| 摘要 |
<p>A vapour barrier comprises two vapour-tight layers (1, 2) and a water absorbing layer (3) interposed therebetween. Openings (5, 6) are provided in both vapour-tight layers (1, 2). The openings in one layer (1) are arranged in displaced positions relatively to the openings (6) in the other layer (2). The vapour barrier offers a high resistance to the diffusion of water vapour through the vapour barrier from one side towards the other, and enables condensed water formed on the other side of the vapour barrier to travel in the opposite direction and to be evaporated from the first mentioned side.</p> |
