I know this is a tradition in Lithuania, when the building main structure is done, the builders hang a decoration made of branches and etc, this is done on [small](https://sa.lt/wp-content/uploads/2019/12/Untitled-1.jpg) and [large](https://scontent.fvno5-1.fna.fbcdn.net/v/t1.6435-9/95589255_2612944188953240_2121987137288011776_n.jpg?_nc_cat=108&ccb=1-7&_nc_sid=5f2048&_nc_ohc=beOj1L8yy4AAX83IP3i&_nc_ht=scontent.fvno5-1.fna&oh=00_AfCF8-OcXuH3DzqDY6gmLbbxM9MXk3mzXx_HP5HUfHvxZw&oe=6614FF87) constructions.
I also saw this post about Notre Dame https://www.reddit.com/r/europe/comments/1ban5p9/rebuilding_the_notre_dame/ that also had some kind of decoration.
So would that be something that happens in your region too?