The application of selective coatings in glazings allows a more efficient management of heating and cooling loads of a building. The solar, visible and UV transmittance are three of the most import parameters for the evaluation of glazing lighting and energy performance, which depends significantly on the rays angle of incidence. The goal of the research is to define the transmittance of glazing systems equipped with selective coatings, varying the rays angle of incidence. A ray tracing simulation code is adopted, previously validated through an experimental campaign conducted with a spectrophotometer. The ray tracing simulations were useful to provide good estimations of the optical properties of coated double sheet glasses, in any irradiation condition, once the properties of the single components are measured.