ARCHITECTURAL PANEL

PROBLEM TO BE SOLVED: To provide a panel which can effectively prevent intrusion of rainwater, etc., and reduce the fabrication cost, and provide a panel which is replaceable individually in any position after installation on a building. SOLUTION: Over the whole length, a fit groove 19 is formed in the side edge of one of the two architectural panels 10 to be installed adjoiningly, and at the side edge of the other architectural panel 10, a ridge 16 to be fitted in the groove 19 loosely with an inter-panel gap 11 reserved is formed over the whole length. A spacer 23 is provided for forming in an appropriate place in the inter-panel gap 11 an air passage 24 leading from the outer to the inner surface of the architectural panel 10 and restricting the relative movement in the extra-plane direction of the adjoining architectural panel 10 in the condition that the groove 19 is fitted on the ridge 16, and the space between the architectural panels 10 and an air-tight wall 2 is put in an isotropic pressure approx. equal to the atmospheric through the action of the air passage 24.