adding heaters, the cable demand goes up a lot, and certainly you will need to work out how much power you will need, which along with the length of run and where its run, will determine the cable size and type required.

Outside power is not a DIY job.

My understand is that if both ends are inside, it doesn't count under the clause. That said, your also adding a new circuit, and generally if paying a electrician anyway I agree that he should at very least be specing the cable! You could however dig the trench in the mean time, unless its being run along the fence...

Having a 100A supply same as house clearly you could run anything that you have in the house...

Lot of houses dont have a 100a feed these days!

Daniel

 

[Iggifer]

You could however dig the trench in the mean time, unless its being run along the fence...

Tut tut!

 

[dhutch]

Tut tut!

What's wrong with that!

 

[Iggifer]

Sorry I quoted more than I intended to. It was in relation to the fence bit, not the trench, that's fine

 

[EFLImpudence]

Outside power is not a DIY job.

My understand is that if both ends are inside, it doesn't count under the clause. That said, your also adding a new circuit, and generally if paying a electrician anyway I agree that he should at very least be specing the cable! You could however dig the trench in the mean time, unless its being run along the fence.

It doesn't matter where the ends are.

I didn't mean legally or any regulation related prohibition.
I just meant that DIYers do not have the knowledge or the equipment to do it.

They have to be asked every related question and told every single step.