Skip to main content Skip to footer 
The consumer unit (the modern term for what older homeowners still call the fuse box) is the central distribution and protection point for the electrical installation in your home. It receives the main supply, distributes electricity to each circuit, and provides the protective devices (MCBs, RCDs, RCBOs) that disconnect the supply if a fault occurs. Older Aberdeen homes often have consumer units that no longer meet current standards. Replacing the consumer unit is one of the most common pieces of electrical remedial work in Aberdeenshire and is the standard route to bringing an older installation up to current Wiring Regulations.
This guide covers when an Aberdeen consumer unit upgrade is needed, what the upgrade involves, what types of unit are available, what it costs, and what to expect on the day.
When does an Aberdeen consumer unit need upgrading?
Several triggers commonly prompt a consumer unit upgrade:
Older unit identified by an EICR
The most common trigger. An Electrical Installation Condition Report finds that the existing consumer unit does not provide the comprehensive RCD protection required by current Wiring Regulations. The C2 codes from the EICR can be cleared in most cases by replacing the consumer unit with a modern unit. For more on EICR findings and how they translate into remedial work, see our companion guide on EICR services in Aberdeen.
Older rewireable fuse board
Some Aberdeen homes still have the original 1960s or 1970s rewireable fuse board with porcelain fuse holders and replaceable wire fuses. These are no longer compliant with current standards and offer no RCD protection. Replacement is the standard route. Aberdeen has a significant stock of pre 1980 granite homes where original fuse boards may still be in service.
Plastic consumer unit (older standard)
Pre 2016 consumer units were typically housed in plastic enclosures. The 18th edition Wiring Regulations introduced fire resistance requirements for consumer unit enclosures, and current units are typically metal clad. Plastic enclosures are not unsafe in themselves but appear as C3 advisory items on EICRs.
Adding new circuits or major load
When you add a major new load (an EV charger, a heat pump, an electric shower upgrade), the existing consumer unit may not have spare capacity for the new circuit, or the existing unit may be too old to safely add to. Replacing the consumer unit at the same time as adding the new load is often the right answer. For background on EV charger installation, see our guide on EV charger installation in Aberdeen.
Selling the property
An older consumer unit may attract attention during conveyancing. Replacing it before sale removes the issue from the buyer’s questions and can speed up the process.
Letting the property
For Scottish private rentals, the EICR is mandatory and an older consumer unit is typically a C2 issue. Replacing the consumer unit is the route to a satisfactory EICR for the start of a new tenancy.
What does a consumer unit upgrade involve?
The work has four main stages:
Stage 1: Survey and design
Faithful Spark surveys the existing installation, counts the circuits, identifies the supply type (single or three phase), checks the available space, and confirms whether any additional work is needed alongside the consumer unit replacement (such as new earthing, additional bonding, or a meter upgrade by SSEN). A written quote follows.
Stage 2: Replacement
On the day, the existing consumer unit is removed and the new unit is fitted. Each circuit is reconnected to the appropriate protective device in the new unit. The work is mostly completed within 4 to 8 hours depending on the circuit count. There is a planned power outage for the duration of the work.
Stage 3: Testing and commissioning
Each circuit is tested individually with the new unit in place: earth continuity, insulation resistance, polarity, earth fault loop impedance, and RCD trip times. The full installation is checked against BS 7671 standards.
Stage 4: Certification
An Electrical Installation Certificate is issued documenting the new installation. Where the upgrade was carried out alongside an EICR, a satisfactory EICR follow up certificate is also issued.
Consumer unit upgrade cost in Aberdeen
Indicative fully installed costs for consumer unit replacement in Aberdeen in 2026:
- Standard 6 to 8 way consumer unit replacement (typical 3 bedroom flat or smaller home): £450 to £600.
- Standard 10 to 12 way consumer unit (typical 3 to 4 bedroom house): £550 to £800.
- Larger 14 to 18 way consumer unit (4 to 5 bedroom house with electric heating, EV charger, outbuildings): £700 to £950.
- Hybrid consumer unit with full RCBO protection on every circuit: approximately £80 to £150 above the standard rate (more protective devices but better selectivity).
- Three phase commercial consumer unit: from £900 by inspection.
The price includes the new consumer unit, all required protective devices (MCBs, RCDs, or RCBOs to suit the circuit count), the labour to remove the old unit and fit the new one, electrical testing, and the Electrical Installation Certificate. The price is fixed at quotation; there are no surprise extras at completion.
What types of consumer unit are available?
Three main configurations are available for residential installations:
Split load consumer unit
The most common type. The circuits are split into two banks, each protected by its own RCD. If a fault on one circuit trips an RCD, only the circuits on that bank lose power. The other bank continues operating. This is the budget friendly option that meets current standards for most homes.
Dual RCD consumer unit
Similar to split load but with two RCDs of equal capacity. Some installers prefer this configuration over split load for better balance between the two banks. The cost is similar to split load.
RCBO consumer unit (full RCBO board)
The premium configuration. Every circuit has its own RCBO (Residual Current Circuit Breaker with Overcurrent protection). A fault on one circuit only trips that single circuit; every other circuit continues operating. The cost is higher but the resulting installation is more resilient and easier to fault find. Recommended for properties where reliability matters (rentals, holiday lets, properties with home offices, EV chargers).
SPD (Surge Protection Device)
Optional add on for any consumer unit. Protects sensitive electronics from voltage surges (typically caused by lightning or grid switching events). Recommended for homes with significant electronics investment (computers, smart home, AV equipment). Adds £80 to £150 to the consumer unit cost.
AFDD (Arc Fault Detection Device)
Now required by the 18th edition Wiring Regulations on certain circuits in certain property types. AFDDs detect arcing faults in cables and disconnect the circuit before the arc can cause a fire. Faithful Spark advises whether AFDDs are required for your specific installation at the survey stage.
Aberdeen specific considerations
Several Aberdeen specific factors can affect a consumer unit upgrade:
Granite property earthing
Older Aberdeen granite properties sometimes have inadequate earthing arrangements that need upgrading at the same time as the consumer unit. Where the existing earth is from a TT (independent earth electrode) arrangement, the new unit will need a 30mA RCD as the main switch rather than a non RCD main switch.
Tenement flat shared installations
Aberdeen’s tenement properties have shared electrical infrastructure including the riser cable from the meter cupboard to each flat. Consumer unit work in a tenement flat does not affect the riser cable but the work needs to be coordinated with the building’s main supply arrangements. SSEN may need to attend if the meter is being upgraded simultaneously.
SSEN meter changes
The supply meter is owned by SSEN, not by the homeowner. If the meter needs to be moved or upgraded as part of the consumer unit project, this requires a separate SSEN appointment which Faithful Spark coordinates.
Listed buildings
Some Aberdeen properties (particularly in the West End and around Old Aberdeen) are listed. Consumer unit upgrades on listed properties typically do not require Listed Building Consent because the work is internal and reversible, but Faithful Spark checks the planning position at survey stage.
What to expect on the day
Typical timeline for a 10 way consumer unit replacement in an Aberdeen 3 bedroom semi detached:
- 09:00: Faithful Spark arrives. Briefly review the property and confirm the working area. Power is left on for the first hour while the new unit is positioned and prepared.
- 09:30: Power is isolated at the main switch. The existing consumer unit is removed.
- 10:30: The new unit is fitted in place. Each circuit cable is identified and connected to the appropriate protective device.
- 13:00: All circuits reconnected. Initial commissioning checks begin.
- 14:30: Full electrical testing on each circuit individually.
- 15:30: System energised. Final checks. Homeowner walkthrough of the new unit.
- 16:00: Electrical Installation Certificate issued. Work complete.
The exact duration depends on the circuit count and any complications. The disruption to the household is typically half a working day. Most homeowners stay at home for the work to provide access and to be present for the handover.
Why Aberdeen homeowners use Faithful Spark for consumer unit upgrades
- NICEIC registered: Every consumer unit upgrade is certified to BS 7671 and registered with our certification body.
- Fixed price quotes: The price is set at survey. No surprises at the end.
- Same day completion: Most residential upgrades are completed in a single working day.
- One contractor for upgrade plus EICR: Where the upgrade is part of an EICR remedial action, the same team handles both, with a satisfactory EICR follow up certificate issued at the end.
- Coordinated with other work: Where the consumer unit upgrade is part of a larger project (EV charger, solar PV, additional circuits), we plan everything as a single visit to minimise disruption.
Frequently asked questions
Will my power be off all day?
The supply is isolated for most of the working day, typically 4 to 6 hours. We schedule the work to start in the morning so the supply is back on by mid afternoon. We can leave a temporary supply for a fridge or freezer where required.
Do I need to do anything before the work?
Clear the area around the existing consumer unit so we have working space. Confirm any concerns about specific circuits with us in advance. We bring the new unit and all required protective devices.
Can the new unit be in a different location?
Sometimes. Moving the consumer unit to a more accessible location adds cost (typically £200 to £600 for a short relocation, more for longer cable runs) but can be worth doing for properties where the existing unit is in a difficult location such as a cupboard under stairs or behind built in furniture.
Is the work covered by a warranty?
The labour is covered by Faithful Spark’s installation workmanship warranty. The consumer unit and protective devices have manufacturer warranties (typically 5 to 10 years depending on the brand). We register the warranty with the manufacturer at completion.
My property has a smart meter. Does that affect the work?
Not generally. The smart meter is upstream of the consumer unit and the work does not require the meter to be removed. We coordinate with SSEN if any meter movement is needed.
Book a consumer unit upgrade survey
Faithful Spark provides NICEIC certified consumer unit upgrades across Aberdeen and Aberdeenshire. Free survey, fixed price quote, and same day completion for most residential installations. We coordinate the upgrade with EICRs, EV charger installation, and any other electrical work to minimise disruption.
Faithful Spark Electricians. NICEIC approved. Local Aberdeen team. Consumer unit upgrades, fuse box replacements, and Electrical Installation Certificates for Aberdeen, Peterhead, Ellon, Fraserburgh and across Aberdeenshire.
