We have been recently discussing on the German ML about landuse=residential. In Germany many mappers were mapping subdivisions / neighbourhoods [1] with landuse=residential. This led to very rough landuse information, because in order to keep the (sometimes quite big) area as a whole they are forced to ignore landuses that don't fit.
I think that the information about these areas belongs to a distinct entity and would best fit into the "place"-namespace because I see them as subdivision of settlements (or more precise subdivisions of what we call "suburb" in OSM). If we could agree that the information about which areas as a whole form a distinct unit (part of a suburb) should go into the place tag, we would be more flexible when deciding where to apply landuse to. Part of the current discussion results from the mixing of namespaces: landuse is used to map settlement subdivisions which are IMHO defined by other properties (like morphology, history, culture, typology, ...) then just similar landuse. There is also areas which do combine different subareas with different landuses (impossible to map this with landuse-areas without either ignoring bigger parts of different use or loosing the entity as a whole). There are several questions in this context which are generally still open in OSM: 1. does the road belong to the landuse at its sides? -- as we don't (yet?) tag highway-areas for streets that are represented with a centre line this is an ongoing debate. For railways this is easier to decide because there will be landuse=railway along the tracks. Some mappers advocate to reuse street nodes others prefer to map these areas at the actual border of the parcels (or the estimation of the latter). Some pros and cons can be found here: http://wiki.openstreetmap.org/wiki/Talk:Key:landuse#How_to_map 2. What is the desired granularity for landuse? -- Shall landuse-areas be huge areas comprising several streets and blocks, or is it desirable to indicate the use of each lot if it is differing from the surrounding? Or could the landuse areas even go below single plot size? My personal answer on these questions is currently: To me a public road is a different landuse. Although it will not harm if we initially approximate the landuse with bigger areas comprising inner roads the ideal would be to have equal landuse in block-size units. This is most easily refinable and would also give the information of outer plot limits (adjacent to the road) so that you could infer the public land of the road. I would not go below the size of single plots (if there is not very good reason and a very big plot) and I would also still adhere to the rule of "predominant" use: if there is a building with offices in the ground floor and 3 storeys of apartments above this would be landuse=residential to me. If there was a whole plot with a factory inside a residential area I would tag this plot as landuse=industrial. Summed up the desired granularity I suggest to agree on is plot size for landuse (but we will not necessarily map all plots as distinct areas, it can also be bigger polygons). Cheers, Martin http://wiki.openstreetmap.org/wiki/Tag:landuse%3Dresidential http://wiki.openstreetmap.org/wiki/Land_use_and_areas_of_natural_land [1] Due to political, cultural and economic differences I am not sure if it makes sense to use the terms subdivisions / neighbourhoods because I guess the precise meaning is somehow different. _______________________________________________ Tagging mailing list Tagging@openstreetmap.org http://lists.openstreetmap.org/listinfo/tagging
