Abstract
In this paper, the authors report the values experimented of aqueous vapour permeability of various building materials and walls; concrete walls, concrete block walls, metal lath mortar walls, asphalt roofing vapour barriers, etc. We propose the values of aqueous vapour diffusivities in the "air-layers in the vail" and "surface airlayers of the wall" in several conditions, after theoretically considering them. This paper is the 3rd report of our experimental Studies. The experimental apparatus was described in the 1 st report. (Trans, of Arch. Inst. Jap., No. 57, July, 1957)
