PURPOSE: To easily perform work even by a single person in a short time by providing lift devices for automatically lifting each panel and detecting sensors for detecting a joint of a surface material of each panel to stop driving of the lift device.

CONSTITUTION: A base table 2, on which a plurality of panels 1... can be arranged transversely, is provided, and sensors 6 for detecting joints 5 of a tile or the like, formed on a surface material 4 of the panel 1, are formed in an equal pitch to lift devices 3 while providing the lift devices 3, for automatically lifting each panel 1 by a motor or the like, in the base table 2. In the detecting sensor 6 formed of a reflecting phototube, the joint 5 is detected by a change of reflected light by irradiating the surface material 4 with light, and when the joint is detected, driving of the lift device 3 is stopped. The base table 2 is raised by a raising machine 7, by setting the panel 1 to the base table 2 in a horizontal condition, to lift the panel by actuating the lift device 3, and its driving is stopped when the joint 5 is detected by the detecting sensor 6.