From OpenStreetMap Wiki
If it's not clear what type a historic building has, it can be tagged as a generic building.
does not make much sense to me.
- thanks for reaching out. an example might be a preserved kiln - it's a building, it's of a historic interest, but it does not seem to match any of the other values. do you think adding a kiln as an example in the description would be useful ? i'm not sure about creating a full page for it yet. --Richlv (talk) 18:30, 7 May 2014 (UTC)