"It's been something of a wild voyage of discovery so far this renovation has, but we're just speccing the electrics so we can include a change-over switch and external gennie/power station connections from the word go."
I'd be interested in hearing more about this - I'm in a similar position to yourself and would like the functional redundancy to have some backup options available.
It wasn't too difficult. EVERYTHING in the property needs replacing- every electrical component from the mains incoming (including the consumer unit) onwards. It's a full rewire. So having worked through what we want and where, we then walked around with the electrician and discussed with him what we wanted. That includes external sockets, supply to workshop, changeover switch etc etc etc.
One of the advantages of having such a major renovation is not worrying about what is existing. Took the place back to a bare shell (and I mean a bare shell- first floor and all internal walls out so the first floor joists could be replaced).
We explained to the electrician that in event of a power cut, we want to be able to plug in a gennie or power station to keep essentials like a fridge/freezer going, obviously "essentials" will now include a PSP. So a change-over switch- a manual one is fine- is needed.
This property is the gift that keeps giving. So far, in addition to the extensions, the work includes rebuilding and lining the chimneys, removal of all old render, replacement of rotting window lintels, new eternal windows/doors to match those in the extension, all plaster off inside, new lime-based render on outside, insulated boarding on inside, full replacement of first floor including joists, removal of old first floor ceiling, reinforce roof trusses and replace ceiling, re-insulate, dig up ground floor and put in new floor with insulation and level it, obviously full re-wire and replacement of all plumbing and new internal walls, replacement of old steep narrow staircase with modern 2-leg version. Most of it we anticipated, but the new upstairs joists and re-doing the outside render on the old part has been extra. Ditto the old septic tank replacement.
There's a reason that many of these old farmhouses are virtually un-sellable to a private buyer unless you find a cash buyer. Just cannot get mortgages on them, and they need a lot of work. But- if you get a decent location it's very worthwhile. It's not a cheap option, you will end up paying the same as for a habitable equivalent, but at least you know exactly what went into it and what state of repair it's in.
GC