New supply from transformer mast for 9 separate metres property connections?

[D Skelton]

To comply with the volt drop requirements at 150m then you would need to be limited to 25A to use 25mm² SWA.

This would allow for no VD at all on any of the final circuits RB

 

[Richard Knight]

Wrong forum, but have you got the costs for New Water supplies?

And Foul drainage connections or is it Biodigestor?

We paid £3000.00 to the development site owner, this was to lay down and connect us into the mains water supply and the electrical mast available on site.

Can of worms... The water supply had issues, there wasn't enough pressure to supply the lodge plots at peek demand times. This has been rectified for other plot owners using a large break tank and pumps... we didn't buy into the system. The development owner wanted another £1200.00 for this. So we have decided to have our own holding tank in the property.

We bought the plot with SEPA consulted and agreed systems...

The system we are going for is a domestic sewage treatment plant, this removes 95% of bacteria where as a septic tank removes just 10% (if I remember correctly those figures are accurate)

All plots have passed percolation tests, apart from ours - the day ours was done the area got record rainfall so was't a fair test. The development owner has paid for all test for other plots... but he is refusing to pay for our re-test. Looks like that will be another £1200.00 for a SEPA consultant to test it and design the system.

Self-building is bloody expensive and stressful! But also very exciting, I hope it's worth it in the end!

 

[Engineer54]

All of which is WHY i asked about the distances involved questions above!! ...lol!!

The other question that should be asked, is how are you (OP) intending to run these supply cables to each plot?? Without knowing the layout, the distances may well need to be in excess of what your planning. Eg, are these cable routes following paths/road or as the crow fly's, crossing the other plots underground?? If the latter, you may need to go deeper than the recommended 600mm (60cm) and be run in heavy duty ducting....

 

[Richard Knight]

Here is the cable calculation for 10mm cable at 150m - he intimated it would give 25 amps at 5% VD.

The above doesn't make much sense to me.

 

[Richard Knight]

All of which is WHY i asked about the distances involved questions above!! ...lol!!

The other question that should be asked, is how are you (OP) intending to run these supply cables to each plot?? Without knowing the layout, the distances may well need to be in excess of what your planning. Eg, are these cable routes following paths/road or as the crow fly's, crossing the other plots underground?? If the latter, you may need to go deeper than the recommended 600mm (60cm) and be run in heavy duty ducting....

I'm not laying any cable for anyone else... just our own plot.

There is a 10mm cable laid in at the moment, which isn't of any use to us - maybe a temporary supply for plugging in tools - that would be useful and save on petrol with the generator! Max load would be 25 amps as suggested by the engineer and calculations above.

Not crossing any plots, following the road. It has been measured countless times. 115m to the edge of the plot, then another 30m to the entry point in the dwelling.

 

[D Skelton]

View attachment 24708

Here is the cable calculation for 10mm cable at 150m - he intimated it would give 25 amps at 5% VD.

The above doesn't make much sense to me.

I don't know much about his design software, but if that's what he's saying then he's wrong I'm afraid, very wrong!

On a 10mm three core thermosetting SWA, 25A over 150m results in a voltage drop of 17.6V, or 7.6%, 2.6% over the maximum allowed for general circuits according to the guidance given in appendix 4 of BS 7671.

 

[Richard Knight]

I don't know much about his design software, but if that's what he's saying then he's wrong I'm afraid, very wrong!

On a 10mm three core thermosetting SWA, 25A over 150m results in a voltage drop of 17.6V, or 7.6%, 2.6% over the maximum allowed for general circuits according to the guidance given in appendix 4 of BS 7671.

Thank you for bringing this to our attention!

 

[D Skelton]

Having looked closer at that picture, I've so far counted what appear to be at least 9 glaring errors with the software?!

Is anyone else in a position to confirm or dispute?

 

[Knobhead]

Is this a wind up? It was Friday yesterday.
For someone to buy a plot of land with such obvious problems beggars belief.

As for this being a self-build, it has all the hallmarks of a disaster epic. Lots of money sinking without trace.

 

[Richard Knight]

Is this a wind up? It was Friday yesterday.
For someone to buy a plot of land with such obvious problems beggars belief.

As for this being a self-build, it has all the hallmarks of a disaster epic. Lots of money sinking without trace.

No wind up... what's Friday got to do with it, have no idea what your'e talking about! When my parents bought the land they were naive! They put trust in a NHBC housing developer (who is selling the plots) and the solicitors who dealt with paperwork. Lesson learnt for them, they wont make that mistake again if they buy development land in the future.

I will be glad when the services are sorted, everything else is fully in our control regarding building works. My parents have experience of multi-million pounds worth of building projects.

 

[Knobhead]

Given the problems with the electricity, water and sewage I would suggest you employ a project manager that knows what he is doing.
Your comment “I’m not running cables for others” is incredibly short sighted. As for your plot having its own potable water and sewage arrangement is bordering on stupidity.

You would seem to have alienated yourself from the other owners and now you’re going to pay for it.
But as it’s your money, do as you will.

I assume you are paying this supposed “engineer” for his services, I find it somewhat offensive that you come here expecting total strangers to assist for nothing.

 

[Richard Knight]

Given the problems with the electricity, water and sewage I would suggest you employ a project manager that knows what he is doing.
Your comment “I’m not running cables for others” is incredibly short sighted. As for your plot having its own potable water and sewage arrangement is bordering on stupidity.

You would seem to have alienated yourself from the other owners and now you’re going to pay for it.
But as it’s your money, do as you will.

I assume you are paying this supposed “engineer” for his services, I find it somewhat offensive that you come here expecting total strangers to assist for nothing.

Water is sorted, we have an individual holding tank that will serve our property if pressure does drop during peak times.

Electricity... well Scottish Power Energy Networks have designed the system, think they know what they are doing...

And we are employing a SEPA drainage expert for the percolation test and drainage reports who will design a suitable system.

Don't think we need a project manager to do that mate, as it's all sorted and in the pipeline.

Why would I run cables for everyone... I'm not the original land developer, I have liaised with SP to identify a possible solution for connecting into the mains electric for everyone. Pretty sure everyone is happy I have done this for people. They aren't expecting me to lay and connect cable to there plots, I have no idea why you think I would do that.

Say you live on a normal street and everyones gates get stolen, are you going to go out and buy and fit everyone new gates... fair play if you are you must be a very generous and kind person...

We are not alienated with any plot owners, some are good friends some I have only met once as we haven't been on the site full time yet. The only person that we are alienated with is the original land developer, who in my opinion hasn't done fully what I expected from him. But life is to short to start a legal battle with him or fall out majorly... he will be one of our neighbours when he gets his lodge built so it's just not worth it!

"I find it somewhat offensive that you come here expecting total strangers to assist for nothing."

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Seems like your usually quite happy to give people free advice on a public forum, I don't understand why you are trying to lay in to me. Your clearly a very knowledgeable and helpful chap and Iv'e done nothing but respect everyones advice and knowledge.

 

[D Skelton]

Hug it out boys

 

[Engineer54]

I'm not laying any cable for anyone else... just our own plot.

There is a 10mm cable laid in at the moment, which isn't of any use to us - maybe a temporary supply for plugging in tools - that would be useful and save on petrol with the generator! Max load would be 25 amps as suggested by the engineer and calculations above.

Not crossing any plots, following the road. It has been measured countless times. 115m to the edge of the plot, then another 30m to the entry point in the dwelling.

I didn't think for a moment that you were, i was referring more, as to how these cables would be routed from the central position to the individual plots... Which you have now cleared up, by you stating that you are following the road.... Are you running this buried cable in ducting, or just direct buried??

Don't be tempted to run 2 core SWA rather than 3 core, using the Armour as the earth, it won't comply with main bonding requirements. To cut costs and reduce cable size, consider using 2 smaller cables in parallel. Direct cable burial over a 150m is going to need a lot of man hours to remove sharp stones and other debris from the cable trench floor and sifting of excavated soil for the first backfill layer after the soft sand. It could well turn out cheaper to duct the cable, which if planned correctly, could provide a means of replacing the cable(s) in the future, should it be deemed necessary....

Oh and if i were you, i'd get everything in writing from this Electrical Engineer you talk about. Is he the guy that produced the cable size print out you posted, because there are a few fundamental data errors on that calculation sheet??

 

[Richard Knight]

I didn't think for a moment that you were, i was referring more, as to how these cables would be routed from the central position to the individual plots... Which you have now cleared up, by you stating that you are following the road.... Are you running this buried cable in ducting, or just direct buried??

Don't be tempted to run 2 core SWA rather than 3 core, using the Armour as the earth, it won't comply with main bonding requirements. To cut costs and reduce cable size, consider using 2 smaller cables in parallel. Direct cable burial over a 150m is going to need a lot of man hours to remove sharp stones and other debris from the cable trench floor and sifting of excavated soil for the first backfill layer after the soft sand. It could well turn out cheaper to duct the cable, which if planned correctly, could provide a means of replacing the cable(s) in the future, should it be deemed necessary....

Oh and if i were you, i'd get everything in writing from this Electrical Engineer you talk about. Is he the guy that produced the cable size print out you posted, because there are a few fundamental data errors on that calculation sheet??

Currently the 10mm cable that the original land owner laid is just direct buried. When we did the excavations on site last month for the turning circle and retaining wall we laid down 30m of ducting from the edge of our plot to the dwelling entrance. For the sake of a few quid we will be laying ducting for the rest of the cable run.

Thanks for that tip regarding laying two cables, perhaps the current 10mm cable could be utilised somehow if it is fit for purpose.