But you have to fill up a lot there? Or is there a basement.
The complete "drama" is here:
https://www.hausbau-forum.de/threads/Reihenendhaus-mit-gue-in-Eigenregie-bauen.31198/
Otherwise, we will make strip foundations and the rest will then be filled up. However, no good material needs to be placed between the foundations, as the base slab will not be load-bearing. That way we can throw the excavated clay in there.
The rest must then be backfilled accordingly with proper material.