Typically, thermographic measurements are used to analyze the building envelope in a qualitative way (e.g. detection of thermal bridges, missing insulation, etc.). Besides, thermography can also be used to obtain surface temperatures, which can give an indication of the thermal performance of the building envelope. In this paper the influence of the most important environmental parameters on the thermographic analysis of different wall types is examined using a multivariable parameter study. This results in guidelines that are in good accordance with the existing guidelines. Furthermore some remarks were made concerning the ambiguities in the existing guidelines. INTRODUCTIONEurope has high ambitions concerning energy efficiency and the reduction of greenhouse gas emissions. By 2050, one of the goals is to reduce the CO2-emissions by more than 80 %, which is impossible with the current policy. In order to reach this goal, the percentage of renovated buildings has to increase from 1% to around 2,5% per year by 2020 [1]. For new buildings, one of the key factors to satisfy the need for energy efficiency is a high performing building envelope, which can be achieved by a high insulation level and an excellent airtightness. In this context, infrared thermography (IR) is a valuable non-destructive tool which can be used both for evaluating the execution quality of the building envelope or for determining where renovation of the building envelope is necessary. For a proper assessment of the wall surface temperature the building envelope has to be as close as possible to steady-state conditions. Therefore an adequate knowledge of the influence of environmental parameters (solar irradiation, wind velocity, sky radiation, etc.) and building parameters (thermal mass of the structure) on the dynamic behavior of the building envelope is needed. Due to the large number of parameters that influence this dynamic behavior together with the limitations of the existing thermographic cameras, additional research is necessary to make quantitative surveys more reliable. In what follows an overview of the currently existing guidelines is given. Starting from the existing guidelines, simulations were conducted to investigate the dynamic behaviour of the wall surface temperature for different combinations of environmental parameters. Finally, feedback on the currently existing standards is given taking into account the results obtained by the simulations.

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