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.
Powering a garden office or outbuilding
Running power to a garden office or outbuilding usually means an armoured cable buried below the recommended depth, its own small consumer unit, and RCD protection at the supply end. This is notifiable work and typically needs building control sign-off alongside the electrical certification.
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.
Electrics in kitchens — circuits for appliances
A kitchen refit usually means new dedicated circuits for higher-draw appliances (oven, hob, dishwasher) rather than sharing a single ring main, plus RCD protection for anywhere near a sink. If you're changing the kitchen layout, plan socket and circuit positions before the units go in — moving them afterwards means lifting worktops or units again.
Signs your property needs rewiring
Round-pin sockets, fabric or rubber-insulated cabling, a fuse box with a wooden back, or lights that dim when an appliance switches on are all signs the wiring is overdue for replacement. Most UK wiring is rated to last 30 to 40 years before it needs a full rewire.
Garage and workshop power
Running power to a detached garage or workshop means an armoured cable, usually buried, and its own consumer unit or sub-board with RCD protection at the supply end. If you're planning to run power tools or an EV charger from it, size the supply for that from the start — upgrading later usually means digging the cable run up again.
First fix and second fix, explained
On a rewire or new build, "first fix" is running cables through walls and floors before they're closed up; "second fix" is fitting sockets, switches and light fittings once decorating is done. Getting the timing right with other trades on site avoids cables being covered before they're tested.
Single phase vs three phase supply
Most UK homes run on a single-phase electricity supply, which is enough for typical household use. Larger properties, workshops, or homes adding multiple EV chargers or heavy machinery sometimes need a three-phase supply instead — this is arranged with the network operator, not just your electrician, and can take weeks.