Full House Rewire in London: Costs, Disruption, and What the Work Involves
A full electrical rewire replaces all the wiring in a property — from the consumer unit (fuse board) through to every socket, switch, lighting circuit, and fixed appliance connection. In London, where a large proportion of the housing stock was built before 1970 and may not have been rewired since, this is one of the most safety-critical projects a homeowner can undertake.
When Is a Rewire Needed?
The clearest indicators that a rewire is needed:
Age: Wiring installed before 1970 used rubber-insulated cables that become brittle and dangerous over time. Pre-1965 wiring frequently used lead or fabric-insulated cables that should have been replaced decades ago. Any London property with original wiring from these periods needs a rewire.
Fuse wire consumer unit: If the fuse board still uses rewireable fuse wire rather than modern miniature circuit breakers (MCBs) and RCDs, the electrical installation is significantly out of date. Modern consumer units include RCDs (residual current devices) that protect against electrocution and fire — original fuse boards do not.
Earthing deficiencies: Older installations frequently have inadequate or absent earthing, particularly in kitchens and bathrooms where earthing requirements are most critical.
Condition report findings: An Electrical Installation Condition Report (EICR) will classify deficiencies as C1 (danger present — immediate action), C2 (potential danger), or C3 (improvement recommended). Multiple C1 or C2 findings typically indicate that a rewire is more economical than point repairs.
Planned major refurbishment: If you are undertaking a full refurbishment — opening walls, replacing plasterwork, and updating all finishes — rewiring at the same time is dramatically cheaper and less disruptive than doing it later.
What a Rewire Involves
A full rewire is a significant programme of work:
Strip out: Existing wiring, sockets, switches, and light fittings are removed. The consumer unit is isolated but typically left in place until the new installation is ready.
First fix: New cable routes are established. In a house with plasterboard or dot-and-dab walls, cables can often be run under new conduit or through ceiling voids. In solid masonry walls (common in Victorian London terraces), channels (chases) are cut into the plaster to accommodate cables, which are then plastered back over.
Consumer unit installation: A new consumer unit meeting current Part P and BS 7671 requirements is installed, typically with dual RCDs or a split RCD/RCBO arrangement providing full protection.
Second fix: Sockets, switches, light fittings, and fixed appliances are connected and tested.
Testing and certification: The installation is tested throughout and an Electrical Installation Certificate is issued on completion. This certificate is required when selling the property and confirms the work meets current wiring regulations.
Disruption: What to Expect
A rewire in an occupied London home is genuinely disruptive. Key points:
- Decoration is damaged: Chasing cables into walls means replastering, which means redecorating. Any room being rewired should be budgeted for replastering and redecoration afterwards.
- Power is isolated during work: The property will be without power in sections during the rewire. In a working household, this requires careful programming to minimise disruption.
- Duration: A full rewire of a 3-bedroom Victorian terrace typically takes 5–8 working days for the electrical work, plus plastering and decoration time afterwards.
- Access: Electricians need access to every room, every ceiling void, and every floor void where cables run.
The best time to rewire is either during a vacancy (rental property between tenants) or as part of a full refurbishment where the property is stripped back anyway.
Approximate Costs in London
Rewiring costs vary significantly depending on property size, wall construction, and specification. Typical London market rates (2025–2026):
| Property Size | Approximate Rewire Cost |
|---|---|
| 1-bedroom flat | £2,500–£4,500 |
| 2-bedroom flat / small terraced house | £4,000–£6,500 |
| 3-bedroom terraced house | £5,500–£9,000 |
| 4–5 bedroom semi-detached or detached | £8,000–£14,000 |
These are electrical-only costs and do not include plastering and decoration, which should be budgeted separately.
Part P and Building Regulations
Electrical work in domestic properties in England is notifiable under Building Regulations Part P when it involves new circuits, consumer unit replacements, or work in kitchens and bathrooms. This means the work must either be carried out by a competent person registered with a Part P self-certification scheme (NICEIC, NAPIT, etc.) or be notified to Building Control.
All reputable electricians are registered with a Part P scheme and self-certify their own work — ask for the certificate on completion.
RCB Design & Build
RCB manages full house rewires as part of larger refurbishment programmes, coordinating the electrical first fix within the wider programme sequence and managing plaster repairs and decoration following cable installation. Contact us to discuss your electrical requirements as part of a refurbishment project.