Earthing and Bonding

Earthing and Bonding

It is our duty as a registered electrician to check the earthing and bonding on any installation is suitable and meets current electrical regulations. The safety of any new installation at your property (no matter how small) will depend on the earthing and bonding arrangements.

Suitable earthing is in place to protect you from a potential electric shock. It achieves this by providing a path (a protective conductor) for a fault current to flow to earth. It also causes fuses or circuit breakers to switch off the electric current immediately to the circuit which has the fault.

A great example of this would be a kitchen hob with a live cable which had come loose and was touching the metal hob casing. Providing the casing was earthed the fault current will flow to the earth through the protective (earthing) conductors and cause the fuse/MCB’s to trip. If however it wasn’t earthed, the metal casing would have stayed ‘live’ and given anyone who touched it a very unpleasant shock.


Bonding is installed to negate the risk of electric shocks to anyone who may touch two different metal parts when there is a fault somewhere. By installing supplementary bonding conductors between specific parts of the installation, we can reduce the voltage significantly.

The types of bonding generally used are main bonding and supplementary bonding.

gas earth bondingMain bonding

Green and yellow conductors (wires) that connect different metal service pipes (gas, water and/or oil) from inside a building to the main earthing terminal of the electrical installation.

Supplementary bonding

Green and yellow wires that connect metal parts of electrical equipment which is accessible (such as a heated towel rail) to other accessible metal parts electrical equipment and/or accessible metal parts of items that are not electrical (such as pipes). These connections are made in order to prevent a dangerous voltage between two accessible metal parts, if there was ever a fault. You may find that you need supplementary bonding within rooms which contain a bath or a shower, except in situations where all circuits in the room are protected with suitable RCD and the main bonding is up to the required standard.

The two most important things to consider are:

1.         Is your homes electrical installation correctly earthed

2.         Do you have the correctly rated and functioning protective devices in place

If you are concerned about your Earthing and Bonding and are based in Leigh and the surrounding areas. Please get in touch by calling us on 01942 565 657 or alternatively send an email to