Evaluation of solar heat gain coefficient for solar-control glazings and shading devices

The determination of solar heat gain coefficient (SHGC) values for complex fenestration systems is required to evaluate building energy performance, to estimate peak electrical loads, and to ensure occupant comfort. In the past, simplified techniques have been used to calculate the values of SHGC for fenestration systems. As glazing systems that incorporate complex geometries become more common, test methods are required to evaluate these products and to aid in the development of new computational tools. Recently, a unique facility and test method for the experimental determination of SHGC values were developed and demonstrated for simple fenestration systems. The study described in this paper further applies this method to a variety of commercially available glazing and shading systems (e.g., heat-absorbing insulated glazing units (IGUs), reflective film and suspended film IGUs), and shading devices (i.e., slat blinds and shades). Testing was conducted in a solar simulator facility using a specially designed window calorimeter. The results of this study demonstrate the feasibility of the solar simulator-based test method for the evaluation of SHGC values for solar-control glazings and shading devices.