Convert Watertight Mesh to Solid

[Yna_Db]

No merit, we just played somewhat with that recently

Atrium roof: Grouping points for adaptive components

aaand when I see @Thomas_Mahon answer, maybe this could suffice. link dwg in Revit create toposurface from import [image] There will probably be some edging problems due to the outer perimeter of you geometry, but possibly some split toposurfaces could do?