Open design - semi-detached house without neighbors?

Good morning everyone,

I am considering buying a plot of land in a new development area. According to the development plan, this involves an open construction method, where both single-family and semi-detached houses are permitted.

I am now wondering how exactly the semi-detached houses are supposed to work. Do two have to "randomly" find each other?
What happens if one person wants to build a semi-detached house, but their immediate neighbors do not?

I probably have a big misconception. Could you help me with that?

Thank you very much in advance!

Closed construction method: Building the house on the side property boundary. This means the exterior walls of the adjacent houses touch each other. Open construction method: Distance to the property boundary (presumably at least 3m)

both single-family and semi-detached houses are permitted. What if someone wants to build one half of a semi-detached house, but their immediate neighbors do not?

What your neighbors build does not matter to you. What is important is what YOU want and are allowed to build on YOUR property. The plot is probably large enough to accommodate a semi-detached house. What matters is how much area you are allowed to build on (site coverage ratio, floor area ratio). If you are allowed to build 180 sqm of site coverage, that is definitely sufficient for a semi-detached house. Since both semi-detached and single-family houses are permitted, you can also build a single-family house with 180 sqm site coverage. Or a house with 100 sqm site coverage and enjoy a larger garden. The maximum buildable site coverage is not the same as the maximum living space, see floor area ratio, (floor area ratio, plot size x floor area ratio = total floor area). The number of possible floors and other information can also be found in the development plan.

I am now wondering exactly how the semi-detached houses are supposed to work. Do two have to "randomly" find each other?
What if one wants to build a semi-detached house but their immediate neighbors do not?

I am probably making a big mistake in thinking. Could you help me out?

The mistake is that the semi-detached house is built on "your" property. So not one half on your property and one half on the neighbor's property, but both halves stand on one property.

If the property is 600m², you can either put a single-family house on it just for yourself, or you basically divide the property and put one semi-detached half on 300m² and the other on the other 300m². And then it is your job to find a partner for the other half.

I have also often seen that in a development area almost only semi-detached house plots were offered. Then interested parties can either buy one of them (for a semi-detached house) or the double pack (for a single-family house). Of course, if only one large plot is available, in case of need one would have to divide it according to [WEG] and find a partner oneself - or simply divide it in reality and sell the unwanted half again for development with a semi-detached house.

I am now wondering how exactly it is supposed to work with semi-detached houses.

If you are lucky, the municipality or the seller has already thought about the issue and it is/is going to be regulated, e.g. in the purchase contract or by development obligations.

Do two have to "accidentally" find each other?

If you are unlucky, yes.

What if one wants to build a semi-detached house, but their immediate neighbors do not?

Without further regulation, the rule is: first come, first served. That means whoever submits the building application first determines whether to build on the boundary or with a setback from the boundary.

Presumably I have a big misconception.

I’m afraid not.

presumably at least 3m

No. Building code 2.5m.

You don’t have to care what the neighbors build.

No.

What matters is what YOU want and are allowed to build on YOUR property.

No. If the neighbor has already planned and submitted with a setback from the boundary, the builder must also build with a setback.

The misconception is that the semi-detached house is built on "your" property.

No. Semi-detached house in terms of planning law means two houses built next to each other with a separating property boundary.

Are we talking past each other here?

TE buys plot A, 700 sqm, the development plan says "single-family house or semi-detached house is allowed."
His neighbor buys plot B, also 700 sqm. He brings someone else and they build a semi-detached house (connected by a thick wall). However, the neighbor on plot B must – due to open construction – maintain a minimum distance to plot A. And TE is free on plot A to choose: single-family house or semi-detached house – regardless of what is built on plot B.