Comparative analysis of thermal characterisation methodologies of a historical double leaf masonry wall

Abstract

Energy consumption for heating and air conditioning is one of the main factors to consider in the energy efficiency of buildings. Correctly assessing thermal losses in the envelope is essential for decision making when it comes to minimising the cost of using thermal installations and improving the thermal comfort of a building. This paper presents a comparative analysis between different thermal transmittance characterisation methodologies. The comparison is carried out between different quantitative methodologies, including that which is described in the Spanish Technical Building Code CTE DB-HE, direct measurement methodologies through an analysis of materials, and in-situ measurements based on the recording of heat flux and temperature differentials as described in ISO 9869. The results of the application of these methodologies on a traditional Mediterranean wall reveal significant differences between each of them. Further, the discrepancies between the default transmittance values and the values obtained through direct measurement of the envelope are determined.