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Buildings use a large amount of energy, depending on the climate. To design buildings with high energy and thermal performance in the future, it is necessary to use weather data that reflect future climatic information. Some future weather files for building simulations have been developed. However, these datasets are based on different predictions, and each future weather file has a different creation process. Such methodological differences may lead to differences in predicting the energy and thermal performance of buildings. Understanding the characteristics of each data type is necessary for its appropriate use. However, limited information is available for properly utilizing future weather data for building simulations. This study aims to provide information on the characteristics of future weather data for better utilization. After thoroughly reviewing the existing data and creation methods, we propose a framework for understanding future weather data based on their creative process. We collected five types of future weather datasets available in Japan and compared their characteristics. One of these datasets is the future weather dataset based on climate information provided by the National Institute for Environmental Studies (NIES). We confirmed the degree of variation in each weather element and predicted cooling/heating demand using future weather data available in Japan.

Biophilic design is aimed at creating a good habitat for people by enhancing the connectedness between people and nature in the urban environment; its effects on promoting psychological health are well known, but further studies are required to quantify the effects on physical and physiological aspects to provide a holistic view to support design practice. In this study, we focused on the physical aspect and quantitatively analyzed the effects of biophilic design on the thermal environment and occupants' thermal sensations. Field measurements and questionnaire surveys were conducted at a multifloor indoor garden in a public building in Kumamoto, Japan, with an artificial waterfall, pond, plants, and natural light as biophilic elements. Predicted mean vote was calculated using field measurement results as an objective indicator to assess thermal comfort. Questionnaires were used to verify the psychological effects and clarify the occupants' thermal sensations by comparing with field measurement results. The effects of the waterfall were studied when it was switched on and off. The results suggest the rationality behind incorporating biophilic design inside buildings, in terms of the physical aspect, highlighting the psychological effectiveness, especially during winter, and the benefits of thermal comfort, especially during summer.

Louvre openings are widely used for ventilation in residences at tropical regions. Traditional households rely primarily on natural ventilation for cooling instead of using air conditioners throughout the year. Hence, a design strategy that maximizes the natural ventilation rate with an accurate discharge coefficient is necessary. The discharge coefficient for a traditional window without a louvre is 0.6. However, studies on discharge coefficients for louvre openings with sashes are lacking. Discharge coefficient will differ according to the installed sash owing to increased contraction and friction losses. Therefore, we determined the discharge coefficient value for various sash angles and the impact of the louvre geometric parameter on the discharge coefficient. To investigate the effects of geometry on the discharge coefficient, real-time natural ventilation rate was quantified using the tracer gas (constant concentration) method. Pressure difference, outdoor wind velocity, and temperature difference were also measured. The opening types were divided into three cases: louvres with a sash angle of 0°, 15°, and 30° with similar opening areas. The results show that discharge coefficients for louvres with sash angles of 0°, 15°, and 30° are 0.80, 0.62, and 0.41, respectively, indicating that the coefficient decreases with increasing sash opening angle.

With the aim of establishing a zero-energy housing (ZEH), an intelligent envelope system composed of a passive dehumidification and solar collection system (PDSC system) based on thermodynamic energy theory and an energy recovery ventilation (ERV) unit has been developed, abbreviated as PSE (PDSC & ERV) system, which can be expected to control the indoor hygrothermal environment by using renewable energy further to reduce the heating and cooling demand for the HVAC system. In this study, the measurement experiments were conducted in a wooden house equipped with a PSE system, and the temperature and humidity distributions in the rooms were assessed using thermohygrometer sensors. The field comparison experiments for the three systems (exhaust-only ventilation system, ERV system, and PSE system) were performed separately under various meteorological conditions in summer and winter. The measurement results in summer showed that the PSE system has a significant dehumidification effect compared to the exhaust-only and ERV-only ventilation systems and could effectively reduce the latent heat load caused by ventilation. The measurement results in winter indicated that the PSE system has the effect of heat collection and humidity control as well as reducing the sensible heat load originating from ventilation.

Windows are among building components that have the strongest effect on thermal load. They play a significant role in heat loss in buildings because they usually have a largely higher thermal conductance than other components of the building envelope. Although many studies have highlighted the relevance of heat transfer through frames and aimed to improve their thermal performance, poorly insulated aluminum frames (thermal conductivity of aluminum is 160 W/m·K, while that of polyvinyl chloride [PVC] is 0.17 W/m·K) are still in use in Japan. Therefore, the U-values of different window frames were calculated, and annual thermal loads were calculated according to the window configurations, including the frame, glazing, and cavity. We focused on standard residential buildings in Japan with a total floor area of 120.6 m2 (two-story building), and the number of newly built houses and the application rate of window configurations in 2019 were surveyed to estimate the CO2 emissions by regions. CO2 emissions were reduced by approximately 3.98–6.58% with the application of PVC frames. Furthermore, CO2 emissions were converted into the amount of CO2 gas absorbed by cedar trees, which cover nearly 18% of the total land area of Japan. In conclusion, analogous to the amount of CO2 gas absorbed by cedar trees, the absorption effect was equivalent to 327,743–564,416 cedar trees. Changing the window frame material can facilitate a significant energy-saving effect as a considerable amount of energy is saved, especially at a city scale. [ABSTRACT FROM AUTHOR]