Examination of thermal properties and defects of brick walls with infrared thermograpy and hot box methods

In today?s constructions, an emphasis was given to the design of energy efficient structures and improvement of existing structures in terms of their energy efficiency. Most existing structures do not have enough thermal insulation characteristics, causing significant heat loss and damp problems. Such structures should be examined by means of non-destructive methods, allowing fast and efficient diagnostic studies. InfraRed Thermography (IRT) is one the non-destructive methods which can be used for the detection of thermal failures and their causes. This study dealt with the development of standard methods for the quantitative analyses of thermal insulation features and thermal failures by the use of IRT.By the study:--The thermal transmission characteristics of walls built with bricks having improved thermal insulation properties, such as thermal transmittance value (U, W m-2K-1 ), thermal resistance (R, m2K W-1), heat flow density (q, W m-2)?, thermal conductivity (?, W m-1K-1)?, and ?thermal diffusivity (?, m2 s-1), were examined by means of IRT;-For such examinations, an experimental set-up and analytic methods were developed in laboratory by the joint use of calibrated hot box method and quantitative IRT;-The surface temperature characteristics of some thermal defects, such as thermal bridge, air leakage, and surface condensation problems were determined in terms of ?temperature index (TI, unitless)? and ?rate of warming up (RW, °C s-1/2)?.Thermal monitoring of the wall surfaces at the cold side during the heating period allowed establishing the graphs showing the surface temperature evolution as a function of time. The data were analysed to determine the RW and TI values distinctive for each thermal defect observed on the brick wall samples. Thermal monitoring of the wall surfaces during the steady state conditions also allowed determining the thermal transmittance characteristics of the brick wall samples.The standard data obtained by the laboratory analyses, in fact, established the control data for the in-situ analyses. This meant that the efficiency of thermal insulation characteristics for the existing buildings and the detection of thermal failures can be examined on site on quantitative base by the use of IRT