Waste on the construction site - What is tolerable?

That sounds good too. If you have such a constellation, the prerequisites also seem really good. Unfortunately, we were not blessed to find a well-established team. We spoke with 4-5 architects, all of whom saw problems at all with finding sufficient / adequate craftsmen. What kind of starting point is that?

Although with the knowledge of today, I would have searched even longer and more intensively for such a solution.

Unfortunately, that is the case today. My architect also knows them all from school and said I should consider myself lucky to be able to build with such a constellation. I see it with my neighbors; they all build with general contractors who promised them who knows what and even when it is urgent, no one answers the phone or they are kept waiting for several days. Really annoying.

Do not generalize. My GU was okay, those who have GUS here from Rendsburg and Neumünster are also well served, diagonally opposite GU from Plön very decent.

Don't generalize. My general contractor (GU) was okay, those who have GUs from Rendsburg and Neumünster here are also well served, diagonally opposite GU from Plön very decent.

That may be true, but as a layperson you first have to find them and not be blinded by any salespeople. My neighbors next to our rental apartment, directly behind the fence, started at the beginning of June. If I had to sum it up, I would say they had 50% of the time just standstill so that no one worked on the construction. They also had the GU in focus. Luckily we decided otherwise. Yes, I am not a fan of GUs, that's true. However, this is due to bad experiences of others during construction and our experience in the tender phase.

So it also blew in for you until the painter came? I can't imagine that such a "window sealing" is normal.

What do you specifically say about the expert's text that I quoted? Are you not of his opinion at any point?

Actually, the window should be sealed with Sigaband during installation.
The painting company did that for us (we were taken care of with many small tasks that weren't necessarily typical, as they were almost always on the construction site)
The site manager personally taped off some places.

The painter applies acrylic around the windowsills when he paints the reveal.

The windows were sealed after installation before the windowsills were installed.

That was the case for us.

The windows were airtight after installation before the installation of the window sills.

Did you also check this using a blower door test or is there another way to verify it?

We had the first Blower Door Test after window installation, before exterior plaster, interior construction, and screed.

No idea if there is another option.

Siga sticks strongly. The tape pressed on neatly without folds can only be airtight.