Why do i need a rewire when i've passed inspection with no issues?

davidc123 · Feb 25, 2023

Hi

I'm having some work done at my house and the electrician has said we need a full rewire. I'm a bit surprised given that we passed an inspection 2 years ago and it raised no issues at all. We've just been told that the wiring is illegal and needs changing. Maybe i'm not understanding the point of the inspection certificate, but how is it possible for the inspection to raise no issues and yet it actually needs a full rewire? I've attached a page from the report, if it helps.

Also, I'm being charged £17k + VAT for a 4 bed house, which seems high to me. Is it?

Thanks

pc1966 · Feb 25, 2023

There is no such thing a "illegal wiring". It maybe unsafe to varying degrees, but that is a somewhat different matter.

Have you go the rest of the test report (names/addresses redacted before posting)?

Can you provide some photos of the current installation, for example, around the fusebox?

To me this smells very fishy. First I would be asking the electrician for a written report on what points are failing inspection and the relevant regulations behind them (as is normal for a detailed EICR).

davidc123 · Feb 25, 2023

Thanks, i thought the illegal wiring comment was nonsense. I've attached other pages from the report and a photo of the fusebox

I'm not actually sure he looked at the fusebox though. He was more concerned about the wiring in the rest of the house, which had the older red/black colours

brianmoooore · Feb 25, 2023

Very curious about this one!
Do you have a page of the report that lists C1, C2, C3 and FI codes for the circuits?

davidc123 · Feb 25, 2023

Sorry those pages are all I have, we were given it when we bought the house in 2021

123 · Feb 25, 2023

That's an EIC for a consumer unit change rather than an EICR

Dustydazzler · Feb 25, 2023

'Illegal' Wiring

Risteard · Feb 25, 2023

brianmoooore said:
Very curious about this one!
Do you have a page of the report that lists C1, C2, C3 and FI codes for the circuits?

It's not a Report. It's merely a certificate for replacement of the DB only, so the OP appears to be misunderstanding what it is stating. It relates only to the work carried out and does not declare that the installation is fine.

davidc123 · Feb 25, 2023

123 said:
That's an EIC for a consumer unit change rather than an EICR

Ah OK, that's where the misunderstanding is. Thanks for the help.

On the other point, is 17k+vat a reasonable cost for a 4 bed house? We're having a new kitchen / diner, utility room and play room fitted too, so new points as well as a rewire of the house

123 · Feb 25, 2023

davidc123 said:
Ah OK, that's where the misunderstanding is. Thanks for the help.

On the other point, is 17k+vat a reasonable cost for a 4 bed house? We're having a new kitchen / diner, utility room and play room fitted too, so new points as well as a rewire of the house

Depends on the property, the spec of what you want, your location, whether it's occupied or not.
I'd get another quote though rather than rely solely on the electrician(s) that have said your wiring is illegal.

Vortigern · Feb 25, 2023

Sounds reasonable to me but then it would if I could get that price for a rewire. Check insurance and scheme membership before employing any electrician. In the South West where I am a four bed house with decent re-wire spec....6-8k is ball park. London 10-12k up North 2k.

Dustydazzler · Feb 25, 2023

First things First does the old wiring really new Re-Wiring

If its all needs re-wiring for example is old imperial cable or no cpc on lighting then £17K for a re-wire and new wiring of extension seems reasonable to me

But a job of this scope I would get ATLEAST 3 quotes maybe even 4 quotes

7029 dave · Feb 25, 2023

As suggested some pictures of the CU area would be good, to get a gauge of the age of the installation etc.
IMO pvc cable twin & earth is bullet proof in general.

Dave OCD · Feb 25, 2023

I wonder if this person quoting in under the impression that the older red/black wiring is in some way unacceptable ? If so I'm afraid you're dealing with an idiot.

MJPD29 · Feb 25, 2023

Dave OCD said:
I wonder if this person quoting in under the impression that the older red/black wiring is in some way unacceptable ? If so I'm afraid you're dealing with an idiot.

Come on Dave we all know red and black wiring is illegal in todays society

Dustydazzler · Feb 25, 2023

I still use red and black every now and then on proper posh alterations where I want to keep the colours as per the original install

pirate · Feb 25, 2023

Me too! Or where i simply want to disguise my interventions!
Still got plenty red/black drums of cable in my garage...

pirate · Feb 25, 2023

and some twin red...
always handy to have

littlespark · Feb 25, 2023

Red and black is pre 2007, unless you’re Dusty….

Not a valid reason for a rewire, there’s 50 year old red and black in perfectly good condition.

If there was a serious issue at the time of the CU change, it would have been documented at the time or fixed…..

The current electrician is trying it on in my opinion…. But of course, we’re not there, so we don’t know what’s he’s seen.

James · Feb 25, 2023

Has this electrician actually provided you with a report telling you why the installation is unsatisfactory?

Surrey House Renovator · Feb 26, 2023

If there is work to be done and the house is unoccupied then get it done whilst it’s empty. Shop around.
If you do a new consumer unit most will advise on breakers that are more sensitive eg rcbo rather than mob . There is always a chance further work will need to be done when sensitive breakers trip. But then you would want to know of any issues ???
A bit of extra capacity on the cu is always desirable

Midwest · Feb 26, 2023

17k sounds a bit steep to me, less it’s a Trump palace and spec, in the middle of London.

Dustydazzler · Feb 26, 2023

Midwest said:
17k sounds a bit steep to me, less it’s a Trump palace and spec, in the middle of London.

Middle of London £17k would barely get you a 1 bed flat Re-wire these days, some of the prices I see banded about this year are eye watering. You only have to look at what Artisan are charging £800 per day + Vat for Re-wire work and that is in Cambridge.

pc1966 · Feb 26, 2023

Dustydazzler said:
You only have to look at what Artisan are charging £800 per day + Vat for Re-wire work and that is in Cambridge.

Clearly I'm in the wrong job!

7029 dave · Feb 26, 2023

I would happily mate for £200 a day long as I get me hour for lunch lol

Risteard · Feb 26, 2023

7029 dave said:
I would happily mate for £200 a day long as I get me hour for lunch lol

I believe there is a specific job title for people who mate for money ;-)

7029 dave · Feb 26, 2023

Risteard said:
I believe there is a specific job title for people who mate for money ;-)

Electric stud eh

Intoelectrics · Feb 27, 2023

My advice, get a proper report done on the existing then get quotes in for any works that are required and any works you would like doing. Always best to get the jobs done whilst unoccupied and during alterations, before decorating, final fixtures and fittings.

Depending on what is required based on the report and what is required by yourself for alterations/additions it may prove more economical to start again. However until you get a proper report done then you are in no real position to know what is the best course of action.

If you get a report done, please feel free to share with us the results.

timhoward · Feb 28, 2023

I completely agree with @Intoelectrics, Looking at the results from 2 years ago I'd be surprised if a rewire was warranted but only a decent EICR will tell you.
My top concern from the last testing is that circuit 4 is getting close to being too long (Zs of 1.04 ohms sitting on a B32). It wouldn't be sensible to extend that circuit.

Acca dacca · Feb 28, 2023

timhoward said:
I completely agree with @Intoelectrics, Looking at the results from 2 years ago I'd be surprised if a rewire was warranted but only a decent EICR will tell you.
My top concern from the last testing is that circuit 4 is getting close to being too long (Zs of 1.04 ohms sitting on a B32). It wouldn't be sensible to extend that circuit.

Hmmm maybe a spur on a spur in the ring, or is the house that big that you would have a circuit length of 50+ metres on 2.5/1.5 T&E?

timhoward · Feb 28, 2023

Acca dacca said:
Hmmm maybe a spur on a spur in the ring, or is the house that big that you would have a circuit length of 50+ metres on 2.5/1.5 T&E?

You forgot to take off the Ze (0.36 in this case). So we're talking about 0.67 ohms worth of actual circuit, so more like 28m of cable which is plausible for a ring final circuit that covers more than one floor.

Acca dacca · Mar 1, 2023

timhoward said:
You forgot to take off the Ze (0.36 in this case). So we're talking about 0.67 ohms worth of actual circuit, so more like 28m of cable which is plausible for a ring final circuit that covers more than one floor.

Ah yes my bad! Although interesting on the schedule of results the figure 0.36 is recorded as the Zs? and Not Ze....And the Ipf is quoted as 1.06kA?

timhoward · Mar 1, 2023

Acca dacca said:
Ah yes my bad! Although interesting on the schedule of results the figure 0.36 is recorded as the Zs? and Not Ze....And the Ipf is quoted as 1.06kA?

On the 1st page it gives 0.36 as the Ze (twice in fact!). I can't spot where you mean for 0.36 Zs.

The confusion over the 1.06Ka is because the property has TNS earthing. As your profile says you are a trainee I'll elaborate a bit....(hang in there!)

The Ipf is the highest of prospective dead shorts of Live-Earth and Live-Neutral and as this property has TNS earthing the two will differ due to the different sizes of the two cables all the way back to the substation transformer. (If it were TNCS earthing then due to the neutral-earth link in the cut-out the values would be the same)

The path back to the transformer through the neutral has a lower impedance of 0.21 ohms (working backwards from 1060 amps) as it's a bigger wire. This makes sense.
So the maximum fault current Line-Earth is 638 amps (230/0.36) and the maximum fault current Line-Neutral is 1060A.
The installer recorded the higher of the two (correctly).

Acca dacca · Mar 1, 2023

timhoward said:
On the 1st page it gives 0.36 as the Ze (twice in fact!). I can't spot where you mean for 0.36 Zs.

The confusion over the 1.06Ka is because the property has TNS earthing. As your profile says you are a trainee I'll elaborate a bit....(hang in there!)

The Ipf is the highest of prospective dead shorts of Live-Earth and Live-Neutral and as this property has TNS earthing the two will differ due to the different sizes of the two cables all the way back to the substation transformer. (If it were TNCS earthing then due to the neutral-earth link in the cut-out the values would be the same)

The path back to the transformer through the neutral has a lower impedance of 0.21 ohms (working backwards from 1060 amps) as it's a bigger wire. This makes sense.
So the maximum fault current Line-Earth is 638 amps (230/0.36) and the maximum fault current Line-Neutral is 1060A.
The installer recorded the higher of the two (correctly).

Im referring to the additional images further along the thread, if you look at image marked cert4 that's where the Zs figure of 0.36 in the 2nd box is. Thanks for pointing the TNS earthing arrangement out, in my haste I neglected to notice that, perhaps ive miscalculated something along here but i made the mistake/error of calculating (230/1.04) 1.04 being calculated on the circuit #4 for the R1+R2+Ze, if that clarifies/muddy's the water..