Day light is becoming an increasingly important factor in the process of developing buildings that are energy-efficient and user-friendly. In architecture, natural light represents an essential design factor.

With good day lighting, changes in the natural light level during the day, as well as variations in light due to weather conditions and the seasons, can be percieved at the workplace. This maintains the connection to the external world. Well day lighted rooms with pleasant natural-light atmospheres significantly enhance the sense of personal well-being.

Besides, this intensified day lighting generally yields a decreased use of artificial light. However, since the availability of natural light is characterized by strong seasonal variations at our latitudes, a strategy that strives to exploit day light to the maximum possible extent must also consider adequately the aspects of solar shading and glare protection. The objective is to develop solutions, which are compatible with the use of the building while taking local conditions and structural factors into account. A ingenious day light planning begins in the early conceptual design stage, in order to allow the design freedom to be fully exploited. During subsequent conceptual and detailed design stages, various day light systems or strategies for rational natural lighting can be investigated and evaluated in terms of their functionality and efficiency.