Part P explained: what UK homeowners legally can't DIY on their own wiring

Part P of the Building Regulations (England and Wales) is the electrical-safety rule most UK homeowners have heard of and few understand. The confusion is binary: some believe all home electrics must be done by an electrician (false), others believe none of it is regulated (dangerously false). Part P actually splits the work into two lists — notifiable and non-notifiable — and the split follows risk: rooms with water, the great outdoors, and anything involving new circuits or the fuse board.

What you can legally do yourself

Three groups sit on the DIY side. Like-for-like replacement anywhere — swapping a damaged socket, switch or light fitting for the same kind, in any room including a kitchen or bathroom. Additions to existing circuits outside special locations — adding a socket or spur to an existing ring in a living room or bedroom, wiring a new ceiling light from an existing lighting point. Minor maintenance and repair anywhere. The catch that makes it honest: even non-notifiable work must still meet BS 7671, the wiring standard — correct cable, correct connections, RCD protection as required. "Legal to do" and "done competently" are two different bars, and the first doesn't excuse missing the second.

What's notifiable — the other list

All new circuits, anywhere, for any purpose. Consumer unit replacement or upgrade — the board is the safety brain of the house. Any addition or alteration to existing circuits in "special locations" — rooms containing a bath or shower, and by the same logic of the schedules, kitchens: adding a socket, moving a light, wiring an electric shower or hob in a kitchen or bathroom is notifiable, the only exceptions being like-for-like swaps. Everything outdoors — garden lighting from new wiring, power to sheds, garages and outbuildings, EV chargers, pond pumps. The routes to compliance: a registered electrician (NICEIC, NAPIT and similar government-approved schemes) self-certifies and notifies the council for you — usually the cheapest and simplest path; or you DIY with building control approval — apply before starting, pay the inspection fee (commonly a few hundred pounds), have the work inspected at first and second fix, and provide test results to BS 7671. If that sounds like a lot, it is: it's the price of doing electrician work without being one.

What happens if you ignore it

Non-compliant notifiable work is a building-regulations breach — enforceable as a criminal matter, with powers to require work to be opened up, altered or removed, at the owner's cost. And the quieter penalty is the one that arrives at sale time: no certificate, no paperwork, buyer's solicitor asking questions — the regularisation-and-indemnity dance, in its most awkward variant, because uncertified electrics are the first thing every surveyor and lender probes.

The honest safety framing

The legal map above is the floor. The cables-behind-the-wall guide and the overloading piece cover the physical dangers, and the warning-signs guide covers what failing electrics smell, look and sound like. Our desk's standing rule holds whether or not law requires it: everything past like-for-like swapping belongs to a registered electrician, and everything near the consumer unit belongs there always — the same line the induction guide draws. Scotland and Northern Ireland run different arrangements (Scotland via building standards, NI via its own regulations) — check locally before any notifiable-scale project.

Sources: The Building Regulations 2010, Approved Document P (electrical safety) and its notification schedules; BS 7671 as the technical standard; government-approved competent-person scheme guidance. Reviewed September 2026 · general information, not legal advice.