Multi-generational house with underground garage for 3 families

If I understand correctly, it is supposed to be a three-family house in the sense of two family apartments and one granny flat. And it should have an underground garage. For this, 1000 sqm is borderline: the more level the ground, the better a house of this size can be built on it; however, an underground garage also needs an access ramp. The longer this has to be (because the plot doesn't help to overcome the height difference), the more space it consumes (and takes away from the parking spaces for which it is intended). An underground garage with six parking spaces is a spatial Pyrrhic victory. Double parkers would be more economical. By the way: playing landlord with two parties each around half a housing unit size is not really worthwhile either.

And, Hang? Site plan really oriented to north? (Unfortunately, one always has to ask here because that is often not the case and the north arrow is missing).

What is also No. 8 .. houses, sheds?

2x200sqm and granny flat .. how big? If for parents, what criteria?

Longer building structure, each main unit 10 meters in length, with an additional 10 meters in between for barrier-free access for the parents' granny flat, total width max 11 meters (then there is still 3 meters terrace depth to the south for the boundary distances in the north and south), leaving 20 meters garden or driveway, divided into west and east. On the west side, driveway to an underground garage shifts the equivalent garden use for the two main apartments slightly to the east. Remaining in the east approx. 8 meters x 20 meters (160 sqm garden), in the west due to driveway/access underground garage and entrances 12 x 12, so 144 sqm garden. In addition, of course, the sqm of the accesses (each 10 x 3) as well as the terrace sides (each 6 x 10), where each has a 3-meter deep terrace. Upper floor (the sqm above the granny flat may also be shared by the main apartments). If you then subtract a strip of hedge of about one meter everywhere, not much remains. May be enough for some, not for others.

If I understand correctly, it is supposed to be a three-family house in the sense of two family apartments and one granny flat. And there should be an underground garage. For that, 1000 sqm is borderline: the flatter, the better a house of this size can be built on it;

Hello 11ant. First of all, many thanks for your explanations. Yes, your definition hits the nail on the head. We are fully aware that 1000 sqm is borderline. Especially if you want to keep some garden. Nevertheless, I think the condition is given. The plot is completely flat and we have no slope at all.

An underground garage with six parking spaces is a hollow victory in terms of space.

If it works out that way, I would also call it a hollow victory!

By the way: playing landlord with two parties the size of half a residential unit each is not really worth it.

Currently, there is no plan to rent out the granny flat. Later on, the granny flat will not be used for rental purposes either. The idea of tandem parking is definitely worth considering. Personally, I find it a pity that quite some space is lost or could be lost here. Do you perhaps have a visual suggestion for this?

And, slope? Is the site plan really oriented north? (unfortunately you always have to ask here, because often it is not the case and the north arrow is missing).

Hello kbt09. Many thanks to you as well for your questions. The site plan is oriented north. There is no slope. The plot is completely flat. No. 8 consists of a single-family house (2 full floors / converted attic / hipped roof). At the boundary of the plot, there is also a large former garage that serves as a workspace.

2x 200 sqm and granny flat... how big? If for parents, what criteria?

Two times 200 sqm would probably be the maximum and, in our view, quite conceivable. For the granny flat, 60 sqm - 70 sqm would be absolutely feasible. Barrier-free is of course important, although this could also be solved by means of an elevator. Otherwise, there are no major demands on the granny flat, since it will only serve the parents as a "base," as they are away for about 6 - 7 months of the year (as long as health permits).

Thank you very much and best regards.

Longer building structure, 10 meters length per main unit, in between another 10 meters length for the granny flat for the parents due to accessibility, total width max 11 meters (then there is still 3 meters terrace depth to the boundary distances in the north and south), remaining 20 meters garden or driveway, divided into west and east. On the west side, driveway to an underground garage shifts the equivalent garden use for the two main apartments slightly to the east. Remaining in the east about 8 meters x 20 meters (160 sqm garden), in the west due to the driveway/access to the underground garage and entrances 12 x 12, so 144 sqm garden. Additionally, of course, the sqm of the accesses (each 10 x 3) as well as the terrace sides (each 6 x 10), where each has a 3 meter deep terrace.
Upper floor (also the sqm above the granny flat may be shared by the main apartments).
If you then subtract a hedge strip of about one meter everywhere, not much remains.
May be enough for one, not for another.

Hello ypg. Thank you very much for your explanations. I will try to visualize it (which is always a bit difficult for me)!

Hello ypg. Thank you very much for your explanations. I’m trying to visualize it (which is always a bit difficult for me)!

You just have to imagine a building body about 30 meters long and 11 meters wide. Visually, it resembles a triplex row house.
In front the driveway plus entrance ... but also 144 sqm garden of the western third, and in the back 160 sqm of the rear garden in the east.
That is the simple version and it already stretches the plot to the limit.

My honest opinion: if you already have so much money that it allegedly doesn’t matter here, then I wouldn’t put myself through a) building in a cramped and controlled space with family members (it’s not airy anymore here) and b) basically not violating a plot like that.