Assessing the impact of moisture buffering properties of materials on indoor environmental quality: A study on a recycled material plaster

This study examines Moisture Buffer Value ( ) of interior finishing layers, which impacts buildings internal relative humidity, thus indoor environmental quality. The depends on material's moisture capacity and vapor diffusion resistance factor, both of which depends on relative humidity. The paper aims to (i) characterize a new recycled material plaster that includes construction and food industry waste through laboratory measurements, (ii) use dynamical building simulations to quantify the impact of the of existing and the new interior plaster on relative humidity in real design scenarios, and (iii) evaluate how changing the definition of the to consider its dependence on indoor air relative humidity can improve its accuracy. Results show that the plaster's moisture buffering properties significantly reduce the variations of the relative humidity of interior climates compared to a vapor-tight finishing layer. The performances of the new plaster made with recycled materials are comparable to those of the other plasters. The new definitions (“Dynamical and “Summer/Winter ”) show a significantly improved correlation with the relative humidity variations of indoor climates of buildings, observed in dynamic simulations, with respect to the typically used practical . The new definitions are therefore promising for practical applications. • A new MBV definition that accounts for relative humidity dependence is introduced • A robust correlation between MBV and building interior climate is demonstrated • The hygrothermal performances of a novel recycled-material plaster are analysed • Recycled components do not adversely affect moisture buffering properties