Dry the basement, unusual arrangement

Hello, since my basement is damp, it needs to be dried out. Because the moisture comes from the street and I cannot connect a drainage system, the idea was to let the water infiltrate through gravel well before reaching the house, as the area directly next to the house is sealed. (Between the bitumen and the soil there is still 8cm of XPS). Does this make sense?

If you create a waterproofing according to DIN 18195-6, you do not need drainage or gravel in front of the house. It is important that you are not also dealing with rising damp, because then you will need an additional horizontal barrier in the lower area, otherwise you will not get your wall dry.

So the gravel stones wouldn't drain the water better in front of the house? I wanted to do the horizontal barrier from the inside with water glass...

But yes, you do need it with appropriate sealing. If you cannot install a drainage system, then the gravel strip is of little use to you, as the water will then accumulate in the gravel.

Ok, thought the water collects at the bottom and can seep below the foundation. Dug today and discovered: Sand on top (good) and clay (waterproof). Everything comes out and only the sand goes back in... Horizontal barrier with water glass ok or buy expensive special products?

Last question: There are 2 masonry light wells attached. Great thermal bridge :confused:. Should I treat them as well (brushing + primer + cement plaster P3 + bitumen + thermal insulation + studded foil) or does that make no sense? I am insulating against the surrounding soil (heat + moisture). Insulating against the air is somewhat more complicated: I would have to replace the concrete slab on the light well with a heat-resistant (e.g. Foamglas because of asphalt) thermal insulation board and insulate the light well from the inside (where the white Styrofoam would reflect the light better). Another light well is omitted due to various complexities... The electrical box is of course gone: