Position of New Electricity Supply

[Willus]

We are buying a barn and as part of the conversion it is going to need to have a new electric supply. There are some adjoining barns that are also being converted by the owner and they are arranging the electric supply to those barns. To manage the costs they are going to get the supply to our barn done at the same time and we will just pay our share of the costs when the sale goes through. The question I have is about where to have the supply positioned, the barn is long and relatively thin about 40m by 6m. Due to the route of the cable we could have the electric come in almost anywhere along the front of the barn. Does it matter where it is positioned is somewhere in the middle better as far as running the rest of the electrics for the house or does it not really matter? As this is being done ahead of the sale we do not have all the plans drawn or an electrician to ask - so just trying to avoid an obvious mistake


Thanks

Will

[arco_iris]

Willus!

Fantastic opportunity to have the choice!

Wiring the rest of the building doesn't come into it - you want the incoming supply cable, meter, isolator and CONSUMER UNIT somewhere that you can hide them - perhaps in a cupboard?

These items should be close together, just remember that the SWITCHES of the consumer unit must be between 1350mm & 1450mm from the floor. So a full height cupboard, it can't go in a kitchen base unit, for example, but kitchen would be a good place for a smart unit? Or the utility room or boot room? Cloak cupboard in the entrance hall?

[Someone-Else]

You should find out what you are getting first.
It may only be the incoming supply, fuse and meter. Also you should ask what capacity the supply is, as soon you may want a car charger too, which will be no use if you only have a 40Amp supply. Also you can't really have a consumers unit fitted as you don't know how may circuits you will need.
Example: a 6 way consumers unit is fitted, and you decide on having an electric shower, electric cooker, sockets upstairs left, Sockets upstairs right, sockets down Left, sockets down right, where will the upstairs lights, the downstairs lights, the outside lights the burglar alarm get connected to? You may need a 12 way or bigger? you won't know until you design the interior

At this stage have a meter cupboard fitted and tell them to put the supply in there. (The consumers unit should be within 3M of the meter, but not tucked away in some pokey cupboard.)

[arco_iris]

Wasn't saying the CU would be fitted at this stage, OP is asking for suggestions as to where supply should enter the building.

I'm saying be aware and plan ahead. Would make sense for the items related to the incoming supply to all be in the same place.

Good shout on ensuring supply being sufficient for EV charging circuit though! Public charge points are expensive to use over charging at home.

[Neelix]

I suspect the supply company won’t be providing the trench or the external wall mounted cabinet for the DNO head.

This could get tricky, so best you make some decisions now and as it’s a barn maybe think about the outside appearance too as a white meter type cupboard could spoil the “looks”

[arco_iris]

as it’s a barn maybe think about the outside appearance too as a white meter type cupboard could spoil the “looks”

Neelix, it doesn't have to be white though, can you not get them in green & brown? May depend on what the neighbouring barns are getting.

With smart meters, is there a regulatory requirement for external access? I have an older property where the DNO head and meter are indoors.

[Neelix]

as it’s a barn maybe think about the outside appearance too as a white meter type cupboard could spoil the “looks”

Neelix, it doesn't have to be white though, can you not get them in green & brown? May depend on what the neighbouring barns are getting.

With smart meters, is there a regulatory requirement for external access? I have an older property where the DNO head and meter are indoors.

You’re correct it doesn’t have to be white but the new owners do need to carefully consider where they want it …..

As for smart meters, given how unreliable they are I suspect they would need to be accessible from the outside

[big-all]

general comments
it will be added cost per metre off dig or cable
if the future layout off windows or doors is unknown then near a corner may work best
keep in mind possible further expansion and avoid locating there
keep in mind out building and parking that may effect the location

[Someone-Else]

What will power the heating? I assume it will have to be electricity? If so, you will want an even bigger cable.

[Neelix]

Capacity for an EV charger needs to be considered too.

[Someone-Else]

Capacity for an EV charger needs to be considered too.

I already said that

as soon you may want a car charger too,

[Scotty001]

Willus, just to add more fuel to the fire (question to the mix) you mention that there are other barns being converted to residential properties that will also get a new supply. Has the "ORGANISER" of these new supplies been quoted by the electricity distribution company as yet? normally they will need to know the rating that each property will need (Inc if EV charging is req)
Reason for asking is the transformer (likely pole mounted if on an old farn) may be small (25/50kva) and that too may need an up rate as it was never designed to power 3+ residential dwellings and just barns. depending on the hv network capacity on that circuit it may be expensive or, VERY VERY VERY expensive. (OVER £45K) for a new transformer and associated cabling. As you will be paying for your share do you know how that will be worked out? Breaking it down per dwelling could be difficult, an Even split for everyone? (possibly getting stitched up like at a resteraunt, you may pay an equal amount but you had a salad and glass of water, the rest of the party had champaign lobster & caviar ) all things to consider.

[Willus]

All - thanks for the responses. The supply is actually being routed past the barn so we have a fair amount of flexibility in terms of where it comes in. If it does not make too much difference to the subsequent wiring of the barn I will probably have it come in at the corner of what will be the workshop area rather than in the main house that way we will have all of the space we need and no risk of it impacting where the windows will go. Heating is going to be ground source heat pump so dependent on electric but not direct electric heating.

In terms of the supply to the barn the local supply company is proposing "5 connections, each with an After Diversity Maximum Demand (ADMD) of 30 KvA" they are putting in a new new overhead HV spur with substation to support this. I was assuming that this was sufficient power?

Thanks

[Scotty001]

30kva for each property should be fine for most houses. Have YOU been told how much the hv spur, associated poles, transformer along with (I'm presuming) 95/185 waveform under ground main as well as 35mm concentric service is going to cost? It doesn't sound cheap.

[Neelix]

All - thanks for the responses. The supply is actually being routed past the barn so we have a fair amount of flexibility in terms of where it comes in. If it does not make too much difference to the subsequent wiring of the barn I will probably have it come in at the corner of what will be the workshop area rather than in the main house that way we will have all of the space we need and no risk of it impacting where the windows will go. Heating is going to be ground source heat pump so dependent on electric but not direct electric heating.

In terms of the supply to the barn the local supply company is proposing "5 connections, each with an After Diversity Maximum Demand (ADMD) of 30 KvA" they are putting in a new new overhead HV spur with substation to support this. I was assuming that this was sufficient power?

Thanks

You really need to get a couple of local sparks to work with you.

Ground source heat pumps sound good in principle but I'm not convinced as yet - your construction, insulation and complete heating and ventilating system will need to be sound to ensure you don't need to add extra heating