- Buildings Guide
- Policy Guide
- Appliances Guide
Provision of shading in buildings and the choice of colour for its surfaces is one of the initial priorities that have to be considered in the early stages of the design. Blocking/allowing the sun (and thus reducing/increasing the solar heat gain) before it reaches the envelope and reflecting large parts of that solar energy that cannot be blocked both have a considerable effect on the thermal performance of a building, its energy requirements and the thermal comfort of its occupants. Shading devices like awnings and louvers can reduce solar heat gain by 65% on equator facing facades and up to 80% on East and West facades (Harvey, 2006). A shaded window transmits approximately depending on latitude longitude and orientation only a third as much heat as an unshaded window.
The very purpose of constructing a shelter or a building is to offer protection from natural elements like sun, rain and wind. However, special emphasis is required on shading to precisely control the solar radiation that enters into the building through fenestrations in the facade. While solar gain is typically required in cold climates, it is to be completely avoided in the hot climates. Various types of shading elements like overhangs, blinds, pergolas etc. can be seen in various building typologies. Increasing internal loads in modern buildings and increase in glazing area in the façade makes any amount of solar radiation undesirable and thus calls for special attention to design of shading elements.
Shading for fenestrations in buildings is typically done through shading devices such as fixed or movable shades, awnings, louvers, internal and external blinds etc. In hot climate opaque surfaces also required shading using techniques such as self-shading, overshadowing, vegetation etc. Shading devices are integrated into the building structure, designed as a part of the building’s elevation, or added post construction. Movable shades can either be controlled manually or controlled automatically. The following are some type of most commonly used shading devices.