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Abstract: In the last years many studies concerning the evaluation of the thermal conductance of building elements via measurements have been carried out; this value has to be ensued from the analysis of recorded temperature and heat flux profiles. The determination of this property in situ would allow a more accurate a more accurate evaluation of the real heating energy demand of a building. Papers discussing different data analysis methods are present in literature and measurements on test components under real conditions and evaluations on different theoretical aspects by means of numerical simulations have been already developed. This paper aims at widening the existent literature of the in situ evaluation of the thermal conductance, through the discussion of the results of a measuring campaign which lasted four years on real buildings, and by comparing the reference specific thermal conductance (C) values with those computed on the basis of the measurements. Various tests on the same elements are discussed. Finally an analysis on the influence of the C value on the evaluation of the net heating energy demand of a building in different climates is presented. [Copyright &y& Elsevier]

Abstract: In this paper an emissivity measurement method is proposed; it relies on individual calibration functions, and is based on the spectral response of a specific IR sensor. The reflected temperature is kept constant during the test, and its knowledge is not required. Results of measurements on materials commonly used as emissivity references in quantitative thermography are reported. Computer simulations of indoor and outdoor thermographic inspections show the differentiated influence of emissivity and surroundings temperature on the measurement accuracy. Finally experimental results of absolute and differential temperature measurements are discussed. [Copyright &y& Elsevier]

Abstract: In the last years many studies have been carried out on the possible improvements of the in situ thermal conductance measurement; as well known, this has to be derived by recorded values of temperatures and heat fluxes. A big effort has been addressed in the implementation and comparison of different analysis methods. The aim of this paper is to widen the existent literature in the study of the influence of different kinds of input data on the final result. First the problem of analysing input data with significant drift in temperature is considered, adopting both nominal clean and noise affected data. Then the effect due to the presence of the Heat Flux Meter (HFM) on the thermal field of the testing element has been analysed, as well as the possibility of recording HFM surface temperature. These studies are based on Finite Element Method (FEM) simulations; both nominal clean and noise affected data have been considered as input. Finally, a difference in emissivity between the heat flux meter and internal plaster surface has been analysed by means of FEM simulations based on nominal clean data. An overall estimation of the occurred deviations in the different cases is shown. [Copyright &y& Elsevier]