What we are looking at
Three separate questions get answered at the board, and they have different answers.
- Is there physical space for another circuit and its protection?
- Is the board's protection modern enough to add a continuous high-current load to?
- Can the supply into the house carry the charger on top of everything else that runs?
A board can pass the first and fail the third. Space for a breaker does not mean capacity to run one.
The usual finding in older homes
Boards built for a house with far less plugged into it are the common case. Ceramic rewireable fuses, no safety switches on most circuits, and every way already occupied.
Adding an EV charger to that is not something to do around the edges. In practice the board gets upgraded, which also fixes the protection on the rest of the house — the charger just happens to be the thing that finally forces the issue.
This is why we quote the charger after looking at the board, not before. A number given without seeing it is a guess.
Signs you can see yourself
- Ceramic fuses with rewirable fuse wire rather than circuit breakers.
- No safety switches, or one covering everything rather than several.
- A board that is visibly full, with no spare ways.
- Scorching, discolouration or a burnt smell anywhere in the enclosure.
- Circuits that trip when the kettle and the air conditioner run together.
None of these are proof on their own, but any of them makes an upgrade likely.
If the supply is the limit
Where the board is fine but the supply is the constraint, load management is usually the answer — the charger backs off when the house is drawing heavily and returns to full rate when it is not. It commonly avoids a mains upgrade entirely.
Where the mains genuinely need upgrading, that is a larger job involving the network. We will tell you which of those you are looking at before you commit to anything.
Before you order the charger
Find out what your board can take.
Switchboard assessment and EV charger installation across Greater Brisbane, quoted as one job.
