Evaluation floor plan approx. 145 sqm single-family house basement/ground floor/upper floor

Sloppy certainly not, I can assure you,

I gladly believe that you were fully committed. But the fact that a room which is ultimately dispensable (and which alone justifies including the basement in the thermal envelope) is still in the program when the design is made speaks against the thorough completion of phases 1 and 2 as "process components".

That one side remains free is very certain. The municipality will not develop any more building plots.

enviable... an priceless property. Please accept the gift.

I am willing to believe that you were fully committed. But the fact that a ultimately dispensable (and solely justifying the inclusion of the basement in the thermal envelope) room is still in the plan when the design is made argues against the performance phases 1 and 2 being thoroughly worked through as "process components."

Yes, I have to say, if it would have such an impact on the construction costs, I rather see our architect (with all due praise) obligated to point that out to us. So would my thought of moving the office out of the basement be basically sensible? Could you briefly describe what would then change in the construction? I think I have basically understood it, but I don’t want to come across with half-knowledge and get into trouble again ;-)

Yes, but then I have to say, if it had such an impact on the construction costs, I would rather see our architect (with all due praise) responsible for pointing this out to us.

That's how it is. I can already see that in the seventh part of my five-part series "A House Building Schedule, Also for You: the Phase Model of the HOAI" I will have to address what expectations builders should place on their architect. Many thanks for your hint about this imperfection!

So, would my idea of moving the office out of the basement be basically sensible?
Can you briefly describe what would then change in the construction? I think I basically understood it, but I don't want to come across here with half-knowledge and get into trouble again ;-)

Here we only intend to build walls – not to get on anyone’s nerves. Lack of knowledge is the privilege of the layman; no one needs to be ashamed of that. At most for resistance to advice (from other people in other threads: the fundamental rejection of architects; here perhaps: the rejection of a coat niche). I suspect you have an experienced architect – however, not experienced in "bringing along" the clients during the planning process, and probably also from pre-Energy Saving Ordinance times. Briefly described, removing the office from the basement meant the possibility of removing the basement from the thermal envelope, and thus that only one boundary surface of the basement – namely the ceiling between basement and ground floor – instead of five here – namely the foundation slab instead of the floor slab and additionally the four enclosing walls – would have to be insulated.

Briefly described, the removal of the office from the basement meant the possibility of removing the basement from the thermal envelope and thus that only one boundary surface of the basement - namely the ceiling between basement and ground floor - instead of five right here - namely the foundation slab instead of the floor slab and additionally the four enclosing walls - would need to be insulated.

Theoretically correct, but practically there is still the staircase, which creates a connection to the thermal envelope. It can be technically solved, but it is effortful and inelegant again. Besides, I have a whole floor of unused usable space. It can be done, but it is expensive, makes the house excessively bulky, and I therefore find it not sensible on a slope with valley-side access.

In this case, it really seems better to throw the parking spaces out of the house and share the basement/cellar. The only disadvantage: it has to be newly planned.

Theoretically correct, practically [...] I have an entire floor of unexploited usable space.

Thanks for the hint that what I didn’t say was wrongly interpreted. I only wanted to explain to the OP what he had asked. Unfortunately, this can easily be misunderstood as confirmation to basically stick with this building concept and only "reconceptualize" the thermal insulation. But of course, a complete change is the better way here: residential use of the basement, in my opinion best also with an entrance at street level instead of "above", overall two-story U+I. And as always, I have no objections to simply using what remains for the parking space instead of providing anything equal, the metal child belongs at the kids' table.

Only disadvantage: must be newly planned.

Big advantage for the client: it must be newly planned. I only see a disadvantage in the architect’s need to explain.