The 50plus

Head office: 110A High Street Chesham Bucks HP5 1EB 0845 22 50 495

The 50plus is a trading name of The 50plus Organisation Limited 1 1 0 A , H I G H S T R E E T C H E S H A M H P 5 1 E B Registered in England. Number 3590045 T E L E P H O N E 0 8 4 5 2 2 5 0 4 9 5

Registered office: 31A, The High Street. Chesham HP5 1BW E - m a i l : e n q u i r i e s @ t h e 5 0 p l u s . c o . u k W e b s i t e : h t t p : / / w w w . t h e 5 0 p l u s . c o . u k

Do I need a rewire? 50plus director Roger Runswick looks into replacing a fuse box and how to tell if your house needs a rewire. 50plus is frequently approached with an enquiry about rewiring or replacing a fuse box. So what does this involve and how does one know it's necessary? Let's start with the fuse box. Most of us know we have in our house what most people still call a fuse box. Modern versions are called a consumer unit. The fuse box provided a means of distributing the incoming power to individual circuits (e.g. power sockets or lighting) and provided partial protection against faults on those circuits by placing a fuse in the live wire of the circuit. A consumer unit does the same job as a fuse box but with additional safety features. The fuses are replaced with 'miniature circuit breakers' (MCBs), which can be reset if they trip. Units called 'residual current devices' (RCDs) provide additional and vital safety. The great benefit of RCDs is that an imbalance in the live and neutral current a causes them to trip within a specified 0.4 seconds but frequently a lot faster. If human or pet touches a wire or an appliance becomes faulty off goes the power without hurt being caused. In post June 2008 consumer units all circuits are RCD protected (prior to 2008 for several years circuits such as lights were not RCD protected). The reason for protecting all circuits is that there have been too many cases of people drilling or nailing into cables in walls, with sometimes-spectacular results. So if you have an old fuse box that perhaps looks likes one of these…..

.....then it's time to get it replaced. A typical price is around £490 inclusive. What about the wiring? Historically wiring has changed from being lead to rubber and latterly PVC with colour codes changing from red, black, green to brown, blue, green/yellow. Let’s look at what you need to look out for.

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If you have lead (grey) or rubber (black) cabling as shown on the left then a rewire is needed as soon as possible. A rewire can also needed if: - There aren't enough sockets or you find a need

for a lot of extension leads - There are no earth cable to lights (it's best if an

electrician checks this) - Your plugs or sockets get hot or have scorch

marks - Sockets or switches have wooden back plates - You have round pin plugs for anything other

than lighting

- Fuses blow regularly. One other tell-tall sign of a need for a rewire is that a lot of modifications have been made. In the UK we have something most other countries don't and that's ring-mains. This means the cable starts at the consumer unit, goes to the first point, then the next etc. and finally back to the consumer unit, forming a ring. It was introduced after World War II to save copper as it means smaller wires can be used. It does mean we have to have rules about adding sockets and circuits. These are often unknown to those who DIY resulting in some interesting but far from safe wiring. If you are refurbishing a property then a rewire is worth considering as it's a lot cheaper than undertaking the work later. Finally do remember that much new electrical work within a domestic setting must comply with Part P of the Building Regulations. If you sell your property you will be asked for the certificates. Building Control hold a record of works undertaken. Roger Runswick is a director of 50plus and a member of the Institute of Engineering technology. He can be contacted at roger.runswick@the50plus.co.uk. Prices as of August 2010.