Red flags in a cheap electrical quote
A quote significantly below the others is worth asking about before accepting — check it includes a proper consumer unit (not a budget one that doesn't meet current standards), covers making good afterwards, and includes the certificate you're entitled to for notifiable work. Cash-only, no fixed address, and no registration number are all worth asking about directly.
What affects the cost
Cost depends on the scope of the job, how much of the property needs to be accessed, the age and condition of the existing wiring, and whether the consumer unit needs upgrading. A single socket replacement is quick and low-cost; a full rewire in an older property takes longer, partly because of the making-good work afterwards.
Lighting design and circuit planning
Adding recessed downlights, under-cabinet lighting or dimmer circuits usually means new cabling even if you're keeping the existing consumer unit, since older lighting circuits weren't sized for LED transformers or multiple dimmer switches. Plan lighting changes before, not after, a room's redecorated.
New build and extension electrical work
Wiring an extension or new build from scratch is different from rewiring an existing room — it's planned around final wall positions and fittings before plastering, so timing with your builder matters. First-fix electrical work (cabling inside walls) has to happen before plastering; second-fix (sockets, switches, fittings) after.
Common electrical myths, busted
"If it's not broken, the wiring's fine" — wiring can be dangerous long before it visibly fails. "Any handyman can do electrics if it's small" — scope, not size, determines whether work is notifiable. "A tripped RCD means the RCD is faulty" — usually it means something else on that circuit is, and the RCD is working as intended.
Solar panels and battery storage wiring
Solar PV and battery storage installation is specialist work, usually done by an MCS-certified installer rather than a general electrician, and needs its own isolation switches and a compliant connection to your consumer unit. Your energy supplier and network operator also need to be notified before or after installation, depending on system size.
What does an RCD do?
A residual current device cuts power within milliseconds if it detects current leaking to earth — the main protection against electric shock from a faulty appliance or damaged cable. Modern consumer units have RCD protection built in across multiple circuits (RCBOs); older ones may only protect part of the property.
DIY electrical work vs when you need a professional
Under Part P of the Building Regulations, certain electrical work in a home is notifiable — it has to be carried out by a registered electrician who can self-certify it, or separately inspected by your council's building control. New circuits, consumer unit replacements, and any new work in a kitchen or bathroom are notifiable. Like-for-like socket or switch swaps usually aren't.