Home Electrical Installation Rewire

The most common problem with old Electrical Installation is that it can cause fire and major disruption. Old Installations are not covered by part P regulation at least you carrying a lot of works as partial rewiring.

When you buying a property I advise to make sure you ask for an electrical condition report before buying, (you might be surprised). And is good to think ahead what work the house will require, and to have some estimates, before you put the offer in.


  • Your house usually need a rewire when is too old as over 25 years old and doesn’t fit anymore with current lifestyle and demand we require from the electrical installation.

  • IF you plan to make loft extension or kitchen extension you better go with adding a new fuse box to the system that will hold the new build part.



The best way to know if your house has been rewired is to get an Electrician to carry out a visual inspection, or yourself have a look at the fuse box if is a cast in with big square fuses the are cable wired it is an old installation that might need rewiring.

If there is trunking along the skirting and surface mounted sockets or switches again it has been partially rewired, but in itself the main installation might be very old and in need of rewiring.

Another clue is to look at the color of the cables, red black and green are the old colors, it means the installation could be as old from 30 to 60 years.



If the wiring is not PVC coated then more than likely the house will need rewiring. If the electrical installation has old rubber insulated cabling, used until 1960 or lead insulated cabling used until 1955.

It will need rewiring as cables could get rotten and break down causing short circuit or could cause fire and potential electrocution.

In certain situation a house electrical installation could get away with partial rewiring and upgrade to main earth and bonding.

If a new full rewire is required make sure you choose wisely a reputable Electrical firm or Electrician.

In order to know the Situation of your electrical installation before exchanging contracts you can arrange to get a qualified electrician to carry a survey.

  • An will charge for a visual inspection from 90 to 150.

  • And for a full inspection and testing written report from 180-350



More than likely an occupied property will take longer and cost more than rewiring an empty property apart of this rewiring is disruptive and messy and happens in two stages:

First fix include preparing the routes as lifting floor boards chasing walls drilling in the joists to allow for cables to be run, cables will be pulled fixed and protected with caping or oval or conduit depending on job specification and client request.

Second Fix part includes the contractor coming back after plastering has been done and finish installing lights, sockets, spurs, kitchen appliances, smoke alarms, heat alarm, underfloor heating and everything else that is included within  the contract.

The best way to prepare your drawings is to go room by room and draw where you need the switches the lights sockets and so on.

In these days we are more technology orientated more then ever and with years to come more is to come, therefore is good to plan ahead for home cinema theatre system, data cables, mood lights, bathroom tv, cctv, electric car, door bell, all this jobs need to be planned ahead.




The cost of rewiring with standard sockets lights and switches can start from 1500-2000 for extension. A 3 bed house could cost from 3500-4500 the prices vary depending how accessible is the property, where is located and to the complexity of the finish.

Don’t forget to specify about two-way switching.

If the mains connection and meter needs moving, this needs to be undertaken by the local electricity utility company. There is a cost associated and a few weeks notice required.

(MORE: Electrics Stay Safe )




Earth bonding, known as equipotential bonding and cross bonding, make sure it is done as in the case a radiator or water pipe or gas pipe becomes live, by having the earth bonding done this will not lead to electric shock. Even if an old installation that doesn’t have bonding will require it.

You can see if your house have earth bonding by looking for green with yellow strips cable at the gas meter and water meter. If they aren’t there they should be in accessible place of first entry point in the building.

Electrics in Special Zones

There are special zones and restrictions in wet areas, because there are risks of electrocution no sockets are allowed too close to wet areas but only shaver sockets within a certain distance from splashes of water.

The light in the bathroom should be ip rated water tight and condensation tight.


Zone 0: Inside the bath or shower. Any fittings used here must be SELV (max 12V) and be rated IPX7 (protected against immersion in water).

Zone 1: Above the bath or shower to a height of 2.25m. A minimum rating of IPX4 is required.

Zone 2: The area stretching to 0.6m outside the bath or shower and above the bath or shower if over 2.25m. An IP rating of at least IPX4 is required.

Zone 3: Anywhere outside zones 0, 1 and 2. Where water jets are not to be used for cleaning purposes, the general rules of BS7671 apply. For detailed information, refer to the I.E.E. Wiring regulations (BS 7671: 2001 Section 601).


Bibliography: Certsure LLP Pocket Guide 1-2 Rev 2  01/15


Be careful when choosing an Electrician, others advertise as electricians, having no qualifications.  They thrive on the basis that you don’t understand what they do and, as a result, overcharge for shoddy, and often dangerous, work.

Useful contacts


Bibliography:   27 June 2021

BS 7671:2018 Requirements for Electrical Installations        4 July 2021

Open chat
Can we help?