Working with the new wiring regulations

Note: the new regulations apply only to domestic cable. Flex, or flexible cord, wire colours will not be changing. Flex is used to connect electrical appliances to the fixed wiring, and is coloured brown for live, blue for neutral and yellow/green for earth.

Tools & materials

Before commencing work, make sure you have all the tools & supplies you need to successfully complete the job. Use the following link for a list of basic electrics tools and materials:

• Basic electrics tools & materials

Working safely

Before beginning any work with electrical cables, you must ensure you always take the following precautions;

• Switch off the main power at the fuse box.
• Isolate the circuit you intend to work upon by removing the fuse and placing it somewhere safe. If the fuse cannot be removed then simply tape the circuit breaker in the off position.
• Ensure the circuit is indeed dead by using a socket tester (for sockets) or a voltage tester (for a lighting circuit).

When you have finished your job replace the fuse/circuit breaker and turn the mains switch to the on position. Remember, always attach the covers/faceplates to all fittings before restoring the mains power.

‘Two core and earth’ cables

This is the simplest of domestic cable where the live wire is separately insulated (in red) from the neutral wire (in black), with the earth wire running unprotected between the two. When old and new cables are joined at a socket, or with junction box terminals, the correct colours must be connected. This means connecting old red to new brown (live wire) and old black to new blue (neutral wire).

‘Three core and earth’ cables

This is special cable that’s used particularly for the two way switching of lights, and consists red, yellow and blue wires, any or all of which can be live, with the earth wire running unprotected between them. The connections in two-way and intermediate light switching are designed to allow the circuit to be made or broken at any of the switching points. As with the ‘2 core and earth’ cables, always ensure that the correct colours are connected. This means connecting old red to new brown, old yellow to new black and old blue to new grey.

• Note: the brown, black and grey wires may at all times be live at a light switch, therefore they must be wrapped in brown PVC electrical tape to act as a warning flag

Further information and useful links

• Find an Electrican near you
• Find Electrical Inspection & Testing Services near you
• Find an Electrical Re-Wiring Specialist near you

• Electrical Safety (part P) (odpm.gov.uk)
• National Inspection Council for Electrical Insulation Contracting
• ELECSA (elecsa.org.uk)