Determination of vapor permeability coefficients and optimization of experimental methods for typical building materials
The vapor permeability coefficient of building materials indicates the ability of water vapor to penetrate the material under specific environmental conditions,making it an important parameter for assessing the thermal in-sulation and waterproofing performance of walls.However,this coefficient varies with changes in environmental hu-midity,thus it is unreasonable to treat it as a constant in thermal calculations.This study,based on the dry-wet cup method outlined in the international standard ISO 12572,improves the experimental approach to measure the vapor permeability coefficients of four typical building materials,and also analyzes the errors and proposes four sealing op-timization methods,ultimately expressing the vapor permeability coefficient as a single-valued function of moisture content.The results show that the optimized sealing methods can accurately measure the vapor permeability coeffi-cients of these materials and can be applied to various types of building materials.
building materialsvapor permeability coefficientwet and dry cup methodsealing method
NETL
NSTL
万方数据
