code: def zone_height_min2max(idf, zonename, debug=False):
      
      zone = idf.getobject('ZONE', zonename)
      surfs = idf.idfobjects['BuildingSurface:Detailed'.upper()]
      zone_surfs = [s for s in surfs if s.Zone_Name == zone.Name]
      surf_xyzs = [eppy.function_helpers.getcoords(s) for s in zone_surfs]
      surf_xyzs = list(itertools.chain(*surf_xyzs))
      surf_zs = [z for x, y, z in surf_xyzs]
      topz = max(surf_zs)
      botz = min(surf_zs)
      height = topz - botz
      return height
docs: zone height = max-min