How to Know When Your Fuseboard Needs Upgrading

Your fuseboard, or consumer unit, is the heart of your home's electrical system. It takes the incoming supply from the street and splits it into circuits that run your lights, sockets, cooker, shower, and everything in between. When the board is doing its job well, you never think about it. When it starts to struggle, you get nuisance tripping, dimming lights, and in the worst case, a real fire risk. This guide will walk you through when to upgrade, what a modern install looks like, and what you can expect to pay.

What Is a Fuseboard?

The fuseboard (or consumer unit) is the grey or white box that holds your home's trip switches. Older homes may still have plastic boards with screw-in rewirable fuses. More modern installations use circuit breakers and RCDs — devices that cut power automatically when a fault is detected. Every circuit in the house terminates at this board, which is why upgrading it is one of the most impactful safety jobs you can do.

Signs You Need an Upgrade

You do not need to replace a working board just because it is old, but there are clear signals that an upgrade is worth planning.

• Old plastic board with rewirable fuses: If your board has screw-in ceramic fuses rather than plastic trip switches, it almost certainly predates modern RCD protection and is due an upgrade.
• No RCD protection: RCDs detect tiny earth leakage currents and cut power in milliseconds. Boards without them leave you far more exposed to electric shock.
• Frequent nuisance tripping: Random trips on circuits that used to run happily often point to a failing RCD or an underlying fault that the existing board cannot isolate cleanly.
• Scorch marks, buzzing, or discolouration: Any visible heat damage or unusual noise coming from the board is a reason to call an electrician the same day.
• EICR recommendations: If a recent Electrical Installation Condition Report listed your consumer unit under C1 or C2 codes, an upgrade is the usual fix.
• Home buying, selling, or remortgaging: A modern board makes EICRs easier to pass and adds peace of mind at the point of sale.

What 18th Edition Means

"18th Edition" is shorthand for the current version of the UK wiring regulations (BS 7671). A fuseboard that meets 18th Edition has a metal (not plastic) enclosure, proper surge protection where required, and individual RCBOs or a pair of RCDs protecting every circuit. We install boards that meet these requirements as standard, so you get the full benefit of modern safety standards without needing to think about it.

Cost Guide

Most domestic fuseboard upgrades fall into a fairly narrow price band, but the final figure depends on how much remedial work your existing circuits need.

• Standard upgrade: £750 – £900. Covers the new 18th Edition board, all RCD or RCBO protection, installation, a full set of tests, and the installation certificate.
• Extra circuits: If your property has more than a typical number of circuits (larger houses, outbuildings, EV chargers, etc.), the cost will scale with the board size.
• Remedial work: If existing cables or terminations need attention to safely connect to the new board, we will quote any additional work up front before starting.
• Alternative power: We supply alternative power during the swap at no extra charge so your essentials keep running while the installation is live.

How Long It Takes

A straightforward like-for-like upgrade is usually completed in a single day. If your home has a lot of circuits or extra testing is needed, it may stretch to a day and a half. We give you a clear timeline as part of the quote, so you can plan around the visit and there are no surprises on arrival.

Frequently Asked Questions