Window offers like day and night

What is "ABO"? Is that the "flex strip with ABO" or are we talking about an "ABO strip"? And does the plaster strip have anything to do with the tightness, or was just a regular plaster strip already installed by the window fitter?

But otherwise: see my list, they have pretty much messed up everything possible

Wow, a lot went wrong during the installation

What is "ABO"? Is that "flex tape with ABO" or are we talking about an "ABO strip"? And does the plaster strip have anything to do with the tightness, or did the window installer just simply install a regular plaster strip?

But otherwise: see my list, they have already messed up pretty much everything possible

Here look...

I am seeing this form for the first time, but that doesn’t have to mean anything. However, at first glance, the tape does not seem to be responsible for airtightness. How was the area below the door sealed? In any case, the tape is not visible there, and any kind of connection to the measure used there (the pink tape?!) is also not recognizable (dirt)?

A sealing strip for rendering should have some kind of recessed compression tape (positioned between the window and the visible part of the strip). If present, at least the visible gap at the blunt joint in the first picture should be sealed somehow. I would definitely check the corners carefully.

In general, with this system, I would pay close attention to the jamb being plastered carefully, since every crack there would simultaneously also have to represent a leak.

I’m seeing this for the first time in this form, but that doesn’t have to mean anything. However, at first glance, the tape does not appear to be responsible for airtightness. How was it sealed below the door? The tape is not visible there, and any kind of connection to the measure used there (the pink tape?!) is also not recognizable (dirt)?

A flush sealing strip should have some kind of recessed compressible tape (sits between the window and the visible part of the strip). If present, at least the visible gap at the butt joint in the first picture should somehow be closed. I would definitely check the corners carefully.

In general, with this system, I would pay close attention to the fact that the reveal is plastered with care, as any crack there would simultaneously have to represent a leak.

There is already a tape all around and everything is well glued. You can also see that the corners are better glued. I didn’t want to write it, but I went around every window with a candle to check for leaks.

There were no irregularities. I already know the quality of the plasterer’s work. I live in a multi-family house plastered by him. The exterior plastering is really well done and inside it’s a bit, well, so-so. It seems he lost interest a bit.

As cute as I find the candle experiment (I can relate to that from the bottom of my heart!), it was still useless. Airtightness is not about wind possibly blowing through here (the outer compression tape should prevent that), but about ensuring that warm indoor air does not penetrate the construction at this point.