Moisture Buffer Effect and its Impact on Indoor Environment

The moisture buffer effect of building materials may have great influence on indoor hygrothermal environment. In order to characterize the moisture buffering ability of materials, the basic concept of moisture buffer value (MBV) is adopted. Firstly, a theoretical correction factor is introduced in this paper. The moisture uptake/release by hygroscopic materials can be calculated with the factor and the basic MBV. Furthermore, the validation of the correction factor is carried out. The impact of moisture buffering on indoor environment is assessed by using numerical simulations. The results show that the application of hygroscopic materials with large MBV values could reduce the fluctuation of indoor relative humidity, thus decreasing the energy demand for dehumification. The potential energy saving rate of the test building in temperate climates and semi-arid climates could be up to 25-30%. Finally, the relationship between MBV and potential energy saving rate is discussed. (c) 2017 The Authors. Published by Elsevier Ltd.