External shading devices are essential environmental controls that either obviate or greatly reduce the need for mechanical heating and cooling to maintain thermal comfort inside buildings, by controlling heat gain through openings. Along with glazing type and size of the fenestration, shading devices are equally important in limiting heat gain from outside through radiation. External shading devices can thus be used as an essential solution for achieving energy efficiency.

Orientation of an opening and by extension, solar radiation incident on it, is the single most important factor in the design of its external shading devices.  Impact of seasonal variation in the sun path is linked to the orientation. Sun path is at a low angle during the winter season in the southern hemisphere. In summer, sun path is at a high.

The HPI d-school Building has a unique shading strategy with roof overhangs, balconies and expanded metal mesh. The latter provides a dynamic shading effect with the use of a fixed device due to the interplay of the angular perforations on the device vs the sun angles throughout the day and year.