Initial floor plan on graph paper: slope, basement + 2 floors.

Disclaimer:
After a long search, we have now found a plot of land. It is not really easy to build on because it has a steep slope, but it also has a special charm since the north and south sides are undeveloped and will remain so at least in the medium term (both plots belong to the neighbors above). In addition, we have a view of the river and the vineyards behind it to the north, east and southeast. Therefore, we want to build two floors on the basement in order to get as high as possible with these and be able to access the garden on the ground floor from the 1st upper floor.

The shown design comes from our “dream vision.” We have noted our room concept and our wishes and drawn them on graph paper. 1 square corresponds to 1m.
We set a budget of 500,000 euros excluding the plot and garden.

Development plan/restrictions
Plot size: 682 sqm
Slope: Yes, slope approx. 6m from west to east
Gap in old development area, no development plan available, similar houses already built

Requirements of the builders
Style, roof shape, building type: open, modern, clearly structured, roof shape depending on meaningfulness (height, appearance, photovoltaics)
Basement, floors: basement/entrance area + 2 floors
Number of people: 2 adults, 31 and 31, no children yet, 2 children’s rooms planned
Room requirements:
Basement: entrance area, office, garage, storage room, technical room
1st floor: living, dining, kitchen, utility room, WC, pantry
2nd floor: 2 children’s rooms, children’s bathroom, parents’ bathroom, bedroom, walk-in closet
Guests per year: 4 (sofa bed in office or utility room)
Open or closed architecture: open
Conservative or modern construction: modern
Open kitchen, cooking island: open, large + cooking island
Number of dining seats: large dining table (2.40m x 1m), 6 – 8 people
Fireplace: can have, but does not have to (not planned, due to cost/benefit)
Music/stereo wall: record player in living/dining area
Balcony, roof terrace: balcony on the east side on the 2nd floor would be great, because of location and view
Garage, carport: double garage in basement, 2 parking spaces in front
Other wishes/special features/daily routine:
The north and south sides of the plot are undeveloped in the short and medium term. There is a quiet street to the east (cul-de-sac, 3 houses after us). From north over east to south there is a view of the river, so we would like to have the option to go out at least on a narrow balcony on the 1st and 2nd floors. Garden planned on the south side of the plot.
The cooking/dining/living area should be as spacious and bright as possible. The other rooms should be practical.

House design
Source of the planning: builders
-Do-it-Yourself
What do you particularly like? Why?
Clear layout, large area for “living,” children’s bathroom housed
What do you not like? Why?
- Staircase wish is platform stairs, which would be too large for the current plan
- Price calculation?

Personal price limit for the house, incl. equipment: 500,000 euros excluding outdoor facilities, preferably through a general contractor
Preferred heating technology: air-water heat pump

If you have to do without, which details/expansions
-you can do without:
fireplace, possibly balcony on the 2nd floor (reluctantly), smaller living/dining area
-you cannot do without:
children’s bathroom, open and spacious design, office, utility room

Why did the design turn out as it is now?
Design according to room concept and orientation on the plot. The house should extend as far as possible to the northeast to realize the garden in the south and west.
Note: The red hatched area of the basement is planned so that the house does not look like a residential tower. The basement is planned to be wider for optical reasons. In addition, the basement ceiling should protrude about 2m and thus form a porch and be used as a terrace of the 1st floor.

What is the most important/basic question about the floor plan summarized in 130 characters?
1. Is the floor plan usable as a planning basis for providers/architects?
2. What works well/less well/not at all?

The house should be placed as far northeast as possible in order to realize the garden in the south and west.

It would be sensible to draw in the building envelope. Then cut the house once and move it around on the property.

1. Is the floor plan usable as a planning basis for suppliers/architects?

Yes, absolutely excellent. Thanks for the analog drawing "instead of" the usual "my 3D freeware studied architecture" clicky-colorful.

2. What works well/less well/not at all?

I would rather say, "what still needs to be clarified" – namely, how to deal with the fact that contrary to the principle sketch, in reality you obviously cannot build gross for net with zero wall thickness. If you want to make me happy as well on the side, proceed similarly regarding the elevations; and use the grid of the squares to mark height points. I would also find it useful to mark in the floor plans the locations where certain wishes should be implemented (which you then illustrate to the architect, e.g., with photos of examples).

Thank you for your response! I wanted to wait a few days to see if anyone else wanted to comment before I replied myself.

It would make sense to draw in the building envelope. And then cut out the house once and move it around the property.

I have requested the exact site and development plan from the municipality. However, the building authority is closed until January 11th. Either way, we are hopeful to be able to place the house in the northeastern corner while observing the setback rules. Since it is an old residential area, I am assuming §34 applies. Several other houses have been built similarly there.

I would rather say, "what still needs to be clarified" — namely, how to deal with the fact that, contrary to the conceptual sketch, you obviously cannot really build gross for net with zero wall thickness.

The wall thickness issue also causes us doubts. However, I also very much expected that our amateur initial draft here would be heavily criticized and that we would be advised to start the planning anew.

Another important question we are asking ourselves:
Is this house size (basement + two floors) on a slope realistically achievable for 500,000 - 550,000 euros turnkey including earth and retaining work but without garden and kitchen?

Six meters of slope over 21.5 meters, that would be twenty-eight percent, and certainly also more than a whole floor of height difference in the building envelope. I don’t see at least much knee wall or even a "city villa" there. And for aerial photos, there is Google Earth, you don’t need an open building authority for that.

The wall thickness problem also gives us doubts. However, I have also much more assumed that our amateurish initial design will be quite torn apart here and we will be advised to plan from scratch.

I also do not set wall thicknesses in the preliminary design and here meant rather generally the awareness of gross and net in the dimensions.

Where have you planned the garden access from? Can you please mark it? With the budget, you should plan the basement differently and include it more.

The drawing already shows a preferred living feeling - I like that. The rooms above facing the street will become tight if the house does not become wider overall. If partitions in the living area reach the ceiling, the living area will become very cramped. Downstairs, a lot of space is created for things standing around. Great for bikes, strollers, and all kinds of bulky everyday stuff that can be stored at the entrance. These large areas are expensive when you calculate them as a share of the construction costs. But I also find the idea of a "Dreckschleuse" in the basement great. A second "official" house entrance on the middle level right next to the toilet would save the "tidying up for guests." It would be very practical. Whether the budget is sufficient also depends on the floor condition and the equipment requirements. To me, it seems tight.