Vapor diffusion behavior

The vapor diffusion behavior is described by the Permeability resistance of a homogenous layer of built elements equals with Rv=d·μd·M [m/s], M=54·10(power 8). The vapor permeability resistance of an element composed of multiple layers is R=Σ(dj·μdj)·M. The Partial Pressure of the vapors is pvj=pi-(pi-pe)·ΣRvj/Rv [Pa]. The vapor diffusion behavior is, after all, ideally, without any condensation in the whole width of the built elements. It must be without any superficial condensation on the surface of the elements that close the building.