Evaluation of the hygrothermal performance by wall layer component of wooden houses using WUFI simulation program

Thermal performance of wooden houses used by building materials effectively contributing to building energy saving has been improved. However, the performance was decreased to the condensation and mould growth from exterior wall because the moisture control was difficult to high insulation and airtightness. Therefore, the hygrothermal performance of exterior wall, that selected 5 types of wooden houses, evaluated using the hygrothermal simulation program: heat and moisture behavior, condensation and mould growth risk. Wooden houses were selected Rural houses standard plans '10 and '14, 2''x6'' type, EIFS and wood-based passive house. And the wall A, B, C, D and E were determined by layer component of each wall. The U-value of exterior wall are 0.171, 0.172, 0.221, 0.150, 0.079 W/m2K. The OSB absolute water content of the wall A and C was exceeds the reference value of 20%, and it was confirmed that condensation occur at insulation material inner surface through the condensation evaluation in the winter. The wall D and E showed excellent results with condensation and water content evaluation compared to others. However, mould growth risk assessment in all five types of wall had have risk. We were determined that hygrothermal performance difference of exterior wall occur the difference in the layer structure rather than in thermal performance.