Adding extra sockets to a room (flush-mounted)

6 May 2008 | Category ElectricWiz | No comments »

If you’re constantly using trailing sockets or adapters to run your electrical appliances in a particular room, then it’s time to look at adding extra wall sockets.

The good news is that in most cases it’s a relatively easy job to do this, and – at the time of writing – you don’t need to notify the job to the council under Building Regulations, as long as you’re adding the sockets to an existing radial circuit, ring circuit or spur and not direct to the consumer unit.

NB – There are important exceptions to this!

  • Work carried out in a kitchen, bathroom or outdoors must ALWAYS be notified.
  • The only sockets allowed in a bathroom are low-power ones for electric shavers, and there are stringent regulations as to where they may be located.

We strongly advise against undertaking your own electrical work in any of these locations.

In any event, it’s a sensible step to get your work tested and certified for safety afterwards – to ensure that your building and contents insurance is still valid and that the work doesn’t cause a hitch if you come to sell the house.

You can choose two basic ways of mounting your new socket: surface-mounted or flush-mounted.

Flush-mounted sockets

Flush-mounted sockets are a little more tricky than surface-mounted ones because you’ve got to cut away part of the wall to fit the metal mounting box inside. But they’re much tidier.

Plasterboard

If you’re fixing to plasterboard, it’s relatively straightforward. Draw or trace an outline of the box where you’re planning to fit it, and drill a hole in each corner big enough to fit a padsaw blade into. Then cut along the lines of the outline and remove the plasterboard. Remove the cable entry hole you’re using (probably the bottom one, unless you’re running the cable from the ceiling) and fit a rubber grommet, then feed in a 75mm (3″) loop of cable.

Clip dry-wall fixing flanges onto the sides of the box. Put one side of the box into the recess, then (being careful not to drop the box!) ease the box into position so that both flanges are behind the plasterboard and the box fits nicely in the hole. Finally, wire and fit the socket (see below).

Lath-and-plaster

Slightly more complex because of all the wood you’ll need to cut through.

If possible, try to position the socket over a stud or a nogging. You may find you have to chisel a notch into the stud to get the box flush with the surface of the wall; keep trying the box against the stud until you’ve removed enough wood. Fit a grommet over the cable entry hold and feed a 75mm (3″) loop of cable into the box, then screw the box to the stud or nogging and wire the socket.

Otherwise, you’ll have to remove a lot more lath-and-plaster to enable you to fix a nogging between two studs – and you’ll have the problem of making good the plasterwork afterwards.

Masonry

This is a laborious task rather than a genuinely difficult one. You’ll need to chop away the brickwork, not just to make the hole for the socket box, but also to create a “chase”, or channel, for the cable by cutting away the plaster down to the brickwork.

When making the hole for the socket box, the best way is to cut away the plaster where you intend to position the socket, then drill several holes in the brickwork to a depth such that the box will sit flush with the wall. Try the box in the hole. It it’s a good fit, make marks through the fixing holes and remove the box, then drill the wall and fit No.8 plugs. If it’s loose or if the hole’s too deep, remove the box again and put in a little filler, then replace the box so that it fits correctly. After 10 minutes, carefully take the box out again and allow the filler to set, then drill the wall and fit plugs as above.

Choose which cable entry hole you’re going to use and remove the blank, fit a grommet, feed a 75mm (3″) loop of cable into the box, then screw the box to the wall. Plaster around the box and over the cable; once it’s set, you can wire and fit the socket.

Wiring and fitting the socket

This is straightforward. You’ll need to use new-style wiring cable with a brown insulated live wire and a blue insulated neutral wire. The bare wire in the middle of the cable is the earth wire; you should insulate this yourself with the correct green-and-yellow sleeving.

The brown wire goes into the hole marked “L”; the blue wire goes into the one marked “N”, and the earth wire goes into the one marked with the letter “E” and/or the earth symbol. Strip off just enough insulation to ensure that a connection is made; if you strip away too much, then either snip the wire shorter or fold it back on itself. Make sure the terminal screws are tight.

You may have to bend the individual wires (which are quite stiff) to allow the faceplate of the socket to close. When you’ve done that, tighten each fixing screw bit by bit until the faceplate is securely fixed to the wall or the box.

Once you’ve done that, you’ll be ready to connect your socket to the mains.

Surface-mounted sockets

Surface-mounted sockets are much more straightforward to add as all you have to do is drill a couple of holes and fix the box to the wall using screws and wall plugs, though they can look a bit unsightly. We’ve got another article that tells you how to mount sockets on the surface of the wall.



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