How to draw and tag a building complex with sections of different building levels / storeys

I’m new to contributing to OSM data and want to learn how to so by improving the building complex Q1589788 (Way: 86421380 | OpenStreetMap).

This building consists of multiple connected/adjacent sections that build multiple patios. These sections have different building levels / storeys.

The existing data consist of multiple polygons (closed ways, not multipolygons) that do not match to the the sections of different building levels. These Polygons have a relation of type “set” that combines them to the entire building complex.

I already added to each building the adress - probably a bit premature.

So my questions to you are:

  1. How would you recommend to draw the building with its different building levels? A multipolygon does not work (i think) because the buildings share nodes (please excuse me if I misunderstood something here)
  2. If there are multiple buildings that together resemble one building complex, and they are combined with a “site” relation, where do you recommend to add the building’s address? (e.g. to each building and the site relation (if that is even possible), only to the site relation, only to the building/polygon that contains/is closest to the main entry)

If there is some kind of documentation - or discussion - that already answeres these questions, I’m happy to be pointed to it.


No, you don’t use =site for this. type=building can be used. If this is one whole structure , building= is drawn over the entire structure as outline (which needs to be a =multipolygon due to the holes). Each section is building:part= as part. Simple 3D Buildings - OpenStreetMap Wiki