Design and Performance Evaluation of Differentiated Daylighting Glazing Systems by Scale Model Measurements

Growing use of transparent glass facades with metal frames is popularly detected in modern building practices. Besides aesthetics and visual contact to outdoors, however, the designers, must inevitably see a fact that the use of clear glass on the whole fac;ade might cause a sort ofvisual problem due to the harness of direct sun and brighter sky surface than affordable. They should be filtered in optical way or bounced properly in the architectural. Photometric glasses with various transmittances for the glass walls can be issued for the situation. Additionally, a window might be differentiated into its component parts, the higher daylight window and the lower view window applied with various transmittances. This might reduce the severe contrast ratio between the interior surfaces of the space and the brighter exterior view, with holding the higher performance of daylighting. This paper deals with performance data related to the impact of various transmittal-glazing materials for the design strategies of differentiated window systems in terms of daylighting. A series of scale model measurements was carried out with the fundamental configuration of a commonly used all-glass facades and compared with the proposed new. Some experimental performance index was issued for the better expression of the need of natural lighting.