Semi-detached house once with and without a basement! Who pays?

I would hardly claim now that you have to pay.

Why should he have to pay for the neighbor's wish for a basement??? And if you own the property, it is not a developer. In that case, the situation might be different again, any additional costs were, in my opinion, even less your problem. Many greetings! mini

I find the 10TEUR quite tight. We had a similar initial situation and after several discussions, we decided against a basement. Nevertheless, you will not have to pay a single cent for it. Where would we be if we had to share costs for a neighbor's basement?

First of all, he should not partially bear the costs for the basement of the other, but his foundation loads from the base slab, strip foundations, etc. must not burden the neighbor's basement. The loads from his house must therefore be carried deeper, i.e. down to the foundation level of the neighbor.

First of all, he should not proportionally take over the costs for the neighbor's basement, but his foundation loads from the base slab, strip foundations, etc. must not burden the neighbor's basement. Therefore, the loads from his house must be carried deeper, i.e. down to the neighbor’s foundation level.

I don't see it that way. If anything, the neighbor should bear this better execution. The base slab does not load the basement.
I remember that had similar issues with his house. It was described in detail there. Maybe he can explain it.

But again, what kind of contract is it now? If it's a developer and signed, he couldn't care less. He ordered the house without a basement at price X.

Best regards! mini

But the foundation slab significantly burdens the basement due to horizontal earth pressure. And the loads do not come from the foundation slab alone, but from loads from the entire house and the associated traffic loads.

For me, something like this belongs in the development plan. The one who builds first must either build with a basement or establish the foundation at basement level. Then every discussion is nipped in the bud and every buyer knows what they are getting into.