| 摘要 |
<p>The present invention relates to a water vapour barrier (15) that comprises a first, water impervious membrane (19) having a plurality of first through openings (21) defined therein, and a second, water impervious membrane (22) which is arranged opposite to the first membrane (19). A water absorbing material (18) is arranged within one or more spaces defined between the first and second membranes (19, 22), and the water vapour barrier (15) is characterised in that at least part of the second membrane (22) is of a material of the type having a water vapour diffusion resistance, which varies in dependency of the relative humidity of air in contact therewith, such that the vapour diffusion resistance is reduced when the relative humidity increases, and vice versa. The invention further relates to a method of making the water vapour barrier.</p> |
