Do I Need to Upgrade
My Consumer Unit?
A practical UK homeowner checklist for deciding whether your consumer unit genuinely needs replacing. Five clear signs, what an EICR result actually means plus how to weigh up the cost against the safety case.
You probably need to upgrade your consumer unit if any of these apply: the board has rewireable fuse wire or no RCD protection. The enclosure is plastic plus more than 15 years old. Your EICR has flagged C1 or C2 codes on the board itself. You can see scorching, corrosion or melted plastic. The board is full plus blocking new circuits for an EV charger, solar PV or kitchen extension. None of these on their own makes a board illegal. All of them point at a board that has reached natural end of life.
Four figures that
frame an upgrade
These figures help homeowners understand where their existing board sits in the lifecycle plus when industry guidance starts to push for replacement.
Typical Lifespan
A modern metal board fitted to BS 7671 normally serves a property for 25 to 30 years before replacement is sensible.
Owner EICR Cycle
Recommended EICR interval for owner-occupied homes. Every 5 years gives you a clear safety position on the existing board.
Metal Mandate
Plastic consumer units stopped being compliant on new installs in January 2016. If your plastic board predates this, replacement is overdue.
Notifiable Work
A consumer unit upgrade is always notifiable. It must be done by a registered electrician then certified.
Why most UK homeowners
actually replace
Almost every consumer unit upgrade we fit lands in one of four categories. Most homeowners trigger their own decision once one of these arrives in their inbox.
EICR Failure
An EICR has come back with C1 or C2 codes against the board. The cheapest path to a fresh pass is normally a new RCBO consumer unit.
Property Sale or New Tenancy
The buyer's surveyor flagged the existing board. The lender wants reassurance. Or a new tenancy is approaching plus the landlord is upgrading proactively.
Adding New Load
The board is full. An EV charger, solar PV, battery storage or a kitchen extension needs more ways than the existing enclosure has free.
Visible Damage
Scorching, melted plastic, corrosion or condensation inside the box. These are signs the existing board is physically failing plus must be replaced.
Five practical signs your board has reached natural end of life
Not every old board needs replacing. Plenty of 1990s plastic boards are still operating safely in well-maintained UK homes. The decision turns on whether the board still meets a reasonable safety baseline plus whether it can support the household's current load. Here is the checklist a registered electrician walks through on a survey.
1. The board is fitted with rewireable fuses
If your board contains fuse wire that you have to replace by hand, the board predates modern protection standards by decades. Rewireable fuses do not detect earth faults, do not provide RCD shock protection plus respond slowly to overload. They were the UK domestic norm before the 1980s plus are now well past natural end of life. Replacement is genuinely overdue regardless of any other factor.
2. There is no RCD protection on most circuits
If you cannot see at least one device on the board with a test button (T), your installation has no residual current protection. RCD protection on most domestic circuits has been required by BS 7671 since 2008. A board with no RCDs will likely fail an EICR plus will fall short of the modern shock protection standard. This is a common finding on plastic MCB-only boards from the 1990s plus early 2000s.
3. The plastic enclosure shows physical damage
Look at the front of your board. Discoloured plastic, melted areas around terminals, scorch marks above MCBs or condensation inside the cover all indicate thermal stress or moisture ingress. The 2016 amendment to BS 7671 introduced the metal enclosure requirement specifically because plastic enclosures had been implicated in real-world fire spread. Visible damage on a plastic board moves replacement from optional to urgent.
4. The EICR has come back with a C1 or C2 code
An EICR (Electrical Installation Condition Report) gives every observed defect a code. C1 means immediate danger. C2 means potentially dangerous. C3 is improvement recommended but not unsafe. If your EICR has C1 or C2 against the consumer unit itself (not just an outgoing circuit) the report has flagged the board as unsafe. The fastest route to an Unsatisfactory becoming Satisfactory is normally a new RCBO consumer unit because remedial work on an old board often costs almost as much as a fresh install.
5. The board is full plus you need more circuits
An EV charger needs its own dedicated 32A circuit. Solar PV plus a battery storage system normally need two circuits between them. A kitchen extension needs at least one new ring final, often a second for the cooker. If your existing board has no spare ways, you cannot add these without either an additional sub-board (which adds clutter) or a full replacement. Most homeowners take the upgrade route because a new RCBO board future-proofs the house for the next 25 years.
Upgrade cost ranges
by board type
Pricing depends on board size, RCBO vs split-load, accessibility plus whether remedial work is needed. These are typical Milton Keynes plus Bedfordshire ranges in 2026.
Consumer Unit Replacement Cost Bands
Prices include parts, labour, EIC certification plus Building Control notification. Remedial work uncovered during testing (faulty cabling, missing bonding) is quoted separately.
Four steps to a
compliant new board
From first call to handover the typical upgrade runs across two weeks. The actual install day takes 4 to 6 hours.
Free Survey
Onsite check of the existing board. We confirm board type, way count, supply earthing arrangement plus any visible defects requiring quote attention.
Written Quote
Itemised quote covering parts, labour, certification plus Building Control notification. No hidden extras for testing or paperwork.
Install Day
4 to 6 hour install. DNO contacted, supply isolated, new metal RCBO board fitted, every circuit terminated to torque spec, full BS 7671 test sequence.
Certification
EIC issued plus Building Control notified through our certification body. Paperwork lands with you within 5 working days of the install.
Four facts to weigh up
before deciding
Old does not always mean unsafe
A well-maintained 20-year-old plastic board can still be electrically safe. It only fails an EICR if a separate defect is present. Age alone is not a fail.
EV charger triggers most upgrades
Roughly half the upgrade quotes we issue come from an EV charger install where the existing board has no spare way capacity or wrong RCD type.
Insurance often quietly assumes a recent EICR
Most home insurance policies do not require an EICR explicitly but a claim involving an electrical fire is harder to settle without one.
Upgrade cost is below most other major works
A full RCBO board upgrade in Milton Keynes typically costs less than a single bathroom refit yet protects the whole installation for 25 years.
Consumer Unit Upgrades in Milton Keynes
C-Lec Electrical fits new metal RCBO consumer units to BS 7671 across Milton Keynes, Bedford plus the surrounding Bedfordshire area. We carry out free surveys plus written quotes with no obligation. EIC plus Building Control notification handled in full.
Upgrade now vs
leave it for now
If your existing board is showing one or more of the five signs above, here is the practical trade-off between acting now plus deferring the decision.
Get ahead of the deadline
- ✓Fresh EICR pass guaranteed on the new board for the next 5 years.
- ✓EV plus solar ready with capacity for whichever upgrades arrive over the next decade.
- ✓Quietly removes a known objection from any future buyer's surveyor or lender.
- ✓Lower lifetime cost because no reactive call-outs after a sudden fault on an old board.
- ✓Insurance position improves on any future electrical-related claim or coverage review.
Wait for a forced trigger
- ✗Forced upgrade timing when an EICR fails plus you need it done quickly to satisfy a tenancy or sale.
- ✗Higher cost under pressure because urgent quotes do not come with the same flexibility on timing.
- ✗Possible buyer price reduction if a survey flags the board during a property sale.
- ●Existing board may continue serving safely if no faults present plus regular checks done.
- ●Sensible if upgrade budget is genuinely not available right now plus the board passes EICR.
For the wider context on consumer unit types, RCDs, AFDDs plus the regulations behind all of this, head back to our full guide to consumer units where every common homeowner question is answered in one place.
Back to the Consumer Units Guide
This article sits inside our complete Consumer Units knowledge base. The hub covers everything from board types plus RCBOs through to landlord requirements plus BS 7671 wiring regulations.
More on consumer
unit decisions
If you are still nailing down what a consumer unit actually does, the explainer on what is a consumer unit covers every part of the box in plain English. To work out the cost picture before getting onsite quotes, our pricing breakdown for how much to change a consumer unit sets out current 2026 ranges. If you are weighing this up against a property sale specifically, our guide on selling a house with an old consumer unit covers the survey plus mortgage angles. If you are ready to book a survey in Milton Keynes or Bedford, our consumer unit upgrades service page is the fastest route to a quote.