The construction industry has made considerable energy-saving efforts in buildings, and studies of energy-savings are ongoing. Shading is used to control the solar radiation transferred through windows. Many studies have examined the position and type of shading in different countries, but few have investigated the effects of shading installation in Korea. In this study, the case of the shading installation according to the standard of Korea, and variations of the heating and cooling load in the unit area on the performance of the windows were examined. This study compared the variations of the heating and cooling load in the case of horizontal shading and the changing position of venetian blinds. This study confirmed that horizontal shading longer than the standard length in Korea saved a maximum of 13% energy consumption. This study confirmed the point of change of energy consumption by the Solar Heat Gain Coefficient (SHGC) variations. The exterior venetian blinds and those between glazing were unaffected by the SHGC. On the other hand, in the case of a south façade, the interior venetian blinds resulted in 24% higher energy consumption than the installation of horizontal shading in case of Window to Wall Ratio (WWR): 80%, U-value: 2.1 and SHGC: 0.4.

Window performance in buildings is very important for energy saving. Many efforts have been made towards saving energy in buildings, and research has focused attention on enhancing the thermal performance of windows. Vacuum glazing has attracted much interest as a means of enhancing the thermal performance of windows by strengthening insulation performance. However, the performance of vacuum glazing differs based on various component combinations, therefore, further study on vacuum glazing is needed. In this paper, through simulations, the authors confirmed the heat transfer value (U-value) of the vacuum glazing composed of various combinations (glass type, number of layers, interval of pillar, etc.). A physical test of vacuum glazing was also performed using standard test methods of windows and the U-value of the vacuum glazing by various intervals of the pillar position was confirmed. The simulation revealed a U-value for vacuum glazing of 0.682–1.466 W/m²·K as per the interval of the pillar position, the performance of solar heat gain, and visible light transmission. The U-value of the double vacuum glazing was calculated as 0.607–1.154 W/m²·K and was similar regardless of the interval of pillar position, the performance of solar heat gain, and visible light transmission. Based on the results of the energy simulation, in the case of a used low U-value of vacuum glazing, the heating and cooling energy consumption in buildings decreased by 2.46%, than when low-e glass and argon gas filled layers were used in windows. Furthermore, in double vacuum glazing, the heating and cooling energy consumption in buildings decreased by 3.91%.

Neural network models are data-driven and are effective for predicting and interpreting nonlinear or unexplainable physical phenomena. This study collected building information and heating energy consumption data from 16,158 old houses, selected key input variables that affect the heating energy consumption based on the collected datasets, and developed a deep neural network (DNN) model that showed the highest accuracy for the prediction of heating energy consumption in an old house. As a result, 11 key input variables were selected, and an optimal DNN model was developed. This optimal DNN model showed the highest prediction accuracy (R² = 0.961) when the number of hidden layers was five and the number of neurons was 22. When the optimal DNN model was applied for the standard model of low-income detached houses, the prediction accuracy (Cv(RMSE)) of the optimal DNN model, compared to the EnergyPlus calculation result, was 8.74%, which satisfied the ASHRAE standard sufficiently.

The interest in zero energy buildings is increasing in South Korea. Zero energy buildings need to save energy by using passive technology. The window performance is important to the thermal insulation of the building. Also, the government regulates the window performance through regulation and standards. However, it is difficult to predict window performance because the components of the window have become complicated due to the various materials used in the glass and frame. Based on window performance standards and regulations, the quality of window performance was managed. In this research, to consider thermal performance in proper window design in South Korea, we confirmed the impact on the thermal performance of the window through various kinds of materials and shapes. The authors also propose a window shape classification and frame calculation method based on actual test results. The authors analyzed the thermal performance data of the windows provided by the Korea Energy Agency and confirmed the change in the thermal performance of the windows by year and by frame material. The average U-value of the window decreased from 2012 to 2015 and maintained similar values until 2017. In 2018, this value was decreased to comply. Also, the authors confirmed the U-value of the windows through actual physical experiments and confirmed the change in thermal performance by the construction of the windows based on the results. The results show, in the case of aluminum windows, the U-value corresponding to Grade 3 (1.4–2.1 W/m²·K) was as high as about 60%. Regarding the analyzed results of the U-values of PVC windows, Grade 3 (U-value of 1.4–2.1 W/m²·K) accounted for about 35%, and Grade 2 (U-value of 1.0–1.4 W/m²·K) for about 29%. This paper also confirmed that the frame U-value of the PVC windows is lower than the frame U-value of the aluminum windows. Therefore, the authors proposed the performance index of the glazing part in PVC and aluminum window design. The results of this research can be used as basic data to identify problems in the method of determining the performance of windows in Korea.

This study evaluated the indoor air quality in 36 new apartment houses in six big cities in Korea from July 2005 to January 2006. Most of the indoor finishing materials in the new houses were environment-friendly and designated by the Korea Air Cleaning & Researching Association. In the new apartments, which were all built with the same finishing materials, air levels of toluene averaged 1475 μg · m^-3 in summer, when there were relatively high temperatures and humidity, and averaged 2711 μg· m^-3 in winter. In addition, benzene, ethylbenzene, styrene, xylene, and formaldehyde measured 9.99, 628, 232, 2392 and 951μg·m^-3 in summer and 9.99, 628, 232, 2392, and 951μg·m^-3 in winter, respectively. Concentrations of volatile organic compounds (VOCs) and formaldehyde were increased as indoor temperature and humidity increased. This study evaluated concentrations of VOCs compounds in a room according to season using enthalpy, which considers two indexes, temperature and humidity. Concentrations of benzene, ethylbenzene, styrene, xylene, and formaldehyde increased with increased enthalpy.