User:Mateusz Konieczny/ruined building

This is only about tag for structure itself - tourism=attraction, name=* etc apply as usual.

(note that it is an incomplete draft not consulted with wider community so if someone has feedback it is welcome)

Some problems:

• there are cases where already mapped building was demolished and gone with no trace remaining but is still visible on aerial imagery
  • in such case it is useful to mark what is going on and temporarily preserve its geometry
  • note that it does not mean that intentionally mapping no longer existing buildings is helpful, use OpenHistoricalMap for that
• there are also cases of ruins remaining
  • note that this often overlaps "there was building here but is not anymore" but it is not the same

You can have cases where

• building used to exist and is gone without any trace
  • can be temporarily preserved to avoid people remapping it - but only temporarily, use OpenHistoricalMap for mapping such features
  • you can have cases where you have memorial plaque or other trace like this
• building used to exist and its ruins are still existing
  • ruins may be substantial or barely visible
• pile of rubble is in place, building never existed here
  • pile of rubble was moved
  • building was never constructed or construction was abandoned

Building

See building=* and building:use=*

Abandoned building

Abandoned building (was abandoned during construction and unfinished)

Still building, so building=* + abandoned=yes

abandoned:building=* is in some use but not recommended as it makes things more complicated without a good reason

Heavily damaged building

Building is ruined but is still a building - has roof and walls. building=* ruins=yes

Walls and skeleton of roof remains

Is it still building?

building=* ruins=yes

Roof is gone

building=* ruins=yes

Or is it not a building anymore?

Remaining standing wall/walls can be mapped with barrier=wall

Roof and walls are gone

Mappable remains of a building, but not a building=* anymore

Ruined remnants of a building.

so damaged that it is not a building anymore, pile of rubble, stumps of walls etc. are remaining - ruins:building=yes

Roof and walls are gone but cellars are remaining

?????????

Nothing left, still used as a name

place=locality

Nothing left, still a tourism attraction

tourism=attraction

Nothing left, still visible on high-quality aerial imagery

gone:building=* - is it making clear that no remains are present?

Only recently demolished buildings still visible on high-quality aerial imagery or otherwise highly likely to be accidentally mapped may be mapped this way.

"official database has building here" is not a valid reason to add geometries to OSM

• demolished:building=*/destroyed:building=*/razed:building=* - is unclear whether any remains or ruins are present - not recommended, but in wide use

Nothing left, no longer visible on high-quality aerial imagery

If it is no longer visible on aerial imagery expected to be used by mappers in a given area it can and should be deleted (if you want to map such buildings then OHM is a good place for that)

Intentionally build as ruins

Also known as sham ruins

building=sham_ruins

Just a single wall

barrier=wall + ???????????

Only foundation plate

Happens with abandoned or stopped construction.

man_made=foundation

Known underground remains, nothing whatsoever remains on surface

????????

Only memorial or information board remains

Map historic=memorial (or tag historic=monument or tourism=information or whatever else is currently present)

Note that this is not making former building mappable if it is gone.

Only memorial remains, memorial marks extend of a building

Wall in background marks extend of tower - it is not any form of remains

Still not a building but such wall can be mapped in addition to mapping memorial or be considered as a part of memorial.

Complex cases

In some cases part of former building may be a building=* part a ruins:building=* and part gone fully and not mappable at all.

List of tags which ideally would not be used

• building=collapsed - either it is not a building anymore because it collapsed (so building=* is wrong) or it has not collapsed so value is wrong
• building=ruins - the same
• building=damaged - use regular proper building tag. Damaged standing building constructed as temple is still building=temple - exact handling depends on stage of damage
• demolished:building=*/destroyed:building=*/razed:building=* - is unclear whether any remains or ruins are present

External links

• https://community.openstreetmap.org/t/do-we-have-building-for-existing-ruins-of-a-building/97276