Windowpane) never replaceable again

Unfortunately, I cannot imagine that either. Recently, two panes were replaced for us because they were delivered with scratches/stains. The window fitter loosened the inner frame (which holds the pane) and was then able to simply take out the pane.

So, roughly, this also applies to window glass replacement. This usually takes about 30 minutes; in the case of your TH window, probably longer, because the pane cannot be removed from the front directly. Work has to be done from the ground floor and attic (or upper floor, depending on which type of house you had built).

So no defect – you approved the execution plans and your architect was entitled to assume that you are capable of thinking.

Rhenish regards

As I said, I am probably capable of thinking, but as a planner one could point out such pitfalls, or are you also of the opinion, hopefully the client signs the contract, I don't care what comes later? Most people build one house in their lifetime and now you want to say that someone who otherwise has nothing to do with construction planning must still recognize every pitfall on paper? Then I wonder why even trained planners and architects make so many planning mistakes? Then I wouldn't let you do planning!

Unfortunately, I also can't imagine that. Recently, two panes were replaced for us because they were delivered with scratches/stains. The window fitter loosened the inner frame (which holds the pane) and was then able to simply take out the pane.

Yes, normally this is not a problem, but you probably can't take it out forwards because, as mentioned, the stairway is probably in the way.

Piece down, then diagonally and out.

I would just ask the window installer what he thinks about it.

No planner or window maker is crazy enough to install a window that cannot be replaced later.

I would not sign that