Flat Supply - Dubious earths?

[GeeTee]

I'm in the process of moving into a flat (1920s purpose built block) that's been unoccupied for a few years and thought I'd take a nose around the electrics today. I have a horrible feeling there is no effective earth to the flat.

The DNO supply enters the building under the stairs, there's two heads serving 3 flats each. From the head the cable (red 1) goes to the meter, from the meter there are two blacks (labelled 2 and 3) and a red (labelled 4) that run off to some wired off boxes (presumably supplier fuses). From there a fabric sleeved pair runs off to a chunky cutoff switch.

Pics (my flat supply is the key meter in the middle):

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• GeeTee
• 31 Aug 2013
• 1

And the chunky cutoff:

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• GeeTee
• 31 Aug 2013
• 1

So my first concern is there is nothing connected to the earthing block next to this head that serves my flat and 2 others. Whereas on the other head, there are a couple of runs of unsheathed silver cable running from the corresponding earth block and the outside of two of those flats' chunky cutouts.

Pics:

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• GeeTee
• 31 Aug 2013
• 1

So moving inside to where the supply enters the actual flat. The earth from the block heading right goes to the fuse box. The black wire links the block and the metal conduit containing the incoming supply. However the conduit is really rusty, so I find it hard to believe it is serving any purpose:

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• GeeTee
• 31 Aug 2013
• 1

A couple of wider shots of the area:

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• GeeTee
• 31 Aug 2013
• 1

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• GeeTee
• 31 Aug 2013
• 1

I've no idea where that shower feed is taking its supply from but I think the white cable out the top is what runs over to the bathroom.

Fuseways (if it's of any relevance) from right to left:
- Lights
- Socket Ring
- Immersion Heater
- 2 Single sockets in kitchen (that's how it's labelled, although there is 3 singles and a double in there)

Oh and one last piece of horror for your delight - what I think is meant to be bonding to the water main. The steel pipe is the rising main for the block, the copper sections serve the flat. Note how snugly the earth band is attached!

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• GeeTee
• 31 Aug 2013
• 1

I have left ~everything~ switched off! It just does not look at all safe to me, but I could be wrong and it's all perfectly normal

Any thoughts?

 

[RF Lighting]

Have you bought or rented this flat?

It just looks old, rather than bodged etc.

The switch downstairs in picture 2 & 3 belongs to you, as does all of the installation after this point.

It is a switch fuse, and is there to protect the cables from this point to your flat.

I think there is an effective earth, albeit undersized, but in reality as the submains is VIR in conduit, it is well overdue for replacement.

The best course of action is to employ an electrician to carry out an EICR for you, which will give you a report of wha condition the installation is really in, but be prepared for some if not all of the wiring to require replacement.

 

[OwainDIYer]

The rubber cables through timber and ironclad switchfuse assembly is a fire waiting to happen and if that's under the stairs i.e. your communal escape route then your freeholder/managing agent has some serious responsibilities under the Fire Safety (Regulatory Reform) Order.

I wouldn't bother with an EICR - it needs rewiring right back to the meter, and preferably the supplier to provide a PME earth connection.

The flat will need rewiring as well as what is there will be completely inadequate. If any of the existing cabling happens to be convenient and in good order it might be reused but that would be an unexpected bonus.

 

[RF Lighting]

That seems quite a brash statement on the evidence of a couple of out of focus photos!

 

[GeeTee]

Have you bought or rented this flat?

It just looks old, rather than bodged etc.

The switch downstairs in picture 2 & 3 belongs to you, as does all of the installation after this point.

It is a switch fuse, and is there to protect the cables from this point to your flat.

I think there is an effective earth, albeit undersized, but in reality as the submains is VIR in conduit, it is well overdue for replacement.

The best course of action is to employ an electrician to carry out an EICR for you, which will give you a report of wha condition the installation is really in, but be prepared for some if not all of the wiring to require replacement.

I own the flat (it's leasehold).

So the chunky cutoff switch under the stairs is the demarcation between the DNO and my responsibility?

To replace the run from there to the flat would likely be disruptive to the communal areas of the block (the hall), I guess I'll have to involve the freeholder or maintenance co. if that is required.

So the conduit forms the earth on the submain? How is the conduit earthed, as it does not run all the way back to the chunky switch under the stairs?

The internal wiring inside the flat seems mixed - grey pvc sheathed to kitchen and immersion, white pvc to lights and socket ring. A partial rewire at some point perhaps. I took a look behind a couple of switches and it looks like the internal wiring was also run in conduit originally.

 

[Iggifer]

Yea the T+E underneath the CU doesnt look ancient

 

[GeeTee]

The rubber cables through timber and ironclad switchfuse assembly is a fire waiting to happen and if that's under the stairs i.e. your communal escape route then your freeholder/managing agent has some serious responsibilities under the Fire Safety (Regulatory Reform) Order.

I wouldn't bother with an EICR - it needs rewiring right back to the meter, and preferably the supplier to provide a PME earth connection.

The flat will need rewiring as well as what is there will be completely inadequate. If any of the existing cabling happens to be convenient and in good order it might be reused but that would be an unexpected bonus.

Thanks for your concern. The meters and cutouts are under the stairs. The cables from the supplier heads to the meters and the wired up box things (fuses at a guess) all looks fairly new and seems to be PVC. Beyond that though it's a real mish-mash of cable types run to and from each flat's cutout.

As for the fire risk - I'll take a look into that Order you mention. The stairs are concrete, as are the ceilings / floors between flats. Being on the ground floor I have additional exits via two front patio style doors then over hip high 'balcony' wall, a back door to the rear garden and at a push I could squeeze out the back bedroom's window. That's me covered I think As for the two flats above me, as well as the internal stairs there is an external metal fire escape serving the rear of the block.

 

[westie101]

and preferably the supplier to provide a PME earth connection.

I've said this before and will continue to say it

No No No NO

The correct statement should be: -
The DNO to supply an earth connection! There is NOTHING wrong with a TNS earth and no magic to a PME (TNCS) connection.

For us to supply a PME earth on that supply would cost a huge amount, for a TNS nothing!

 

[Iggifer]

I have TNCS and my Ze is great

 

[RF Lighting]

It's hard to see from the photos, but the DNO appears to already supply an earth. It seems to be the consumers earth which is inadequate.

 

[RF Lighting]

I have TNCS and my Ze is great

I have a TN-S supply and my Ze is great. What's your point?

 

[westie101]

I have TNCS and my Ze is great

Good for you

 

[JohnW2]

For us to supply a PME earth on that supply would cost a huge amount, for a TNS nothing!

You sound confident, westie - what makes you think (or be fairly sure of) that?

Kind Regards John

 

[westie101]

what makes you think (or be fairly sure of) that?

It is the two words "For us"

I know my employers policy and procedures and what is required on the type of incoming cable shown to supply a PME earth.

 

[GeeTee]

It's hard to see from the photos, but the DNO appears to already supply an earth. It seems to be the consumers earth which is inadequate.

Apologies for the rubbish photos, I only had my ancient nokia with me and those pics of the understairs were getting sun on them hence the weird flares all over them.

Yes, there is an 8 or 10 way earth block down by the DNO service head. None of the 3 flats have anything connected back to it - it's empty other than the cable from the head.

That being the case... how can any of the flats have an earth? Is the conduit somehow tied directly into the ground somewhere?