When I search for “Langezijds” on Nominatim I get no results. However, I would expect to find the Langezijds university building (Way: Langezijds (1173799338) | OpenStreetMap) which houses the Faculty of Geo-Information Science and Earth Observation (ITC). It seems also that OSM Carto does not render the name of this building (part), although that may be a different matter.
This seems to be because the parent (enclosing) building has no name tag, while the building:part=university elements within it do. Looking at this Nominatim issue it seems that the current tagging might be considered “mistagging”, but honestly I find the OSM wiki pages on buildings complex and confusing, so alternatives are not obvious to me.
From reading similar topics I can think of several courses of action:
Leave it alone, tagging is fine and Nominatim, Carto etc. interpretation is their own
Make each building:part its own building with corresponding name tag?
Add the building name into the addr: tags somehow?
An additional remark: Searching for Langezijds on OrganicMaps does indeed find this university building, but it fails if given as an address (e.g. “Langezijds 8”, “8, Langezijds” etc). This is unfortunate, since the building is often given instead of the street name for many materials listing addresses. While this could be a feature request to the OrganicMaps developers, it is unclear to me whether it is not an issue with the tagging itself (i.e. the address nodes should contain the building name).
I find the tagging to be correct. The fact that Nominatim doesn’t find it, is unfortunate, but you can always open a bug report to get this fixed. Or, of course, a PR, so it’s even less work.
If this is commonly used. you could consider using addr:housename=Langezijds, but I’m not sure if this is correct, since it’s probably not part of the official address from what I understood. I have no experience with housenames like this. In Germany, if someone was referring to “XXX house 7”, I would be looking for an entrance #7 or something similar, but that might be different in the Netherlands. Try it
I kind of agree with the argument made in that issue: The building:part key was invented for 3d mapping. So if someone were to map your building in 3d, they would be forced to break the two current parts down into a larger number of smaller parts with different heights, different facade materials and so on. (A bit like you can’t expect there to be exactly 1 OSM object for an entire named street because the street might branch, change number of lanes, have sections with different maxspeeds etc.)
What this means is that building:part really isn’t a great fit for the “section of a building that is known under a distinct name” use case.
Whatever the original use case it’s a perfectly good tag to describe part of the building and if that part of the building has a name then that’s the logical object to put it on.
Unless you know of a better simple indoor tagging alternative?
Langezijds is a separate building with an independent history, that only happens to share a wall with the adjacent building. I think mapping the whole complex as a single building was an error from the outset.
