Do i need a rewire?

[danneh]

Having just bought my new first house and finally got the keys yesterday the fun task of renovation is here . The house is a terraced house about 100 years old. At the minute plug sockets are, what you might say, sparse. Having looked at the fuse board it is an old fashioned wire fuse type with only 3 circuits (Plugs, Lights and Immersion - guessing this is for the combi boiler now as there isnt an immersion). Now my original plan was to add a few sockets on spurs but i am a little worried on whether it will be overloading the circuit bearing in mind whats going to be connected

• 3 computers, printer, router, switch
  2 tvs, videos and dvd players
  amp, sub, cd player
  phone and answer phone
  fridge, freezer, washing machine, dishwasher, mircowave etc
  alarm
  and probably more

How much (i know it #s only going to be a rough estimate) would a rewire cost? My father has got a 8switch mcd distribuiton panel he says i can have would that save me much?

 

[Damocles]

How much a rewire would cost depends on lots of things, but the price of a consumer unit is probably neither here nor there. Labour will cost a lot more than materials.

Or did you mean if you do it yourself? if you do, then make a list of all the stuff you will need and have a look at some online sellers prices.

The chances are that a 30A fuse will run all the socket power requirements of a small house. If it is done properly then you could expand the existing ring. Is the wiring itself pvc and in good condition?

If you re-do it then I would suggest having separate up, down and kitchen. This may cost more if you are paying someone, but probably not much more if you are doing the work.

It may be that you already have a lot of spurs on your ring. It is quite possible you only have a ring through one floor with spurs running up or down to the other floor.

 

[felix]

That info from Damocles is all good stuff but the need for a rewire depends on things you haven't told us yet.

1) Are the sockets standard square pin or old round pin?

2) Even if they're square, have a look at the cable behind. A common rewiring bodge was to replace only the sockets. If you find old rubber or fabric or lead covered stuff you need a complete rewire.

Since you have the offer of a free consumer unit I would take it. It's nice to have spare fuses.

 

[dabaldie]

is the lead covered stuff that bad?. i've got some under the ground floor that serves the sockets... all the rest of the house is new pvc.
i did notice that the lead is connected to what appears to be the house earth?... is that cos the sheath itself acts as a carrier?

 

[danneh]

Well been hard at it all day stripping wall paper and getting quotes for double glazing! I havent had chance examine the wiring closely yet i think that will be one of the many jobs pencilled in for sunday. Now is there an easy way to determine how the wiring is done? I have read something about turning the mains off, and then taking off 2 socket plates and twisting the wires together on one of them and checking for contintuy but im not 100% on what i am doing.

Also in the kitchen there is an old central heating timer which i presume is from the old heating (as the combi boiler has its own timer built in) how much of a job would it to be to remove that?

 

[Damocles]

Lead wiring must be quite good if you are a scrap merchant. Otherwise, it all depends. I do not know how quickly it deteriorates but it must have been there rather a long time. I would plan to replace it but it is hard to say whether it is actively dangerous without seeing it. Is the internal insulation rubber, and if so is it falling to pieces at the ends? Only, always be careful if you muck about with old rubber as all the insulation might fall off if you move it.

A socket on a ring will probably have two wires going to it. A socket with three wires is probably the start of a spur and a socket with just one cable is the end of a spur.

If it is a fused spur there must be a plate with a 13A fuse starting the spur. In that case there might be several sockets after the fuse with two cables in each, daisy chained from one to the next.

Bad news is if there are any unfused spurs which then lead on to other sockets. This is more likely the older the house. Also watch out in case anyone has imaginitively joined the ends of two spurs together forming a crossed ring. This is not inherently dangerous, except that there is no easy way to test if the wiring is sound. Hence crossed rings are banned.

Watch out in case any of the wires are loose where they are held by the connection screws on the back of the sockets. This is more likely if the cables are old stranded type rather than modern solid ones.

 

[felix]

Here's what can happen with old lead sheathed cable where the lead is the earth conductor. The lead becomes brittle and cracks leaving you with an imperfect earth. Also, the insulation within crumbles allowing the conductors to touch the lead. Worst case scenario - the lead breaks right across leaving your socket(s) with no earth, AND the live wire touches this floating earth. All sockets beyond the break now have live earth pins!