Orientation Specific Solar Control

During the postwar era, and before the universal adoption of air-conditioning in the United States, leading architects participated in the design of solar houses and the use of solar shading devices as means of controlling heat gain. Much of the progress in solar design in residential designs was due to flexibility in shaping plan arrangements and building volumes to relate glazing exposure to different program elements and site conditions. Solar homes were more expensive than non-solar homes due to the use of insulated glass to mitigate large glazed areas. Thermal storage typically in the form of water tanks also added to costs. Central air and through-wall systems were cheaper to install and offered the advantage of greater control and more rapid cooling than passive systems.

Since non-single family buildings are less flexible and more expensive than independent residences, there are fewer examples of large postwar buildings shaped to mitigate and harvest solar energy. However, solar shading devices were applied to buildings with varying degrees of effectiveness. Successful examples exist, for instance, Richard Neutra’s design for the Northwestern Mutual Fire Insurance building (1951) in Los Angeles utilizes horizontal shading devices on the southern side and operable vertical shading devices on the east face of the building. Most shading devices from the postwar era, and today, are horizontal regardless of orientation.

Despite technological advances within the last seventy years, the paucity of particular treatments of building orientations and the generic use of shading devices is striking. This paper focuses on shifts in the architecture of Louis Kahn across four projects designed within a short period of time to demonstrate how the culture of shading devices shifted around 1950 leading to a steep decline in use of solar shading devices. By investigating four cases including the Pennsylvania Solar House prototype, the Weiss Residence, the Philadelphia Psychological Hospital Radbill addition and Yale Art Gallery addition, the author seeks to demonstrate how shading devices entered and left an architect’s repertoire. Another goal is to relate these factors to the current paucity of appropriately positioned solar shading devices on buildings.