No ring main Ask questions and find answers to many subjects relating to electrics and electrical work

[nameless]

We've had a 17th edition unit installed and the electrician says we don't have a proper ring main. He said that the socket fuse was too high at 30 amps and has now split the load over 2 cables and 2x 20 amp fuses. He warned that if we use tumble dryer while wash m/c is heating the fuse may blow.
Another electrician was supposed to have checked all of this a long time ago, but didn't mention it. We are very angry about that.
We've said we will have it all re-wired but obviously dread the damage to the decorations etc. Also our loft has recently had more insulation and been boarded.
If we don't have it done and just leave it are we safe or likely to have a fire? Would it cancel the house insurance?
I want to have it done but my OH is very reluctant, especially as it will cost around £1000.00. Does that seem the right price?
I'd also appreciate advice about how the re-wiring is done, from loft down? We need to know to work out what has to be moved etc.

[Neil54]

It may not be necessary to rewire. If a ring has become disconnected it may be possible to join it back up again.
It would take some time to trace and identify all the wiring and you may be faced with a £200 bill to find out you need to be rewired after all.
There are not many houses left with old rubber insulated cables, if you happen to have rubber cables then a rewire would really be required anyway.

[ericmark]

Do remember there is a little guess work here. So to try to explain.
1) Since the break in the ring has been identified and correct size overload for cable has been fitted there is no danger. Unless you have missed something.

2) To stop large appliances from tripping MCB/RCBO easiest method is either install some dedicated supplies or repair ring. It does not require a full re-wire if this is only fault.

3) I suspect they are not fuses but circuit breakers so even if they do trip it's no big deal.

4) No one other than who laid the insulation and loft boarding knows how the cables are cooled under those boards. Lights are likely to be OK as most lights are only 6A and cable is well above that. You are unlikely to have any socket supplies so the only one to worry about is likely to be shower supply if any. But without a crystal ball no electrician can know without lifting boards.

5) It is very easy to break a ring main and this is why the whole system should be checked every 10 years or change of occupant. If for a minute we assume the electrician a long time ago did his job correct then it is likely something done between the two dates which has caused the problem this may help you find fault.

6) If electrician from a long time ago did proper job then he would have raised paperwork to back up what he has said. The Schedule of test results should show readings obtained at the time. The new electrician should have also produced a Schedule of test results and by comparing the readings you should be able to work out if the ring was or was not intact when the long time ago guy tested it.

7) The £1000 price tag seems cheap but this varies so much from area to area and with size of house it is impossible to really comment. Except to say is this for full re-wire or part re-wire? As since the new electrician seems to have done a good job I would have though he would have quoted to get around the problem rather than full re-wire. And so I wonder if there is something missed in the telling?

To day there are some moves away from the traditional ring main. Mainly to do with the adding up of earth leakage and as a result RCD's tripping with no fault. Much would depend on design of the house and how cables can be run.

In the past for kitchens I have run an external cable to feed a grid switch and from there all the large kitchen appliances. Since the grid switch can take a mixture of switches and fuses it can act as a mini-consumer unit and can be supplied with 4mm cable able to take the full 32A supply.

This may not be the appropriate approach with your house but it shows how there are many ways to solve a problem. I think you need to ask your electrician a few more questions? Some one on site is likely to give better advice than someone remote. But only if asked in first place.

So my advice is to get an electrician (not necessary any you have used before) to come to the house and advise on best options. Re-wire does seem a bit drastic.

[nameless]

Thank you both for the advice. Unfortunately we know absolutely nothing about electrics so have to accept anything we are told.
Our house is 3 bedroomed semi built 1927. We have 14 sockets, some double. We have no paperwork for previous electrical work done to the house. 14 years ago when we moved here we had the black wiring upstairs removed and a consumer unit put in. The electrician was supposed to have checked that all was safe and ok. We had no knowledge of tests he should have made and have only a receipt from him.
On Friday when the new electrician came to move a cooker socket and update the box he advised that we don't have a ring main, said the socket tests vary too much and so probably sockets are spurred from one another. I presume he saw the wiring when he pulled up boards for the cooker cable. He says the lights are ok and don't need work.
Unfortunately we do not know what other questions we should ask. Please can you give me an idea? From another forum I learned that we needed someone Part P approved so went through the NICEIC website to find a contractor. I will try to get another electrician but people do not seem to return calls.

Thank you very much for the advice. We are very much out of our depths. At present have also had to claim after a waterleak in the kitchen so are very upset about it all.

[moggy1968]

there are other providers other than NICEIC such as ELECSA and NAPIT
registration does not prove the guy is nsy good though, only that the inspector was happy when he visited!!
if your in the south try checkatrade.

this is a problem I have come across when fitting new consumer units on a couple of occassions. usually the problem cannot be recrified due to construction or decoration in the house, so the only option is to down grade the circuit to 2 radial circuits, thisis the correct and safe way to manage this problem if proper repairs cannot be made. the main problem though is why the ring has no continuity, if it was originally a ring. this may mean you have a loose cable flapping about someowhere which could cause shorts and tripping.

he will have discovered this when doing his testing from the readings he got, not by a visual inspection.

[sparx]

Hi. from what your last leckie states I believe he is very genuine since the reasons he says indicates that rather than just doing a quick consumer unit change he has correctly carried out full end-to-end tests on what should have been a ring circuit.
Having found the ring to be broken he has done what is the cheapest option for you and created two radials giving you in effect 40A rather than 32A worth of available power.
As for finding an approved electrician what's wrong with the one you have? As he has already changed the consumer unit he must be 'Part-P' registered.
If you want to find another one, type in 'Competant Person Register',
With your post code you should find someone registered with either ELECSA, BRE, BSI, NAPIT, or NICEIC all of whom keep lists of registered enterprises. OR try Trading standards 'Buy with confidence' list.
or governments 'Trust Mark Approved' list.
regards Sparx

[nameless]

Dear Sparx,

Thanks very much for the information. Before I got through to the electrician I tried to contact several other people registered with NICEIC, some didn't return my call and one registered for "Domestic" only deals with petrol stations.

The one who came is very competant and has obviously done the right things. We were advised to get more than one quote and advice because we are so ignorant of electricity matters. The electrician who came 14 years ago was supposed to advise us but didn't. We would have had all of this corrected then. It has made us lose our trust in people. (Previously we believed everyone, only had one quote for everything and never queried the price.) My friend has now recommended a NICEIC Part P qualified electrician who has worked on her home. He will come to advise & quote tomorrow.

Thanks again.

[ericmark]

14 years ago any one could call themselves an electrician there were no checks and even the good ones did not need to satisfy a higher authority and tests and checks were often missed. Other than with new houses paper work was often not completed.

Today that has in the main changed and most electricians will do all the tests required mainly due to Part P. It has resulted in "jobs worth" where electricians know any job they do may be checked by an inspector and they can't afford the chance of losing the ability to sign off their own work. So they will refuse to do any job not A1.

So unlikely you will ever get repeat of 14 years ago if you use registered electricians. 14 years ago there were no registered electricians.

[nameless]

Moggie1968
We've just had the other electrician here and he said our readings on the lights also only just pass the guidelines. When the last electrician moved the cooker socket on Friday I had asked him to put complete new wiring from the cookerpoint to the board. He hasn't done this, the wiring to the box is old, as I discovered last night and was confirmed today. I am very angry.

Today's electrician has recommended a complete re-wire, 2 blokes approximately 1 week to do that?

I am thinking of selling up and living in a tent.

[nameless]

Going back to the cooker wire. I saw the old cable which was taken from the cooker and so know that the cable there has been replaced. As the cable to the unit is old there must be a join somewhere. Can I rest assured that joining the cable will not result in a fire? The chap today studied the test report from Friday and said it should be ok.
Thanks