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.
Tripping fuses or flickering lights? Common causes
A breaker that trips repeatedly usually means a fault on a specific circuit, not the consumer unit itself — an electrician can isolate which circuit is affected. Flickering lights are often a loose connection rather than a faulty bulb, and worth having checked rather than ignored, particularly in older wiring.
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.
Electrics in bathrooms — zone rules explained
UK wiring regulations split a bathroom into zones (0, 1, 2, and outside zones) based on distance from water, and each zone restricts what can be fitted and to what IP (ingress protection) rating. A standard socket can't go in zone 1, for example. This is why bathroom electrical work is notifiable under Part P — it's assessed against these zones, not just wired like any other room.
LED lighting and energy-saving rewires
Swapping halogen downlights for LEDs is usually straightforward, but older dimmer switches often aren't compatible with LED drivers and need replacing alongside the bulbs, or you'll get flickering or a limited dimming range. If you're rewiring a room anyway, it's worth speccing LED-compatible circuits from the start rather than fixing dimmer compatibility later.
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.
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.
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.