Modern facade systems have to meet a diversity of functions. Through their influence on heating, cooling and lighting they effect the energy consumption of buildings to a large extent. While more transparent facades reduce the energy consumption for lighting, more cooling for the building is needed. Energy and comfort optimized building shells therefore require an intelligent control of sunlight. The company Karl Fischer Glasgroßhandlung developed in cooperation with the Institute for Solar Energy Research (ISFH) a self-regulating prismatic glazing system to reduce the summer energy impact.
It is based on prismatic micro-structured films which are inserted in the space between double-glazed windows. The additional sheet produces a glazing with the thermal properties of triple-glazed windows and saves even weight at the same time. The structure ensures that the direct radiation from the high summer sun is reflected completely, while the radiation will be allowed to pass freely at lower sun radiation. The "switching effect" occurs at an elevation angle of 40 to 50 degrees. During the project, the practical application of the glazing has been demonstrated.
