There is a building in the process of being demolished (inside is gone, but the frame is still there). Eventually, it will be replaced by smaller buildings (not through renovation).
None of the “building:condition=” keywords seem to address this situation.
I had looked at the prefixes before posting. Demolished doesn’t seem to work unless the building is completely gone. Disused doesn’t work because it can no longer be easily reinstated. There doesn’t seem to be a tag for the middle ground. In other words, it would be nice for a “destruction” tag for something that is being actively destroyed.