Field thermal imaging surveys of residential buildings – a prerequisite for the development of energy-efficient external enclosures

Abstract

The work involved a full-scale thermal imaging survey of a residential building during a hot period of time, where the effect of solar heating of the building's façade and the inner surface of the outer enclosure was studied, taking into account the orientation of the building and the time of the survey. As a result, it was found that the effect of solar heating on the building’s façade significantly increases the temperature on the façade surface, where, depending on the façade orientation and time, the building’s façade surface is exposed to heating from the east, west and south sides. Thus, the maximum values of the façade surface temperature reach 63.1°C, 57.0°C and 53.4°C, respectively, which is almost twice as high as the initial temperature values. Solar heating also has a significant effect on the temperature of the inner surface of the external enclosure, also depending on the façade orientation. Thus, on the east side in the morning, the surface temperature of the external enclosure increases by 3.8°C, which continues until 16:00. The influence of the sun provokes heating of the inner surface of the external enclosure of the living room on the western side by 4.2°C, and on the southern side the maximum temperature on the surface of the inner enclosure was observed in the period from 12:00 to 16:00, which exceeded the initial one by up to 3.8°C. At that, the influence of heating from the sun on the northern side was not observed. With that, it was found that the influence of solar heating of the building façade provokes deviations in the microclimate of the room, where the deviation in the permissible internal air temperature of the living room is 14.1% during the day, and in the optimal humidity by 13.3% in the afternoon. The findings of this study can be taken into account when designing or developing new energy-efficient external enclosing wall structures, where the criterion of heat resistance must also be taken into account in parallel with the criterion of heat protection in the climatic features of the Republic of Kazakhstan.