Consumer unit and fuse board upgrades

Age on its own isn't a reason. What matters is whether the board still provides the protection the installation needs, and whether it's in good enough condition to keep doing it.

• Rewireable fuses, the ceramic carriers with fuse wire in them. No RCD protection at all, and no way of adding it.
• A plastic board in a communal area or under a wooden staircase, current regulations call for a non-combustible enclosure in those positions.
• No RCD protection on socket circuits or on cables buried in walls.
• One RCD covering the whole house, so a fault in the garden lights kills the freezer.
• Signs of heat: browning around terminals, a smell of hot bakelite, a board that's warm to the touch.
• No spare ways, when you need a new circuit for a charger, shower or outbuilding.

The practical difference is that faults get isolated instead of taking the house down.

• RCBOs. Each circuit gets its own overload and earth-fault protection, so a fault on one circuit leaves the rest alone.
• A steel enclosure, which is what the regulations require in a domestic installation.
• Surge protection (SPD), which is worth having if you've got anything expensive plugged in, boiler controls, heat pumps, solar inverters, home networking.
• Clear, permanent labelling, so the next person to open it, including you at midnight, can see what's what.
• Spare ways, so the next addition doesn't mean starting again.

The board swap itself is quick. The testing either side of it is what takes the time, and it's not optional. You can't certificate a board on an installation you haven't proved.

1. Tests before we start, so any pre-existing faults are found before the old board comes off rather than after.
2. Power off, old board out, new enclosure fitted and every circuit re-terminated and identified.
3. Full testing: continuity, insulation resistance, loop impedance, RCD/RCBO operation on every way.
4. Labelling, an Electrical Installation Certificate, and notification of the work under the Building Regulations.

Expect to be off supply for a chunk of the day. If you work from home or have someone who needs power, say so when you book and we'll plan around it.

It sometimes does, old borrowed neutrals, a nail through a cable, damp in an outside light, a circuit with poor insulation resistance. New RCBOs are far more sensitive than an old rewireable fuse, so faults that the old board tolerated will show up.

You'll be told what's been found, what it means, and what it costs to put right before any extra work happens. Nobody likes a surprise on the invoice.