标准摘要
ISO 21129:2007 specifies a box method for determining the water-vapour permeability of building materials. The box method is used primarily to measure the water-vapour permeance of materials that have low water-vapour resistance, in which the influence of the surface-humidity transmission-resistance cannot be ignored.
英文名称Hygrothermal performance of building materials and products — Determination of water-vapour transmission properties — Box method