|tunnel = building_passage|
|A tunnel passage that goes through/under a building, but is not inside the building itself.|
|Used on these elements|
|Tools for this tag|
The attribute tunnel=building_passage is used for ways that go through a building and have walls on both sides. They are rarely not on the ground level.
A building passage is strictly a tunnel, and is not a way that goes inside a building.
How to map
- The building and the way should have shared nodes at the entry and exit points of the building.
- The way is split at the entry and exit nodes and only the part covered by the building is tagged with tunnel=building_passage.
- The layer should be the same as the layer of the building, with the exception when several tunnels are passing on different levels. So if the building doesn't have a layer tag, the way should not have one either.
- There is no need to add covered=yes to tunnel=building_passage as all building_passage are considered covered and the additional tag does not add any meaning to the object.
When not to use
A building passage is a tunnel that goes through a building, but is not inside the building itself (see pictured examples). The walls at both sides (and the top) of the tunnel are considered outer walls of the building, which can have entrances that lead into it.
For ways that go inside a building (indoor mapping), the tags either highway=corridor, or highway=* + indoor=yes can be used.
Many fuel stations (amenity=fuel) have fuel pumps under a roof (building=roof) with no walls. Any service road that goes under the roof is not a building passage. Instead, the service road can be tagged covered=yes and the roof can be tagged layer=* to indicate that it is above the service road.
It is also not meant for ways that go through something else than a building.
3D model on OSM2World