Okay, we have two separate issues here. It sounds to me like the building as a whole would be tagged `building=dormitory` with the name of the building (assuming it has only one) 1) Separate entrances can be tagged with `building=entrance` and `entrance=` (the wiki encourages you to use `entrance`, `entrance` alone, but I prefer to have `building=entrance` too). Notes or `amenity` nodes can be used to indicate which is which. 2) If you want to indicate the structural "shape" of the building, now, it gets more complicated. The way I understand the `building:part=` documentation (which seems to me like ), these are added "on top" of the `building=` tag and receive the descriptive tags (e.g. `height` and `building:levels`), with `building:parts=` added to the same way as the main `building=dormitory` to tell whether the spli is horizontal or vertical. If you do use `building=part`, then each separate part can get `amenity` tags.

Okay, we have two separate issues here. It sounds to me like the building as a whole would be tagged `building=dormitory` with the name of the building (assuming it has only one) 1) Separate entrances can be tagged with `building=entrance` and `entrance=` (the wiki encourages you to use `entrance`, but I prefer to have `building=entrance` too). Notes or `amenity` nodes can be used to indicate which is which. 2) If you want to indicate the structural "shape" of the building, now, it gets more complicated. The way I understand the `building:part=` documentation (which seems to me like ), these are added "on top" of the `building=` tag and receive the descriptive tags (e.g. `height` and `building:levels`), with `building:parts=` added to the same way as the main `building=dormitory` to tell whether the spli is horizontal or vertical. If you do use `building=part`, then each separate part can get `amenity` tags.