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.
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.
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.
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.
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.
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.
Understanding the labour vs materials split
Materials — consumer units, cabling, sockets, fittings — are usually a smaller share of an electrical quote than labour, particularly for jobs involving lifting floors or chasing walls. If a quote seems unusually cheap, check whether it's using a lower-spec consumer unit or cabling than a competing quote, not just a lower labour rate.
Outdoor and garden electrics
Outdoor sockets, garden lighting, and supplies to sheds or outbuildings need weatherproof (IP-rated) fittings and their own RCD protection — standard indoor sockets and cabling aren't rated for outdoor use. This is notifiable work under Part P if it involves a new circuit.