PURPOSE: To make troublesome works unnecessary by a method wherein a unit, constituted of an air-conditioning device and air-conditioning air discharging ports connected to the device through ducts, is provided while the unit is attached to the upper side of a ceiling at site and the unit is connected to respective discharging ports in a living room and the like.

CONSTITUTION: An air-conditioning facility unit I is formed of upper girder beams 12, upper gable beams 13, lower girder beams 14, lower gable beams 15 and square pillars 11, whose end parts are welded to each other. An air- conditioning device 2 is attached to air-conditioning device mounting beams 16. The discharging ports 31, 32, 41, 51 are connected to the discharging ports 21 of the air-conditioning device through ducts 6 respectively. The unit I is attached to the upper side of the ceiling of a living room or the like and the discharging ports of the unit I are connected to the discharging ports of the air-conditioning device, provided at the ceiling of the living room or the like, through insertion or pipe fittings. According to this method, a plurality of discharging ports of the air-conditioning device can be connected to the unit I without necessitating any troublesome work.