PURPOSE: To conveniently carry out the reception of visitors by making the space between the outside and the inside open/close parts of a cylindrical body an internal passage, and by providing the inside of the room with seating parts, an information corner part, a communication facility, a housing part, an air- curtain mechanism, a dust removing means, or the like.

CONSTITUTION: The space between the outside open/close part 5 and the inside open/close part 6 that have been provided in a cylindrical body 3 is made to be an internal passage 7, and the inside of the body 3 is made to be the reception room of visitors. And on both sides of the body 3, connecting wings 4 are provided to enhance the workability to the building wall bodies. Then, in the inside of the body 3, seating parts 15, an information corner 17 having a monitor 16 and a communication facility, a housing part, an air-curtain mechanism of the outside open/close part 5, a dust removing means by means of slits 14 and air-discharge ports in the entrance of the internal passage 7, or the like are provided. Thus, the reception of visitors can be made comfortable.