Splash guard around the house - tips

with the drainage pipe we are talking about the yellow perforated one I assume?

now it is lying there on the inside... but I wonder how the water now finds its way specifically through the small holes into the pipe and does not flow around it... which would then make the pipe superfluous, or if even only a part gets in there....

a layer with which material at the bottom?

everything from gravel up, so nice and coarse, everything works

And then a fleece on top of that and then the nice stones.

You can skip the fleece. You use it as a barrier if something might grow from below.

I wouldn't skip the fleece even if technically nothing can grow through from below, it still separates your two layers of rock and costs next to nothing anyway.

Drainage is of course the best solution. I just zoomed in on the picture again. As far as I can see, the back part (towards the house) is very rough and just residual concrete. I would try to remove the loose remnants. Maybe that will be enough for drainage, depending on how permeable the ground is here.

Yes, I'll take a look at that. Maybe also try to scrape away some of the concrete overhangs so that a bit more area is created for the insurance. Actually, there is still 1 meter of sand around the house from the foundation. So the excavation pit was made 1 meter larger all around than actually necessary and is a sand slab.

The things can withstand tank fire instead; towards the house, I would chisel away some of the concrete at the bottom again so that simply more water can seep in.