Sealing floor-to-ceiling windows and doors according to clinker?

Hello dear house construction forum,

unfortunately, our general contractor has also been affected; he informed us that he will probably have to file for insolvency. Some services are still outstanding at the construction site, but we are already living in the house. Just a heads-up...

Among other things, in my opinion, the proper sealing of the floor-to-ceiling windows and doors on the ground floor is still pending. The window installers have put a gray sheet metal in front of the windows, but in my view, the paths to the insulation layer on the left and right are open and should be closed. Despite serious flooding on the property (Lower Saxony in January), no water intrusion was noticeable, and no damp spots appeared near the windows/doors. Nevertheless, I am worried that the exterior wall insulation might get damp.

Of course, this is just my amateur opinion; maybe I am completely wrong. Considering that our general contractor certainly cannot commission anyone at the moment, the question is how we should proceed most sensibly here to retrofit a seal? Is that even possible? What would it look like, and what needs to be considered? We do not necessarily want to do it ourselves but rather hire a professional company. However, I like to have a rough idea of what needs to be done beforehand.

Maybe someone from the trade can give me 2-3 pieces of information about this? I have attached a few photos that describe the current condition.

Thank you all,
best regards from the North

The question is what it looks like "behind" the clinker. Usually, construction is done this way (perfectly illustrated from the internet):



If water penetrates, it only reaches the base insulation, which can handle water. Everything above that is protected. Unfortunately, it is not 100% clear how the sealing at the windows was done - just this panel attached or something else? At least it looks like "nothing was done" there.
If anything else is needed, ideally find a roofer. They do such sealing.

The question is what it looks like "behind" the clinker. Usually it is built like this (perfectly illustrated from the internet): If water penetrates, it only reaches the plinth insulation, which can handle water. Everything above that is protected. Unfortunately, it is not 100% clear how the sealing at the windows was done – just this board attached or something else? At least it looks like "nothing has been done" there. If anything else is needed, you should preferably find a roofer. They do such sealing.

Thank you very much for your input. I have a photo of how it looked before the windows came (here the bitumen sealing is clearly visible). Whether a separate sealing membrane was used, I do not know.

The general contractor last mentioned that another layer of liquid adhesive / bitumen will be applied to the sides so that the "insulations" are better protected.

The main contractor last mentioned that a layer of liquid adhesive / bitumen will be applied to the sides to better protect the "insulations"

If the main contractor himself says that, then have it done. From the photo, it doesn't look bad for a start. But the window and its profile should still be sealed.

I see something black in your last picture, which suggests that before the brick cladding was installed, the load-bearing wall construction was first sealed against moisture. The question is how the bricks were protected against rising damp.

Can you maybe ask the company for a detailed execution? Then they can better assist you with the further sealing work. I am also currently intensively dealing with sealing, but for a different construction method.