Domestic Electric Supply Cable question....

[Christian and Beccy]

I'm currently arguing with my local DNO about moving of my Electric Meter. They initially said they could run my supply cable from the pole, to a bracket on the gable end and then into the loft via a 20mm access hole. From here, the cable would enter their regulation 32mm Smooth Duct where it would pass briefly through the loft before diving down the cavity to the External Meter Box, remaining inside the 32mm ducting until it arrives at the Meter Box.

They are now saying that they don't like the idea of the duct going into the void because it can't be seen. They would prefer it to be underground, but my point is that it can't be seen there either!

The cable is much safer using my method than what they are proposing. They want to come from the bracket, down the gable end to ground level, then around the bungalow underground before coming back up the wall in a hockey-stick.

I just want to know whether whatever regs they are covered by prevent the cable/duct going in the cavity? I know the unsupported cable can't go in the cavity, but surely in the ducting it's OK?

 

[securespark]

Our regs are different to theirs.

You need to talk to westie.

WESTIE!!

 

[ricicle]

I think most DNOs are trying to do away with their cables/equipment being anywhere inside a domestic property. That's why it's all external meter boxes now and not boards in cupboards under the stairs !

 

[Christian and Beccy]

Oddly, they are happy to allow me to keep the meter indoors and in which case the cable can come in through the loft. It's only because I want it external that this problem has arisen.

I get sick of pushy meter readers, I submit my meter readings every month on the 1st of the month without fail, but still they want to come and hound me for access. I digress!

The guy I'm dealing with is not a very 'straight down the line' kind of guy, it's all if's, but's and maybe's. I want to know the line of the law. If it's not allowed to be in ducting in the cavity, I'd prefer to see where that's documented, then I'll let it go.

The existing cable is long enough if it's to be done my way. If they want to come down the wall and halfway round the outside of my property, it means a whole new piece of cable too.

Thanks for your help so far.

 

[bernardgreen]

Underground is safer as the cable is supported all the way and not hanging supporting its own weight. Installed underground it will be deep enough to not be at risk from digging. A marker tape above the duct will prevent all but the most careless excavator from hitting it.

The other advantage of going underground are roof repairs in the future can be carried out without involving the DNO and strong winds / falling trees etc will not be ripping the supply cable off the building.

 

[Christian and Beccy]

To clarify, I'm not interested in putting the whole length of the supply cable underground, that's going to cost about £1200. (their costs are £900, plus excavation costs and ducting etc).

I know it would be nicer in so many ways, but we're talking £800-900 difference between the 2 jobs and there's isn't enough of a benefit to justify it in my mind. Besides which, even with my cable underground, the pole is virtually in my garden and I see the set of 4 cables shooting off in 3 directions, so it's not even about aesthetics.

The Meter Box really needs to go on the side elevation, so they want to bring it from that point to underground, then around the perimeter of the bungalow (where we will encounter various drainage runs, soakaways, paths etc.

They are happy for the cable to be in the ducting, in the loft, but it's the last 1.0-1.5 metres where it disappears into the cavity down to the Meter Box (and is literally only that much) that they have queried.

They are investigating whether or not it can be done, but I'm trying to find the truth on it (hopefully).

 

[westie101]

Nowhere publicly is it documented that the cable cannot go down the cavity in a pipe.
However it will probably be documented in that form in an internal DNO document, in all honesty this type of routing we did away with over 40 years ago owing to the hazards that are introduced by its presence.

There will be a cable in place that the house owner (you) will have no control over.

It will be protected at a substation by a fuse of between, probably, 200 and 400 amps. If it develops a fault it is unlikely that this fuse will operate, but the cable could start burning back - once it reached the loft the big probability of a destructive fire is the result. We do have some like this and strive, every time we find one to remove it from this sort of situation)

As it will have no mechanical protection if it is drilled into inadvertently as it's presence may not be realised, that has a potential for serious injury.
(if it is buried it will have a marker tape to indicate it's location, I doubt you would like marker tape stuck to your walls to show it is there) Also it will be shown on the DNO cable location plans which should be consulted before any excavation in any location.

Within the cavity for any distance increasing the risk of bridging the cavity and introducing damp to the property.

Whilst advice does vary between DNOs the one I work for would absolutely not consider the loft/cavity solution

 

[sparkwright]

I'm starting to think for the sake of £900, you'd be better off with the whole length of the cable in the ground...

 

[bernardgreen]

If you arrange to dig the trench your self it will be a big saving. Even if you hire a local chap with a mini JCB it will be cheaper than the DNO cost for the same work. You dig the trench, lay in a 32 mm duct and back fill. Take photos with clear indication showing the trench is 450mm or more deep.

That is based on my experience of installing a new supply to the cottage I am renovating.

 

[Christian and Beccy]

The £900 is for them to pass the cable down the duct that I lay. It's with me doing everything I can do (fitting the new meter box, hockey sticks both ends etc.). I'd hazard a guess that it is largely made up by the cost of replacing the whole length of cable?

It's about 20 metres directly across the middle of my garden, so on top of the cost of digging the trench (I'd handball it if I had to, but I'd expect to pay circa £150-200 to get someone in with a mini-digger), there's the cost of making good the garden afterwards, we all know it's unlikely that it can be returned to it's original state quickly/easily. I know that the main drainage runs perpendicular to where the new trench would need to be dug, so we'll encounter that at some point I'm sure. There's also a Plum tree, the roots of which are likely to be in the way. Besides, I've got a sh***y area in the garden where all the excess building materials from our extension are currently stored in preparation for the Garage to be built, but that's not for 1-2 years. Typically, this is all in the way!

I can see the point about the cable hazard, but the vulnerable part of the wall is the small section between the top of the meter box and the soffit. Surely anyone with an ounce of sense would avoid drilling/fixing in the vicinity of the meter box without first checking the cable positions anyway? On top of that, what are the chances of needed to drill beyond the 4" block-work?

I don't know, it's just very tedious. The bungalow was built in 1929 and the cable has existed happily in it's current state of vulnerability for years and years. Surely there's some degree of risk by it being overhead in any case? But still the majority of supply cables are!

 

[flyingsparks]

Surely anyone with an ounce of sense.... [\quote]

There's not much of that around these days...

 

[Christian and Beccy]

Surely anyone with an ounce of sense.... [\quote]

There's not much of that around these days...

I suppose you're right there!

 

[bernardgreen]

The £ 900 will be payment for the work of connecting the cable to the existing supply while still live and the supply and fitting of the new cut out. The cable cost is minimal compared to the labour and insurance costs to the DNO. I would expect the cost would not be much less for running it how you want it.

Westie has explained the serious hazard of the supply cable running through the loft. It is effectively unfused ( it will burn for many minutes before the 200 amp at the sub station blows, if it ever does blow ). The cable could be damaged in the loft by something heavy stored up there, or rodent damage.

Having seen the damage from a burning supply cable I would never accept an unfused supply cable running through my building.

 

[Christian and Beccy]

The £ 900 will be payment for the work of connecting the cable to the existing supply while still live and the supply and fitting of the new cut out. The cable cost is minimal compared to the labour and insurance costs to the DNO. I would expect the cost would not be much less for running it how you want it.

Westie has explained the serious hazard of the supply cable running through the loft. It is effectively unfused ( it will burn for many minutes before the 200 amp at the sub station blows, if it ever does blow ). The cable could be damaged in the loft by something heavy stored up there, or rodent damage.

Having seen the damage from a burning supply cable I would never accept an unfused supply cable running through my building.

Bernard, they've actually quoted for doing it my way, or similarly. It's approximately £250. Seriously, and that includes isolation at the pole. It's at the 'final hour' that they've decided they aren't completely happy. Furthermore, they are happy to put it in the loft, providing it's in their 32mm duct. It's a logical approach. So, on that basis, if they are happy for it to run in a piece of 32mm duct inside the loft space, why not for the last little bit down the cavity?!

As I've said before, I know it's not the ideal solution, but there is more than one way to skin a cat as they say. Ideally we'd all have our cars serviced by main dealers, but many of us have to look at alternatives. This is a similar situation. If it was an extra £100-200, it'd be a no-brainer. It's about 400% more expensive!

 

[ban-all-sheds]

But ATEOD, it's their cable and their service - if they won't run it in the cavity, then they won't run it in the cavity, and that's it, no matter how unreasonable you, or anybody else here, thinks that is.