What affects the cost of rewiring a house?

Why rewiring prices vary so much

A rewire is labour-intensive: lifting floors, cutting and filling chases, running cable, connecting every point and testing the result. Anything that changes how long those tasks take changes the price, so two houses with the same number of bedrooms can be priced a long way apart. House rewiring covers how Firefly approaches the work itself.

The main cost drivers

Size and number of circuits

More rooms means more cable, more circuits and more time. A house over several floors, or with a loft conversion or extension, typically needs more circuits than its bedroom count suggests.

The number of points

Every socket, switch, light, fused spur, outdoor fitting and data point is a position that has to be wired and connected. A rewire is also the cheapest moment to add them, so the specification you choose, such as double sockets throughout, extra lighting circuits or outdoor sockets, feeds straight into the price.

Access to floors, walls and lofts

Suspended timber floors and an open loft make routes simple. Solid floors, flooring that cannot be lifted without damage, ceilings with no void above and hard masonry walls all add labour, and sometimes more making good or surface-mounted trunking where a concealed route is impractical.

Occupied or empty

Working in a lived-in house is slower. Furniture has to be moved and protected, power restored at the end of each day, and rooms tackled one at a time. An empty house can usually be rewired for less.

Kitchen and heavy loads

Electric cookers and hobs, electric showers, immersion heaters, electric underfloor heating and car chargers each need a dedicated circuit sized for the load. The more of them there are, the more circuits there are to install and the more the consumer unit has to accommodate.

Outbuildings and outside

A garage, workshop, garden office or outdoor lighting needs its own supply from the house, often in armoured cable and sometimes buried, with its own protection. The distance and the ground it crosses both affect the cost.

The consumer unit and earthing

A new consumer unit is normally part of a rewire. Whether circuits share RCD protection or each has its own device changes the price, and if the main earthing or protective bonding needs bringing up to standard, that is further work.

What is being kept

A partial rewire that keeps circuits which test well costs less than replacing everything. Whether that makes sense depends on how sound the remaining circuits genuinely are.

Making good: agree where it stops

This is the part of a rewiring quote most worth reading closely. Rewiring leaves chases in walls, holes in ceilings and lifted floorboards, and quotes differ in how much of that they put right. A quote should make clear:

• whether chases are filled and left ready for decorating
• whether any plastering or skimming is included, or needs a plasterer
• whether floorboards are refixed, and how damaged boards are dealt with
• who lifts and relays carpets and other flooring
• that redecorating is a separate cost

Changes after first fix

Once cables are run and walls are made good, moving a socket or adding a light means cutting into finished work. A change at that stage costs noticeably more than the same position would have cost on the original plan. Walking round the house before first fix and deciding where the furniture, televisions, desks and outside lights will go is the simplest way to keep the price where it started.

Hidden problems are the other source of extras: a junction box buried in a wall, damaged joists, or an earlier alteration that only shows once the floor is up. A good quote explains how anything unexpected will be raised and priced before work carries on.

What a rewiring quote should include

• a written scope: what is being rewired, what is staying, and the number of points and circuits
• the consumer unit and protection being fitted
• exactly what making good is included
• how the work will be staged if the house is occupied
• how changes and unexpected findings are priced
• testing and certification on completion, including Building Regulations notification for the new circuits

Keeping the cost down without cutting corners

• have the work done while the house is empty
• combine it with other renovation, so floors and walls are only opened once
• decide every position before first fix
• keep circuits that testing shows are sound
• stage the work if that suits your budget, agreeing where each stage ends

Testing, certification and the protection the installation needs are not the places to save. How long the work takes is covered in How long does a house rewire take?

How Firefly prices a rewire

I do not publish a fixed rewiring price. Each rewire is priced after a visit to see the floors, the loft and the board, and the quote is free with no obligation. Where parts of a house have already been rewired, the Winchester rewiring page explains how sound circuits are kept, and the Southampton rewiring page covers the work in the city.