Correct tagging method for buildings with roofs extending over sidewalks?

GuardedBear · 2024-08-24T13:08:47.422Z

What would be the best/proper way to tag this building/roof?

https://www.realcommercial.com.au/sold/property-107-dangar-street-armidale-nsw-2350-5014310231720×888 132 KB

For the purposes of this post, let’s call the brick part of the building the “main” part, and the roof over the sidewalk the “extended” part.

building=yes for the main part, and ignore the extended part (the map would show the sidewalk on the outside of the building)
building=yes for the combined main and extended parts (map would show sidewalk going through the building)
building=yes for the main part, and building=roof for the extended part (two separate but adjacent areas)
building=yes for the combined main and extended parts, but then building=roof for the extended part (an area within an area)
building=yes for the main part, and building:part=roof for the extended part (two separate but adjacent areas)
building=yes for the combined main and extended parts, but then building:part=roof for the extended part (an area within an area)
Any other, better options?

Note, the map currently uses option 1: Way: ‪Commonwealth Bank‬ (‪566960703‬) | OpenStreetMap

In the example above it maybe seems obvious that the extended part is indeed separate from the main part of the building, but perhaps that’s not always the case…? For example: https://cre.domainstatic.com.au/2018399943_2_1_230307_013647-w1600-h1200
Same question applies.

dieterdreist · 2024-08-24T13:52:44.000Z

I would do variant three: 2 separate buildings, one a roof. If you want you can create an attached_to role in a “provider” relation or something like this

The main building should probably remain building=retail and not yes, as option 3 suggests.

If the sidewalk is mapped you can add covered=yes to the part under the roof

Tjuro · 2024-08-24T15:13:51.149Z

Would go for option 3 or 1.

And then tag the sidewalk with covered=yes.

Kovoschiz · 2024-08-24T15:57:17.033Z

You can draw the footway=sidewalk + covered=yes first
It’s not that bad initially. But it overlaps with 1 if someone draws the footway=sidewalk , so 1 is easier.
This doesn’t seem valid
Please remember you need to create a type=building to relate the outline building= with the part building:part=roof that’s outside
Please remember you need to create a building:part=commercial to cover the rest

3 is the simplest. But why do you say “seems obvious that the extended part is indeed separate from the main part”? If anything, this is attached as a cantilever. On the contrary, the other covered=arcade case is partially supported by its own, although such a layout may be a building:part=balcony .

ManuelB701 · 2024-08-24T19:22:16.187Z

I’d go either with 3 (easy) or 5 (more complex) alongside mapping the ways below as covered=yes depinding on how wide the roof is.

ManuelB701 · 2024-08-24T19:30:10.436Z

Kovoschiz:

This doesn’t seem valid

I’ve seen Not that I would it, though, since such roofs are usually part of a building.

Kovoschiz:

Please remember you need to create a building:part=commercial to cover the rest

First time I’ve heard this kind of building part mapping and feels overkill to me. AFAIK the building type of the part is usually inherited by the outline and the need to do this is fairly rare, one where no primary use is really prominent, for example (similar to why roof:shape=many is IMO only necessary when no kind of roof shape is really prominent).

Kovoschiz · 2024-08-24T21:53:16.007Z

That’s not my intent. The building= needs to be completely covered by building:part= . Option 6 didn’t mention this.
But still, having building:part=commercial inside building=commercial is useful to confirm this has the main function. building:part=yes may be used for anything. You can’t be sure.