To vary the plan of the whole room.

A housing room main body 10 is installed on a floor surface 100 in the room. The main body 10 is composed of frames 11 to 14 to make a framework and mounts a surrounding wall, which is not shown in the figure, on an outer surface. The bottom surface of the main body 10 is in rolling contact with the surface 100 by a roller 20 mounted to the bottom surface of the main body 10. A guide rail 30 is fixed along the cross line of the a wall surface 200 and the surface 100 and sliders 40 freely slidable with respect to this guide rail 30 are mounted at the lower part of the main body 10 in the state of projecting toward a side. The main body 10 can move along the guide rail 30 while supporting its load by the roller 20.