Role of Façade Elements in Daylight Control for Improving the Quality of Indoor Environment

The issue of maximum utilization of natural light is of a great importance in modern architecture. Natural light is proven to play major roles not only in the overall quality of indoor environment, but also in minimizing energy consumption, and helping physical/psychological health of occupants. However, modern mass constructions struggle with lack of space, windows and access to sunlight. Contemporary architecture, specifically in developing countries relies on artificial lighting rather than daylighting. As a matter of fact, daylight utilization can be assumed as a concept with two contradictory sides. In one perspective, daylight utilization enhances the quality of indoor environment and decreases energy consumption for artificial lighting; but alternatively, direct sunlight particularly in hot climates leads to glare, visual and thermal discomfort. These issues can be addressed by innovative daylight utilization and control strategies as well as lessons learnt from traditional architecture. This study aims at identifying daylighting strategies and more specifically facade elements for daylight utilization and control. To fulfill this aim, the merits of daylight utilization in architecture are firstly analyzed. It is shown that efficient daylight utilization and control significantly improves the quality of indoor environment from different aspects. Having highlighted these aspects, facade elements for daylight utilization and control are described. Then, case studies in Iranian traditional and contemporary architecture are investigated to identify how different façade elements and their arrangements for daylighting in residential buildings contribute to the quality of indoor environment. Iranian traditional architecture is well known for its sustainability and therefore three traditional cases are picked from hot climate regions iv in Iran as illustrative cases. The contemporary case studies are featured residential buildings with innovative designs. The results of the case studies uncover valuable clues about how façade elements and design strategies for daylighting enhances the quality of indoor environment. Finally, recommendations for daylighting are given for the designers to integrate lessons learnt from traditional architecture in modern designs. Keywords: Daylight utilization, Daylight control, Facade elements, Indoor Environment, Iranian contemporary architecture, Iranian traditional architecture.