When Do You Need a New Consumer Unit?

Your consumer unit — often called a fuse box — is the heart of your home's electrical system. It controls every circuit in the property and is your first line of protection against overloads and faults. Yet many homes in Darlington and across the North East are still running on consumer units that are decades old, and some of those units pose a genuine safety risk.

So how do you know if yours needs replacing? Here are the key signs to look out for.

Signs Your Consumer Unit Needs Replacing

1. It has old-style fuse wire

If your consumer unit uses rewireable fuses rather than modern circuit breakers, it's almost certainly time for an upgrade. Rewireable fuses offer very limited protection and can be a fire hazard if the wrong fuse wire is used. Modern consumer units use RCD-protected circuit breakers that trip automatically and can be reset instantly.

2. There are no RCDs

A Residual Current Device (RCD) monitors the flow of electricity and cuts the circuit within milliseconds if a fault is detected — protecting you from serious electric shock. Current wiring regulations require RCD protection for most circuits. If your board has no RCDs at all, it doesn't meet modern safety standards.

3. Circuits trip frequently

Occasional tripping is normal, but if breakers trip regularly without an obvious cause it usually points to a fault, overloaded circuits or a failing consumer unit. This needs investigating — and in many cases, a new consumer unit will resolve it.

4. The unit looks or smells burnt

Scorch marks, burning smells, or discolouration around the consumer unit are serious warning signs. Switch off at the main switch, don't attempt to investigate yourself, and call a qualified electrician immediately.

5. You're extending or renovating

If you're adding a new kitchen, extension, garage or outbuilding — or installing an EV charger — your existing consumer unit may not have the capacity or the correct protection. An upgrade ensures the new circuits are added properly and safely.

6. The unit is over 25 years old

Older consumer units weren't built to handle the electrical demand of modern homes — multiple TVs, computers, electric showers, heat pumps and EV chargers. Age alone isn't a reason to replace, but a unit that's more than 25 years old is worth having assessed.

What Does a Consumer Unit Upgrade Involve?

A consumer unit upgrade is a straightforward job for a qualified electrician, but it does require the power to be off for a period. Here's what typically happens:

1. The power is isolated at the meter tails.
2. The old consumer unit is removed and the wiring inspected.
3. A new consumer unit with full RCD or RCBO protection is fitted.
4. All circuits are reconnected, labelled and tested.
5. An Electrical Installation Certificate is issued — you'll need this for insurance, selling your home and building control purposes.

The job usually takes between two and four hours depending on the size of the property and the number of circuits.

How Much Does a Consumer Unit Upgrade Cost?

For most homes in Darlington and the surrounding area, a consumer unit upgrade starts from around £350. The final price depends on the size of the property, the number of circuits and whether any additional work is needed. You'll always receive a fixed price before any work starts.

Is It Worth It?

Absolutely. A modern consumer unit improves safety, brings your electrics up to current standards and gives you the capacity to add new circuits in the future. It also adds value when selling — buyers and their solicitors increasingly check for up-to-date electrical certification.

If you're unsure whether your consumer unit is due for an upgrade, get in touch and we'll take a look. We carry out consumer unit upgrades across Darlington, Teesside and the wider North East.