Hygrothermal performance improvement of the Korean wood frame walls using macro-packed phase change materials (MPPCM)

The application of phase change materials (PCM) in various fields is difficult due to their phase instability. To solve these problems, PCM requires shape stabilization. The macro-packed PCM (MPPCM) was suggested and prepared as a method to increase the content of the PCM. In Korea, hot and humid weather conditions in summer, exacerbated by indoor activities, are the major factors of moisture problems. Therefore, the hygrothermal behavior of building materials must be carefully considered to reduce the risk of condensation, reduce the mold growth potential, and enhance the comfort of the indoor environment. In this study, a macro-packed PCM (MPPCM) containing n-octadecane was prepared. The thermal properties of the MPPCM were characterized using a TCi thermal conductivity analyzer and a differential scanning calorimeter (DSC). Also, the hygrothermal performance of building components was evaluated using the WUFI (Wäme und Feuchte instationär) program; these components were wood-frame structures applied the MPPCM. As a result, the phase transitions of n-octadecane occurred at 29.76 °C during heating, and their latent heats were 256.5 J/g. The thermal conductivity of the MPPCM was three times higher than that of the pure PCM. The hygrothermal performance of the wood-frame structures applied the MPPCM, which replaced the use of the vapor retarder, is improved. Also, it is possible to solve the problems of mold growth risk using the prepared MPPCM.