Hi, I want to extract buildings’ polygons using Overpass. I can get a building’s name using [‘tags’][‘name’], but how can I get the type of the building, e.g. whether it is a restaurant, or a shopping mall?
Well, you cannot be sure that any POI tags are also mapped on the building outline, when there is a POI in that building.
Because you can tag a POI as a closed way OR a single node. See http://wiki.openstreetmap.org/wiki/Elements
So I recommend to do an overpass query not only for buildings, but for POIs, like amenity=* or shop=* etc.
Note that in most cases in the UK, buildings with shops in them are mixed use and it is actually wrong to tag the building with shop=*. The ground floor may be a a shop, but the other floors may be offices, or residential flats.
The actual building type is in the building=* tag, but you mainly find that that is “yes”>
Thanks all for the information!