Consumer units in domestic premises are now specified with non-combustible enclosures, which in practice means steel. If your property has an older plastic unit, that alone is not an emergency — but it is a useful prompt to look at what else the board does and does not provide.
What changed and why
Loose terminations inside plastic enclosures were implicated in fires where the enclosure itself contributed to spread. A steel enclosure contains that. It is a containment measure, not a claim that plastic boards fail more often.
What else usually comes with a change
In practice, replacing an older board brings several improvements at once, which is why we quote the whole package rather than the enclosure alone.
- Earth leakage protection on circuits that had none
- Per-circuit RCBOs if specified
- Optional surge protection
- Clear circuit labelling and an up-to-date schedule
- Bonding checked and upgraded where required
Do you have to replace it?
No. A sound plastic board with functioning protection is commonly a C3 observation — improvement recommended. A rewireable fuse box with no RCD protection is a different conversation, and we would explain why rather than simply quoting.
Common questions
- Is my plastic board illegal?
- No. Standards apply at the time of installation; existing installations are assessed on condition.
- Will an insurer object?
- We are not aware of a general requirement, but a current EICR is the document that answers such questions.
- Can the board be moved?
- Yes, though relocating adds cable work and cost. We will price both positions.
- How long does replacement take?
- Typically a working day, with the supply off for much of it.
Send a photo of the board and we will tell you what it is and what a change would actually gain you.
Related guides
- RCD vs RCBO: What the Difference Means at HomeThe difference is not protection quality — it is how much of your house goes dark when something leaks.
- Surge Protection Devices in a Domestic BoardAn SPD protects connected equipment from transient voltage spikes — not from every electrical mishap.
- What Affects the Cost of a Consumer Unit UpgradeTwo identical-looking boards can be very different jobs once the cover comes off.