Abstract
The efficiency of vapor discharge by vertical air layers has been extensively studied in our previous papers when outer board composing air layer excludes completely vapor transmission. It is the purpose of this paper to study the efficiency of vapor discharge by vertical air layers when outer board is made of materials with vapor transmission effect. A quantitative comparison is made between the results obtained in present experiments and those in previous experiments. Furthermore, we propose a computation model of vapor transmission for the prevention design of moisture and condensation in building with vertical air layers. Comparing the computed values with the experimental results, a fairly good correnspondence is observed between these two values. Finally, the values of equivalent permeance resistance are presented for each thickness of air layer in two cases where the heights of air layer are 3 and 6 meters.
