BlenderBIM doesn't "import a building" BIM is a method of detailing a house. You export it to something like IFC and then share it. For example if you do design in Blender, but the plumber uses Revit you use IFC to share between the two programs. The plumber adds the piping to the plan, and exports it for you and then you now have a all of the plumbing required.
You can then export it using BIM to a schedule which will say we need 45 90deg corners, 20 10" pipes, etc...