Thermal insulation materials have the ability to freely pass through the steam at that time of the year, when the window is a plus temperature. But when it falls below zero, problems with vapor permeability immediately begin. So that the walls and insulation in your room are not damaged from the accumulating warm steam, when the heat -insulating material is installed, an additional vapor barrier is added. Usually it consists of the so -called vapor barrier film.
Such vapor barrier is very important for insulation of roofs and basements. It is also used for unsuitable attics. It happens that for vapor barrier, ordinary polyethylene or pergamin is used. But these materials are considered less reliable than a specialized vapor barrier film, because they are destroyed faster. Other varieties of vapor barrier are also used, such as foil thermal insulation. It is used in the construction of saunas or baths, as it has the ability to reflect thermal radiation. In the technology of vapor barrier material, it is important that it necessarily closes the entire surface with a continuous layer. After all, even the smallest holes and gaps will completely violate the protective vapor barrier. It should be remembered that the vapor barrier film is not damaged, it cannot be strongly stretched during installation.