Study of heat protection of translucent external envelope in winter period

Abstract

This article presents the results of thermophysical studies conducted in the cold period by non-destructive testing of translucent exterior building envelopes for heat protection and illumination of the room with natural light. As an object of study was chosen 3-room apartment on the fifth floor of the 17-storey residential complex “Sport Towers”, located in Astana, where the survey was conducted in the daytime. The window openings of the respective rooms were selected as translucent exterior envelope. As a result of the survey it was found that the internal temperature of the living rooms has a deviation of 3.5% from the optimal norm on the parameters of microclimate of the premises, which leads to a violation of the norm and overconsumption of heat energy for heating due to inadequate thermal protection of translucent exterior envelopes. At humidity 48.1% and internal temperature of the room 19.3 °C that the dew point was 8.1 °C. The value of the surface temperature including in the zone of adjoining to opaque elements of the considered structures showed deviation from -16.3°C to 8.0°C, which exceeds the dew point temperature in some cases in 3 times. The total area that does not meet the norm of the examined fragments of translucent exterior envelopes was from 5.9% to 100%. It is noted that the above deviations in heat protection of buildings can lead to the appearance of mold on the inner surface of the envelopes. The qualitative and quantitative indicators obtained as a result of thermophysical studies are the basis for the design of translucent parts of the exterior envelope when they work together with the blind wall part of the façade systems and in the future will be taken into account by designers in the development of new energy-saving exterior envelope structures, which are planned to be implemented throughout the Republic of Kazakhstan, taking into account climatic features.