Those plug sockets dotted around your home are key to powering your lifestyle, from charging your phone to boiling your kettle. But every so often, you’re going to need to install a new one. Perhaps the old one got damaged, for example. Maybe you’re re-decorating a room and want to upgrade those old white plastic ones with a brushed steel or sleek matt black model. Or you could want to upgrade your sockets to incorporate USB slots or Wi-Fi to eliminate dead zones. Whatever you’re doing, here’s a step-by-step guide to doing it properly.

Important safety and legal note on installing sockets

Clearly, dealing with electric power can be a dangerous job, and getting behind the faceplate could lead to injury, fire or damage if you don’t know what you’re doing. In law, domestic electrics are covered in “Electrical safety: Approved Document P” of the Building Regulations. It’s a fairly involved document for the layperson, but every professional electrician knows it inside out.

The relevant part for this article covers the installation of new sockets. In short, you’re not allowed by law to install completely new sockets in your home, i.e. where one does not already exist. That is to protect you, your family and friends, visitors, neighbours and future owners from dangerous workmanship. If you want a completely new socket installed, by all means buy your own parts from a reputable brand and supplier, but you’ll need to have it installed by a qualified electrician.

However, if you’re just doing a “like for like” replacement, you should be able to do it yourself as long as you are competent, and take all necessary safety precautions. What is like-for-like? That means swapping a double socket for another double, a single for a single and so on.

Sockets with extra features like USB sockets and Wi-Fi would count as like-for-like as long as they are the same format (i.e. single or double). Basically, if you’re just replacing and wiring the faceplate, you should be OK – but please do call an electrician if you’re unsure. This is bread and butter work for them, so it won’t cost much.

An exception would be sinking a socket into a wall that was previously mounted onto it, standing proud. Fixing a socket using a pattress box is simpler than knocking away masonry and skirting boards. With some wall materials (e.g. some stud walls) it might be the only option. However, because they project a few centimetres from the wall, these sockets can be quite prominent, and get in the way of furniture or doors. If you want to sink the socket into the wall using a back box, that’s a job for an electrician – it’s not a like-for-like swap.

Also, there are “special locations” – namely outdoor sockets and sockets in bathrooms – that you’ll need a qualified electrician to work on. An outdoor double socket like this one would work perfect for outdoor use, and our bathroom shaver sockets add another dimension to bathrooms.

Step by step – installing a new socket

With those legal and safety considerations covered, here’s your step-by-step instructions for changing a socket.

1. Test the power

It’s always a good idea to test the power before you start. You can do this simply by plugging in a light and switching it on, or you can use a voltage detector. There are detectors specifically designed for UK sockets, which you plug in and it gives a reading. You can leave the light or the tester switched on while you do the next stage. If the power is working, proceed to Step 2. If it’s not, you should get an electrician, as there could be a deeper problem than a faulty socket.

2. Switch off the power at the mains

Somewhere in your home there will be a consumer unit (it’s often called a fuse box). It can be anywhere, but is usually downstairs – if you don’t know where yours is, look under the stairs, near the front door, in a utility room or in its own box mounted to a wall. It contains a master switch to your whole home, but there should also be labelled switches that describe different circuits, such as upstairs lights, downstairs sockets, shower or cooker.

Switch off the circuit that you’re working on. If you have an old-fashioned fuse, remove it and keep it with you.

Make sure everyone in the home knows you’re working, and leave a note on the box – someone might think the circuit breaker has just tripped, and switch it on while you’re working.

If you left a light or tester plugged in and switched on, you’ll know the correct circuit has been switched off if the device has also gone off when you return to the socket.

3. Remove the faceplate

Using a screwdriver, undo the faceplate. There are usually two screws. Now, gently but firmly pull the faceplate away. Mains electrical wires can be quite stiff, so you might need to force it more than you expect, but if it’s not moving and the screws are completely out, there’s something else holding it in place, perhaps years of paint. In such cases you’re probably best calling an electrician, as forcing it could damage the wiring or the back box.

If there are no visible screws, it must be a “screwless” faceplate. In such cases, there are usually two plates: one that attaches to the back box, and a pretty front plate that clips over it. They are usually removed by sliding a flat screwdriver between the edge of the front plate and the wall, then gently twisting the screwdriver to prise it off. Once that’s off, you’ll see another (less pretty) faceplate that’s attached to the box. Just unscrew this as above, and continue. If it’s held in place with wallpaper or paint, you’ll have to cut it free with a knife first.

An alternative design is where a pair of flat, round caps are placed over the screws to hide them – they are hopefully not painted in place, so you should be able to remove them with a knife or even a small ball of Blu Tack.

4. Note the wiring and release it

Take a note of which wires go to the two or three terminals on the back of the face plate. A terminal is a metal component that has a hole for the wire on the side, and a tightening screw on the top to secure the wire in place. The wires should be:

  • a brown (or red) wire going to the ‘L’ (live) terminal;
  • a blue (or black) wire going to the ‘N’ (neutral) terminal; and
  • a yellow & green wire going to the ‘E’ or ‘⏚’ (earth) terminal.

Sometimes, there will be more than one of each wire, for example where the wiring continues on to another socket somewhere else in the room. It is vital that when you place the new face plate on the socket, all of these wires should be connected back to exactly the same terminals. Draw a quick diagram indicating where they all go, but note that the terminals might be positioned differently in the new socket – use the letters or symbols, not the position.

  • Brown or red → L
  • Blue or black → N
  • Yellow & green → E or ⏚

Now, with a smaller screwdriver, undo the screws holding the wires in place. When all three are released, the face plate should be completely free, and you’ll see the wires protruding from the back box or pattress box.

5. Inspect the new face plate

Closely look at the back of the new face plate, and note where the three terminals are. They will be indicated by L, N and E (or a three-line symbol ⏚ instead of a letter E). It will be difficult to see the lettering when the back of the plate is facing the wall, so make sure you know which is which.

6. Attach the wires

Unscrew the terminal screws so there’s a full gap, but not so much that the screws come out. Make sure the face plate is the right way up by placing it against the fitting. Now, manoeuvre the cables into the terminals so they correspond to the L, N and E terminals of the old plate, but don’t fasten them yet – you’re just getting the shape right and making sure they all reach. 

Starting with the brown “live” wire(s), insert the exposed metal core into the terminal hole, but make sure the plastic insulation doesn’t enter the hole. Generally, you need about 5mm (1/4″) of exposed wire. If there isn’t enough exposed wire, use strippers to take away some insulation. If there’s too much, cut the copper wire itself down a little.

Now, tighten the terminal screw firmly, but not too tightly as that can damage the wire. Tug the wire to see if it comes out. If it’s firm, move onto the blue “neutral” one and repeat. Finally, insert the yellow/green “earth” cable and tighten it up.

7. Attach the face plate

Firmly push the face plate back towards the back box or pattress box, making sure no wires are getting trapped. You might need to move one or more wires as there isn’t much wiggle room in there. Once it fits snugly in place, insert the two main screws to fasten the plate to the box.

8. Switch on at the consumer unit

Finally, switch the circuit back on at the consumer unit, or replace the fuse. If you have a tester, use this first to check there’s a current in the socket you’ve installed. Otherwise, plug in a lamp and switch it on. If it works – job done!

If it’s not working now, but it was before, the most likely issue is that a wire has come out of the connector. It probably happened when you were pushing the face plate back into place while the screw for the wire wasn’t tight enough. Repeat steps 2 and 3 above, and check for loose wires, replacing and fastening any that have come out. Then re-attach the face plate and try it again. If it’s still not working, you’ve either got a faulty socket or something else has happened, such as a wire being damaged during removal. It’s time to call an electrician.

Find the perfect sockets at ACAS Electrical

Whether you’re repairing, redecorating or upgrading, you want supreme quality sockets that look the part. We stock everything from simple, inexpensive 2-gang sockets to the latest Wi-Fi and USB-C enhanced plug sockets. Take a look at our whole collection.