House on a slope with 2 granny flats

Then the private path must remain What if the garage cannot be used as a terrace as planned? Think carefully about how you want to design the garden. And have the earthworks done at the same time. Be careful, with the slope you can end up spending six figures without having anything special.

Are you allowed to build that big? I'm not quite sure about the floor area ratio.

Floor area ratio: I come up with 387 m², that should be just enough (I think)

Floor area ratio
Floor area, not living area!

does the floor area ratio only refer to full floors?

But you haven't done anything about the conceptual errors of the floor plan. Hallway in the children/parent area is 275 cm wide ... for hallway and platform stairs ... that's already overwhelming, so it's obsolete.

With a knee wall of 200 cm, windows that are also supposed to have roller shutters end at a maximum height of 160 cm, meaning glass up to about 150 cm height. So you enter rooms and the view mostly faces the wall.

Looks like a "layman with heavy equipment" to me. I see a mega-box here driven by the misconception that you have to build on the plot to the maximum. However, why this is the case is unclear. Do you want to avoid meadow or bushes at all costs? Does the million have to be burned for sure? Do you need a representative hut to boost self-esteem? Or are you going to build two granny flats for a nanny and butler right away? What exactly?

The slope only adds to the confusion of the OP, since as a layman he obviously lacks ideas for an adequate use.

Before you put the cart before the horse, I would recommend you first create a needs list - independent of the slope. Which rooms must be there, how big should they be, which special features are mandatory (e.g. kitchen island, fireplace, etc.), number of parking spaces, special wishes, etc. - simply everything.

With that, the floor plan and the budget, you go to the architect (whom you have to pay anyway) and have a plan created. Own attempts are nice, but for a million I would set aside the money for the architect - after all, he studied several years for it.

Apart from that: if the granny flat is not to be used to bring grandma into the house or the above-mentioned employees, forget the nonsense. The costs are far higher than what you can earn with it in 20 years.

@Escroda does the floor area ratio only apply to full floors?

Unless there are deviating or supplementary regulations specified in the development plan, - yes, for development plans that have been publicly accessible since 1990 - no, for development plans that have been publicly accessible before 1990. For public access in 1990, one must take a closer look.

okay, we have returned from our exam. [...] We have also taken the other suggestions seriously and implemented most of them.

Well, without mockery but with irony: Congratulations! (on the masterful feat of achieving no significant improvement despite many changes).

For that, we raised the kneewall in the upper floor (which is now somehow the attic) from 150 cm to 200 cm, so that we have windows to the side and not everywhere sloping roofs in the upper floor.

The "top edge" of the kneewall is always also an equator – or better said, a Rubicon – separating facade windows from roof windows. In other words – or as Kerstin explained above – you virtually lay a beam at this height in your view (exception: windows extending beyond this kink in both components, of which, as a former window manufacturer, I have a good idea why they were only briefly fashionable almost 40 years ago; or you break through this line with dormers). In the dream houses of soccer referees, such mega kneewalls do not occur – they know what "offside" means.

Before you put the cart before the horse, I would recommend you first make a list of requirements – regardless of the slope.

And afterwards, it makes sense to take a look at – in his thread , you can not only commiserate about current budget overruns, but also see an example of how to accumulate dark rooms on the uphill side in a steep slope situation. Here too there is (only one) granny flat upstairs, although the access is also from the uphill side – so you have to rethink accordingly.