A house usually needs rewiring when its wiring is more than 25 to 30 years old, has rubber or fabric insulation, or an EICR identifies dangerous defects. A full rewire of a three-bedroom house typically costs £4,500 to £8,000 and takes 5 to 10 working days. You should receive an Electrical Installation Certificate, and the work must be notified to building control under Part P.
Signs your house may need rewiring
- A fuse box with rewireable fuses rather than circuit breakers.
- No RCD protection.
- Black rubber, lead-sheathed or fabric-covered cable.
- Brown or black round-pin sockets, or sockets on skirting boards.
- Scorch marks, buzzing, burning smells or regular tripping.
- Too few sockets, leading to extension leads everywhere.
An Electrical Installation Condition Report (EICR) is the reliable way to know. Defects are coded C1 (danger present), C2 (potentially dangerous), C3 (improvement recommended) and FI (further investigation).
What a full rewire involves
A first fix stage, where old cables are removed and new cable runs and back boxes go in, usually involves lifting floorboards and chasing walls. Plastering follows. At second fix, sockets, switches, lights and a new consumer unit are installed, then the whole installation is tested and certified. Planning extra sockets, outdoor power, data points and EV charging at first fix costs little extra.
Rewiring costs
| Property | Typical cost | Typical time |
|---|---|---|
| 1 to 2 bed flat | £3,000 to £4,500 | 3 to 5 days |
| 3 bed house | £4,500 to £8,000 | 5 to 10 days |
| 4 to 5 bed house | £7,500 to £12,000 | 8 to 15 days |
Indicative figures excluding redecoration.
Certificates you should receive
A full rewire or consumer unit change needs an Electrical Installation Certificate and notification under Part P of the Building Regulations. You should also receive a building regulations compliance certificate. Keep these with your house documents.
Further reading
This guide is general information for England and is not a substitute for advice on your specific property. Planning rules differ in Wales, Scotland and Northern Ireland. Always confirm with your local planning authority.