Adding a socket in the loft

I would like to add a socket into the attic, primarily for running radio kit. e.g. a couple of Raspberry Pi and/or small form factor PC and for the purpose intend to install a double socket. I have read that one can take a spur off an existing socket, but one can't take a spur off a spur. My options are limited, but I have a socket in an airing cupboard which will be used to run an Ethernet switch and/or router. This socket is spurred from a socket on a ring in the adjacent bedroom. The 2.5mm cable, which is less than a metre long is simply run through the back of the socket, through the wall and into the cupboard. The cupboard itself is on a landing and incorporated into the bathroom.

The idea is to run a new cable from the existing switched socket in the cupboard (socket2) into a switch/fuse unit and then run a cable from the switch/fuse unit into the loft and terminate with a double socket (socket3). This would mean that the sockets in the loft will be fused and capable of being isolated by means of the switch in the cupboard.

The point I am not sure of is, what is means by not having a spur off a spur? Would socket3 be viewed as a spur off socket1/socket2, or a continuation of that spur? I do get that one could not run another spur from socket2. The arrangement I am thinking of would look something like this:



I have three sockets in the conservatory which are are wired in series and run from a spur off one of the sockets in the lounge. This was done by a qualified electrician at the time but perhaps regulations have changed?

BTW, while exploring the airing cupboard while considering this, I noticed that the boiler appears to be connected under the floor to the lighting circuit. The junction box is readily accessible and the boiler is switched and fused, but is connection to the lighting circuit permitted? If not, then my installation may also need to consider re-connecting the boiler to the ring main, in which case a junction box may need to be added. The only practical way I could do this is probably something like this:



If I could get under the floor then it might be possible to disconnect the ring and feed it into a junction box under the floor, but then it would not be accessible without pulling up carpet and floorboards so I am not sure that would comply with current regulations.

UPDATE: Turns out that the boiler is connected to its own dedicated circuit so this aspect of the post can be ignored.

The fuse connection unit (spur) needs to be before the first socket.

Is the socket in the airing cupboard on the socket circuit or a dedicated circuit for the immersion heater?

Fleeting said:

The fuse connection unit (spur) needs to be before the first socket.

Click to expand...

I did wonder about that. It could be arranged that way with a bit of additional wiring. The original cable from the bedroom socket would have to be replaced with a new run from said socket through the wall and around the airing cupboard up to the switch/fuse panel. A second run would go back down to the airing cupboard socket and a third run from the fuse panel up into the loft.

Murdoch said:

Is the socket in the airing cupboard on the socket circuit or a dedicated circuit for the immersion heater?

Click to expand...

It is a spur from the socket circuit and connected to the back of one of the box room sockets.

I just checked the distribution board and found that the boiler is, in fact, connected to its own separate "Boiler Supply" circuit. I confirmed this by turning it off and observing that the light on the fuse unit and the boiler were turned off. This means the second scenario I mentioned in my opening post can be ignored.

There is also circuit marked "Landing Socket". This might have been the original immersion heater feed since the socket is on the opposite side of the landing on the outside of the bathroom wall where the immersion heater cupboard was originally located. The immersion heater is long gone and we have a combi boiler. I have just confirmed that this landing socket is indeed connected to this separate circuit.

Assuming that it is permitted ? it might be possible to run a cable from the loft down through the stud wall to this to this socket, perhaps adding a switched fuse plate somewhere if required. That might actually be a neater solution.



The socket in the airing cupboard would then remain as is - a single spur off the bedroom socket ring. Presently, it is not separately fused. Would a fuse be required?

What size fuse/circuit breaker protects the landing socket and does it have 30ma RCD protection.

The landing socket is protected my a 16A MSB. The boiler circuit is protected by a 6A MSB which probably explains the 1.5mm cable. Both circuits are on a bank protected with a 30ma RCD.

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You should be able to connect from the landing socket and being 16A would not require additional fusing assuming you use the correct size cable normally this would be 2.5.

Thank you. Yes, I would use 2.5mm cable. I might come unstuck of there's a horizontal beam inside the stud wall but otherwise this is looking like the neatest solution.

It looks like going through the partition wall is not feasible. There is a horizontal cross piece and there are both hot and cold water pipes connecting the shower within the wall that are not insulated. I have no access to be able to drill through the cross-piece without removing plasterboard. I also gather that the cable should not to come into direct contact with a hot pipe. Fortunately, existing electrics are located such that cables are routed well clear of the pipes. It looks like I will have to route the cable down through the airing cupboard and under the landing floor, but there are problems with this approach as well as I am not sure how I am going to be able to drill a hole to feed the cable up from under the floor into the partition wall.

I assume the cable for the landing socket comes up to the socket from below, if it was from above then you could insert a junction box on the cable in the loft and connect a socket there.

Yes, it runs under the bathroom floor and to the distribution board which is located in the outbuilding at the front of the house.