Updated: May 2026
If your fuse box is old, frequently tripping or no longer suitable for modern electrical demands, you may be considering a consumer unit replacement.
One of the first questions most homeowners ask is: “How much does it actually cost?”
The answer depends on several factors, including the size of the property, the number of circuits and the condition of the existing electrical installation.
At LA Electrical & Solar, we regularly carry out consumer unit replacements across Bristol and South Gloucestershire, upgrading older fuse boards to modern systems designed to improve electrical safety and reliability.
Typical Consumer Unit Replacement Costs
As a rough guide, most consumer unit replacements in the Bristol area cost around £950–£1,500+ including VAT, testing, and certification. A metal consumer unit with full RCBO protection, surge protection, and all the associated certification will typically sit toward the higher end of that range. Properties that need additional remedial work done at the same time will cost more.
What Affects The Cost?
Several factors influence the final cost of replacing a consumer unit.
Number Of Circuits
Larger homes typically have more lighting circuits, socket circuits, showers, cookers, outdoor supplies, and garage or garden office circuits. More circuits require a larger consumer unit and more testing time, which affects the overall price.
RCBO Vs Dual RCD Consumer Units
Modern consumer units can be configured in different ways.
Dual RCD Boards
Generally cheaper initially, but multiple circuits may lose power if a fault occurs.
RCBO Boards
Provide individual protection per circuit and are generally considered the better option for fault finding, reliability and convenience.
Most of the systems we install now use RCBO protection.
Surge Protection Devices (SPD)
Surge protection is now commonly installed in modern consumer units to guard against voltage spikes and transient overvoltages. It protects TVs, computers, appliances, smart home equipment, and solar or EV charging systems from damage caused by sudden surges on the supply.
Additional Electrical Work
Sometimes additional work is needed before a new consumer unit can safely be installed. This might include earthing or bonding upgrades, circuit repairs, identifying existing faults, or replacing damaged accessories. A modern consumer unit can reveal issues that an older fuse board was simply passing over.
Why Cheap Consumer Unit Replacements Can Be Risky
A consumer unit replacement isn’t a box swap. The work should include a proper inspection of the installation, testing of all circuits, verification of safety, and certification to current regulations. Very cheap quotes sometimes don’t include full testing, fault investigation, surge protection, RCBO protection, or certification. The quality of the installation and testing is just as important as the unit itself.
How Long Does A Consumer Unit Replacement Take?
Most consumer unit replacements are completed within a day. Power will normally need to be switched off while the work is carried out safely and circuits are tested. We always aim to minimise disruption and keep customers informed throughout the installation.
When Should A Consumer Unit Be Replaced?
You may want to consider an upgrade if your fuse board is over 20–30 years old, still has rewireable fuses, has no RCD protection, trips regularly, or you’re planning to add solar panels or an EV charger. A damaged or overheating consumer unit should be looked at as a priority regardless of age.
Will I Need A Full Rewire?
Not necessarily. In many cases, a consumer unit can be replaced without requiring a full rewire, provided the existing wiring is still in a safe condition. However, electrical testing may identify issues that require remedial work before a new consumer unit can be installed safely.
Will I Receive Certification?
Yes. A properly installed consumer unit replacement includes electrical testing, an Electrical Installation Certificate, and Building Regulations notification. As NICEIC-approved electricians, we provide the appropriate certification on completion of the work.
Frequently Asked Questions
<!– wp:yoast/faq-block {"questions":[{"id":"faq-question-1778507866217","question":["Is replacing a consumer unit messy?"],"answer":["Usually not. Most installations are completed with minimal disruption, although power will need to be temporarily isolated."],"jsonQuestion":"Is replacing a consumer unit messy?","jsonAnswer":"Usually not. Most installations are completed with minimal disruption, although power will need to be temporarily isolated."},{"id":"faq-question-1778507871943","question":["Can I replace a consumer unit myself?"],"answer":["Consumer unit replacement is not considered DIY work and must comply with Part P Building Regulations."],"jsonQuestion":"Can I replace a consumer unit myself?","jsonAnswer":"Consumer unit replacement is not considered DIY work and must comply with Part P Building Regulations."},{"id":"faq-question-1778507879759","question":["Do plastic consumer units need replacing?"],"answer":["Not always, but older plastic boards may not meet current standards and may offer lower fire resistance than modern metal consumer units."],"jsonQuestion":"Do plastic consumer units need replacing?","jsonAnswer":"Not always, but older plastic boards may not meet current standards and may offer lower fire resistance than modern metal consumer units."},{"id":"faq-question-1778507923206","question":["Can a new consumer unit stop circuits tripping?"],"answer":["If the tripping is caused by an outdated or faulty consumer unit, yes. However, modern boards can also reveal existing faults elsewhere on the installation."],"jsonQuestion":"Can a new consumer unit stop circuits tripping?","jsonAnswer":"If the tripping is caused by an outdated or faulty consumer unit, yes. However, modern boards can also reveal existing faults elsewhere on the installation."},{"id":"faq-question-1778507933371","question":["How do I know if my fuse box is outdated?"],"answer":["Signs include rewireable fuses, no RCD protection, frequent tripping, visible damage, or buzzing and overheating."],"jsonQuestion":"How do I know if my fuse box is outdated?","jsonAnswer":"Signs include rewireable fuses, no RCD protection, frequent tripping, visible damage, or buzzing and overheating."}]} –>Usually not. Most installations are completed with minimal disruption, although power will need to be temporarily isolated.
Consumer unit replacement is not considered DIY work and must comply with Part P Building Regulations.
Not always, but older plastic boards may not meet current standards and may offer lower fire resistance than modern metal consumer units.
If the tripping is caused by an outdated or faulty consumer unit, yes. However, modern boards can also reveal existing faults elsewhere on the installation.
Signs include rewireable fuses, no RCD protection, frequent tripping, visible damage, or buzzing and overheating.
Consumer Unit Replacements In Bristol
At LA Electrical & Solar, we carry out consumer unit replacements across Bristol, Thornbury, Bradley Stoke, Westbury-on-Trym and the surrounding areas. We focus on high-quality installations, clear advice and doing things properly — with no compromise on safety or workmanship.
