ANALISYS: Shading devices technologies for transparent buildings envelope

The evolution of the environmental control techniques combined with the support of detailed computational software inquire to the designer a careful choice of shading devices in the building design, in order to ensure the consumption control during summer times and to provide comfort for the occupants. Generally speaking, a screening system can be applied to the right-angle frame of the entire building or a portion of it, adding also a value to the renewal of the façade design, so that their application allows a new perception into existing buildings. A well-conceived shading device must be able to maximize heat gains in winter conditions and to control the radiant heat in summer conditions, as well as to improve visual and acoustic comfort of the interior. All the sun protection systems installed in front, or on the outside of the frame, without making the same body, are external sunscreens, by definition. Solar shading device can be defined as a screen attached to the outside of the wall that consists of several horizontal or vertical elements with the function of sun radiant energy mitigation. Outdoor sunscreen solutions bring higher added value both in terms of architecture and in terms of economic performance. The external shields, much more effective than internal ones, are usually more expensive and subject to maintenance, since they are permanently exposed to atmospheric agents. The type of material of screen components plays a fundamental role. The blinds elements are mostly made out of extruded aluminum or galvanized steel and painted. There are also brise-soleil made out of other materials such as wood, brick, PVC, and copper. Whatever the material employed is, the device must ensure adequate operability and aesthetic value over time; in this regard, metals, properly treated and painted, have effectively replaced wood, more prone to deterioration. The selection of external shielding components should take into account the outdoor weather conditions and the device wind resistance, since, under high wind loads, the system can suffer major damages.