COMPUTER-OPTIMISED SHADING DESIGN

Computer modeling and simulation has a relatively long history in the prediction of thermal and lighting performance in buildings. As the input requirements of such analysis are quite extensive, these areas tend to be addressed computationally only in the latter stages of the design process, usually as a validation of decisions already made. However a detailed computation of incident solar radiation requires much less detailed input and has many applications much earlier in the process. Of significant importance is its potential as a tool to drive design decision-making and as a form generator in its own right. This paper demonstrates how solar position calculations can be used to automatically generate quite complex optimised shading devices and quickly determine the solar envelope of developments given even the most stringent of overshadowing restrictions. The limitations of the precise geometric calculation of shading shape are discussed and an alternate approach to handling more complex situations using ray-tracing techniques is presented. These methodologies have been integrated into an interactive conceptual design tool called ECOTEC