Protect windows during the construction phase, but how?

Google simply search for self-adhesive screen protector film. Use a branded product. I've heard stories where the printing has rubbed off... But it does not provide protection against severe mechanical impact.

can you recommend a specific product (otherwise also via private message, in case that would be advertising)? Thanks!

Take the blue glass protective film that is available in all kinds of shops. It is good and inexpensive. Peel off a piece once a week and check if everything is still in order. At the latest after 6-8 weeks, I would consider changing it for safety reasons. Everything else is professional level and should be adjusted to the respective frames, etc. It then also becomes significantly more expensive.

If the topic is still of interest: I will protect the windows at my place with a plastic bag that is pulled over the window sash. I got this tip from acquaintances and saw it on a house in our neighborhood.

The craftsmen go crazy when they have to work in the dark because the windows are masked off. In my experience, the frames suffer the most, which is why I would only protect those.

After such a long time, dropping by again.

The craftsmen freak out when they have to work in the dark because the windows are taped over.
From my experience, the frames get hit the most, which is why I would only protect those.

So the foil is transparent, as far as I have seen. So enough light comes through, and yes, the frames get hit the most; a thin foil doesn’t help if someone hits it with an edge. For me, the foil is interesting because the coarse dirt simply does not get on the window surface, and cleaning later goes much faster.

See you in a few weeks, building a house takes up a lot of time :)