lot during roofing work does not pay enough attention to the important details such as vapor barrier or waterproof underlay film.It is believed that directly cover the roof, qualitative performance, provide an ideal condition and appearance of the building both inside and outside.Much attention is paid to the heaters, but underlay film remains as if in the background and is considered insignificant and not very important element.
Such an attitude to the issues of arrangement of the roof is fundamentally not true - the use of under-roof foil several times to increase the life of the roof and provide comfortable living conditions inside the building.
Let's see what will happen with the insulated roof without a vapor barrier
In cold weather, the temperature difference between the street and the room will lead to the formation of steam under the roof, and insulation will be constantly under the influence of steam.Such action would make wet insulation, leading to a significant loss of its physical and
constant accumulation of moisture results in addition to the still very much discomfort and trouble for natural materials - can form a variety of microorganisms, fungi, wood destroying wooden structures.Because it is so important to protect the materials from the harmful effects of steam and remove moisture that collects inside the structure.
most acceptable way out of this situation is recognized as free space between the insulation and roof covering.In other words - there are conditions for airing during which the moisture is removed from the layer of insulation.And to ensure that the air could not stand the heat must be applied to the film wind-proof insulation.Especially needed windscreen if acts of mineral wool insulation, due to the fact that the wind will blow it easy to part of such a heater, characterized by fragility.
As windproof, while thermal protection is easily overlooked wet steam, which does not allow the formation of condensate.And the moisture in any case should not be held inside the structure.The work is not a simple construction ensures that the film for vapor barrier made from several layers.The most common film consisting of three layers.In these middle layer guaranteeing durability, both sides covered with polythene.
reinforcing layer applied to polypropylene polymer or an organic material (for example, moisture resistant board).The elastic properties of paperboard is much smaller than that of the synthetic material, but the strength characteristics mentioned.Usually on the reflective coating is applied to the film, which makes it possible to additionally insulate the room.
I would also like to pay special attention to consumers that underlay when installing a vapor barrier film should be carefully produce sealing seams, sealant or tape designed for such purposes.When installing windproof film such measures are not deemed important enough.