摘要 |
The present invention relates to a variable-humidity directional vapour barrier which comprises at least two layers, wherein one layer (layer 1) is humidity-variable and the other layer (layer 2) is humidity-independent. For layer 1, the quotient for the water vapour diffusion resistance from the sd value at 25% mean relative air humidity to the sd value at 71.5% mean relative air humidity is greater than 3. For layer 2, the quotient for the water vapour diffusion resistance from the sd value at 25% mean relative air humidity to the sd value at 71.5% mean relative air humidity is less than 1.5. Furthermore, the invention relates to the use of the vapour barrier for sealing buildings and to a system which comprises said vapour barrier. Furthermore, the invention relates to the use of a certain film for sealing a space in buildings which is closed by an exterior skin, wherein the film comprises defined film sides X and Y or layers 1 and 2 and is arranged in a certain way. |