A Guide to Electrical Rewiring for London Homes

A guide to electrical rewiring starts with a practical question: is the installation still safe for the way the property is used? Many London homes have had new kitchens, loft conversions, electric showers and extra sockets added over decades, often without the electrical infrastructure being upgraded at the same time. A full rewire is disruptive, but it can remove serious safety risks, improve capacity and provide the certification needed for sale, letting or planned property management.

When Electrical Rewiring Should Be Considered

Age alone does not automatically mean a property needs rewiring. A well-maintained installation can remain serviceable for many years, while a newer installation may need attention if it has been altered poorly or damaged. The condition of the wiring, consumer unit, earthing, protective devices and accessories is what matters.

Warning signs should be investigated by a qualified electrician rather than treated as minor inconveniences. These include regularly tripping circuits, flickering lights, warm sockets or switches, burning smells, damaged cables, cracked accessories and electric shocks or tingles from taps or appliances. An old fuse box with rewireable fuses, a lack of RCD protection or a consumer unit that cannot accommodate modern circuits may also point towards a larger upgrade.

For landlords and managing agents, the decision is often driven by an Electrical Installation Condition Report, known as an EICR. In England, private rented properties must have their electrical installation inspected and tested at least every five years, or sooner where the report recommends it. A report may identify observations that can be repaired locally, but widespread deterioration, outdated protection or repeated defects can make a full rewire the safer and more cost-effective route.

A property that is being stripped back for refurbishment is another clear opportunity. Rewiring before plastering, decorating, fitting a kitchen or installing new flooring avoids paying twice for access and making good. This is particularly relevant in older London terraces, converted flats and rental properties where previous alterations have left circuits difficult to trace or maintain.

What a Full Rewire Involves

A full rewire replaces the fixed wiring and normally includes a new consumer unit, new circuit protection, sockets, switches, lighting points and relevant earthing and bonding work. It is not simply a consumer unit change. Replacing the board can improve protection, but it cannot correct deteriorated cables, overloaded circuits or poorly routed wiring elsewhere in the property.

The work usually takes place in two stages. First fix is completed when walls, ceilings and floors can be accessed. New cables, back boxes and routes are installed before surfaces are closed. Second fix follows after plastering and decorating work, when sockets, switches, light fittings and the consumer unit are connected, tested and commissioned.

The exact scope should be agreed before work begins. A clear quotation should state whether it includes chasing walls, lifting floorboards, making good, new light fittings, smoke alarms, external supplies, data cabling and any specialist items such as electric heating, ventilation, induction hobs or EV charging provision. Assumptions create disputes, especially where a property is occupied or has unusual construction.

A competent electrical contractor will also assess load demand. Modern households commonly use more electricity than the original installation was designed for. Kitchens may require several dedicated circuits, while showers, ovens, heat pumps and charging equipment can place significant demand on the supply. In some cases, the existing incoming supply or meter arrangement must be considered before major additions are made.

Planning a Rewire in an Occupied Property

A rewire causes dust, noise and temporary loss of power. That does not mean a household must always move out, but it does mean the programme needs to be realistic. A vacant property is simpler and often faster. In an occupied home, electricians can sometimes work room by room and maintain a temporary supply, although this may extend the programme and limit access to certain areas.

Before the work starts, decide on room layouts rather than copying the old socket positions. Think about where beds, televisions, desks, routers, appliances and lamps will actually sit. This is the point to add bedside charging points, under-cupboard kitchen lighting, bathroom extractor fans, outdoor lighting, security supplies and adequate sockets for home working. Adding these after decoration is possible, but it is less tidy and usually more expensive.

Property managers should also plan communication with tenants. Give clear notice of access requirements, expected power interruptions, dust control arrangements and the person to contact if an issue arises. For multi-unit buildings, works may affect communal supplies, fire alarm interfaces or access routes, so coordination is essential.

A typical two or three-bedroom property may take around five to ten working days for the electrical installation, depending on access, construction, specification and whether plastering is included. Listed buildings, concrete structures, occupied flats and properties with limited floor voids can take longer. No contractor should promise a fixed timescale before surveying the building and understanding the required finish.

Safety, Testing and Compliance

Electrical work is safety-critical. It should be designed, installed and tested by a properly qualified electrician working to the current edition of BS 7671, the UK Wiring Regulations. In England, certain domestic electrical work is notifiable under Building Regulations Part P. A contractor registered with a competent person scheme, such as NAPIT, can notify eligible work and provide the appropriate certification. Where that route is not used, building control requirements must be addressed.

At completion, the contractor should provide an Electrical Installation Certificate for the new work, together with schedules of inspections and test results. For notifiable domestic work, a Building Regulations compliance certificate should also follow. Keep these documents with the property records. They demonstrate that the installation was tested, support future maintenance and are commonly requested during a sale, tenancy review or insurance query.

Do not confuse a visual check with proper testing. Electrical testing confirms the effectiveness of protective measures that cannot be judged by appearance alone, including continuity, insulation resistance, polarity, earthing and RCD operation. A clean new consumer unit is not proof that the installation behind it is safe.

Costs and Choices That Affect a Rewire

The cost of a rewire depends on the property rather than a standard price list. Size matters, but so do the number of circuits, access to floors and walls, the chosen accessories, the condition of the existing installation and the extent of making good. A studio flat with accessible routes is very different from a large occupied Victorian house with solid walls and several reception rooms.

The main cost drivers are usually:

• the number of sockets, lighting points and dedicated circuits required;

• whether floors can be lifted and walls chased without specialist work;

• consumer unit specification, surge protection and RCD or RCBO arrangement;

• additional systems such as smoke alarms, extractor fans, garden power and security lighting; and

• making good, plastering and decorating after first-fix work.

The lowest quote is not always the lowest overall cost. A vague allowance can exclude testing, certification, chasing, waste removal or remedial work discovered during installation. Ask for a written scope, confirmation of what is excluded and a clear approach to variations. For landlords and organisations managing several properties, consistency of certification, reporting and record keeping is as valuable as the installation itself.

There are also cases where a partial rewire is appropriate. If testing confirms that part of the installation remains safe and suitable, a contractor may recommend upgrading specific circuits, replacing the consumer unit or renewing wiring during a kitchen or extension project. The right answer depends on test results, future demand and how long the property is expected to remain in service before further refurbishment.

Choosing the Right Electrical Contractor

Use a contractor who can survey the property, explain the proposed work plainly and take responsibility for testing and certification. Check that they are NAPIT Registered or registered with another recognised competent person scheme, fully insured and able to provide written documentation on completion. For urgent faults, 24/7 Emergency support is valuable, but planned rewiring still requires careful design and programme control.

K-TEK Plumbing Ltd provides electrical call-outs, consumer unit upgrades, full rewires and EICR reporting across London and the M25, with NAPIT Registered electrical work and a clear compliance-led approach. Whether the property is a family home, a single rental flat or part of a larger managed portfolio, request a survey before defects become an emergency or a refurbishment reaches the finishing stage.

A rewire is easiest to manage when it is planned before the walls are closed and the tenancy, sale or renovation deadline becomes critical. Get the installation assessed early, keep the certification organised and make decisions based on the condition of the property rather than guesswork.