Edit for quick post: While standalone staircases on floors other than ground are looking ok. ground floor staircases are hindered by the wallplans. Solution: Please, let us build a standalone staircase, on ground floor, as a special case of "floor" without the need of building walls. the tile will be part of the building. Name the structure "external staircase", and once built, remove external wall plans aka consider the tile built. as a special case for ground floor. all other floors work as should. then we could have external staircases. from wiki:(this could be groundfloor) it will make designs so much better. and beautifull. and will give meaning to standalone staircase.