Passive solar protection systems

One of the fundamental aspects for optimising energy efficiency in the new trends of sustainable architecture is solar protection, which prevents overheating inside buildings. By adequately controlling sunlight, energy is reflected and dissipated outside the living space, thus reducing energy demand. In this respect, the STACBOND® aluminium composite panel has a wide range of application possibilities. Below is a selection of passive solutions for sun protection and the use of natural light.


Ventilated facades are an external enclosure system that allows the STACBOND® composite panel to be placed separately from a layer of thermal insulation by means of a supporting structure. Thanks to the effect of sunlight, this separation distance heats the interior air and generates a current between the panel and the facade. This system achieves optimal thermal and acoustic insulation, as well as effective protection against atmospheric agents.

The main advantage of ventilated facades is the energy saving, which is possible thanks to the chamber between the external wall of the building and the composite panel, which causes the thermal transmittance to be reduced and energy saved.


Cantilevers are fixed, horizontal solar protection systems that generate shadows on the facade and openings of a building in summer, but in winter allow the solar radiation to pass through. The cantilevers usually protrude about one metre above the facade, although the size should ideally be calculated according to the orientation of the facade. They are a very effective method to prevent our building from heating up excessively in summer, and can reduce the incidence of solar radiation by around 40%. This system is a good option to take into account in single-family houses where, many times, we have more freedom when modifying the exterior of our house.

As they are fixed and horizontal elements, cantilevers are less effective in those areas of the building where the sun has a lower angle, such as in the west and east, and are more suitable for use in south-facing areas. The use of STACBOND® composite panel in these systems provides many advantages, such as ease of installation, reduced weight of the substructure and material, and a wide variety of finishes.


Vertical or horizontal exterior slat systems are systems that, when properly adjusted and used, are very effective as a barrier against solar radiation. These systems are usually placed vertically and therefore are especially suitable for orientations where solar radiation hits at a lesser angle, that is, the east and west orientation, where horizontal solar protection systems are not so effective since the sun is low and hits the facade and windows.

Their main advantage is that, although they avoid the entry of direct solar radiation, they allow the entry of indirect light, achieving a correct illumination of the interiors. It is essential to use these systems in exteriors since, in the interior, once the radiation passes through a glass, they would only serve to filter the light, but would not prevent the heating of the interior space.

Slat systems do not have to be used only in front of glass openings, they can also be used to cover the entire facade of a building, like a second skin, generating shade on the facade and thus preventing it from overheating. The mechanical behaviour of the STACBOND® composite panel makes this product an ideal solution in slat systems, and allows the finishes to be unified with the rest of the building’s facade.


Among the multiple transformation possibilities of the STACBOND® composite panel, perforation offers a wide variety of aesthetic solutions for filtering light on facades. Perforation allows the use of an infinite number of shapes and sizes that can be combined and regular and non-regular patterns, making it an ideal option for the personalisation of buildings while greatly improving their energy efficiency.