Generating 3d building from 2d floor plan,Creating a 3d enviorment with a floorplan

Has anybody ever supplied a 2d floor plan and generated an indoor 3d environment? if yes what did you do rather than extracting the useful t$$anonymous$$ng manually such as walls?

Also, what did you do to ac$$anonymous$$eve it and make it to real-world scale?

Finally, how did you tackle multiple floors?

Reason for t$$anonymous$$s question I'm trying to augment indoor navigation but would like to skip the manual work of building each wall manually