Enhancing indoor comfort and building energy efficiency with cross-laminated timber (CLT) in hygrothermal environments

Abstract

The hygrothermal behavior of a building is important because it directly influences indoor comfort levels and energy consumption. Hence, effective strategies must be implemented to minimize energy consumption while optimizing indoor conditions. This study analyzed indoor hygrothermal environments and energy consumption in scenarios related to passive and active building elements, such as exterior walls and indoor control temperature. A simulation considering hygrothermal behavior in walls and spaces was utilized, and the accuracy of the model was validated via an on-site test. Here, cross-laminated timber (CLT) walls, which have been proposed for their energy-saving potential, were substituted for conventional concrete walls. The application of CLT walls enhances indoor comfort better than concrete walls. Despite using the same CLT material, different wall layer compositions lead to internal moisture accumulation. Hence, it was determined that appropriate wall layer compositions should be selected based on regional climate conditions. Furthermore, although indoor comfort was ensured by varying indoor control temperatures, the energy consumption of the heating and cooling systems increased by up to 81 %. Despite the application of passive elements, an indoor heating temperature of 24 °C achieves an optimal balance between comfort and energy consumption. This temperature ensured a satisfactory indoor comfort level and facilitated a manageable increase in energy consumption. In summary, this study provides nuanced insights into the hygrothermal dynamics of buildings, emphasizing the demand for strategic materials, considering regional climates, and carefully managing indoor temperatures to strike an effective balance between comfort and energy efficiency.