The consumer unit is the heart of your electrical installation. It decides how quickly power is cut when something goes wrong, and on far too many London properties, it is still a plastic box of rewireable fuses installed when Concorde was flying.
Signs yours needs replacing
- Rewireable fuse wire or old cartridge fuses instead of breakers
- A wooden back-board or a plastic enclosure (metal has been required since 2016 in domestic premises)
- No RCD protection, no test button anywhere on the board
- Nuisance tripping that takes out half the house at once
- Signs of heat: browning, a fishy smell, or a warm cover
- An EICR with C2 codes relating to the board or lack of RCD protection
What an upgrade actually gives you
RCD protection against electric shock
A residual current device detects tiny imbalances, current leaking to earth through a person or a damaged cable, and disconnects in under 40 milliseconds. Fuse wire cannot do this. It is the difference between a nasty shock and a fatal one.
Individual RCBOs, not shared banks
Cheaper upgrades use two shared RCDs, so a fault on the kitchen kills half the house, including the freezer and the router. We fit individual RCBOs as standard: a fault on one circuit takes out that circuit alone. It costs a little more and it is worth every penny.
SPD and AFDD options
A surge protection device shields sensitive electronics, heat pumps, EV chargers, home offices, from transient overvoltage. Arc fault detection devices spot the arcing that causes electrical fires. Both are now recommended in the 18th Edition and we will tell you honestly whether your property warrants them.
What upgrade day looks like
- 1Pre-works testing: we test the existing installation first, because a new board on faulty circuits will simply trip.
- 2Isolation and removal of the old board, with the supply made safe.
- 3Installation of the new metal 18th Edition unit, circuits identified, labelled and terminated to torque settings.
- 4Main protective bonding to gas and water upgraded to 10mm² where required.
- 5Full dead and live testing of every circuit, RCD trip times recorded.
- 6Power restored, board labelled, area cleaned, and your Electrical Installation Certificate issued.
- 7Building Control notification through our competent person scheme, this is notifiable work.
“We recently had our fuseboard upgraded and the whole experience was excellent from start to finish. The installation was neat, tidy, and completed efficiently with minimal disruption.”
Cost and time
Most London properties are done in one working day, typically between six and eight hours. Expect £550–£900 for a standard domestic RCBO board including testing and certification; larger properties, three-phase supplies, or boards needing a new tails-and-henley arrangement will cost more.
Want an honest opinion on whether yours needs doing? Send a photo of your board to 07938 382020 and we will tell you straight.
Need this doing?
Free advice, then a fixed price
Call and describe what's happening, or send a photo. We cover all London, mon–sat 8am–8pm · emergency call-outs 24/7.
