What Does Electrical Rewiring Involve?

domestic electrical installation

Electrical rewiring involves replacing and upgrading the electrical wiring system in a building to ensure it meets current safety and regulatory standards.

At FireCare Security and Electrical, we provide comprehensive electrical services to homes and businesses across the south coast, including electrical rewiring works.

Why is electrical rewiring needed?

Electrical rewiring is necessary to replace damaged or faulty wires that could cause equipment failure or a fire. Over time, wires can perish because of temperature changes or rodent activity, exposing live wires or causing damage. If your property is more than 30 years old and has the original wiring, it is likely to need updating, not only to reduce the risk of fire, but to meet modern electrical safety standards.

What are the employer’s responsibilities regarding electricity at work regulations?

The Electricity at Work Regulations (1989) are based on the rules regarding electrical safety in the Health and Safety at Work Act 1974, and apply to all aspects of the use of electricity within your business premises.

According to the regulations, the responsible individuals must:

  • Have the electrical systems constructed and installed in a way that they are compliant with the law
  • Conduct periodic inspections and electrical testing through a certified electrician
  • Have all electrical appliances on the premises tested under Portable Appliance Testing (PAT)
  • Teach their employees how to safely work with electricity

How do you rewire a building?

This process typically includes the following steps:


A professional electrician will first assess the existing electrical system to determine its condition and whether rewiring is necessary. Older buildings with outdated wiring may require rewiring due to safety concerns or to meet the requirements of modern electrical appliances and systems.

Planning and Design

The electrician will create a rewiring plan that outlines the scope of work, the location of new electrical outlets and switches, and the type of wiring to be used. The plan should comply with current UK electrical regulations, such as the IET Wiring Regulations (BS 7671).

Disconnecting Power

Before starting the rewiring work, the electrician will disconnect the power supply to the entire building to ensure safety during the process.

Removal of Old Wiring

The existing electrical wiring, including cables, switches, outlets, and distribution boards, will be removed. This may involve opening up walls and ceilings to access the wiring.

Installation of New Wiring

New electrical cables, such as PVC-insulated twin and earth cables, are installed throughout the building. The electrician will connect these cables to sockets, switches, and distribution boards according to the rewiring plan.

Earth Bonding

An important part of the rewiring process is ensuring that all metal components of the electrical installation are properly earthed to provide safety against electric shocks.

Installation of New Fixtures

New sockets, switches, and light fixtures are installed according to the rewiring plan. These should comply with current safety standards and regulations.

Testing and Inspection

After the new wiring is in place, the electrician will conduct a series of tests to ensure that the system is safe and functioning correctly. This includes checks for insulation resistance, continuity, and fault protection.


Once the rewiring work is complete and has passed all safety checks, the electrician will issue an Electrical Installation Certificate (EIC) or a Minor Electrical Installation Works Certificate (MEIWC), depending on the scope of the work. These certificates are important for documentation and compliance purposes.


If the rewiring work is extensive or involves changes to the consumer unit (fuse box), the electrician should notify the local building control authority or an approved inspector to ensure that the work complies with Building Regulations.

What is the risk to the business if rewiring isn’t done when required?

Electrical rewiring is a complex task that should only be carried out by a qualified and registered electrician. It is important to ensure that the work complies with all relevant regulations and standards to guarantee the safety of the electrical installation in your property.

Failing to replace old or faulty wiring in your commercial property could not only lead to injury or a fire, but could also cause inflated energy costs and unexpected bills for appliances that are damaged by the deteriorated wiring.

If you’re looking to upgrade or replace your existing electrical wiring in your home or commercial property, FireCare can help. Contact our friendly team today to arrange a visit with one of our professional, experienced electricians.