Seal the base area at earth formwork and rain gutter

Good day,
I have a building without a basement, built in 1985.
The floor slab consists of waterproof concrete, the exterior walls are made of Poroton.

Unfortunately, the Poroton bricks protrude beyond the floor slab in some places, causing moisture to rise despite the bitumen barrier between the floor slab and the first row of bricks.

I actually wanted to seal this with a bitumen coating, but the floor slab is not smoothly shuttered in one place; instead, it was cast as earth formwork and is therefore very uneven.

In another place, the floor slab was apparently not thick enough (?), and cut Poroton bricks were used to build up (below ground level).


Do I have to pretreat and smooth this area somehow, e.g., with a cement mix? Or can I simply apply the bitumen compound thickly here and consider the matter "done"?

Furthermore, I wonder how to seal at a spot where an under-plaster rainwater pipe exits at the base area.


I hope I was able to clearly describe my problem areas.

Thank you very much for the help

Thorsten