Complete rewire needed, so says the sparky

[WellMan]

I have a small London apartment which has developed a short in one of the power circuits.

The electrician couldn't find the problem, insisted on conducting a full EICR.

Now he is insisting on a full rewire on the basis of "failed" insulation resistance tests. However, for all but the failing circuit these come in a 1.79 MegaOhms. He has marked this as a C2 failure on the EICR.

Now from all the research I have done, anything above 1 MegaOhm is fine for BS7671, not that there is any compulsion to comply with BS7671 for an old installation. Sounds like a complete scam to me, or am I missing something?

 

[RF Lighting]

Your IR values should be over 1000MΩ in an ideal world. Anything over 100MΩ is great.

1MΩ is an indication that something is very wrong. Whilst it's compliant with the regs, all it really means it that the value hasn't yet dropped low enough to start blowing fuses.

An EICR is carried out to the current version of BS7671 and anything which does not comply must be noted down on the report.

 

[WellMan]

Thank you RF for quick reply.

So, whilst this is not ideal, it does not necessitate an immediate and complete rewire, and should be a C3 on the EICR?

 

[RF Lighting]

Does it matter what I think. It's pretty clear you've decided that your electrician was a scam artist and you're not going to have any work done to make your installation safe.

 

[deadshort]

What is the "failing circuit" and when was the 'apartment' last rewired ? I assume it has a tenant.

Kind Regards,

DS

 

[ban-all-sheds]

Code C2 (Potentially dangerous)
This code should be used to indicate that, whilst an
observed deficiency is not considered to be
dangerous at the time of the periodic inspection, it
would become a real and immediate danger if a
fault or other foreseeable event was to occur in the
installation or connected equipment.
The person ordering the report should be advised
that, whilst the safety of those using the installation
may not be at immediate risk, remedial action
should be taken as a matter of urgency to remove
the source of potential danger.

In this case C2/C3 is not cut and dried.

Your IR values, whilst technically OK, are so far below what you should reasonably expect that there is clearly something wrong. And you've already had one circuit "develop a short". Maybe if it happens again you'll get a fire?

Also, this electrician has been there, poked about, seen what things look like as well as how they test out, and has decided C2 is appropriate. Nobody here has done that, so it is very hard to argue that he was wrong.

 

[ban-all-sheds]

What is the "failing circuit" and when was the 'apartment' last rewired ?

Rewired or "rewired"?

I'm wondering how old the place is and wondering (well, OK, speculating) if the electrician suspects a "cut'n'shut" job done on old VIR cables?

WellMan - are you saying that the location, and cause, of the fault has not yet been found? How much inspecting did the electrician do?

 

[WellMan]

Code C2-

Code C2’s are regarded not as severe as C1’s but are deemed to be dangerous or to be able to cause a dangerous situation arising if the circuit is used under certain conditions. A C2 will cause a certificate to be classified as ‘Unsatisfactory’, and can be considered to be like your car failing its MOT.


Code C3-

If you have code C3’s on your certificate, then this usually mean that the issue is to do with the evolution of the electrical regulations. As the regulations change and new technologies come on the market, so the systems that are installed have become safer. So while an installation that was fitted twenty or thirty years ago might have seemed safe at the time they are not considered to be so safe now. C3 conditions can be commented on an EICR and the certificate will still be deemed to be ‘Satisfactory’. When C3’s are rectified then this will bring the installation up to date, and hence make the installation safer.

Well the guy has also put a C2 on the consumer unit not being compliant with BS7671. Surely this is a C3?

Whilst the low resistance values are not ideal, surely if they are within the bounds of BS7671, then they have to be categorised as C3.

According to NICEIC one of the criteria for a C2 is

Insulation resistance of less than 1 MegaOhms between live conductors connected together and Earth, when measured at the consumer unit with all final circuits connected.

http://www.niceic.com/Uploads/File5634.pdf


I believe that only one of the C2 items on the EICR is correctly a C2. This is important for keeping the tenant happy, who is now convinced the place is a death trap.

EDIT:
There's no VIR, the place was wired in the 80's. Whilst it's not great, I feel the electrician is overstating the problems, and dodging the hard work of finding the fault.

 

[aesmith]

Your IR values, whilst technically OK, are so far below what you should reasonably expect that there is clearly something wrong.

Out of interest, what sort of fault could cause IR values in that sort of region?

 

[EFLImpudence]

However, for all but the failing circuit these come in a 1.79 MegaOhms.

Are you saying this is a combined IR on all the remaining circuits?

If so, as DS asked, what is the value for the faulty circuit?

 

[ban-all-sheds]

Well the guy has also put a C2 on the consumer unit not being compliant with BS7671. Surely this is a C3?

That would depend on the non-compliance.

Lack of an RCD, for example, could become a real and immediate danger if a fault or other foreseeable event was to occur in the installation or connected equipment.

Whilst the low resistance values are not ideal, surely if they are within the bounds of BS7671, then they have to be categorised as C3.

They don't have to be. What they do have to be coded as is what the electrician, who has exercised reasonable skill and care when carrying out the EICR, thinks, to the best of his knowledge and belief, they should be.

I believe that only one of the C2 items on the EICR is correctly a C2.

But you did not carry out the EICR, and you are not qualified to do one, or to criticise one.

This is important for keeping the tenant happy, who is now convinced the place is a death trap.

With the cause of the fault unknown, and the way-below-par IR figures for the other circuits he might be right. He is certainly justified in being worried.


You have paid a professional electrician for his professional opinion, and you don't like what it is. Maybe he is overstating the problems. Maybe he is seeking to inflate the job into a complete rewire. Maybe he is trying to avoid the hard work of finding the fault. Maybe he is very experienced and has considered the general appearance and state of the installation in conjunction with the IR values and has judged the C2s to be justified.

These are all possibilities to consider, but really your only option is to get a second opinion from another electrician who actually goes and inspects & tests the flat. Opinions from people here are of no use to you - you argue when they contradict your view that the electrician is scamming you, and even if you did get support for that position here it would do you no good, because you have got an EICR, and it does say that remedial work is pretty urgent, so as a landlord you cannot just ignore it.

There's no VIR, the place was wired in the 80's.

PVC cables do not last forever, but unless they have been subjected to extreme and prolonged stress they ought not to be in such poor condition after 30 years - they ought to last 20 years when run at maximum temperature 24x365.

http://www.basec.org.uk/News/Basec-News/Life-Expectancy-of-Cables

Please accept that something is wrong. What it is may still be unknown, but those IR figures are not good at all for 30-year old PVC cables in a domestic dwelling.

I feel the electrician is overstating the problems, and dodging the hard work of finding the fault.

Get another opinion, and make it clear that any remedial work will be given to somebody else, so there's no incentive for them to invent things.

 

[ban-all-sheds]

Out of interest, what sort of fault could cause IR values in that sort of region?

Damaged insulation (misuse, overloading, sub-standard cable, rodent damage etc). Damp in sockets/switches/junction boxes.

 

[flyingsparks]

Have you got a copy of the test Results? It sounds like he has done an insulation test on the whole board and put the result as 1.7M ohm where as there could be one circuit causing the low result, and the rest could be fine. If this is the case then I think you have a good reason to doubt him, as it could well be that some Remidials work on one circuit would rectify that low IR reading.

 

[JohnW2]

Have you got a copy of the test Results? It sounds like he has done an insulation test on the whole board and put the result as 1.7M ohm where as there could be one circuit causing the low result, and the rest could be fine. If this is the case then I think you have a good reason to doubt him, as it could well be that some Remidials work on one circuit would rectify that low IR reading.

That would obviously make sense - but if the OP meant what he wrote (and had understood correctly), then is sounds as if that was not the case...

Now he is insisting on a full rewire on the basis of "failed" insulation resistance tests. However, for all but the failing circuit these come in a 1.79 MegaOhms. He has marked this as a C2 failure on the EICR.

As you say, if a record of the test results is available, that ought to clarify the situation.

Kind Regards, John

 

[deadshort]

In the 80's it was the 'normal' for a customer to want more sockets and they would rewire the power, but not the lighting,particularly in older conversions or flats due to the "mess" and replastering of ceilings. As has been advised, i would get a second opinion,we still have not been given the details of the circuit that "shorted" ?


kind regards,

DS