Gargen Deck Lighting / RCD Sockets

[jamespascoe]

Hi all,

I want to run some power to my shed from the house and am would like to know if what I have in mind is sensible / will comply with the regs.

I would like to run 25 m of SWA to my shed from the house - where it will connect to a weather proof CU (in the shed). In the house, I want to connect the SWA to a fixed spur using an RCD.

The reason for using a spur is that my main CU (in the house) is full, though, I have one breaker that runs an existing outdoor light, so I guess I could hook in there if necessary.

Then, I want to run 1 RCD protected double socket off the CU in the shed. On this circuit, I also want to run some standing lights on a deck that I am currently building.

Also from the CU in the shed, I want to run a second circuit for some small low-voltage deck lights.

Do I need to use SWA to feed the deck lights, even though the cable is under the deck ?

Also, can anybody give me any advice on certification. Is it ok to put covers on / finish the deck before certification ? Also, does anybody have any idea of how much certification costs ?

Anyway, thanks very much - if somebody could give me some advice on what I have in mind, I would appreciate it.

Many thanks,

James

 

[ricicle]

Ideally the shed circuit should come from it's own circuit at the CU, maybe you could move the outside light circuit on to another light circuit (subject to loading)

What size SWA do you intend using.Will there be any metallic services entering the shed (water, gas, oil). What is the existing set up of your incoming earth at the house?

The SWA to the shed does not need to be RCD protected, and having an RCD at the house for the shed would be inconvienient in the event of a trip.Have the RCD at the shed end (30mA) and put any socket outlets on that.Lights do not need to be RCD protected.

Swa would be a good idea for the deck lights as it is a simple way of providing mechanical protection for a cable that will be hidden away and possibly subject to vermin damage.

Not sure on costs for self-certifying, best ask your local LABC, but they will like to see all the cables runs etc.

 

[Steve]

If DIYers had their way I'm sure they'd end up having 5 RCDs protecting every socket

If you're making the effort to run all that cable to the shed, do it right at the house!

Put the outside light on a spur, no RCD nessecary.

Take the SWA back to the CU.

OK, on any one socket outlet in an installation, there should only be one RCD in line to it. So your socket in the shed either has its RCD protection afforded by the house RCD, the shed CU RCD or by an integral RCD socket. You only need one!

For the deck lights, I'd use LED lamps. They are VERY low wattage and very bright for the energy they use. Search google to find suppliers and brands. You wont need a seperate circuit for these, they might even come with a "wall-wart" to plug into a standard socket.

I wouldn't use SWA for the deck lamps, but use a cable designed for outdoor use, such as hi-tuff or arctic (arctic is normally blue or yellow).

Phone your local building control on monday morning to ask about their electrical certification policy. You will have to pay a fee of around £60-100.

You dont need a weatherproof CU. Unless your shed is like swiss cheese (lots of holes).

If the loading will never exceed 13 amps, it will be fine as a spur (and the circuit on the ground floor should already have RCD protection (check this), but its always best to do things belt and braces in my opinion by having a seperate circuit.