Water vapor barrier film: characteristics, reviews, application

The function of insulating material in construction is far from being the last. Despite the improvement of the characteristics of the finishing materials, only reliable and durable insulators can keep the house from heat losses and harmful effects of moisture. At the same time, traditional heat insulators gradually lose relevance against the background of increasing requirements to the operational qualities of buildings. Their place is occupied by a water vapor barrier film, which also contains thermal protection in its base, but does not allow its overmoistening. In essence, this is a multifunctional protective barrier, by means of which it is possible to protect the structure from cold and moisture.

What is a hydro vapor barrier?

The concept of hydro-vapor insulation is complicated by the functions of the material, which can bear such a name. In the conventional view, this is the membrane that is used to provide protection for the thermal insulator. The most important thing is the phenomena and effects from which it protects. Depending on the field of application, this can be steam, moisture, cold, wind, etc. The composition of the water vapor barrier film also differs - in this plan, it is possible to distinguish profiled and flat membranes. The first are made of polyethylene in the form of sheets with round or square protrusions resembling thorns. Flat membranes are produced not only from polyethylene. In production, polyolefin and even polyvinyl chloride are also used. As a result, a film is obtained, the thickness of which does not exceed 2 mm. Usually the arrangement of roofs and finishing materials uses a flat film with a thickness of less than 1 mm, and thicker membranes are used to protect the foundation.

Characteristics of water vapor insulation

Technical data on the properties of the vapor barrier differ depending on the specific material. For example, it is worth considering the characteristics of the isoprene vapor barrier film. This is one of the most popular materials on the Russian market in this segment:

• Material of construction: 100% polypropylene.
• Tensile load transverse / longitudinal, N / 5 cm: 107/130.
• Water vapor permeability, δ: not less than 7.
• UV stability: 3-4 months.
• Water resistance: the water column is not less than 1000 mm.
• The temperature range in which the material can be used is from -60 to +80 ºC.

Application of the material in roof insulation

Usually in the construction of roofing pies , the water vapor barrier acts as a direct barrier against moisture, and also provides wind protection. This is just the case when high demands are placed on insulators for strength and durability. As a rule, the waterproofing film for the roof is laid on the insulation without venting gap. Such a decision is caused by economic expediency in the form of lower costs for the device of the lathing between a separate heat insulator and a membrane. Windproof films with the effects of steam and waterproofing can be used as underlaying layers in the construction of roofs with different slopes, as the fixation is provided over the rafters over the insulation. The resulting coating acts as a heat-insulating element for the supporting structure, protecting it from penetration of under-roof condensate, as well as from wind, rain and snow.

Application in insulation of frame walls

Installation of the main walls of the house also assumes the provision of steam and waterproofing. In this case, the film protects the material from atmospheric moisture, gusts of wind and powder. But there is, as evidenced by the reviews of masters, another important function that a waterproofing film for roof and frame walls should have is the ability to remove vapors from fibrous insulation material.

The film is installed under the outer skin of the house from the outside of the heat insulator. It is desirable to mount it throughout the frame over the heater in a horizontal position. The joints are overlapped with a calculation of 10 cm. The final fixation is done with a stapler. It is important to take into account that when further finishing is carried out, a ventilation gap of about 3-4 cm should be left. It is necessary to ensure drainage of moisture.

Hydroparage of interfloor overlappings

The material should be laid between the ceiling and its rough surface, as well as on the floor beams over the insulation. In this case, too, an enlarged clearance of up to 20 cm is made. To ensure the integrity of the barrier, the hydro-vapor barrier film for the floor is additionally fastened with a special tape. Such material is also supplied by insulator manufacturers and serves as a connecting element.

It is important to note that if the premises connected by an insulated floor-to-ceiling overlap have different temperature conditions, then it is necessary to select an insulating material with extended functionality. So, in addition to hydro- and vapor barrier, it is necessary to provide for the ability of the barrier to reflect heat flows. For example, similar qualities should have a hydro-vapor barrier film, which is planned to be laid in the attic or attic.

Hydro and vapor insulation of internal walls

When securing the frame walls from the inside, two tasks are performed: vapor barrier and an obstacle to the distribution of insecure insulation particles to the living quarters. The membranes are fixed from both sides of the insulation to the supporting bases in the form of racks and beams. Also, if possible, a water vapor barrier film can be attached to the surface of the rough finish. Installation is again done with a stapler or with galvanized nails. But in this case, the overlap should be at least 15 cm. If further walling is planned by lining or plywood, the insulation can be fastened with vertical wooden rails that have undergone antiseptic treatment. Also, between the trim and the membrane, a 3-4 cm gap remains.

How to choose the right hydraulic vapor barrier?

In the choice of any insulating material , the value of the construction that is planned to provide this protection increases. That is, for the beginning, the threats to the site of use are determined, and then a hydroparproof film is purchased. How to choose this material is not an easy question, several points should be considered in it. First you need to determine the origin of the membrane itself. Usually it is polyethylene. It is desirable to choose a perforated film, since it is the most durable. With the skillful installation with its help, it is possible to provide a durable and effective barrier in front of moisture and winds.

If the tensile strength is not a fundamental criterion, a flat water vapor barrier film can also be used. The price in this case will be low - a roll can be purchased for 1000-1200 rubles. If you buy a reinforced film with a metal layer, you should be ready to pay for it 2000-3000 rubles. But with its help it is possible to effectively provide not only functional isolation, but also strong.

Reviews about water vapor insulation

More recently, the negative factors, from which the means of hydro-vapor insulation are used, the builders and architects sought to exclude by selecting certain materials for structures and finishes. But this approach significantly limits the technological solutions. The use of insulating membranes, in turn, practically does not involve similar effects for the home. This, in particular, confirms the film "Taiwec solid" is hydroparoprotective, the reviews of which indicate the benefit from its application. Reducing the moisture content in the space between the finish and the rough coat, while maintaining the integrity of the thermal insulator, is only part of the benefits that the insulator provided.

Conclusion

For all its popularity, membranes for hydro and vapor insulation are still a relatively new invention. The first of this group of materials on the market was a heater, but its use in rooms with high moisture was ineffective and necessitated another protective layer - so there was a hydroparproof film. How to choose a suitable membrane and how to properly install it - these are the main issues that consumers face. And above them, the manufacturers of these materials are working hard, improving both performance and styling techniques. At this stage, companies can offer high-performance insulators that can not only keep the insulation from moisture, but also provide a strong barrier against precipitation and wind.