ANALYSIS OF SIMPLIFIED CALCULATION PROCEDURES OF SOLAR GAIN IN BUILDINGS

A critical analysis of the calculation procedure of solar gain in buildings with reference to an attached sunspace bordering air conditioned environments was developed. The EN ISO 13790:2008 Standard provides a simplified calculation method for the estimation of solar gain based upon the monthly energy balance in a stationary regime, to be applied both during winter heating and summer cooling. Moreover, the Standard hypothesises possible simplifications to be evaluated in relation to climatic conditions and the type of greenhouse-environment system. The direct, indirect and total solar contribution evaluated by means of the Standard are compared with those obtained with a dynamic calculation code, with the aim of highlighting the limits of the schematization adopted by the Standard. Furthermore, the gain in an airconditioned environment obtained by means of a windowed wall is compared with that produced by the use of a sunspace opposite the same wall.