A Review of Optical Properties of Shading Devices
INTRODUCTION The optical properties of shading devices have a decisive impact upon the thermal and daylighting performance of perimeter spaces. It is therefore surprising that, currently, there is no widely recognized procedure for measuring or calculating shading optical properties (ISO 15099, 2003). Consequently, many shading manufacturers provide limited or incomplete technical specifications of the optical and thermal properties of their products. The data provided tends to be integral values that cannot satisfactorily resolve the often strong angular dependency of shading devices. As a result, the products cannot be reliably modelled in energy simulation tools since the software engines usually import sets of properties from existing databases (WINDOW 5/THERM, 2003).