Infrared thermography application for in-situ determination of the building envelope thermal performance

Abstract

During the phase of creating energy audit documentation, many calculations are needed when evaluating the thermal performance of building envelope components due to a large number of distinct components and junctions. Several computer programs are available to assess buildings’ energy consumption, using the thermal performance of building envelope elements as input data. These thermal performances are often provided with varying degrees of accuracy, typically only for the current field of the component, without considering the impact of thermal bridges. However, when using linear heat transfer coefficients ψ, the details provided in thermal bridges’ atlases do not cover all the case studies encountered in the current design, which often requires approximate details. In some cases, the technical documentation of the building is unavailable, which leads to various assumptions about the detailing of the building envelope and a non-realistic picture of the energy performance of the assessed building. The paper presents a methodology and accompanying software called THERMOG that evaluates the thermal performance of the building envelope under actual operating conditions using aerial and terrestrial thermography methods. The paper presents initial findings from some case studies used to calibrate the developed methodology.