Cooling ceilings instead of air conditioning, is it sensible?

The old house has 152 m² of living space, which was enough for that. That won't be enough for the new house with 215 m², right?

Why does the new house have 215 sqm when 152 sqm was enough so far? - exchanging a noisy neighbor for more closeness to relatives doesn't increase the space requirement by 40% ... I hope those aren't your favorite numbers and the next house will then have 521 ;-)

Why, it fits after all: You build the first house for your enemy, the second for your friend, and the third for yourself.

;-)

Why does the new house have 215 sqm when 152 sqm were enough before? - swapping a noisy neighbor for being closer to relatives doesn't increase the space requirement by 40% ... I hope those aren't your favorite numbers and the next house will have 521 ;-)

If I build another house, then definitely with 521 sqm. Somehow I have to remember my EC pin. :P
(Joke. joke. before someone calls me internet-naive again).

No, the first house was planned with little equity and financing stretched to the limit. That was relatively compromising. The new one, on the other hand, was the "wish-for" house, where we initially planned to reduce if it didn’t fit financially, but now we intend to go through with it if it fits financially, because it requires almost no compromises.

Your split units are separate and not (sensibly) combinable with the ventilation ducts of the controlled residential ventilation. Controlled residential ventilation with cooling is something completely different. We have that. However, exchange rates of at least 5 times per hour are required. It is not suitable for a normal single-family house. More efficient is controlled residential ventilation and the split units.