The innovation of phase change material (PCM) for thermal heat storage is one sustainable passive strategy that can be integrated into building designs. This research was conducted to study and evaluate the performance of the existing materials integrated with PCM and to propose a design strategy that would improve the system. This research suggested copper foam as a medium to be integrated with microencapsulated PCM. Applications of these combined materials will benefit the industry by improving indoor environments and by delivering sufficient thermal comfort for residents as in the case study of the existing 1.6 million terrace houses in Malaysia.

To understand fungal contamination in the indoor environment of the disaster region, a field survey was performed to measure the number of fungal counts and identify isolates in the indoor air of prefabricated temporary housing, privately independent-housing, and rented apartments flooded by the East Japan Great Earthquake disaster tsunami. As a result, the period with the highest detected fungal count was from the rainy season to summer in independent-housing and rented apartments. Moreover, in the temporary housing, the fungal number increased further in winter as indicated by the maximum fungal-number throughout the measurement period. The detection frequency of Aspergillus species was relatively higher in the indoor air of temporary housing than in typical housing in the non-disaster area. Since Aspergillus is known as an allergenic genus, it requires careful attention to the health risk for residents. The extremely high level of fungal condensation in indoor air possibly occurred due to high relative humidity and loss of heat insulation in the building attics. It is suggested that this problem commonly happened in the cold region including the entire disaster region of the East Japan Great Earthquake.

Understanding the thermal performance of the residential envelope is important for optimizing the indoor thermal environment. In this study, the indoor thermal environment and thermal performance of rural residences housing the elderly was determined through field measurements in Qiqihar in 2017 and 2019. The results revealed that the living room temperatures in more than 50% of homes were below the thermal neutral temperature for the elderly (17.32 °C). Moreover, the indoor thermal environment changed significantly during the day, with the predicted mean vote during the day fluctuating from 2 to 4 units. The air change rate of living rooms in 2017 and 2019 was 0.20–2.20 h⁻¹ and 0.15–1.74 h⁻¹, respectively. Residential ventilation times detected by an air-tightness detector ranged from 0.40–1.49 h⁻¹. Furthermore, infrared thermography (IRT) detected air leakage in the windows of the all houses in this study, as well as thermal bridges and condensation on the exterior walls of several houses. The heat transfer coefficient of the exterior walls of all houses detected by IRT was 0.25–0.74 W/(m²·K), and a significant positive correlation was observed between the heat transfer coefficient of the south wall and the window-to-wall ratio. Finally, the heat transfer coefficient of the external walls exhibited a negative but not significant correlation with indoor temperature. This study provides detailed data and guidance for improving the indoor environment of rural houses in severe cold regions.

In this study, questionnaire surveys and field measurements were conducted at houses with elderly people in urban and rural areas across six regions of China. The prevalence of hypertension was approximately 40% in both urban and rural areas. The logistic analysis results indicated a greater prevalence of hypertension in the elderly of rural residences and a low indoor temperature-induced hypertension. According to the field measurement survey, the room temperature was stable at around 23 °C in the housing in northern urban areas equipped with district heating systems, and fluctuated from being equivalent to outdoor temperature to around 15 °C in the southern regions where air-conditioners were used. For housing in the northern rural areas where Chinese Kangs were used, the daily fluctuation in room temperature was significant, and room temperature was stable at a low level in the southern part without space heating. The room temperature and blood pressure were negatively correlated. Therefore, to maintain the health of the elderly in houses with low room temperatures in winter, it is necessary to improve the thermal environment by enhancing the thermal performance of the building and the heating equipment.