Actually, I would prefer not to take the slope of the site into account inside the house at all and instead accept high costs in the outdoor area. At least that’s my layman’s idea. I thought we have an ascending driveway, a level house, and at the back we hold back the terrain with a wall...
I can understand that, and if possible, it would usually be my preferred solution too, as long as the slope isn’t too steep. I’m also not a fan of split-level or have ever seen it in real life, so I find it hard to imagine. How steep is your slope? It looks quite “severe” slope-wise for you. Our building area also has a slight slope; our plot, with a width of 21 m, has a height difference of about 1.20 m (so our slope runs from left to right along the street front, not like yours from front to back). So on one side, we excavated a bit, and on the other side, we filled up a bit and didn’t consider the “slope” inside the house at all. So far, everyone in our building area—including those who have the slope like you do, running from front to back along the length of the plot—has applied the solution you quoted above: a slightly ascending driveway, a level house (above street level), and then adapting the garden terrain to the original terrain in the back with a wall or something similar. What does your architect say about the solution you want? Of course, if the slope is significantly steeper than, for example, ours, I imagine it could be more difficult. Have neighbors already built their houses? How did they solve the slope issue?