| +/- wall=no
slight construction like a shed or balcony opened on one side at least or without foundation
This tag is always used in combination with building=* and is mainly used in France with data coming from the french land registry (cadastre). This is designating "slight constructions" like sheds or any construction with a roof and at least one side open or without foundations.
The french cadastre distinguishes two types of buildings :
- permanent buildings tied down (with foundations) and closed on all sides
- slight constructions like storage sheds or balconies or simple roofs which are open in one or more sides or are not fixed to the ground.
This tag has been proposed a while ago to translate this category from the french cadastre into OSM. The french community is open to discuss it and replace the old one by something new if a better tag is agreed by consensus.