Vapor barrier of walls - reliable protection of the house from dampness. Why and how vapor barrier is done on the walls of wooden houses Material for vapor barrier of walls

Traditional material for building houses - this is wood. It began to be used in the distant past. In an effort to achieve environmentally friendly housing, modern man is increasingly paying attention to this material. But the installation process still became different. And it is precisely because of this that today we have to use additional building materials. These include vapor barrier for walls wooden house. We will talk about what it is and what it is used for in this article.

Why do you need a vapor barrier?

In the old days, a wooden house did not need additional insulation or finishing. Its thermal insulation properties were sufficient to provide between indoors and outdoors. The wood simply “breathed”, and that was enough.

Today, all work is carried out in accordance with certain requirements and calculations. Therefore, in addition to being environmentally friendly and attractive, a wooden house must also comply with energy saving standards. And this led to a change in the very concept of a “wooden house”. Currently, it is most often understood as a “pie” made of several layers of building materials.

Naturally, it is difficult for air to get through all these layers. Its free circulation is disrupted. The steam is trapped inside this “pie”. As a result, condensation forms and accumulates inside. As a result, it turns out that the insulation layer turns out to be damp.

Materials used for moisture lose their properties and become deformed. In addition, condensation causes the appearance of mold and fungi on the wood. As a result, the structure of the material is disrupted. The wood begins to “twist”, the joints of the logs are broken.

Understanding the above process necessitated the use of a protective layer. For this purpose, vapor barrier is used for the walls of a wooden house.

What does a frame-type wall “pie” look like?

To fully understand why vapor barrier is used for the walls of a wooden house, it is best to understand all the layers of the “pie”. If the house is being built frame type, then the “pie” looks like this:

• finishing of the premises;

• frame;

• insulation;

• insulating layer (from wind, moisture);

• exterior decoration of the house.

Vapor barrier for a wooden house is also performed to protect the structure from wind and moisture.

Construction of a building from solid logs

The use of logs changes the order of fixation of building materials, characteristic of frame-type buildings. In these cases, a vapor barrier is installed for the walls of a wooden house outside, and not inside.

An insulating layer is laid on top of the logs. Next, a frame for the insulation is constructed. For this purpose they most often use wooden beam. Next, the waterproofing layer is attached. A layer is laid on top of all this finishing. Any suitable building materials can be used as the latter. Their choice today is very large. It all depends on the preferences and financial capabilities of the building owners. For example, this is how a vapor barrier is attached to the walls of a wooden house under siding.

Types of vapor barrier

Several types of building materials can be used as a vapor barrier layer:

• A film made of polyethylene, which is only one millimeter thick. This is the simplest and cheap option. But he has one significant drawback. The fact is that the film completely blocks normal air circulation. As a result, the walls cannot “breathe”. Use this type material must be handled very carefully. It breaks easily. Don't pull it too hard. Otherwise, the inevitable seasonal expansion of materials may damage the film.

• Vapor barrier mastic perfectly allows air to pass through and retains moisture, preventing it from penetrating inside. It is applied immediately before finishing the room.

• Membrane film is the best option. The insulation is reliably protected from moisture, while air circulation is carried out in the required volume.

The most common vapor barrier for the walls of a wooden house is the third type. It is a protective membrane. Therefore, let’s take a closer look at its characteristics.

The best option

It is an innovative material that appeared not so long ago. Its main advantages are:

• Excellent protection against moisture penetration.

• Air passes through the membrane, which prevents the so-called greenhouse effect.

• Absolutely safe for people.

• Does not emit harmful and dangerous substances.

Even at the stage of selecting building materials, it is worth paying attention to the issue of membrane strength. To reduce cost, some manufacturers reduce this figure. When used, such a membrane breaks easily. And who needs damaged vapor barrier for the walls of a wooden house?

Which side to lay the membrane - another important nuance. It is necessary to strictly ensure that the vapor barrier lies exactly as required by the manufacturer. If you turn it the other way, it will not bring the desired effect.

Methods of attaching the protective layer

Timber can be used to build a home various types. Depending on this, vapor barrier for the outside walls of a wooden house can be attached in two ways.

The first is used in situations where the logs are round. Protective layer can be attached directly to the log.

For logs with rectangular or square section This option is not suitable. In such situations, a strip of about two and a half centimeters wide is placed on the log itself. An interval of about one meter is maintained between them. The vapor barrier is attached to the installed slats.

Using a vapor barrier indoors

Protection from moisture is provided not only from the outside of the building. A vapor barrier is also installed for the interior walls of a wooden house. The whole process will look like this:

• A wooden sheathing is attached to the inside of the wall. To do this, use bars five centimeters wide.

• Next, a layer of waterproofing is laid. In this case, a gap is formed between the wall and this film. It is necessary for room ventilation.

• Metal profiles are attached to the sheathing beams through the waterproofing.

• Insulation is placed in the cells formed between the profiles.

• Everything is covered from above with a vapor barrier membrane. She lays it all out. The joints are sealed.

• Completes the “pie” external cladding, which is covered with finishing.

A vapor barrier laid in this way for the walls of a wooden house indoors will prevent the appearance of condensation in the “pie”.

Things to remember during the installation process

It is very important to properly prepare the wooden wall before fixing the vapor barrier. To do this, all joints and cracks must be completely sealed.

WITH outside Buildings, vapor barrier material should not be fixed tightly to a wooden wall. It is necessary to maintain openings between the vapor barrier and the finishing. They are necessary for air circulation. Thanks to them, condensation from the film will leave naturally.

In the case of a frame house, the situation is exactly the opposite. Insulation does not require a rigid wall. It is attached between the beams from which the frame is assembled. As a result, two-thirds of the entire wall is insulation. Therefore, it must be carefully protected from moisture. Otherwise, the material will lose all its thermal insulation properties and other features. Deformation of the insulation will lead to the appearance of cracks.

Rules for installing a vapor barrier layer

Achieve maximum effect from use vapor barrier membrane Following some simple rules will help:

• The pattern on the membrane should be facing you, not the wall.

• Individual parts of the insulation are overlapped. They must be at least ten centimeters apart from each other.

• The material is rolled out only in the horizontal direction.

• All joints are sealed. To do this, they are glued with tape, the width of which should be more than ten centimeters.

• Elements that are complex in their design are also glued with tape: corners, niches, protrusions, window and door openings, and so on. All adjacent surfaces are taped with tape. This will improve the seal.

• It is necessary to provide a reserve of membrane near the windows so that the insulation is not damaged during deformation. The stock is made in the form of folds.

• The material must be completely protected from direct sunlight. This is especially true near window openings.

• The method of attaching the vapor barrier depends on the selected material. Polyethylene and polypropylene films are fixed with a regular construction stapler or nails. To prevent the material from being damaged, it is recommended to nail it using wooden planks. With their help, the vapor barrier is pressed against the sheathing. All this is fixed from above. The membrane is more stable and does not tear as easily. But it can also be secured in a similar way.

The most common mistakes

The vapor barrier will not perform its functions if the installation process was carried out incorrectly. The most common mistakes are:

• The installation was carried out sloppily. This means poorly sealed joints, the presence large quantity folds, mechanical damage to the material.

• The material was chosen incorrectly. When choosing insulation, you need to consider where exactly it will be attached: inside or outside. For example, only suitable for internal use.

• Double vapor barrier effect. Occurs due to non-compliance with installation technology. Some types of materials are attached tightly to the wall. For others, it is necessary to assemble the sheathing.

Manufacturers of vapor barrier materials

Very many modern companies produce vapor barrier films. The most popular of them include the following:

• "Utah" with trademarks"Yutafol" and "Yutavek" (Czech Republic).

• "Megaisol".

• DuPont and their Tyvek films (USA).

• "Houserep."

• "Fakro" (Poland).

• Dorken, which produces vapor barriers under the Delta brand (Germany).

• "Klober" (Germany).

The vapor barrier for the walls of a wooden house “Izospan” from the Gexa company is worth mentioning separately. This enterprise produces several types. They can be used indoors or outdoors, for walls or ceilings, for “pie” with or without insulation.

When building a house, a special place is occupied by the stage of protecting walls from moisture and steam. It is absolutely necessary to do this, because dampness can cause harmful fungus and mold to appear. To prevent this from happening, it is necessary to perform high-quality vapor barrier. We will consider below what materials are used for this.

The main task performed by the vapor barrier of walls is to prevent the accumulation of moisture in the insulation. Materials that allow air to pass through well are used to construct the thermal insulation layer. If moisture gets into the insulation and accumulates there, the insulation layer ceases to perform its functions. In places where moisture accumulates, wallpaper comes off the walls over time and deteriorates. plaster coating, fungus and mold appear. In the future, mold and mildew can spread throughout all the walls. It is very difficult to get them out later. In addition, fungal spores are harmful to human health.

Vapor barrier prevents moisture accumulation in the insulation

The installation of a vapor barrier layer is carried out in several cases:

1. 1. When insulating indoors. This is especially important if the thermal insulation is made of materials based on cotton wool. Glass wool and mineral wool are excellent thermal insulators; in addition, they allow the walls to “breathe” by allowing air to pass through. Their main drawback is that they absorb moisture. The more it accumulates, the worse these materials retain heat and the faster they become unusable. This can be avoided if the walls are vapor-proofed.
2. 2. For buildings with wall structures made of several layers. Multi-layering requires mandatory protection from evaporation and moisture. This is true for houses from frame structures.
3. 3. For external walls and ventilated facades. The vapor barrier in this case serves as additional protection from the wind. Its presence prevents air flows from actively circulating. Thanks to this, the exterior finish experiences less stress and performs its functions better.

Vapor barrier materials must allow air to pass through well

For vapor barriers, materials are used that prevent the penetration of moisture, but at the same time allow air to enter the premises through micropores. So that there is a vapor barrier maximum effect, it is necessary to arrange ventilation system, because natural circulation there won't be enough air. Along with high-quality ventilation, a layer of vapor barrier materials will protect the room from dampness. However, there are no universal vapor barriers that can protect any structure from the roof to the basement. Their choice depends on the material and design of the walls. If the humidity level in the room is normal, then there is no need for a vapor barrier layer.

Several types of materials are used to protect walls from damp vapors. Firstly, these are mastics. Such materials are applied directly to the surface of the wall, creating a layer that not only effectively protects against moisture penetration, but also allows the walls to “breathe”. Mastic is applied to the walls before construction finishing layer finishing with decorative materials.

Mastic is applied to the surface before finishing

Polyethylene film with a thickness of less than 0.1 mm is also used. This is one of the frequently used vapor barrier options. When installing a layer, do not stretch the film too much so that it does not tear. The disadvantage of conventional film is that it does not have perforations and therefore does not allow air to pass through at all. But now the industry has begun to produce perforated polyethylene, which is breathable, which allows you to create a comfortable microclimate in your place of residence.

The most profitable option is membrane film. It is similar to its polyethylene counterpart, but has several layers that effectively retain moisture, allowing sufficient quantity air. Membrane type films due to their operational properties provide maximum functionality of the heat insulator. When using them, the walls will not freeze or collapse, which extends the life of the entire building.

The most profitable vapor barrier option is membrane film

Membrane films are available in various types. In each specific case, you can select a vapor barrier that will demonstrate its properties most effectively during operation:

• When insulating the walls outside the building, Izospan with additives that increase fire safety, Megaizol A, Megaizol SD, is laid on top of the heat insulator.
• For internal use, "Megaizol V" is used - this is a polypropylene film made of two layers with an anti-condensation surface.
• For buildings with wet rooms, for example, baths and saunas, for which particularly high requirements are placed on vapor barrier, steam and waterproofing materials type "Izospan". Distinctive feature these materials – the presence of a reflective layer.

All polypropylene films should be reinforced with fiberglass.

Construction of a vapor barrier layer - learning the procedure

To properly perform a vapor barrier, you need to know that it is performed differently outside and inside the building. is carried out from the inside, so the vapor barrier is also laid with inside. On the ground floors and in the basement, the vapor barrier layer is installed from the outside. In swimming pools, vapor barrier is required on both sides; the installation technology is the same as for the basement floor.

Before thermal insulation works basement floor, the work surface should be prepared. It should be cleaned first, then applied protective covering. Liquid rubber is more complex in terms of application technology, as it requires the use of special equipment. The material consists of two mixtures, which, after mixing, instantly polymerize. Therefore, the solution is prepared immediately before use and applied using a two-torch gun that sprays liquids under pressure.

When installing a protective layer against water vapor with bitumen, the following steps are performed:

• The first layer is applied with mastic, which acts as a primer;
• then applied in two layers bituminous materials in the form of rolls or mastic.

For structures located above the basement and ground floor, vapor barrier of the walls is carried out indoors. When installing internal vapor barrier, a number of rules should be followed:

• first you need to install the sheathing;
• a heat insulator is placed in the sheathing;
• then the film is laid, and if it has a reflective surface, then the reflector should be turned inward;
• for tightness, the joints are glued;
• for polypropylene, a counter-lattice is installed;
• on final stage finishing is being done.

When installing a protective layer from moisture and steam, it is advisable to leave free space for air movement and removal of excess moisture.

Features of the technology for vapor barrier installation of frame and wooden buildings

In a house made of frame structures, insulation occupies a third of all walls, with a thickness of at least 150 mm, so it is absolutely necessary to install a vapor barrier layer. If the vapor barrier is weak, the insulation will begin to accumulate moisture, lose its thermal insulation qualities and begin to deteriorate. The vapor barrier is mounted on the frame and trim. It is attached using a construction stapler. The joints are sealed with tape or lubricated with mastic.

The vapor barrier of the walls is mounted on the inside of the insulation, thus creating a gap between the layers that provides the necessary ventilation, creating optimal microclimate.

For wooden buildings vapor barrier is also necessary. But it doesn’t happen right away. The fact is that when constructing houses from timber and logs, the fact is taken into account that the wood is dried to a certain extent even before construction, and it finally dries out during further use finished house. It is not recommended to perform a vapor barrier until wooden structures are completely dry.

In a wooden house, vapor barrier for walls can be internal or external. At external thermal insulation the vapor barrier is overlapped. The joints are sealed with tape. Next, a thermal insulation layer is installed, which must be protected with a waterproofing material. At the final stage, external finishing is performed.

If thermal insulation is carried out indoors, then the sheathing is first installed. It serves as the basis for the installation of a waterproofing layer. Next it is mounted on the wall metallic profile, on which the heat insulator is laid. The next layer is made of vapor barrier film. The joints should be carefully sealed with tape. Finally, the interior finishing is done.

Thus, we found out why vapor barrier is needed for walls. Its main task is to create an obstacle to the penetration of moisture and protect the insulation and internal structures. If you follow the technology and use the appropriate vapor barrier, the structures will be reliably protected from dampness and the life of the structure will be extended.

One of the main tasks at each stage of construction is to protect all structural elements structures from direct exposure to water. Its destructive power can negatively affect any construction material. But there is another, less obvious, but no less dangerous enemy - steam or moisture. Fungus, dampness and mold are the consequences of neglecting measures that can prevent the impact of these factors on the walls of the building.

Why is vapor barrier needed?

Vapor barrier is especially necessary in damp and at the same time warm rooms. For example, this applies to baths and heated basements, which are located below ground level and are therefore susceptible to dampness. Inside such buildings, steam is formed - warm air with water droplets, which requires a way out of the room. These paths become the walls and ceiling. Since in this case steam formation is a constant process, gradually the steam begins to destroy the surface building structures, which causes detrimental consequences for the home. Vapor barrier is the barrier that is designed to protect walls from steam penetration into them, and, consequently, their subsequent destruction.

Installing a vapor barrier is an event carried out not only for premises such as a bathhouse or basement. The need to carry out such work does not disappear even in cases where the building is insulated from the outside with a material with low diffusion resistance or the walls are constructed from a homogeneous material.

There is no universal vapor barrier material that works equally effectively for all building structures from the roof to the basement. Which vapor barrier to choose is determined by the structural components of the wall structure.

When is laying vapor barrier on walls necessary?

There are a number of cases when vapor barrier is mandatory:

• When insulating walls from the inside, especially if the thermal insulation is made of cotton-type materials. Mineral and glass wool have excellent heat-insulating properties; moreover, they belong to the category of “breathable materials”. However, cotton wool has a very important drawback - the fear of moisture, under the influence of which they become wet, lose their valuable qualities and are gradually destroyed. A vapor barrier installed indoors makes it possible to avoid these negative consequences.
• Multilayer wall structures V frame houses must necessarily contain a vapor barrier material. This case is similar to the previous one – structures with internal insulation.
• For ventilated facades and external walls, the vapor barrier layer plays a windproof role. Vapor barrier measures and softens the flow of outside air, protects external insulation from overloads and provides him with free “breathing”. An example of such a case would be Brick wall, insulated on the outside with cotton wool insulation and covered with siding. The vapor barrier, which plays the role of a wind barrier in this situation, prevents increased ventilation of wall structures. The ventilation gap serves to remove excess moisture from the surface of the windproof layer.

An important factor in ensuring a normal indoor microclimate, along with heat and vapor insulation, is the presence of effective, constant ventilation.

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Materials used for vapor barrier

The term “vapor barrier” does not mean that the barrier should not allow steam to pass through at all. Modern membrane materials capable of ensuring passage minimum quantity“controlled” air flow, which guarantees the absence of a “greenhouse effect” in the room. Excess moisture is retained by the membrane, and the air released from it is not capable of damaging the wall structure and insulation material. Insulation materials, equipped with an internal “coat”, transport the main flows humid air along the required path - through the exhaust ventilation system.

Types of vapor barrier materials:

• Polyethylene is considered a traditional vapor barrier material. During installation, it must be handled carefully, without pulling too much, so that the film does not break through seasonal changes in climatic conditions. However, if the polyethylene is not perforated, then it will not allow the passage of not only steam, but also air. It is simply impossible to create a comfortable microclimate in such conditions. And since polyethylene will not allow air to pass through, like a membrane material, it is not suitable as a vapor barrier.

Some forums advise perforating plastic film with a roller with nails or other devices driven into it. However, such a “modernization” of polyethylene is completely incapable of providing vapor barrier for insulation and building structures. Membrane materials are similar to polyethylene film appearance, but are radically different in their multilayer structure.

• One of the vapor barrier materials are mastics specially developed for this purpose. The mastic applied to the surface of the walls and ceiling will allow air to pass through and retain only moisture. Surfaces are treated before finishing.
• A new generation of vapor barrier materials are membrane films. They have the ability to stop moisture while allowing air to pass through. The membranes have a certain vapor permeability that is correct to ensure normal operation of the insulation. Cotton insulation with such a vapor barrier does not get wet or freeze, the walls “breathe”, maintaining their integrity and ability to perform their functions for a long period.

When using membrane materials, an air gap is often not required.

Common brands of membrane vapor barrier materials

Membrane materials are produced in a wide range. Moreover, each model is intended for a specific area of ​​use, where it can maximize the properties inherent in it:

• Vapor barrier materials installed with outside insulation external to the heated space - “Izospan A”, “Izospan A” with OZD (fire retardant additives), “Megaizol A”, “Megaizol SD”. These materials are used to protect the external walls of structures made of timber, panel, frame, combined buildings from snow, wind, atmospheric moisture for all types of exterior finishing - siding, lining, with external wall insulation.

It is important that the vapor barrier membrane fits tightly to the insulation and is securely fixed to the elements installation system, had no loose zones or sagging, which could cause “popping” under the influence of sharp gusts of wind.

• For installation indoors, use “Megaizol V” - a two-layer polypropylene film with an anti-condensation surface. IN winter time this material protects walls from the formation of condensation, fungus, and corrosive destruction of structural elements. "Megaizol V" also protects the interior space from insulation particles getting into it. Izospan V performs a similar function.
• Materials for hydro- and vapor barrier with a reflective layer - “IzospanFD”, “IzospanFS”, “IzospanFX” - are intended for vapor barrier installation in rooms with special requirements to their thermal insulation characteristics, for example, in baths and saunas.

Rules for vapor barrier of frame walls

It is especially important to do vapor barrier in frame houses correctly: install the membrane on the desired side, carefully fasten it to the studs with a stapler, glue the joints with special tape or coat them with mastic.

In cases where ecowool, polyurethane foam, polystyrene foam is used as insulation, and the room is arranged efficient ventilation, in frame structures you can do without a vapor barrier layer. If a decision is made about the need to install a vapor barrier, then it is possible to use one of two existing design schemes:

• According to the first scheme, the vapor barrier is sewn onto the frame posts. On top of the vapor barrier membrane, the room is lined with plasterboard, clapboard or other wall materials, intended for interior decoration. This option is most suitable for buildings that are intended for seasonal living and are not used in winter. These are dachas guest houses or workshops combined with a parking lot. With this option, effective ventilation of the room must be ensured.
• The second design scheme involves installing a vertical or horizontal sheathing on top of the vapor barrier membrane, providing an air gap of 30-50 mm from the wall. This design is suitable for houses permanent residence or long-term use in winter period, since in this case increased humidity forms inside the house.

Features of the vapor barrier device for the walls of a wooden house

Vapor permeability wooden walls significantly exceeds the similar characteristic of walls made of brick or stone materials and depends on the thickness of the logs or timber, the tightness of the grooves, and the presence of cracks.

Glued laminated timber used to construct walls is dried in production conditions before low level humidity, has grooves for sealing, low shrinkage and therefore steam enters the insulation in limited quantities.

The walls of buildings made of logs or beams with a natural moisture level are dried already during their operation. Over the course of 4-5 years, as a result of shrinkage, cracks appear, deformations appear, beams and logs change in size, and the tightness of the grooves is constantly compromised. During this entire time, interior decoration cannot be carried out in the house, since access to the grooves to restore their tightness will become impossible. In this case, there are two options. The first is to wait until the wood is completely dry. The second is to install a vapor barrier on the walls using, for example, membrane films “Izospan B”, “Izospan FB” or “Izospan FS”.

The vapor barrier of the walls should form a single vapor barrier circuit with the basement and attic floors.

If the work on installing a vapor barrier on the walls was carried out competently and professionally, then such a house will always be warm and cozy, and the walls will receive reliable protection from moisture. Detailed diagrams and photos of wall vapor barrier:

And if after reading the article you still have questions, we invite you to watch this video, in which experts will talk about why vapor barrier is needed and how to make it yourself:

Wood is a living material, it main feature- ability to breathe. In wooden houses there is a natural exchange of air, and steam from the interior easily goes outside without lingering in the wood. Today many owners wooden houses they try to further insulate their home, turning its walls into a multi-layered cake of thermal insulation, waterproofing and decorative finishing. In this case, an additional layer of such a cake should be a vapor barrier for the walls of a wooden house. From the article you will learn why it is needed, what material can be used for steam and waterproofing of the external walls of a log house, as well as methods for attaching the insulator.

Let's figure out whether a vapor barrier is needed for insulation? When a room is warm, water vapor always forms in it, and the warmer the air, the more vapor it contains. At a certain temperature regime, called the “dew point,” water vapor is converted into condensate. If there is a large temperature difference between the inside and outside of the house, the “dew point” moves to the wall of the house.

When air exchange occurs naturally in the house, steam freely leaves the room and goes outside. Now imagine that a multilayer barrier has arisen in the path of the steam. Condensation gets into the insulation and lingers there.

This happens day after day, and as a result, moisture accumulates in the heat insulator. The insulation is deformed, its heat-insulating ability decreases, moisture contributes to the formation of mold, fungi, rotting and destruction in the wood.

Avoid such unpleasant consequences allows a vapor barrier, which becomes a protective barrier on the path of steam, preventing moisture from entering the insulation.

To increase the heat-saving parameters of log and timber houses perform both external and internal thermal insulation. Insulating a wooden house from the outside is the most effective method, which is resorted to much more often than the internal one.

Regardless of how the insulation is performed, it is necessary to choose the right vapor barrier material. If thermal insulation is performed with unsuitable material, when insulating the inside of the house, the room may experience Greenhouse effect, and external insulation will be ineffective. Therefore, before choosing an insulator, you need to carefully study its characteristics.

The main criteria for choosing a vapor barrier material are:

1. Water resistance, i.e. the ability of a material to withstand a certain amount of liquid, the higher this indicator, the better.
2. Vapor permeability, maximum density of transmitted water vapor.
3. Waterproofness, this property is especially important for vapor barrier of facades and wet rooms: bathrooms, baths, saunas.
4. Temperature range recommended for this material.
5. Specific gravity. This indicator is measured in g/m2, the higher it is, the stronger the material.
6. Tensile and tensile strength.

Types of materials

Materials intended for vapor barrier of walls can be divided into four large groups:

• vapor barrier films.
• membranes;
• films with a foil layer;
• coating insulation.

The first group includes polyethylene and polypropylene films.

Vapor barriers made of polyethylene are usually used for reasons of economy, since, despite some advantages of PE ( inexpensive price and good moisture resistance), polyethylene film has a number of significant disadvantages:

1. Low strength, the film can be damaged during installation, and it can also become deformed during use.
2. Short service life.
3. In interior spaces a greenhouse effect can be created at home, so when using it, it is necessary to equip a forced ventilation system.

The film is destroyed when exposed to sunlight, which limits its use only to internal surfaces; it is often used for.

Polypropylene films are much stronger and more durable than PE films. The material is resistant to temperature changes and ultraviolet radiation. Today, films are produced from PP with a viscose and cellulose base; due to the inclusion of these materials in the composition, the absorbency of the film has increased by an order of magnitude.

Modern films used for vapor barrier of walls have a multilayer structure, which alternates layers with vapor barrier properties and a reinforced fabric, which adds strength and wear resistance to the film.

Please note that when using reinforced vapor barrier films, it is necessary to leave a gap for ventilation to facilitate rapid evaporation of moisture.

Vapor barrier membranes

The vapor barrier breathable membrane does not interfere with air exchange and improves ventilation of the wooden walls of the house. It is a non-woven fabric that forms a reliable protective barrier and does not allow vapors to penetrate into the insulation. There are single-sided and double-sided membranes, which respectively remove steam in one or different directions.

Foil material

This group of materials was specially developed for vapor barrier of baths, saunas and steam rooms, where conventional insulators are not suitable. On one surface of the film there is foil, which is reflective and at the same time reduces heat loss.

Foil materials include:

• metallized kraft paper;
• metallized kraft paper with mylar coating;
• fiberglass base with foil.

Foil film can also be used for thermal insulation of the walls of residential buildings, in which, thanks to the use of this material, heat loss is reduced by 10-15%.

Coating insulation

For basement walls and ground floors houses that are located in close proximity to the ground use mastics based on liquid rubber or bitumen. Mastic is an aqueous polymer solution that is applied with a brush directly to the walls of the house. After the composition has completely dried, a durable film is formed on the surface, protecting the wall from moisture and steam.

How is a vapor barrier performed on walls?

In wooden houses, a vapor barrier is usually located from the inside of the room, and hydro- and wind protection is located on the façade of the house. If the house is to be insulated from the outside under siding, lining or other finishing, a vapor barrier sheet is laid between the insulation and the wall of the house.

The wall pie for internal and external insulation is different. External thermal insulation, as a rule, are done in an old house to give it a more attractive appearance, while leaving wooden frame. Internal thermal insulation produced in new buildings after exterior finishing work has been completed.

Basic rules of vapor barrier

1. It is very important to monitor which side of the film is facing the insulation. The smooth side of the film should be on the insulation, the rough side should be on the outside. Foil films are laid with a shiny surface towards the room.
2. The vapor barrier must be laid with an overlap of at least 10 cm.
3. The joints of the panels are sealed with double-sided tape, the width of which is at least 10 cm.
4. Near the window openings, you need to leave a reserve of canvas for deformation of the material.

Vapor barrier of walls inside the house

When performing internal vapor barrier, so that an optimal microclimate is established in the room and does not result in reverse effect When moisture condenses inside the house, you must strictly follow the work technology.

Before starting work, it is necessary to prepare the surface of the walls, clean them of dust and dirt and carry out antiseptic treatment.

1. Wooden sheathing is attached to the interior walls. First install vertical racks on both sides of the wall, then in between. The width of the step between the slats depends on the size of the insulation and the type of interior finishing. For example, under plasterboard it will be 60 m; when covering with clapboard, a distance of 40 cm is sufficient.
2. Insulation is placed between the slats; it should lie very tightly to each other so that there are no gaps.
3. A vapor barrier is attached to the top of the insulation. The canvases are laid overlapping each other, gluing the joints with double-sided tape. Then the film is fixed to the wooden posts with a construction stapler.
4. Next, they install the counter-lattice to attach the finishing trim. The counter grille is necessary to create a ventilation gap between the sheathing and the insulation.
5. Finishing is carried out.

Laying vapor barrier on external walls

When insulating a log house externally, you can attach a vapor barrier directly to the logs without leaving ventilation gaps. Their function will be performed by the natural voids between the logs.

It is impossible to attach a vapor barrier directly to the walls of a timber house, since the circulation of steam will be disrupted.

Vapor barrier installation technology timber houses as follows:

1. The frame is made from wooden slats minimum thickness 25 mm, which are placed at a distance of one meter from each other.
2. Sheets of material are placed on the frame, fastening them together with a special tape. Additionally, the film is fixed to the wooden posts using a construction stapler.
3. A counter-lattice is mounted on top of the vapor barrier.
4. Insulation boards are laid inside the frame.
5. A hydro-windproof film is stretched over the frame.
6. Decorative finishing is being carried out.

Frame structures do not have a rigid base for attaching the material, so the technology for laying vapor barriers is somewhat different.

The frame house must have the following structure:

1. External cladding (lining, siding, etc.)
2. Water and wind insulation, which is installed with air gap in relation to exterior decoration.
3. Frame with insulation.
4. Vapor barrier membrane.
5. Wooden sheathing.
6. Internal lining.

This wall pie is ideal solution for a frame house.

You can do the vapor barrier of log house walls yourself, but if done ineptly, this will lead to numerous errors and problems. The subtleties of this work are known only to professionals.

The Master Srubov company is ready to provide its services to residents of Moscow and the region. We guarantee quality and fast work on insulation and vapor barrier of your home. To ensure that your home is always warm and cozy, contact professional craftsmen our company.

You can leave a request and contact us using the coordinates on the page.

The most important task in the construction of any building is to protect the entire structure from direct exposure to moisture. It is so destructive that it can destroy any building material. In addition to humidity, another serious enemy is known: steam.

When building houses, it is important to vapor barrier the house from the inside. This is due to the fact that humidity destroys any material over time.

If you neglect to protect against emerging steam, mold, mildew, and dampness will appear on the surface of the walls. That is why every home requires a vapor barrier from the inside of the walls.

Some features

It is simply necessary in the raw and at the same time warm rooms. A striking example maybe a sauna, maybe a heated basement. Such rooms are located underground and are most susceptible to damp attacks.

In such rooms steam always forms in the form warm air, With a huge amount tiny droplets of water. The resulting steam simply needs to find a way out of such a room. He looks for ways and finds them in the form of the walls of the building, its ceiling.

In this case, the formation of steam becomes constant, destruction of building structures occurs, and the building becomes unsafe. To protect the walls of the building, a special vapor barrier is made, which prevents steam from entering from the inside, as a result, the life of the walls and partitions is extended.

Installation of vapor barrier is not limited only to baths and basements. Install a vapor barrier interior walls It is also necessary in buildings that have external insulation, when the walls have a homogeneous material.

It must be said that there is no special vapor barrier material that is suitable for all rooms equally. The type of vapor barrier depends on the existing structural component of the internal wall structures.

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Situations when it is necessary to install internal vapor barrier of walls?

Vapor barrier of walls must be done in several cases.

Mineral wool is a breathable material, but with this type of insulation, vapor barrier is simply necessary.

1. If the walls have mounted internal insulation. Moreover, the thermal insulation material was used mineral wool. Mineral wool from the group of “breathable materials” shows excellent thermal insulation properties. But she has one thing negative property, mineral wool is not friendly with moisture. It quickly gets wet, its properties gradually deteriorate, and it begins to quickly deteriorate. To prevent such cases from occurring, they are used from inside the building. Frame houses, having wall structures consisting of several layers, must certainly contain a vapor barrier material. This also applies to structures with internal insulation.
2. A powerful windproof function for buildings with a ventilated facade is performed by a laid vapor barrier layer. It produces dosage and softening of the air flow. As a result, the outer insulation is less overloaded, it gains free “breathing”. For example, a wall made of brick, which has external insulation made of mineral wool insulation and covered with siding. In this case, the vapor barrier becomes a kind of wind barrier; it reliably protects the walls of the building from powerful blowing. The existing ventilation gap removes excess moisture from the installed windproof layer.
3. To ensure a good microclimate in the room, it is necessary, together with vapor barrier, to install effective and reliable ventilation that operates in a constant mode.

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What materials do builders use today to lay vapor barriers?

However, the expression “vapor barrier of walls” does not mean that such a protective barrier does not allow any vapor to pass through. The membrane materials that builders use today are endowed with the ability to pass a certain amount of air flow. This is done for one purpose only.

There should be no “greenhouse effect” in the room. The installed membrane retains excess moisture and air passing through it; it will not have a negative effect on the internal walls of the house and the installed insulation material. When thermal insulation has an internal “coat”, the flow of wet mass is directed through the exhaust ventilation.

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Types of vapor barrier materials

The classic vapor barrier material is polyethylene. This material requires careful handling, since if the film is stretched too much, it can tear when climatic conditions change. But there is one very important condition. Polyethylene must be perforated, otherwise it will not allow air to pass through, in addition to steam. It will not be possible to obtain a comfortable microclimate in the building with such a film. If this polyethylene is used as a membrane, it will interfere with the flow of air mass; it cannot be used for vapor barrier.

You can perforate polyethylene film special device. Take a roller with nails driven in. Such “modernization” of polyethylene film will not be able to provide reliable vapor barrier internal walls. Of course, membrane materials are very similar plastic film, but they are very different from it in their multilayer structure.

Builders often use special mastics as vapor barrier materials. After application, such mastic is capable of allowing air to pass through while retaining moisture. Surface treatment with such mastic begins before finishing begins.

Membrane films have become a modern material that is used today when laying vapor barriers.

This material is able to prevent moisture from entering, while at the same time allowing air flow to pass through. Such membranes have a certain vapor permeability, which provides normal work insulation. When such a vapor barrier is installed, the cotton insulation does not get wet, the walls “breathe”, and there is no freezing.