I think it should be possible to place the chimney's on flooring and basic shapes instead of just roofs. It would help everyone that wants the detail of a chimney and the smoke even if they're building a house fully out of basic shapes or something. It's also because some people build a pop out from the house out of basic shapes and they want a chimney there but they can't place it because it's smaller than 1 full grid in width and maybe not tall enough either.