Given a 3D non-slicing floorplan, based on the property of packing-driven ordering in the floorplan, all the blocks can be ordered as a block list. Furthermore, according to the maintenance of a dynamic sliceable floorplan, any 3D non-slicing floorplan can be transformed into a 3D slicing floorplan by shifting the related blocks to minimize the final floorplan volume. The experimental results show the proposed approach is more effective than the modified FTP-1 algorithm. Clearly, the proposed approach can serve as a post-processing phase for other non-slicing floorplan algorithms.