Earthing and Bonding

Upgrades to earthing and bonding are essential aspects of electrical safety, ensuring that the electrical installation in a property is safe and compliant with current standards. Let’s break down what earthing and bonding are, and why upgrades may be necessary.

Earthing

Earthing is the process of connecting the electrical installation to the earth, providing a path for fault current to flow safely into the ground in the event of a fault. This helps to prevent electric shocks. It also reduces the risk of fire by ensuring that any excess electricity does not remain in the installation.

Upgrades to Earthing:

• Outdated Earthing Systems: Older properties may have earthing systems that are no longer compliant with current standards. Such as TT systems with inadequate earth rods or PME (Protective Multiple Earthing) systems that need updating.
• Improving Earth Rods or Electrodes: Replacing or upgrading earth rods to ensure a better connection to the ground. This reduces the resistance of the earth path.
• Installation of Earthing Conductors: Upgrading earthing conductors to the correct size.  This means typically using larger cross-sectional area cables, to handle fault currents effectively.

Bonding

Bonding is the process of connecting metal parts that are not meant to carry electricity (such as water pipes, gas pipes, and structural metalwork) to the earthing system. This helps to ensure that in the event of a fault, these conductive parts do not become live.

Upgrades to Bonding:

• Main Protective Bonding: This involves bonding the main services entering the building (e.g., gas, water) to the main earthing terminal. Upgrading may involve replacing old bonding conductors with ones that meet current standards (typically 10mm² or 16mm² copper for domestic properties).
• Supplementary Bonding: Used in special locations such as bathrooms. If supplementary bonding is required but not present, or if existing bonding is insufficient, upgrades will be necessary.
• Ensuring Continuity: Ensuring that all bonding connections are continuous and secure, which may involve replacing or repairing corroded or loose connections.

Why Upgrades Are Necessary:

1. Compliance with Current Standards: The requirements for earthing and bonding are outlined in the latest version of the IET Wiring Regulations (BS 7671). Upgrades ensure compliance with these standards.
2. Safety: Effective earthing and bonding significantly reduce the risk of electric shock and fire.
3. System Performance: Proper earthing and bonding improve the overall performance of the electrical system, including reducing interference and ensuring that safety devices such as circuit breakers or RCDs operate correctly during faults.
4. Changes in Property Use: Alterations, extensions, or changes in the use of a property can necessitate upgrades to earthing and bonding.

Common Indicators That Upgrades Are Needed:

• Findings from an EICR: An Electrical Installation Condition Report may indicate that upgrades to earthing and bonding are required.
• Visible Corrosion or Damage: Corroded earth rods, damaged bonding connections, or missing bonding clamps.
• Outdated Installations: Older properties, especially those with installations predating modern regulations, often require upgrades.

Ensuring that earthing and bonding are up to current standards is crucial for maintaining electrical safety in any property.