Garage cabling advice needed

[newman]

What type of cable will be required to provide power to a separate garage? The total cable run is 15m and it will be underground. It is intended to power a 13A socket and a fluorescent lamp. The supply will be from a spare breaker in the house consumer unit.

Regards

[Sparks]

For 15m, buired underground, for the load you suggested, you would need

2.5mm SWA-XPLE cable like this. will also need some brown, blue and green and yellow sleeving for each end, as the cable colours are not correct for single phase. will need some glands to terminate the cable, like these 2.5mm or 4mm cable cable glands are indoor ones, I assume you will be taking the armourd cable from the house consumer unit to inside garage, directly. If you want to terminate the armoured cable outside, you need external glands 2.5mm or 4mm can terminate in the garage, in one of these plastic box with 20mm knockouts)

Then run two FCU's off of it (with 2.5mm cable)

woth a 13A fuse, then connected to your socket the other with a 6A fuse for your light (If you only have one light, you could use a switched one like this, so you dont need an additional light switch then need to run 2.5mm cable from your socket to the 13A one and at least 1.0mm cable from your light, to the 6A one.

If you don't have an RCD in the house, you will need one of these for your socket

socket with integrated RCD)

If you do, then you only need one of these

double socket)

The other, better way to do it, is using a second consumer unit. This will allow you to expand later (maybe you have a shed that may need power, maybe you will need more power in the garage later etc..

If it were me, and it involved digging, I would go for 4mm or even 6mm in case you want to add to the installation later...

4mm is best to connect this to a non RCD circuit in the house, then install a consumer unit in the garage with a 30mA RCD, like this (I have suggested a metal consumer unit, so you can attach the gland to it directly)

You need to use an appropriate rated MCB in the house, depending on your cable size. (This is assuming you use an additional consumer unit in the garage) I would suggest the following..

2.5mm - 20A 4mm - 32A 6mm - 45A

Then there is the earthing requirements, do you know how you house is earthed at the moment?

Part P will apply here.

[newman]

Thank you very much for the comprehensive advice. My main task is to get the cable run in before kitchen [where the consumer unit is located] renovations. I think I will go for the 4mm option. Can this be run sraight into a new consumer unit in the garage?

Regards

[Christian McArdle]

I would suggest going for 6mm.

The 6mm could, as it will run a 32A circuit, which makes it a submain worthy of a consumer unit.

Christian.

[newman]

I don't envisage 32A being needed. The garage sockets will power a lawnmower and a freezer.

Regards

[newman]

I don't know the main earthing but would expect it to be via the incoming supply cable sheath.

Regards