Window panes, glass structures and electrochromic windows in buildings may be characterized by a number of solar radiation glazing factors, i.e. ultraviolet solar transmittance, visible solar transmittance, solar transmittance, solar material protection factor, solar skin protection factor, external visible solar reflectance, internal visible solar reflectance, solar reflectance, solar absorbance, emissivity, solar factor and colour rendering factor. Comparison of these solar quantities for different glass fabrications enables one to evaluate and thus select the most appropriate glass material or system for the specific buildings and applications. Measurements and calculations were carried out on various glass materials, including three electrochromic window devices, and several two-layer and three-layer window pane configurations.