A floorplan is a subdivision of a rectangle into rectangular faces with horizontal and vertical line segments. Heuristic search algorithms are used to find desired floorplans in applications, including sheet-cutting, scheduling, and VLSI layout design. Representation of floorplan is critical in floorplan algorithms, because it determines the solution space searched by floorplan algorithms. In this paper, we show a surjective mapping from permutations to room-to-room floorplans. This mapping gives us a simple representation of room-to-room floorplans.