In this age of green imperatives, architects designing commercial and institutional structures are usually on the lookout for ways to add incrementally to a building’s overall energy efficiency. One of the many options available to them is to add shading devices to the exterior to reduce solar heat gain (SHG) through the building envelope, while creating elements of visual interest.
Exterior shading devices are among the structural considerations available to reduce the amount of direct solar rays impinging on the outside face of vision glass and entering conditioned space. When properly dimensioned, based on the latitude of the project site and orientation of the façades, such devices on south-, east- and west-facing walls shade windows or curtain wall expanses from the high summer sun to reduce cooling loads on HVAC systems, but admit the low-angle winter sunlight to supplement heating. In some cases, horizontal shading devices can also redirect natural daylight upward, increasing its penetration into occupied spaces and allowing reduced levels of artificial lighting. Horizontal shading devices are typically useful on south elevations, while vertical shading devices are well suited for east and west elevations.