ADJUSTING THE DESIGN THERMAL CONDUCTIVITY CONSIDERED BY THE SPANISH BUILDING TECHNICAL CODE FOR FAÇADE MATERIALS

Abstract

The Spanish Technical Building Code establishes a temperature of 10°C and an equilibrium moisture content with a relative humidity of 50% and 23ºC, respectively, as reference to determine the design thermal values of construction materials. However, these reference values are not consistent with the actual climatic conditions of the country, resulting in optimistic designs of the building thermal envelopes and higher energy consumptions than expected by design. This article analyses these differences, reviews the weaknesses of the Spanish Code in this area, and uses a recently developed procedure to determine the actual thermal conductivity of façade materials with similar precision and less calculation effort that the standard UNE-EN ISO 10456. All this would contribute to improve the thermal design currently defined for the Spanish buildings.