What are the considerations when designing a solar shading system?

The movement toward sustainable building designs is being driven largely by environmentally-conscious building owners and/or their prospective tenants. As these owners and their consultants weigh up their design objectives and alternatives, they often find that exterior solar shading controls are an ideal part of the "green" solution for their buildings.

Exterior solar shading can dramatically reduce the air conditioning loads caused by the solar shading’s radiation penetrating the building’s windows. Indeed, some form of exterior solar shading is now part of the country's prescriptive design requirements. In addition to energy savings through reduced cooling loads, exterior solar shading can enhance a building’s appearance, as well as provide controlled daylight and reduced glare.

Shading system block a certain amount of the solar radiation from entering the building. They are ideally designed to maximize natural daylight while controlling solar heat gain and glare. We offer a wide range of solar shading products, from static aluminium to fully automated louvres covered with electricity-generating photovoltaic cells.

Solar geometry

The solar shading rises in the East and sets in the West. The solar shading travels in an arc, reaching its highest altitude in the North (for the Southern hemisphere).

Sydney Sun Path

An important requirement of the design process is to ensure the building is shaded from the solar shading for as many hours as possible throughout the whole day, during the course of the entire year. However a balance must be achieved in order to ensure that the level of natural light entering the building is not unacceptably reduced.

North facing façades

For a predominately North facing façade, a relatviely small amount of shading can be achieved using a fixed horizontal brise soleil.

South Facing Façades

In the mornings and in winter, such a device cannot stop direct rays of the sun from penetrating the building since the solar shading is much lower. However the heat gain and solar glare is greatly reduced in winter and therefore this may not considered to be a major problem.

East or West facing façades

With a predominantly East or West facing façade, a fixed system will not perform well throughout the whole day as the altitude of the solar shading is much lower. Sunlight will pass directly under most horizontal shading systems as shown in the illustration below.

East or West Facing Façades

To overcome this problem, effective solar shading can be achieved using a movable solar shading system.

Controllable fins, unlike fixed, can hang vertically in front of a window and still optimise solar shading and visibility thanks to specially written computer software which ensures that the louvres follow the path of the sun.

Controllable solar shading systems enable the building to react to the changes in the weather and to the solar shading's position so as to optimise the flows of heat and light energy through the façade. This in turn has a positive effect on reducing the heat load and glare, and enhancing the use of natural daylight, thereby reducing the operating costs of the building.

Controllable VSA

Controllable solar shading systems reduce the likelihood of over-shading or under-shading and will result in the optimum shading angle at all times.

Optimum shading angle

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