How to upgrade a plug socket

Video by Warren Nash. This walk-through is based on the video "How to Replace a Plug Socket - UK 3-pin - Easy DIY by Warren Nash", which covers the full process of safely swapping a UK socket faceplate, including photographing the existing wiring and reconnecting the terminals correctly. A calm, clear watch before you start.

1. Check what you are working with

Before buying a new faceplate, take a look at the existing socket. Most standard UK domestic sockets are either single or double gang — one or two sets of outlets on the same plate. The back box (the metal or plastic box fixed into the wall behind) will stay in place; only the faceplate changes. Make sure the back box is deep enough for the new socket, particularly if you are fitting a USB model, which often needs a deeper box than a plain socket.

Check the wiring colour too. Homes wired after 2006 use brown for live, blue for neutral, and green-and-yellow for earth. Older wiring uses red for live and black for neutral. Either is fine — just note which colour is which so you reconnect correctly. If you are at all unsure about the wiring you find, stop and call an electrician.

2. Isolate the circuit at the consumer unit

Go to the consumer unit — your fuse box — and switch off the circuit breaker for the ring main that feeds the socket you are working on. If the circuits are not labelled, plug a lamp or phone charger into the socket you plan to work on, then switch off breakers one at a time until the lamp goes off. That is your circuit.

Once the breaker is off, use a plug-in socket tester or a non-contact voltage tester on the socket to confirm the power is definitely dead. Do not rely on the breaker alone. Tape the breaker in the off position or put a note on the consumer unit so nobody flicks it back on while you are working.

3. Photograph the existing wiring

Unscrew the two faceplate screws, gently pull the faceplate away from the wall, and take a clear photograph of the wiring before you disconnect anything. This takes about ten seconds and can save a lot of head-scratching later if you lose track of which wire went where.

There will typically be three terminals on the faceplate: L (live), N (neutral), and E or the earth symbol. On a spur socket there will be one set of wires; on a ring main socket, two sets. Note which wires are in each terminal, then loosen the terminal screws and remove each wire carefully. The wire ends may be a little oxidised — a light scrape with wire strippers or a small screwdriver to expose clean copper makes for a more reliable connection.

4. Connect the wires to the new faceplate

Following your photograph, connect the wires to the matching terminals on the new socket. Live (brown or red) to L, neutral (blue or black) to N, and earth (green-and-yellow) to E. Tighten each terminal screw firmly — a loose connection is a fire risk, so make sure each wire is gripped securely and give a light tug on each one to confirm it cannot pull free.

Fold the wires back neatly so they sit tidy in the back box without being crushed. If the box is a metal type, it needs an earth connection of its own — there will be a separate earth terminal on the back box itself. Use a short piece of green-and-yellow sleeved wire (a fly lead) to link the earth terminal on the faceplate to the earth terminal in the back box. Plastic back boxes do not need this.

5. Fix the faceplate and restore power

Offer the faceplate up to the back box and push the folded wires in gently as you go. Line the faceplate up squarely with the wall — use a small spirit level if you want to be precise about it — and tighten the two fixing screws. Do not overtighten, particularly on a plasterboard wall, or the faceplate will bow in the middle.

Go back to the consumer unit and switch the circuit breaker back on. Then test the socket with a plug-in socket tester, which checks that live, neutral, and earth are all wired to the right terminals. If the tester shows a fault, switch the power off again immediately and recheck your connections against the photograph you took earlier.

6. Upgrading to a USB socket — a few extra points

USB sockets with built-in charging ports are genuinely useful, particularly in bedrooms and kitchens where people charge phones overnight. The wiring process is identical to a standard socket swap. The one thing to watch is depth — USB sockets are thicker at the back than plain sockets, so a standard 25 mm back box may not be deep enough. A 35 mm back box is usually needed. Fitting a deeper box means cutting back into the plaster or plasterboard, which is a bit more work but not a major job.

To be fair, if you are upgrading several sockets in one go, it is worth doing a quick check of all the back box depths before you order the faceplates. Nothing worse than having to make a second trip to the merchant because three of the six boxes are too shallow.

When to call a handyman

Swapping a faceplate like-for-like is well within the reach of a confident DIYer. Call Richard if you want several sockets upgraded in one visit, if the back boxes need swapping for deeper ones, if the existing wiring looks damaged or burnt, or if you simply do not want to do electrical work yourself — which is a perfectly sensible position. Get in touch and Richard can sort it quickly.