Do You Need a New Consumer Unit?A Homeowner's Guide

Your consumer unit — often called the fuse board or fuse box — is the nerve centre of your home's electrical system. It controls and protects every circuit in the property. If yours is old, outdated, or showing signs of wear, it may be putting your home at risk without you even knowing it.

What Is a Consumer Unit and What Does It Do?

The consumer unit is a metal or plastic enclosure, usually mounted near your electricity meter, that contains the main switch, circuit breakers, and RCDs (residual current devices). Its job is to distribute electricity around the property and — critically — to cut the power automatically if something goes wrong on a circuit.

Modern consumer units use miniature circuit breakers (MCBs) and RCDs to do this. Older units used rewirable fuses or early cartridge fuses that offer far less protection and cannot respond as quickly or reliably to faults.

Signs Your Consumer Unit May Need Replacing

1. You Have an Older-Style Fuse Board with Rewirable Fuses

If you can see ceramic or porcelain fuse holders with wire running through them, your board is likely from the 1970s or earlier. These offer no RCD protection and cannot disconnect fast enough to prevent electric shock or fire. Replacing them is a significant safety improvement.

2. The Unit Has No RCD Protection

RCDs (residual current devices) are designed to detect small imbalances in electrical current — the kind that occur when current is passing through a person — and disconnect the circuit within milliseconds. Current UK regulations require RCD protection for most circuits. If your board has none, it does not meet modern safety standards.

3. Circuit Breakers Trip Frequently

An occasional trip is normal. Frequent tripping — especially on the same circuit — may indicate the board is struggling with the current electrical load in your home, or that a breaker is faulty. Modern homes use significantly more electrical appliances than boards installed 20–30 years ago were designed to handle.

4. The Board Feels Warm or Shows Signs of Burning

A consumer unit should be cool to the touch. Warmth, scorching, or a burning smell around the board is a serious warning sign and should be investigated by a qualified electrician immediately. Do not ignore this.

5. You're Planning an Extension, EV Charger, or Major Appliance

Adding an EV charging point, a home extension, or any significant new circuit often requires the existing board to be assessed for capacity. Many older boards simply cannot accommodate additional circuits safely without an upgrade first.

6. Your Board Has Fewer Than 6 Ways

Older boards with limited circuit capacity were designed for homes with far fewer electrical circuits than we rely on today. A modern home typically needs separate circuits for the cooker, shower, sockets, lighting, boiler, outdoor sockets, and more. If your board is running out of space, an upgrade gives you headroom.

7. Your EICR Has Flagged It

If a recent Electrical Installation Condition Report (EICR) has returned a C1 or C2 code relating to your consumer unit, remedial work is required. An EICR is the most reliable way to understand the current state of your board and the wider installation.

What Does a Consumer Unit Upgrade Involve?

A consumer unit upgrade typically takes half a day to a full day, depending on the size of your property and the number of circuits involved. Here's what you can expect:

• The existing board is disconnected and removed.
• A new board — usually a dual RCD or fully protected RCBO board — is fitted in the same location or nearby.
• All existing circuits are connected to the new board and tested.
• An Electrical Installation Certificate (EIC) is issued on completion, confirming the work meets BS 7671 wiring regulations.

The work requires the electricity supply to be switched off for the duration, so it's worth planning around this. We always aim to minimise disruption and work efficiently so your power is restored as quickly as possible.

Do I Need Building Regulations Approval?

Yes. Consumer unit replacement is notifiable work under Part P of the Building Regulations in England. This means it must be carried out by a registered competent person — such as a NICEIC Domestic Installer like Upton's — who can self-certify the work. Using an unregistered electrician means the work must be separately inspected and certified by Building Control, which adds cost and delay.

How Much Does a Consumer Unit Upgrade Cost?

Costs vary depending on the size of the board, the number of circuits, and any additional work required such as upgrading the earthing arrangement. As a general guide, most straightforward domestic upgrades fall in the range of £400 - £700 fully installed and certified. We provide a clear, written quote before any work begins.