Hello Mateusz,

Thank you for your feedback, and sorry for closing the note without explanation. 

In France, a large proportion of the buildings on OSM come from imported cadastral data (provided as open data by the French government - example in our case: https://pikamap.fr/i/7342075.png), where balconies and other projections are often represented as separate parts of the main building. This explains the separation here and on many other buildings in the country. 

If you think it is not relevant to make the separation here, I volunteer to update the various buildings in the residence. 

What is your opinion? You have much more experience than I do.

PS: I would love to visit Poland, your country looks beautiful.