Planning a Single-Family House on a Slope - Optimally Utilizing the Plot

As long as we are in sketch mode, everything is still possible. The wardrobe can be inserted on the left or on the right side of the plan. The guest room can be moved further down the plan, the other rooms can rotate... the garage, which does not allow a window, is no problem either.

answer with "yes" or "no" - so not influenced by the degree of increasing frailty. The thought "Grandma lives with us" should be sympathetic even without a walker or should be left alone.

Of course, frailty is a big factor! I actually see the problem that a lady with a past should be taken in selflessly, but is separated from the center of life. To me, that is implemented inconsistently. One wants to, but cannot. Or one can, but does not want to. I see the old lady, whether frail or not, at least in a condition that she moves to the children, then rather centrally, that means in the hobby room with an exit on the side... the space is available.

that means in the hobby room with an exit on the side

No, not in any only in case of emergency repurposed room, but: in a room planned for and with Grandma.

No, not in any only in emergencies repurposed room, but: in a room planned for and with grandma.

We would agree with you here if grandma's move-in was already fixed or foreseeable. The grandparents are currently in their early 60s, in good shape, and live on a farm over 3 hours away. Assuming the current condition of the great-grandmother, who is also still very fit at the proud age of 93 and active on the farm, we hopefully are still talking about many, many years before the possibility of a move-in might occur. Therefore, we think that the discussion here has drifted a bit in the wrong direction for us. Please don't misunderstand, but we are not building the house for a grandma who might possibly move in many years from now, but as a place where we want to raise our children and live as a small family. It is reassuring to have the option and the space to possibly accommodate someone, but it should not be the main focus of our planning.

Good - if "Oma ante Portas" is still so far away that the children may already have moved out by then, it is of course pointless to deal with it now. I just wanted to say: if you yourself say "yes" to the idea "Grandma lives with us," then it should be an unequivocal yes, supported by everyone - including the house. And the latter I only see with intended rooms, but not with repurposed (and only moderately suitable for the new purpose) rooms. "Grandma lives with us" means "grandma-focused room, in the right place," or it only works moderately.

Here is a new version of the plan (created without a planner due to vacation, so please don’t be too harsh) incorporating some of your tips:

The stairs have been moved to the left side and swapped in arrangement.
The wardrobe on the upper floor and the utility room have moved to the right. The utility room has also been made larger and hopefully more usable as a result.
Due to the lack of space for an additional door, the toilet has been integrated into the bathroom. What do you think of the arrangement of the shower, bathtub, and toilet in the room? Would that be livable? Honestly, we’re not quite happy with it yet. Maybe someone has a better idea for the arrangement of the elements or the two rooms relative to each other?
(The currently unused room between the bathroom and garage can, if the floor plan remains as is, be allocated to the garage.)

The shifting of the stairs also benefits the storage room behind the kitchen on the lower ground floor, which has become somewhat larger. The part of the hallway in front of the bedrooms is quite wide at nearly 1.7m. If storage space really becomes an issue, a wardrobe could be placed in front of the middle room.

We would have to accept losses in the walk-in closet due to the changes. We can only fit about 6m of closet space in there sensibly now.

The garage has been made slightly shorter. With the version from the initial post, we had already slightly exceeded the maximum buildable area.

We look forward to your feedback – please be as critical as usual!

Hmm, grandma is a possible maybe option. With the existing floor plan, grandma/grandpa must be able to manage without help and without a walker. This is a classic case of "if you say A, you must also say B." If grandma/grandpa might come in an emergency, then the house must accommodate that. It’s not enough to just have their own room. Bigger bathroom, no thresholds, no steps, etc.—that can’t be done later. A grandma with a walker or a grandpa who needs a caregiver in the morning can’t use the bathroom as planned, not even the one on the ground floor. Either do it properly (create the conditions in the floor plan, turning circles, etc., no wheelchair-inaccessible sinks and things like that—those can’t be done later) or not at all. If I take the approach of a house for a 4-person family without grandma: Do you, as a 4-person family, need 2 bathrooms on one floor or would you prefer 1 with a separate toilet? If no, use the grandma bathroom as a utility room and plan a bathroom with a separate toilet. Regarding the toilet as a possible compromise between open/separate (unfortunately I can’t find a picture now): the toilet gets a niche with a glass door leading to the main bathroom. Do you understand what I mean?