Experimental Evidence on the Thermal Performance of Opaque Surfaces in Mediterranean Climate

Abstract

The thermal insulation of buildings, intended as wrap feature which determines the dispersion of heat, the reference parameter is necessary to contain the thermal losses during the winter season. The transmittance of the opaque components, used as an indicator of the energy quality of a casing, together with the overall coefficient of dispersion, represents a proper descriptor of the behavior during the heating season. However, if a strong insulation in winter conditions brings only positive effects, the same cannot be said for the summer conditions. A high value of the insulation in the casing is convenient only when the gains free, either in the form of solar contribution that of endogenous heat, are controlled and restricted. From the national transposition of the 2002/91/CE legislation up to the 2010/31/EU on the energy performance of buildings, performance values are set very restrictive transmittance of opaque surfaces that both of those transparent to the new buildings. The same does not happen for the thermophysical characteristics able to implement strategies for the control of solar radiation during the summer period, the fluctuations in external temperatures during the summer period. This article shows some experimental evidence of the effects on transmission rate and density of the opaque elements of the buildings carried out on a case study of a representative building of climate-Mediterranean summer: The study verify the results produced by increased insulation of the building envelope on energy performance of buildings during the summer through indicators such as temperature and energy consumption to maintain the same constant with respect to the prescribed values.