Combining Infrared Thermography and Numerical Analysis for Evaluating Thermal Bridges In Buildings: A Case Study

摘要

Energy dispersions for transmission in buildings with highly insulated envelope are mainly due to thermal bridges. And because the energy certification of buildings shall be based on real thermal performance and not on theoretical components, nowadays their incidence on energy saving is relevant. Currently, infrared thermography is considered exclusively as a qualitative tool to detect thermal irregularities in buildings, but thermographic inspection allows not only the localization of thermal bridges, but also the identification of temperature field and, therefore, the quantization of the energy losses through such elements of discontinuities. This approach marks a shift from a qualitative to a quantitative analysis of the thermographic image of a building. The aim of this paper is to study the effect of three different types of thermal bridge, estimated as a percentage increase of the homogeneous wall thermal transmittance. Results are obtained exclusively with thermographic surveys without further information on the wall stratigraphy. Finally, the methodology has been validated by comparing with the results obtained by numerical calculation.