To me, it looks like two plots and two semi-detached houses.
Good point - either that (where the semi-detached houses would then share a common pitched roof with a ridge in the middle :confused:), or the intended ridge line is drawn beyond the building window. However, the two garage building windows speak against that...
As I see it, there is about a 2 - 3 meter height difference diagonally across the building window.
So the house should be almost completely out of the ground at least at the lower end of the building window (south), right?
Level access would thus only be possible from the upper end of the plan (north?).
Regards,
Dirk