BS 7671 Amendment 4 is expected to bring significant updates to UK electrical regulations in 2026. In this article, we provide an overview of the changes to the 18th Edition Wiring Regulations.
What is BS 7671 Amendment 4?
The 18th Edition Wiring Regulations are the UK’s national standard for electrical installation safety. Issued by the Institution of Engineering and Technology (IET) and BSI, the requirements cover the design, installation and verification of electrical systems to prevent incidents such as shocks and fires. They also ensure compatibility with new technology like EVs and solar.
Compliance is a legal necessity for professional electricians working in domestic and commercial environments.
The previous revision to the 18th Edition Wiring Regulations, Amendment 3, was published in 2024. BS 7671 Amendment 4 is planned to harmonise UK standards with Europe.
The public consultation on Amendment 4 has closed, and the NICEIC, the leading certification body for the UK’s electrical contracting industry, will provide further information when the final version is released.
Please note that Amendment 4 will be the final update to the 18th Edition Wiring Regulations and will be replaced by the 19th Edition in due course.
What are the changes?
BS 7671 Amendment 4 is urgently required, as the UK’s electrical regulations need to respond to a wave of rapidly evolving smart technology now available on the market. For example, the revisions will cover integrating renewables (i.e. batteries and generators), Power over ethernet (PoE), ICT earthing, energy efficiency and smart home devices (i.e. EV charging and data cabling).
Here are the new sections included in BS 7671 Amendment 4:
Section 545 functional earthing: new guidance for earthing and equipotential bonding for information and communication technology (ICT) equipment. Covers earthing for broadcast, communication and computer networks, distinguishing clearly between functional and protective earthing.
Section 716 Power over ethernet (PoE) and data: clarifying rules for PoE and extra-low voltage (ELV) DC power distribution in smart buildings and data installations.
Chapter 57 energy storage and generation: expect revised requirements for stationary secondary batteries (home battery systems) and low-voltage generators to ensure safe integration.
BS 7671 Amendment 4 also includes updates across a range of other areas, including:
Medical: enhanced electrical safety requirements for healthcare environments.
Inspection and testing: new information on periodic inspection and testing procedures (Chapter 65).
Hybrid systems: revisions for combined renewable and traditional electrical installations, including hybrid setups.
Arc fault detection (AFD): covering AFD devices (AFDDs) on EV charging installations (EVCIs).
Firefighter’s switches: to improve fire safety, firefighter’s switches must be installed in locations identified by the fire engineer as part of a building’s fire strategy (e.g. outdoor lighting).
How will Evolution Electrical react to the changes?
Electrical standards and safety requirements in the UK are constantly evolving. As professional, NICEIC-registered electricians, Evolution Electrical will stay fully informed on the latest developments with BS 7671 Amendment 4 and, where necessary, will update our own procedures and risk assessments.
Our fully-qualified team undertakes regular training, refresher courses and manufacturer-led certifications to ensure all work meets current legislation and best practice. We also closely follow guidance from recognised industry bodies, ensuring every installation, inspection and upgrade is fully compliant and completed to the highest safety standards.
This commitment to continual learning and compliance is what makes Evolution Electrical a trusted choice for homeowners and businesses alike across Hertfordshire and Bedfordshire. Whether you live in Shefford or St Albans, our team is committed to delivering honest advice alongside high-quality workmanship.
By combining technical expertise with personal service, we build long-term relationships with our clients so they can be confident their electrical systems are safe and reliable. To learn more, get in touch today.
