Fuse Board Replacement: A Beginner's Guide

The fuse board is a crucial part of an electrical system. Not only does it distribute electricity throughout the property, but it also incorporates safety features which can prevent electrical shocks and fires.

So, it’s important the fuse board works reliably and that it is changed periodically. In this article, we look at the basics of fuse board replacement, including the signs you’re due an upgrade.

What is a fuse board?

The first thing to clarify is that the fuse board is the same as the fuse box. This is a box located somewhere inside the property – often in a cupboard or on a wall. The box holds various accessible switches or fuses which control the electric supply to different rooms or parts of the property, such as the lighting.

If you experience an unexpected loss of power, your first port of call is usually the fuse board to check if one of the switches or fuses has tripped.

The terms “fuse board” and “fuse box” are increasingly being replaced with “consumer unit” to reflect the latest features.

The main difference is that traditional boxes or boards have fuses with wires inside, while consumer units have circuit breakers built in. Modern consumer units have also been developed to handle the higher electricity demand households now have, due to multiple devices being used at the same time.

When you’re ready for a fuse board replacement, you will have a consumer unit installed.

How often should a fuse board be replaced?

Fuse boards have a lifespan, after which they should be replaced. This varies but 15 years is a good guide. In comparison, a consumer unit will last up to 30 years before it needs to be replaced.

There is no legal requirement to change a fuse board for a consumer unit. However, as well as reduced function, older fuse boards won’t have the latest safety features.

Signs a fuse board replacement is due

Even if your fuse board is not at the end of its lifespan, there are signs that it is not working as well as it should and may need to be changed.

These include flickering lights or if the fuse board is regularly tripping. A more practical reason is if additional capacity is required, such as following a house extension. Further reasons include if an upgrade is required to obtain an Electrical Installation Condition Report for a rental property or to satisfy the demands of an insurer.

We offer a free guide which sets out 9 indicators your fuse board needs replacing. Head to our homepage to download your copy (email address required).

What are the main features of a fuse board?

As fuse boards are now being replaced with consumer units, we will run through the features of the latest technology.

Main switch – This is simply the main control switch which shuts off power at the source. If you ever need to turn the electricity off at the mains, this is the switch to flip.

Miniature circuit breakers (MCB) – These small circuit breakers cut off the electricity supply if the system gets overloaded for any reason. MCBs replace the individual fuses in a traditional fuse board.

Residual current devices (RCD) – This important feature helps to prevent electric shocks by cutting off the power supply if an imbalance is detected. RCDs are more sensitive than traditional fuses.

Surge protection – Another safety feature, this protects against electricity surges, which can lead to damage to electrical equipment and devices. Again, this is an upgrade on the protections offered by traditional fuse boards.

Residual current circuit breaker with overload (RCBO) – Some models of consumer unit incorporate a miniature circuit breaker and an RCD. This enhances safety by shutting off the electricity supply if the RCBO detects an earth fault, short circuit or overload.

What does a fuse board replacement entail?

If you’re due a replacement or simply want to upgrade to take advantage of the modern features of a consumer unit, here are the stages of the work:

• Assessment – A professional electrician will assess the current fuse board and offer advice on a suitable replacement, taking the householder’s current needs into account.
• Preparation – Once the earthing and bonding have been checked, the installation starts with shutting off the power at the mains to ensure the work is carried out safely.
• Disconnection – The existing fuse board is removed by unscrewing the box and taking out the individual fuses.
• Connection – Once the fuse board has been removed, the new consumer unit is attached by screwing it to the wall in the desired location and connecting the individual circuits.
• Testing – Before the work is signed off, testing will take place using a voltmeter to ensure everything is working correctly.

Overall, the work can take between two and five hours to complete.

How much does the work cost?

The cost of a fuse board replacement will depend on factors including whether the box is being installed in a different location to the current one and how much capacity is required. It will also depend on the type of consumer unit chosen and the labour costs.

As a guide, fuse box replacement is around £500 (including materials and labour). However, it’s important to seek expert advice to get an accurate quote for your property.

Can a non-professional carry out the work?

This is not work for an amateur to attempt. Risks include causing damage and injury and leaving the electric system in an unsafe state.

Consumer units can be bought separately from reputable suppliers – but it’s important they are installed by a qualified electrician who has experience in undertaking this type of work.

As well as the practical and safety aspects, a professional electrician must sign off the work and issue a certificate which confirms compliance with the relevant building regulations.

Don’t take risks with your fuse board replacement – call in the experts

Based in Hammersmith, SparkPro Electrical has 15 years’ experience in all kinds of domestic electrical services, including fuse board replacement. NAPIT accredited and TrustMark approved, we offer customers across West London full peace of mind that all work will be completed to the highest standards.

Contact us today to find out more about our electrical services or for a free, no-obligation quote.