Consumer unit replacement in Harrow

Signs your consumer unit is due

• It still has rewireable fuses, with fuse wire in the carriers
• There are no RCDs, or only some circuits have them
• It is mounted on a wooden board, or the plastic casing is cracked or discoloured
• Breakers trip with no obvious cause
• An EICR has coded it C2
• There is no spare way for a new circuit such as a shower, an EV charger or a garden office

Why new boards are metal

Since 1 January 2016, a consumer unit fitted in a home, new or as a replacement, must have a non-combustible enclosure, which in practice means steel. The IET is clear that existing plastic units do not all have to be replaced because of this. An inspector judges an existing unit on its age, condition and where it is fitted, and a plastic board in good condition can stay. If yours sits under a wooden staircase or in a timber cupboard, the IET suggests improving ventilation and fitting a smoke alarm nearby.

Notifiable work and your certificates

Replacing a consumer unit is notifiable under Part P of the Building Regulations in England. The work has to be registered with building control, either by an electrician registered with a competent person scheme or through the council. You receive an Electrical Installation Certificate for the work and, afterwards, a building regulations compliance certificate. Keep both: buyers’ solicitors ask for them when you sell.

We are registered with NICEIC as a Domestic Installer, a competent person scheme, so we notify the work to building control ourselves and you do not need to apply to the council.

Why every circuit is tested before the change

A new board has RCDs that switch off if a circuit leaks current to earth. An old circuit with a hidden fault, a damp outside light or a nail through a cable, can run happily on an old fuse box and then trip the new RCD the moment it is connected. Testing each circuit before the swap finds these faults first, so they can be priced and fixed as part of the job rather than discovered at the end of the day with the power off.

What affects the price

The number of circuits, any faults found in testing, and whether the board needs to move all change the price, as does adding surge protection or AFDDs. Sometimes the main earth or the meter tails need upgrading too; some of that falls to the network operator rather than us, and we tell you if it does. In an HMO, AFDDs are required on socket circuits, so they are included.