该标准规定了用于计算通过建筑结构的热和湿气的非稳定转移的模拟方法中使用的方程式。 它还提供了一个基准示例，旨在用于验证声称符合本标准的模拟方法以及允许的公差。 本标准中的等式考虑了以下存储和一维传输现象: - 干燥建筑材料和吸收水中的储热; - 依赖于热传导的热传导; - 通过蒸气扩散潜热传递; - 通过蒸汽吸附和毛细管力储存水分; - 通过蒸气扩散进行水分输送; - 通过液体输送（表面扩散和毛细管流动）的湿气输送。 本标准中描述的等式描述了以下气候变量: - 内部和外部温度; - 内部和外部湿度; - 太阳能和长波辐射; - 降水（正常和下雨）; - 风速和方向。 本标准中描述的湿热方程不适用于以下情况: - 通过孔和裂缝进行对流; - 二维效应起着重要的作用（例如，上升潮湿，热桥条件等等

This standard specifies the equations to be used in a simulation method for calculating the non steady transfer of heat and moisture through building structures. It also provides a benchmark example intended to be used for validating a simulation method claiming conformity with this standard, together with the allowed tolerances. The equations in this standard take account of the following storage and one-dimensional transport phenomena: - heat storage in dry building materials and absorbed water; - heat transport by moisture-dependent thermal conduction; - latent heat transfer by vapour diffusion; - moisture storage by vapour sorption and capillary forces; - moisture transport by vapour diffusion; - moisture transport by liquid transport (surface diffusion and capillary flow). The equations described in this standard account for the following climatic variables: - internal and external temperature; - internal and external humidity; - solar and longwave radiation; - precipitation (normal and driving rain); - wind speed and direction. The hygrothermal equations described in this standard shall not be applied in cases where: - convection takes place through holes and cracks; - two-dimensional effects play an important part (e.g. rising damp, conditions around thermal bridges, effect of gravitational forces); • hydraulic, osmotic, electrophoretic forces are present; daily mean temperatures in the component exceed 50 °C.