Sunlight and Architectural Design

Wilmari Claasen and Alessia Tami (University of Zurich) 

The Sun was instrumental in determining the layout of cities, houses, rooms, and windows, as its movement across the sky influenced lighting and temperature. Both Alberti and a German scholar, Walther Hermann Ryff, provided in their texts a set of guidelines to determine under what circumstances cities should be laid out and which cardinal direction.  In Bawkunst or The Art of Building (1582), Ryff claimed that cities built high up on a mountain or hill were most comfortable when they were oriented towards the rising Sun. Alberti gave instructions on how to account for ‘healthy’ and ‘unhealthy’ winds based on the belief that “the Winds are naturally inclined to follow the Sun.” Similarly to today, architects paid attention to sunlight when planning the layouts of houses and buildings in order to maximize interior light and regulate temperature. Alberti supported the ancient Greek and Roman practice of placing windows and porticos to the south, as they would receive “pure Sun and a clear Light,” while blocking direct sunlight during the summer and letting it in during the winter. He also suggested that the front of a house should receive ample sunlight so that it would look enticing and welcoming to guests, advancing an intriguing connection between hospitality and the Sun.