PURPOSE: To save the space of working area for maintaining goods in a factory building, reduce a construction cost of the building and to promote working efficiency at a narrow small site.

CONSTITUTION: A factory building is constituted of a main body building 1 and a subsidiary building 2 covering a working area 4 wherein goods in the main body building 1 are taken out horizontally to the outdoors and are handled. The subsidiary building 2 is equipped with a short stud 6 on the main body building 1 side and a long stud 7 opposed to the short stud 6, a wheel 8 mounted to the lower end of the short stud 6 is brought into contact with a rail 9 laid on a ridge 29 of the main body building 1 and are borne thereon, and a wheel 10 mounted to the lower end of the long stud 7 is brought into contact with a rail 11 laid on the ground and are borne thereon. A wall part 12 in the working area for taking goods in the main body building 1 in the subsidiary building 2 is removed or capable of opening and shutting, a good taking out device 5 for taking goods in the main body building 1 in the subsidiary building 2 is provided, and the subsidiary building 2 is moved along the main body building 1 in correspondence with a place taking out goods in the main body building 1.