DIY Doctor UK DIY Forums

I am trying to move a socket in my daughters room that was on an internal wall before previous occupiers built a wardrobe in the alcove. The ideal place is a couple of feet along the wall but on an external wall. I have two main questions: is it wise to move the socket to the external wall? My house was built in 1930 so I've taken the plaster coat off to the bare brick but have a feeling this may be the external wall and don't want to start bolstering the brick and damage the outside wall- the problem here is that I would need a 16mm double socket box and I don't think they exist?
Question 2 is that I have inherited some cable on a reel from an office refurb. Its a flat grey sheath but appears to have 4 wires inside coloured black, brown, grey and bare- I can't figure out what sort of wire it is and if its suitable to use with a junction box to extend the socket wiring to another part of the wall. Would appreciate any advice/clarificationb!!

The cable if from an office is likely to be Three Core and earth used in lighting systems and not for socket outlets, likely also to have a lower current carrying capacity.
There is nothing wrong with installing a socket on an external wall.
The back boxes suitable for this are 25mm and 35mm deep for this tyoe of outlet, unless you use a surface mounted box. A little more unsightly but it is an option.
My generally thoughts are that 1930's type houses had 9 inch walls so chasing out should not really be an issue. But I am making assumptions, so don't take it as gospel!
I would like to add, although you can legally carry out this work as you are adding on to an existing circuit. It will still need to have a minor works certificate. Which means the circuit will need inspecting and testing to assure it complies to BS7671 and is safe to use.
Please stay safe
KB