A methodological approach for heat-flow meter data post-processing under different climatic conditions and wall orientations

The European Union has committed itself to reduce significantly greenhouse gas emissions. To achieve this goal, the European Green Deal is focused on energy efficiency and the decarbonization of the building stock. The implementation of energy saving measures in old buildings is one of the most effective strategies, but this needs the comprehension of the actual thermal behavior of the buildings’ envelopes. One of the most important properties of walls is the thermal transmittance, which can be assessed through the Heat-Flow meter (HFM) method. It needs stable environmental conditions which may not always be satisfied. So, the data post-processing becomes fundamental. Here, an experimental investigation was conducted on a recently built structure, equipped with a solar shading device installed on the south façade. The HFM method was applied both on north and south walls. Data were recorded during winter and summer for analyzing the influence of the external environmental conditions. Two methodological approaches were proposed, based on specific criteria for data selection. The aim of this study is therefore the proposal of regulated procedures for heat-flow meters data post-processing. The preliminary results are satisfactory, showing that the proposed methods can be considered reliable.