REALIZATION OF SUNSPACES IN BUILDINGS. EVALUATION OF EFFECTIVE SOLAR ABSORPTIONS

Sunspaces are passive systems which are easy to achieve in building restructuring works and which can give rise to an architectural improvement of the shell, to an extension of the usable spaces, whilst at the same time improving radiation capturing and reducing the energy requirement of the building. In this work is presented a detailed study on the optical behaviour of the sunspace-room system by means of the evaluation of the effective absorption coefficient of the sunspace and the adjacent environment determined by resolving the optical field in the solar band in the sunspace and the adjacent environment. By means of an extended parametrical analysis, the dependence of the absorption coefficient of the sunspace and the environment from the main optical and geometrical variables which characterise the phenomenon of absorption was investigated. The analysis was conducted considering a space communicating by means of a glazed surface of variable dimensions, with a sunspace with different geometries whose transparent surfaces can be placed or oriented differently, as the reference building type. Different absorption coefficient values are considered for the opaque surfaces and two types of glass. The effective values of the absorption coefficient of the sunspace allow for the accurate calculation of solar gains, for a correct evaluation of the improvement in the energy performance of the building.