How bad is this house wiring?

[glock339]

I was round my dads house yesterday to do a couple of jobs & noticed a card on top of his gas meter (he had smart meters fitted aprox 4 years ago) warning there was no earth bonding. This rang some alarm bells, unfortunately my old dad couldn't remember anything about this so I decided to try & find out what was going on.

Long story short version of what I found after poking around:

Distribution board is a complete mess, no RCD protection, no sleeves on earths, looks a shambles etc & apparently was done around 40 years ago.

Almost crapped my pants when I saw there was no earth from the supply sheath to the DB, although I could see a cable coming off the sheath & going under the floor. After checking for continuity with a cheap hobby meter he had lying around & some long wire I found I got continuity between the sheath bonding & the DB earth bar so I assume the earth cable I could see going under the floor connects to the water bonding & gas bonding then connects from the gas bonding to the DB earth bar rather than just fitting an earth from the incoming supply to the DB which is directly above it

How worried should I be about the state of his electrics & what would be the recommended course of action? I have a feeling a full re-wire will be recommended but convincing my old dad to get one done would be another matter altogether.

 

[Murdochcat]

I hope you have the cover to the consumer unit.

Get a local spark to do a proper EICR and go from there

 

[ericmark]

It looks as if some one took an adaptable box and made in into a distribution unit, it seems likely it is TT as the earth terminal provided has not been used to make it TN.

TT must have a RCD/RCBO/ELCB some where, but I can't see it, TT is not all bad, however my parents house wired 1954 must have had the water pipes acting as earth, in 2004 I could find no earth, and converted it to TN-C-S.

To correct it will cost, either LABC fees or scheme member electrician mean your looking at over £500 to correct what you have, actual cost depends what needs doing, when a new consumer unit was fitted to this house I found borrowed neutrals, and one must expect some remedial work being required.

The suggested route is an EICR to find out what needs doing, then getting it done, I actually did it the other way around as what ever the bill was it was going to be done, so consumer unit fitted then find the faults. But I had the skill and equipment to find the faults and correct them.

Note a consumer unit is a type tested distribution unit, and old houses have fuse boxes and distribution units built before the type testing was done so are distribution units. I am sure some one will say why we can't use distribution units in domestic, but it will be easy enough to change as you already have an isolator so you can turn off the power to do the work.

The electrician before starting will use one of these to work out if you can use a group of MCB's on one RCD, and one of these to work out is cables are OK and cheapest I can find is £35 each, then he will use more expensive meters to measure loop impedance and RCBO tripping times, so to DIY will cost nearly the same as using a scheme member by time you buy the test gear and pay the LABC fees, so not really worth doing as DIY.

 

[EFLImpudence]

That is not actually correct.

It is the entering external gas and water pipes which must be connected to the installation's earth terminal.

 

[stem]

My mum had several similar notices over the years, but the bonding was actually present.

The gas supply pipe entered the hallway of her bungalow from an external meter box, and ran straight up the wall into the roof space above. In front of the pipe at the point of entry where the clamp was attached was a hanging rail for coats, so the coats hid the pipe from view. No one thought to look at the point of entry which was fairly obvious from the location of the meter box, and just instead a notice instead.

Just saying. It might be worth having a look around.

 

[glock339]

It looks as if some one took an adaptable box and made in into a distribution unit, it seems likely it is TT as the earth terminal provided has not been used to make it TN.

TT must have a RCD/RCBO/ELCB some where, but I can't see it, TT is not all bad, however my parents house wired 1954 must have had the water pipes acting as earth, in 2004 I could find no earth, and converted it to TN-C-S.

To correct it will cost, either LABC fees or scheme member electrician mean your looking at over £500 to correct what you have, actual cost depends what needs doing, when a new consumer unit was fitted to this house I found borrowed neutrals, and one must expect some remedial work being required.

The suggested route is an EICR to find out what needs doing, then getting it done, I actually did it the other way around as what ever the bill was it was going to be done, so consumer unit fitted then find the faults. But I had the skill and equipment to find the faults and correct them.

Note a consumer unit is a type tested distribution unit, and old houses have fuse boxes and distribution units built before the type testing was done so are distribution units. I am sure some one will say why we can't use distribution units in domestic, but it will be easy enough to change as you already have an isolator so you can turn off the power to do the work.

The electrician before starting will use one of these View attachment 326100 to work out if you can use a group of MCB's on one RCD, and one of these View attachment 326101to work out is cables are OK and cheapest I can find is £35 each, then he will use more expensive meters to measure loop impedance and RCBO tripping times, so to DIY will cost nearly the same as using a scheme member by time you buy the test gear and pay the LABC fees, so not really worth doing as DIY.

I couldn't tell you if there's an earth rod under the floors. As I say I did find continuity between the earth bar & the sheath bonding do I'd guess the earth goes from the sheath, under the floors to the water bonding, then to the gas bonding before going to the boards earth bar but that's about as much as I can tell from what's accessible. I bumped into to a spark I know yesterday & briefly quizzed him about the situation & he said he'd seen some similar old setups to this on jobs he'd done around here that needed sorting out.

Some great info there thanks, taking the time. The main problem I'd have is to convince my dad to get it looked at as I think he knows it's not an easy fix & he's at that point where he just doesn't want any fuss. Will have to have a think.

 

[ebee]

It is the entering external gas and water pipes which must be connected to the installation's earth terminal.

Well if it is external then entering to become internal it is the same short length of pipe any way.
Do you think of a "point of entry" to be on the outside comming in or on the inside comming thru the wall?

I see either as "point of entry" and see in this case "internal" and "external" having the same understood meaning.
I suppose if we changed it all to "somewhere near where the pipework is in the property from outside/thru the ground" we might be agreed and providing the connection is durable and reasonably protected from accidental or criminal damage then it should be OK?

Personally I always install just on the internal bit (or within 600mm or thereabouts and before any branches or tees if possible) but I`d not chastise anyone who makes it a meter or three further away.

 

[ebee]

I couldn't tell you if there's an earth rod under the floors. As I say I did find continuity between the earth bar & the sheath bonding do I'd guess the earth goes from the sheath, under the floors to the water bonding, then to the gas bonding before going to the boards earth bar but that's about as much as I can tell from what's accessible. I bumped into to a spark I know yesterday & briefly quizzed him about the situation & he said he'd seen some similar old setups to this on jobs he'd done around here that needed sorting out.

Some great info there thanks, taking the time. The main problem I'd have is to convince my dad to get it looked at as I think he knows it's not an easy fix & he's at that point where he just doesn't want any fuss. Will have to have a think.

Yes that is not unusual but good look with your thinking, obviously you want to make your Dad safe or at least safer than he is now, not always easy

 

[glock339]

My mum had several similar notices over the years, but the bonding was actually present.

The gas supply pipe entered the hallway of her bungalow from an external meter box, and ran straight up the wall into the roof space above. In front of the pipe at the point of entry where the clamp was attached was a hanging rail for coats, so the coats hid the pipe from view. No one thought to look at the point of entry which was fairly obvious from the location of the meter box, and just instead a notice instead.

Just saying. It might be worth having a look around.

I've had a good look around in (all the accessible areas anyway) & as I say it looks like the earthing goes from the supply sheath, to under the floor, to the water bonding, then to the gas bonding, then to the boards earth bar. No idea why they wouldn't just go from the supply sheath to the earth bar, which only about a metre & a half away & has boxing connecting the 2 for the tails. Speaking of the cable that connects the main fuse to the box it appears to be some sort of twin & earth rather than separates which I'd not seen done before & the original spark has just cut the unsheathed earth between the L&N at the point where they're expose.

 

[ebee]

so consumer unit fitted then find the faults.

Cart, horse, before!

 

[ericmark]

Cart, horse, before!

Maybe but I am not a scheme member, so needed a scheme member to change the consumer unit, but I am an electrician so I could correct any errors found when changed, there was only one fault found, wrong neutral used in one 4 gang light switch.

I know I have before Part P came in put an earth rod in under the floor boards, a town house with no where outside it could go, so no option. The only real way is to use a loop impedance tester and see what the reading is for the earth loop impedance, we would normally expect around the 60 Ω mark, but up to 200 Ω is acceptable (assuming RCD's fitted) above that still comes within the limits but is considered as unreliable. When any work is done, there should be a installation or minor works certificate raised. When I had solar panels fitted I got this.

As part of the paperwork, I will admit it does not seem to make sense 230/840 = 0.27 Ω but not sure if that was with our without the DNO supply connected, I will assume with as TN-C-S is ticked, and without the DNO it would be TN-S, but this is an unusual case as can run from battery as well as grid supply. But if you have had any work done you should have a similar bit of paperwork, in my case emailed as a PDF. This should show what the earth is and how good.

 

[ebee]

Better to test then correct, if needed, any errors I`d say Eric

 

[SimonH2]

Speaking of the cable that connects the main fuse to the box it appears to be some sort of twin & earth rather than separates which I'd not seen done before & the original spark has just cut the unsheathed earth between the L&N at the point where they're expose.

Using T&E is OK with some caveats - and it's common if there's some distance between items.
Seeing as this is on the supply side of the meter it's not your responsibility and the rules are a bit different. Where it falls down is that at the service head (supplier's fuse) and meter, there's no enclosure to cover the single insulated cores where the sheath is stripped back - the core insulation shouldn't be visible like that. I suspect the meter fitter broke multiple rules by leaving the installation in that state. I expect there exist suitable heat-shrink solutions similar to what DNOs use with concentric cables.
As to hidden bonding, in our rental flat the gas bonding is behind the fridge in the kitchen where the pipe comes in from the meter box. The second EICR I had done (we've had itva long time) this got flagged up as I'd forgotten and it was hidden behind the fridge. The first EICR was OK as there was no fridge so it was visible.
Apart from that, what others have said - get an electrician to take a look and go from there. It's helpful here if you know someone you can trust since there are so many charlatans who see EICRs as an opportunity to fleece customers on vaguely described safety remediation work.

 

[ericmark]

The main problem I'd have is to convince my dad to get it looked at as I think he knows it's not an easy fix & he's at that point where he just doesn't want any fuss.

I had the same problem, I knew the house had rubber cables, wired 1954, and it needed a rewire, dad said "I am not living in a building site, you can rewire it when I'm gone." which is what happened, the cables were crumbling by time I got it rewired.

But a new consumer unit is done in a day in most cases, it is not a full rewire, likely an EICR is the way to go, as if it says something wrong, you have some thing to try and persuade him with. I did get a new consumer unit fitted, which was like you already have, as the electrician fitting it could not get the RCD to hold in, he was not really a good electrician as he used the GPO party line earth rod and cables as his main earth so 1 mm bare earth cable on a TT supply, I got house on a TN-C-S supply.

So what greave will I give my son, will I stop him upgrading my house in the same way, now 72 so he looks at me as being an old man. I know I have all type AC RCBO's will he want me to change them for type A? I have no RCD protection on my central heating supply, will he want that changing? I have a compliant certificate less than a year old which says it's OK.

 

[ebee]

I do not think you old Eric.
Mid you I am biased.
when I was 10 I might have thought as you being old back then.
Ten years later I might have thought of you as very slightly old.
Now at 68 I dont really think you old at all!
when we were 35 I declared we were middle aged and S W M B O slated me for it.
I stated a famous book that I believe states our alloted time is three score and ten then 35 is half that = middle = middle aged but I still got chastised.