This study first reviewed previous studies on floor heating systems based on the installation of a phase change material (PCM) and the current status of technical developments and found that PCM-based research is still in its infancy. In particular, the improvement of floor heat storage performance in indoor environments by combining a PCM with existing floor structures has not been subject to previous research. Thus, a PCM-based radiant floor heating system that utilizes hot water as a heat source and can be used in conjunction with the widespread wet construction method can be considered novel. This study found the most suitable PCM melting temperature for the proposed PCM-based radiant floor heating system ranged from approximately 35 °C to 45 °C for a floor thickness of 70 mm and a PCM thickness of 10 mm. Mock-up test results, which aimed to assess the performance of the radiant floor heating system with and without the PCM, revealed that the PCM-based room was able to maintain a temperature that was 0.2 °C higher than that of the room without the PCM. This was due to the rise in temperature caused by the PCM’s heat storage capacity and the emission of waste heat that was otherwise lost to the underside of the hot water pipe when the PCM was not present.

We assessed the usefulness of phase-change material (PCM)-based thermal plates fabricated from wood-plastic composites (WPCs) in mitigating the urban heat island effect. The thermal performance of plates containing PCMs with two different melting temperatures and with two different albedo levels was evaluated. The results showed that the PCM with a melting temperature of 44 °C maintained lower surface and inner temperatures than the PCM with a melting temperature of 25 °C. Moreover, a higher surface albedo resulted in a lower surface temperature. However, the thermal performance of PCMs with different melting temperatures but the same surface albedo did not differ. Using PCM-based materials in roof finishing materials can reduce surface temperatures and improve thermal comfort.

Windcatcher louvers are designed to capture air flowing outside a building in order to increase its natural ventilation. There are no studies that have designed the shape of the louver to increase the natural ventilation efficiency of the building. This study aimed to conduct a computational fluid dynamics simulation and mock-up test of a Clark Y airfoil-type windcatcher louver designed to increase the natural ventilation in a building. The following test results were obtained. The optimal angle of attack of the airfoil was calculated via a numerical analysis, which demonstrated that the wind speed was at its highest when the angle of attack was 8°; further, flow separation occurred at angles exceeding 8°, at which point the wind speed began to decrease. The results of the mock-up test demonstrated that the time required to reduce the concentration of fine particles in the indoor air was 120 s shorter when the windcatcher was installed than when it was not, which indicating that the time to reduce particles represents a 37.5%reduction. These results can be seen as reducing the energy consumption of ventilation in the building because the natural ventilation efficiency is increased.

General cool roof is effective for reduction of cooling load, but it has a problem of increasing heating load. Therefore, the purpose of this study is to complement the disadvantages of the cool roof system by utilizing phase change characteristics of phase change material (PCM). The study was carried out to verify the thermal performance of the PCM cool roof system by measuring the temperature on the top and bottom of the PCM cool roof system by making a miniature model (600 × 600 × 600 mm). PCM was inserted and not inserted, and the temperature difference according to the finish color (brown and white) was compared. As a result, the plate surface temperature using PCM was lower than that without PCM, and time‐lag of temperature increase occurred. As a result of the comparison of temperature according to the finish color (brown and white), white showed a low temperature distribution up to 16.35°C. Even at room temperature, white maintained a low temperature distribution of 5.40°C than brown. The use of PCM cool roof system in roof finishes could lower the surface temperature and keep the room temperature low.

Apartment buildings in Korea have adopted underfloor heating systems using web construction methods based on concrete and hot water systems. However, since such systems consume significant amounts of energy for heating owing to their low thermal storage performance, it is necessary to develop a new system that can minimize energy consumption by improving concrete thermal storage performance. This study proposes a phase-change material (PCM) underfloor heating system to reduce energy consumption in apartment buildings. An optimal design for a PCM underfloor heating system is proposed, and thermal storage performance of the proposed system is evaluated experimentally. The temperature range of the PCM for underfloor heating is also calculated considering the proposed design and comfortable heating conditions for domestic apartment buildings. Results indicate that a PCM underfloor heating system can be constructed in the following order: (1) a 210 mm concrete slab, (2) a 20 mm cushioning material, (3) 40 mm of mortar including a 10 mm PCM thermal storage container, and (4) 40 mm of finishing mortar including wire mesh and hot water pipes. The temperature range of the PCM used for underfloor heating in domestic apartment buildings is 32–45°C. Experimental tests reveal that thermal storage performance of underfloor heating systems that apply 35, 37, 41, and 44°C as representative PCM temperatures is superior to existing systems.