Noise problems soundproofing new build semi-detached house?

Are you as audible to the neighbors? Apparently something is coupled, maybe no floating screed or floor coverings have contact with the wall...

According to the neighbors, they don’t hear anything from us. But we are also considerate. For example, we noticed quite early on that when walking on socks, the impact noise is stronger than when I wear slippers, so since then we have been wearing slippers. In addition, the neighbors like gaming very much and wear headphones; their own statement is that they then don’t hear anything. And when the neighbors walk through the house in the evening (to the bathroom, downstairs, etc., which I notice), we are already in bed.

I suspect that you are the "problem." The neighbors don't seem to have any issues with "noise," only you do. So don't start looking for any reasons, just move out.

Find it unusual that you can hear the neighbors so clearly in a new building. Even as a noise-sensitive person, there shouldn’t really be anything to hear, right?

I suspect that you are the "problem". The neighbors don't seem to have any problems with "noise", only you. So don't look for any issues first, just move out.

Based on experience with a semi-detached house, I would say that we are not the problem. The noises in the house have also been noticed by other people who visited.

I find it unusual that you can hear the neighbors so clearly in a new building. Even as a noise-sensitive person, there shouldn't actually be anything to hear, right?

That is also our opinion, especially since we know what it is like to live in a semi-detached house. But hearing the creaking of the bed or the placing of glasses on the bedside tables next door is not normal.

And when the neighbors walk through the house in the evening (to the bathroom, downstairs, etc. I perceive that) we are already in bed.

Wait a minute. It is normal to hear dull noises, for example walking on a wooden staircase (vibrations) that is attached to the partition wall. I don't know anyone who wastes a topic on that. If THAT is what you mean by noise problem, then it is not one. Perceiving and noise are different things. Maybe you confuse that because you are very sensitive. I find the thing with slippers quite questionable. With a concrete ceiling, it can also happen that the walking style causes dull noises. However, it is just like that, just as you hear car doors slamming through an outer wall as well as bird chirping, but it is unpleasantly perceived by very few. However, I know people who cannot filter out "background noises." That is, of course, a personal problem.