I cannot help feeling the 4 small pole pigs and what looks like the parallel PME earthing is asking for trouble

Might be PNB - which should be less troublesome (unless they really have combined everything together later on - and the busbar chamber isn't just for 4 separate metering CTs)

  -  Andy.

What if the loads I mentioned were specified and you 'had' to install them. Would you keep a single phase 100A supply or suggest an upgrade to 3 phase?

I'd probably want more information (sorry!) - what's the building heat loss likely to be? (i.e. how much will the heating draw long term) - what's the cost of an upgrade to 3-phase? (unless you already have a 3-phase head and it's just a matter of upgrading the metering, it can get eye-watering expensive quite quickly, as DNO's tend to ask for the actual costs if doing things these days - unlike the old electricity board days, they can't subsidise connections on the basis of future income from your bill). How much room for expansion would you like? (e.g. EV charge point). How acceptable would load-shedding be? (common practice in France, where you'd be expected to manage on a 45A single phase supply). I think I'd look at a supply upgrade as a last resort.

   - Andy.

Hi,

Is the space heating night storage heating?

You would have to use your professional judgment as to what loads would be simultaneously connected for a duration of over a few minutes.

A lot of electric only dwellings have such a schedule and never have any issues as long as the DNO has made their connections well and the cut-out clamps are tightened properly.

It strikes me that cheaping out on the heating may prove expensive when paying the electricity bills.  Any reason you're not going for modern high heat retention storage heaters, or a heat pump?

AJJewsbury said:

it can get eye-watering expensive quite quickly

I paid about £1500 for a completely new supply including digging up the road. I don't think that 3-phase was much more expensive than single. Of course if the service cable needs to be replaced, that is going to make an upgrade rather costly.

I don't like storage heaters (plus I think they are phasing out cheaper night tariffs) and don't want a wet system, just ripped one out!

Ok thanks for the advice.

https://www.youtube.com/watch?v=GhAKMAcmJFg

I also like simplicity and minimalism!

well, nothing is cheaper to run than thermal insulation, once it has been installed.

A very general problem in the UK is that we have had 40 years of cheap north sea gas, and our newer buildings reflect the assumption that it will carry on being available for ever, Which it won't. And then our older buildings pre-date insulation altogether.

Mike.