Rewiring a house | Tips to tell if your house needs rewiring

Find out when rewiring a house is required and the cost to rewire a house. At worst, faulty electrics can be a serious fire hazard and can lead to serious injury. Modern electrical rewiring adheres to strict building regulations so it typically comes down to the age of your house.

Does my house need rewiring?

rewiring a house

Are you buying a property more than 25 years old? It would be important to check that the wiring is up to date before you buy. This will give you an idea of the extent of whether the house needs rewiring and the rewiring cost so that you can factor this into your plans and potentially for negotiations with the vendors.

If you already own a property and are looking to undertake some home improvements or a conversion, it is important to know if you have old electrical wiring. Rewiring a house could change the timescale of your plans and can be disruptive to decor. So it is best to complete this early on.

In both instances, you should get an electrical conditioning report to test your home electrics. We talk more about conditioning reports and their cost later on.

circuit board rcdIs rewiring a house really necessary?

According to the homebuilding & renovating advice centre, rewiring a house is necessary:

  • If a property has not already been rewired within the last 25-30 years, the chances are it will need upgrading at least in part in order to bring it up to current standards. The wiring may be potentially dangerous and may not be able to cope with the demands of modern living.
  • If you plan major remodelling work that constitutes a material alteration as defined by the Building Regulations, it is likely that you will need to rewire part, if not all, of the property, including upgrading the consumer unit (fuse box).
  • If you are extending your home, or converting an attic or garage, this will constitute new work and therefore all of the new wiring will have to conform to Part P: Electrical Safety. All existing wiring will have to improve to ensure that it is able to carry the additional loads safely. It needs an earth to current requirements and that cross bonding is satisfactory.
  • Where you are extending or remodelling, the rest of the existing wiring does not have to be upgraded, except where upgrading is required by the energy efficiency requirements of the Building Regulations, i.e. central heating controls.

How to tell if you have old electrical wiring

It’s not always easy to spot the symptoms of old electrical wiring in a house as many of the house wiring and cables will be hidden behind walls and in the loft space. You should always take care when dealing with electrics. If you aren’t comfortable in checking whether you have old wiring or new, call an electrician!

However, here’s a few simple tips to help you understand why your home might need rewiring and how you might be able to spot it.

A good place to start is the electricity meter and fuse box (now known as the consumer unit). If there is an old-fashioned-style fuse box, with big white ceramic-style fuses, then the chances are that the property needs completely rewiring. A modern consumer unit will have circuit breakers and RCDs (residual current devices). An RCD is a sensitive safety device that switches off electricity automatically if there is a fault.

Another tell-tale sign that rewiring a house may be necessary is having a mix of different socket and switch styles. This could indicate that a partial rewire has taken place. Especially if there is evidence of surface-mounted wiring running along skirting boards and up walls. Of course, it is possible to have old wiring to a new light fitting so you might need to carry on searching.

In some rare cases of very old properties, you may still find round pin sockets or original dolly switches, both of which are a sure sign that a rewire is necessary!

Another clue is the colour and style of the cabling. You should be able to find some exposed cables at light fittings, around the fuse box. Modern electrical wiring has PVCu insulating cable and should be either white or grey.

If you are in any doubt, call an electrician. It’s better to be safe than sorry!

rewire a houseWhat if it has not been Rewired?

Unless the wiring is the modern PVCu coating type, then a rewire is likely to be necessary. If you see any old rubber insulated cabling, fabric insulated cabling (used until the 1960s), or lead insulated cabling (used until 1955) then it needs replacing as the insulation can rot and/or break down, leading to short circuiting: a fire hazard and potential electrocution.

Even older PVCu cable may need replacing if it is not twin earth cabling (with a second earth cable running within the outer sleeve). But this may only be evident if you are able to remove a switch or socket faceplate and look closely.

If you are in any doubt, assume that a total rewire is the requirement and budget accordingly. It may be that the system can be improved for less money by upgrading earthing and cross bonding.

How much does an Electrical conditioning report cost?

If you’re looking to buy a house, you should be able to get access to the property for an electrical conditioning report. This will enable you to find out exactly what work is required and more importantly, does the house need a rewire. A conditioning report will also give a good indication of how much it will cost.

An electrician will typically charge £150 – £200 for a survey with conditioning report. The cost will depend on the size of the house.

How much to rewire a house?

We are often asked, how much does it cost to rewire a house? The price of rewiring a house will vary depending on it’s size. Also how accessible/empty the property is and the complexity and standard of the finish. As a rough guide, the average cost of rewiring a three-bed house is £3,500.

However, often a full rewire can be avoided providing the existing cabling is sound and able to carry any additional loads. It also may be possible to upgrade it by ‘simply’ adding a modern consumer unit. This will be established during the electrical conditioning survey.

How long will rewiring a house take?

Again this will vary depending on the size and accessibility of the house. As an example, a kitchen rewire may take two days. A three-bed semi probably two days to first fix, then the same again to second fix. A larger property will take much longer.

When to rewire a house?

If the house needs rewiring, it should be undertaken at first fix stage. Ideally at the same time as any central heating and plumbing work and before plastering. New domestic wiring cannot be surface mounted.  Installation is likely to involve lifting carpets, floorboards and possibly the skirting boards too. Channels in the walls will need routing and possibly in some ceilings if there is no access from above.

As well as installing new cabling, first fix stage will involve fitting new back boxes for all sockets and switches. In addition to rewiring for all power and lighting circuits, it is a good opportunity to rewire for modern central heating controls, alarms, smoke detectors and doorbells, to add outdoor lighting and sockets, and to rewire the telephones and television aerial sockets.

At this stage is would be good to think about the spec for two-way or even three-way switches for hallways, landings and rooms with more than one doorway.

Something to bear in mind; if the mains supply or meter needs moving, this will have to be done by the local electricity utility company. There will be a separate charge and you may need to give several weeks notice.

The second fix work involves fitting sockets, switch plates, light fittings and the consumer unit.

Electricians usually prefer to work on a supply-and-fix basis, meaning they provide labour and materials (wiring, back boxes etc.). This ensures they have responsibility for the quality of the materials and the work done. For second fix, some electricians will be happy for you to supply your own sockets, switches and light fittings, although it’s good to liaise with the electrician throughout this process.

Finding an electrician to carry out your rewire

For a house rewire electricians typically work to a fixed price. Although it is usual to agree rates for each additional power point, switch or light fitting added. The price will be calculated using measured rates according to how long they expect the work to take, how many circuits there are and the number of power points, light fittings and switches.

They will also take into account whether the work is a new build or extension, in which case they can just face-fix the circuits, or a renovation, in which case they may have to lift floors and chase out plasterwork to conceal the wiring which, therefore, takes longer and costs more.

You can try and keep costs down with a friendly electrician by doing some of the prep work, such as chasing out plasterwork, lifting floorboards and generally making access easy to save time.

Rewiring a house

So, whether you have a house that is 25 years old or more, you think you have electrical problems or you’re wondering, does my house need rewiring, contact Punton Electrics today. We can carry out an electrical conditioning survey and let you know the cost to rewire a house.

Useful contacts:

Electrical Safety First: 020 3463 5100;

ELECSA: 0870 749 0080;

NAPIT Certification: 0870 444 1392;

NICEIC Certification Services: 0800 013 0900

Punton Electrics: 01590 679081