Consumer Unit UpgradeModern Protection for Your Home
Your fuse box is your home's first line of defence against electrical fire and shock. If you have an outdated unit with rewirable fuses, upgrading to modern RCD protection could save lives.
What Is a Consumer Unit?
Your consumer unit (commonly called a fuse box or fuseboard) is the central distribution point for your home's electrical supply. It divides incoming power into individual circuits and provides protection against overload and earth faults.
Modern consumer units include:
- MCBs (Miniature Circuit Breakers): Protect individual circuits against overload and short circuits. Unlike old fuses, they can be simply reset — no fuse wire replacement needed.
- RCDs (Residual Current Devices): Detect earth faults and cut power in milliseconds. This protects against electric shock from damaged appliances, faulty wiring, or accidents.
- Split-load configuration: Circuits divided across multiple RCDs so a fault on one circuit doesn't black out your entire home.
- Metal enclosure: Required by current regulations, metal units contain any fire within the unit rather than allowing it to spread.
Who needs a consumer unit upgrade? Homeowners in Croydon, Bromley, Sutton, and across London with old fuse boxes, particularly those with rewirable fuses, no RCD protection, or units over 20 years old. Also essential when adding new circuits for EV chargers or extensions.
The Danger of Outdated Fuse Boxes
Old fuse boxes with rewirable fuses were standard decades ago, but they lack the life-saving protection that modern units provide. If your home still has one, you and your family are at increased risk.
Problems with old fuse boxes:
- Slow overload response: Rewirable fuses heat up and melt to break the circuit — a slow process that allows wiring to overheat and potentially start fires.
- No earth fault protection: Without RCDs, faults that could deliver lethal shocks go undetected until someone is injured.
- Wrong fuse ratings: Over years, previous occupants may have fitted incorrect fuse wire ratings, eliminating the protection fuses are meant to provide.
- Degraded condition: Old units suffer from corroded connections, loose terminals, and deteriorating components that create their own hazards.
- Insurance implications: Insurers may refuse claims or increase premiums for properties with outdated electrical protection.
The consequences of inaction: Approximately 14,000 UK house fires annually have electrical causes. Many could be prevented by modern protection devices that detect faults before they become fires. A consumer unit upgrade is a modest investment against potentially devastating outcomes.
Our Upgrade Process
From assessment to certification, we handle everything — including Building Control registration required by law.
Assessment
We inspect your current consumer unit, test circuits, and assess your electrical needs to recommend the right upgrade.
Quote
You receive a detailed fixed-price quote covering the unit, installation, any circuit improvements needed, and full certification.
Scheduling
We arrange installation at a convenient time. Most upgrades complete in a single day.
Installation
We replace your old unit with a modern consumer unit featuring RCD protection for all circuits. Existing wiring is connected and tested.
Certification
Full testing, Electrical Installation Certificate, and Building Control registration. Your installation is fully documented and compliant.
Benefits of a Modern Consumer Unit
A consumer unit upgrade isn't just compliance — it's genuine protection for your home, your family, and your peace of mind.
RCD Protection
Modern consumer units include RCDs that detect earth faults and cut power in milliseconds — preventing electric shocks that could otherwise be fatal.
Fire Prevention
Old fuse boxes with rewirable fuses don't respond quickly to overloads. Modern MCBs trip instantly, preventing the overheating that causes electrical fires.
Circuit Capacity
Additional ways for new circuits — EV chargers, home offices, extensions. Your upgraded unit can accommodate future electrical needs.
Insurance Compliance
Many insurers require modern electrical protection. An outdated fuse box can complicate claims or affect coverage terms.
Property Value
A modern consumer unit reassures buyers and surveyors. It's one less concern during property transactions.
Quick Installation
Most consumer unit upgrades complete in 4-6 hours. You'll have power restored the same day with full protection active.
Consumer Unit Options
Standard Domestic Consumer Unit
Suitable for most homes, a standard split-load consumer unit provides RCD protection for all circuits with division into two or more groups. If one RCD trips, you don't lose power to your entire home. Units typically have 6-12 ways for individual circuit MCBs.
High Integrity Consumer Unit
For properties requiring maximum uptime, high integrity configurations provide three separate RCD groups. Critical circuits (like freezers and medical equipment) have independent protection, minimising the chance of nuisance trips affecting essential services.
RCBO Consumer Unit
The premium option: every circuit has its own RCBO (combined RCD/MCB). A fault on any circuit trips only that circuit — no other circuits are affected. Ideal for larger properties or those with sensitive equipment.
Consumer Unit with Surge Protection
Integrated surge protection devices (SPDs) guard against voltage spikes from lightning or grid disturbances. Particularly valuable for properties with expensive electronics or sensitive equipment.
Amendment 3 Compliance
Current regulations (BS 7671:2018+A2:2022) require specific RCD protection configurations. All our installations meet current amendment requirements, ensuring your consumer unit meets the latest safety standards.
Consumer Unit FAQs
Answers to the most common questions about consumer unit upgrades.
Signs Your Consumer Unit Needs Replacing
Your fuse box is the single most important safety device in your home. If any of these apply, it's working against you, not for you.
Plastic consumer units have been linked to flat-fire incidents — the 18th Edition now requires non-combustible (metal) enclosures in domestic installations.
- You still have rewirable fuses with fuse wire — not modern MCBs
- There's no RCD trip switch (or only one covering the whole property)
- The casing is plastic and the board is more than 10 years old
- Circuits are unlabelled or labelled wrongly
- You've added an electric shower, EV charger or extension and it's been wired in 'somehow'
- The board buzzes, gets warm or smells of plastic when loaded
- Your last EICR called out the consumer unit specifically
- You're planning solar PV, battery storage or a heat pump
Consumer Unit Upgrade Pricing
Modern 18th-edition compliant boards with surge protection and full certification.
| Job Type | Typical Price | What's Included |
|---|---|---|
| Consumer unit upgrade — up to 6-way (RCBO + SPD) | £640–£865 | Branded board, every circuit on RCBO, surge protection, full test of existing installation, EIC certificate. |
| Consumer unit upgrade — up to 10-way (RCBO + SPD) | £720–£980 | Each circuit individually protected — no whole-house trip when one circuit faults. |
| Consumer unit upgrade — up to 15-way (RCBO + SPD) | £810–£1,090 | For larger homes or where extra capacity is needed for EV / solar / heat-pump circuits. |
| Consumer unit upgrade — up to 20-way (RCBO + SPD) | £890–£1,210 | Premium install — branded board, full SPD, meter tails replaced where needed. |
| Three-phase distribution board | From £1,400 | For larger homes, workshops or properties with EV / heat-pump three-phase supply. |
| Sub-main board (garage / outbuilding) | £420–£750 | Includes SWA cable run, isolator and full certification. |
Prices shown are typical guide ranges for Greater London and the South East as of 2026. Every job is quoted in writing on a fixed-price basis after a free site assessment — you only pay the figure we agree, with no hidden extras. A consumer unit change requires Building Control notification — included in our price under our NICEIC self-certification scheme.
Worried About Changing Your Consumer Unit?
It's a half-day job that protects you for 25 years. Here's how we de-risk it.
"How long will I be without power?"
Typical changeover is 3–5 hours of total isolation, scheduled for a time that suits you. Fridges and freezers stay cold for that window — we plan it so you're back on by evening.
"What if you find faults in my existing wiring?"
Pre-installation tests are part of the price. If we find issues that prevent us safely energising the new board, we explain them, quote remedials separately, and you choose what to action.
"Aren't all consumer units basically the same?"
No. We fit Hager, Wylex or MK metal boards with proper SPD and individual RCBOs — not the cheapest dual-RCD board on the wholesaler's shelf. The materials list is itemised on your quote.
"Will it be notified to Building Control?"
Yes — under our NICEIC self-certification scheme. You receive an Electrical Installation Certificate plus a Building Control compliance certificate within 30 days.
Replace Your Old Fuse Box Before It Lets You Down
Old plastic fuse boxes are the leading cause of domestic electrical fires. A modern metal consumer unit costs less than a new boiler and protects you for decades.
NICEIC approved · 25+ years' experience · 12-month workmanship guarantee