Tools and Materials Needed:

  • Double socket outlet
  • Back box (surface-mounted or flush)
  • Electrical cable (typically 2.5mm² twin and earth for ring mains)
  • Cable clips
  • Wire strippers
  • Screwdrivers (flathead and Phillips)
  • Voltage tester or multimeter
  • Pencil and spirit level
  • Hammer and chisel (for flush mounting)
  • Drill with masonry bits (if mounting on brick/concrete)
  • Electrical tape
  • RCD (Residual Current Device) for safety

Step 1: Planning and Safety

Before beginning, switch off the main power supply at the consumer unit (fuse box). Use a voltage tester on nearby sockets to confirm there is no live power. Plan your socket’s location — it should be at least 450mm above the floor (in new builds, per UK Building Regulations) and in a place convenient for use.

Step 2: Choosing Mount Type

You’ll either mount the socket flush (recessed into the wall) or surface-mounted (box sits on the wall).

  • Flush Mounting: Requires cutting into the wall to install the back box.
  • Surface Mounting: Easier; the box is screwed directly onto the wall.

Step 3: Install the Back Box

For Flush Mounting:

  1. Mark the outline of the back box on the wall using a pencil and level.
  2. Chisel or cut out a neat hole in the wall.
  3. Drill holes and insert wall plugs for fixing screws.
  4. Feed the electrical cable through the entry hole in the back box, then screw it into place.

For Surface Mounting:

  1. Screw the surface box directly to the wall at the marked spot.
  2. Use cable trunking if necessary to hide cables.

Step 4: Running the Cable

Run 2.5mm² twin and earth cable from the existing ring main or the consumer unit (if it’s a new spur or circuit). The cable should be clipped securely and follow safe routing zones (horizontal or vertical from sockets or switches).

If you are adding a new socket to a ring main, ensure:

  • The cable joins the circuit at two points (in and out).
  • It complies with load limits and electrical regulations.

Alternatively, for a spur, connect it to a fused connection unit (FCU) with a 13A fuse.


Step 5: Wiring the Socket

  1. Strip about 10–12mm of insulation from each conductor (live, neutral, earth).
  2. Insert the brown (live) wire into the L terminal.
  3. Insert the blue (neutral) wire into the N terminal.
  4. Insert the bare copper (earth) wire into the E (or ⏚) terminal. Use green/yellow sleeving if not already present.
  5. Tighten all screws firmly, ensuring no copper is exposed and wires are secure.

For a double socket, both sides are internally linked, so only one set of connections is needed.


Step 6: Final Checks and Testing

  1. Fit the socket front to the back box and screw it in.
  2. Double-check all connections.
  3. Turn the power back on at the consumer unit.
  4. Use a socket tester or multimeter to verify proper wiring and operation.

Step 7: Safety and Compliance

  • Ensure that your installation meets local electrical regulations.
  • All new circuits or significant additions in the UK must be Part P compliant and notified to your local authority unless done by a certified electrician.
  • An RCD is required for safety, especially in kitchens, bathrooms, or outdoors.

Conclusion

Installing a double socket from scratch is a manageable DIY task for those with basic electrical knowledge. It involves careful planning, correct wiring, and strict adherence to safety practices. When in doubt, always seek professional help — electricity is not something to take chances with.