Sealing the exterior facade after land filling

Hello dear forum members,

after the house here has been largely completed, my partner and I would now like to start with the outdoor areas and work.

According to the original plan, we want to raise the ground level of the property a bit. The landscape gardener we hired would simply raise the ground after consultation and, if necessary, pave flush with the brick wall. However, I am unsure whether we should waterproof the exterior wall beforehand. It is a double-shell masonry with an air layer and insulation.
Unlike in the original plan, the landscape gardener suggested paving the terrace at ground level. However, this would result in the ventilation slots being closed.

As you might have already gathered from the explanations, I am a total layman on the subject. However, I fear that we might be creating problems that we do not want. Do you have any tips on what to pay attention to and what to avoid at all costs? Would a gravel layer reduce the problem of the covered ventilation slots? Is waterproofing of the masonry necessary and if so, in what form?

Many, many thanks to you already!

Ps: I have attached a picture of the future exits to the terrace. Hopefully, the ventilation slots can be seen. The paving should be done at ground level as described above.

I am almost certain that you urgently need to think about the sealing at the shown location first.

If there is not a second sealing layer (of course no longer visible in the picture) behind it, the sealing shown IN FRONT of the brick (in my layman’s opinion) is completely wrong and therefore not functioning properly.

Search for "Der vergessene Anschluss". This topic is dealt with intensively there, as it is a common but unfortunately serious mistake.

Otherwise: Personally, I would then retrofit at least higher placed ventilation options (clear the joints) and have the paved strips around the house laid with a clear slope away from the house. Of course, there should also be a dimpled membrane between the paving and the brick (which you do not have to see...). As always, without guarantee of correctness ;-)

Hello , thank you very much for your quick response. The sealing visible in the photo is indeed only the second layer; the actual sealing is behind it. I cannot say whether it was properly installed, but at least it was not criticized by the inspector at the time.

The other explanations are also very helpful, thank you. The father-in-law had also suggested installing a dimpled membrane (however, including a bitumen coating, which others advise against). I will place the ventilation slots higher; I have read that a few times now, but I was not sure if I could just do that without further ado.