Hi, I’ve begun diving into tagging of apartment complexes in my city and one important thing to me is the ability to match apartment complex names to their street address. I noticed many discrepancies and I want to share my findings here and get some feedback on current preferred conventions at least for common scenarios in the US.
Finding current apartment complexes
Based on the wiki I presume all polygons defining an apartment complex should contain both tags residential=apartments and landuse=resdential. Most apartment complexes did not contain residential=apartments making it a bit harder to find:
| Criteria | Results |
|---|---|
| Multipolygon relations with residential=apartments | 153 |
| Ways with residential=apartments | 163 |
| Multipolygon relations landuse=resdential and minimum 1 polygon building=apartment | 20 |
| Ways landuse=resdential and minimum 1 polygon building=apartment | 59 |
| Multipolygon relations landuse=residential and no building=apartment but otherwise verified to be an apartment complex | 74 |
| Ways landuse=residential and no building=apartment but otherwise verified to be an apartment complex | 70 |
| Multipolygon relations without landuse=residential but otherwise verified to be an apartment complex | 1 |
| Ways relations without landuse=residential but otherwise verified to be an apartment complex | 10 |
I spot-checked several of the multipolygons and they don’t seem functionally different from areas and they make up 45% of my dataset. But I didn’t fully understand the nuance between the two (when counting areas made up of closed ways).
Should one of these always be preferred over the other for apartment complexes? Or are there situational reasons to pick one?
Finding addresses for complexes
This is where most of the data is lacking and I want to know how to improve it. I won’t differentiate the areas here:
| Criteria | Results |
|---|---|
| Area polygon has addr tags | 44 |
| At least one node inside the area has addr tags | 253 |
| Some node within 20m outside the area has addr tags for that complex | 4 |
| None of the above apply | 249 |
From what I can tell, addr tags shouldn’t apply to ways.
It seems when using a node, it should definitely be in the complex. For the 4 that don’t, they were very close outside.
For the ones where none apply, this means nominatim has no way to know the street address for an apartment complex which is named. Typically I find that the real address can be found close by, but is is interpolated. In many cases, the interpolation is poor which is a routing problem.
How should address nodes be handled for these cases? Should they be placed near defining entrance features?
Here’s a sample case:
This is one where the street address is still hard to match to the apartment complex name. There are multiple things at play here:
The highlighted part of the image shows a multipolygon where building=apartment and THAT has the name.
The node which contains the house number is NOT inside that multipolygon so we can’t easily link it to the name.
Both the building and the node are inside a way with landuse=residential (this is where I think the name should be).
The node isn’t close to the entrance but seems reasonably close to the outer way’s centroid.
The entrance road shown as “Ravella Drive” is in the outer way’s boundary: