An EV charger needs its own circuit and protective devices. If the consumer unit has no spare way, or the existing devices are of a type that cannot sit alongside the charger protection the design needs, the installer has two honest options: a new consumer unit, or a small additional enclosure fed correctly from the supply. Stuffing the circuit into a lighting MCB is not an option.
Spare ways on a consumer unit for an EV charger
Boards from the 1990s and early 2000s are a frequent reason a 'simple' quote grows. Metal consumer units, RCD type and space for surge protection all come into that conversation. A photo of the existing board with the cover open, taken safely, tells a good installer a lot.
- A dedicated way is required
- No spare way means board work
- A small EV enclosure can be enough
- RCD type is part of the choice
Spare ways on a consumer unit for an EV charger: questions for the first visit
Count visible spare slots if you can, but do not remove covers if you are unsure. Note whether the board is in a cupboard, under stairs, or outside. Access changes labour.
How spare ways on a consumer unit for an EV charger moves the job
A consumer unit change is a significant part of the bill and should be a line of its own, with the make and whether RCDs or RCBOs are included. A small additional EV board can be cheaper when the rest of the house board is otherwise sound. The installer should say why they chose one.
What goes wrong with spare ways on a consumer unit for an EV charger
The mistake is accepting 'we'll find a way on the day' or buying a charger first and discovering the board is the real project. Another mistake is replacing a board that only needed one extra enclosure.
Point at spare ways on a consumer unit for an EV charger in the pack
Get the board scope, the device types and the certificate type on the quote. Ask what happens if the survey finds a different board from the photo.
Frequently asked questions
Can you use the shower circuit?
No. The charger needs its own correctly protected circuit. Sharing with a shower is not a compliant design.
Does a new board need building control?
Notifiable electrical work is certified through the competent-person scheme or building control. Your installer should say which route they use.
Will the power be off all day?
Often for part of the day if the board is changed. Ask so you can plan freezers and home working.
Are RCBOs better?
They often make fault-finding easier because one circuit trips alone. They can cost more. Ask for the reason on your board, not a slogan.
Core buying guides
Start with these high-intent guides, then dig into the rest of the library.
Related guides
Sources and further reading
How this guide was prepared
This guide was written by the Local EV Installers Editorial Team. We compare official guidance, legislation and established consumer information, separate general information from project-specific advice, and show publication dates and sources. We do not accept installer accreditation claims at face value.