How to install a vapor barrier to a heater. Correct vapor barrier with your own hands. Vapor barrier device. Which side to lay. Concrete flooring with vapor barrier

A fairly common problem after warming a house is the lack of the expected effect of the work performed. It would seem that a traditional material was chosen, for example, mineral wool, everything is done according to building laws and canons, but it is still cold inside the room. The reason for this may be the lack of knowledge of the "experts" of elementary norms, including which side to lay the vapor barrier to the insulation. Let's take a closer look at this issue.

Vapor barrier is divided into two types according to the method of application:

liquid paint vapor barrier;
vapor barrier membranes (film).

The paint vapor barrier is applied with brushes and rollers in places where roll vapor barrier is difficult to apply, for example, on ventilation and chimneys. This family of vapor barriers is represented by materials such as bitumen, tar and tar.

Vapor barrier membranes

First of all, let's decide on the types of vapor barrier films for their purpose. In terms of their specifics, membranes used in construction are offered in the following design:

membranes with vapor barrier properties;
the membranes are vapor-permeable.

To protect the mineral wool from the effects of moisture on it from the inside, it is necessary to additionally lay a layer of vapor barrier. When insulating the roof, floor or interior of a house located directly below it, it is recommended to use an appropriate film. Note that the insulating layer is laid from below, under the laid mineral wool (from the side of the room).

If external wall protection is being used, the corresponding components should be free of perforations or pores.

Always pay attention to the value of the vapor permeability coefficient - the lower it is, the better. Plain plastic wrap is a great option. An ideal choice would be a material with additional reinforcement. The presence of a foil-clad aluminum coating will only be a plus.

Do not forget that the presence of a vapor barrier finish leads to a multiple increase in humidity in the insulated space, so you should take care of a good ventilation system in advance.

Special vapor barrier films are made with an antioxidant coating. Due to it, moisture does not accumulate. They are usually attached to components that are susceptible to rust formation. We are talking about metal tiles, corrugated board, galvanizing, etc. The rough fabric layer on the wrong side of the film ensures effective moisture removal. It is laid with the processed side to the insulation, and the fabric side outward, so that a distance of 20-60 mm remains to the mineral wool.

When insulating the walls of the house from the outside, a building membrane is used that can evaporate, protect the material from strong wind gusts. In addition, it is suitable for protecting pitched roofs, façades with a leaking base from moisture. Often, a vapor barrier film has very small pores and surface perforations, due to which water is effectively removed from the insulation into the ventilation ducts. The process is the better, the more actively the evaporation is carried out. This will allow the insulation to dry out quickly and efficiently.

There are the following types of vapor-permeable films:

Pseudo diffusion membranes, which transmit no more than 300 grams / m2 of vapor for 24 hours.
Diffusion membranes with a vapor permeability coefficient in the range of 300-1000 grams / m2.
Super diffusion membranes, with an evaporation rate of more than 1000 grams / m2.

Since the first type of insulation is considered to be good moisture protection, it is more often placed under the roof surface as an outer layer. Additionally, you will need to provide an air gap between the insulating layer and the film. At the same time, the specified component is not suitable for facade processing, since it conducts steam rather poorly. This is due to the penetration of dust and other debris into the pores of the membrane during dry time, the “breathing” effect disappears and condensation begins to accumulate on the surface of the insulating material.

The two remaining types of membranes have large pores, this eliminates the possibility of their clogging, due to which there is no need to leave an air ventilation gap in the lower part. As a result, it is not necessary to mount the crate and counter battens.

Three-dimensional diffusion films are commercially available. A ventilation layer is already provided inside the membranes, due to which moisture cannot reach metal surfaces. The specificity of the film device is similar to the antioxidant variant. The only difference is in the removal of moisture from the insulation. This is beneficial, since when the roof is tilted even at a slight angle of 3-15 degrees, the possibility of condensate draining through the bottom is excluded. Therefore, corrosion of the galvanized coating will gradually occur, followed by its final destruction.

Which side to attach the vapor barrier to the insulation

First you need to figure out where you may need to lay the vapor barrier membrane, and then decide on the side of the vapor barrier.

If the insulation is laid from the front part of the wall, then the vapor barrier film is fixed from the outside, this will be waterproofing.
Ceiling and roofing requires the use of an antioxidant vapor barrier. Bulk and diffusion coatings are often used. They are laid on top of the mineral wool according to the principle of ventilation facade organization.
In the absence of additional insulation of the roof and ceiling, the vapor barrier film is attached to the underside of the rafters.
Thermal insulation of the upper part of the ceiling of the rooms, the ceiling located under the attic space, requires laying a vapor barrier membrane on the lower side of the insulation.
When insulating walls and floors from the inside, it is recommended to additionally lay a vapor barrier film on the outside of the mineral wool.

Many "experienced" builders even have no idea how the vapor barrier membrane should be attached to the walls: the front or the wrong side.

The best solution would be to use material with the same seamy side and front side.

And what to do in the case of a one-sided option, in particular with antioxidant insulator? You need to know that the seamy side is the fabric surface located during laying in the interior of the room.

A metal plane turns in the same direction foil membrane- the shiny side to the inside of the room.

For any film vapor barrier materials the following rule applies: the smooth side is laid to the insulation, while the rough side should face the room.

The same rule applies to polypropylene steam insulators, which are laid with the smooth side to the insulation.

The vapor barrier is laid with the dark side to the insulation

It must be borne in mind that when the roll is rolled, for example, on the floor, the inner side must be on the floor.

In addition, most often the darker side is the outside.

Does the membrane need an air gap?

You should always leave it. On the underside of the films, a special gap up to 50 mm wide is arranged. This will avoid condensation on walls, floors and insulation. It is important to avoid contact of the surface cladding with the membrane. By using diffusion film for floors, walls or ceilings, you save yourself many problems, since you can fix it directly on a heat insulator, OSB or moisture-resistant plywood. A ventilation spacer is required on the outside of the membrane. In the version with an antioxidant component, the air gap should be within 40-60 mm on both sides.

Organization of a ventilation gap when laying a vapor barrier

If everything is clear with the walls and floor, then with the roof and ceiling the situation is kept apart. When performing a ventilation gap, additional installation of a counter-lattice based on wooden bars will be required. When organizing a ventilated facade, a gap is left when erecting horizontal profiles and racks located perpendicular to the wall and the film.

Video: ONDUTIS vapor barrier installation technology

How the vapor barrier is attached

Fixing the membrane to walls, floor or ceiling can be done using wide-headed nails or a construction stapler. However, the best choice would be to use counter rails.

The vapor barrier is laid with an overlap with an overlap of at least 10 cm. After fixing the vapor barrier, the joints are glued with special tape or tape for vapor barrier.

Conclusion

In conclusion, we say that membranes will allow any building structure to serve an extremely long time. Alas, it is impossible to achieve a positive ratio of moisture and temperature in other ways. In addition, do not forget about the rules for laying vapor barrier. Most manufacturers also distribute assembly instructions with the product. This is especially true for diffusion and superdiffusion membranes. Therefore, do not be lazy before purchasing to clarify all your questions with a sales assistant.

Vapor barrier is an important process that is carried out during the insulation of house structures. It allows you to protect thermal insulation materials from the negative effects of steam.

Some materials, when wet, lose their integrity and thermal insulation properties. Therefore, their protection must be approached very carefully. But, first of all, it is worth deciding what materials are used for vapor barrier, which side to lay them on.

In contact with

Why do a roof vapor barrier

Incorrect installation or lack of vapor barrier leads to rapid damage to the roof under the influence of negative environmental factors. As a result, it loses its integrity, which leads to a reduction in the life of the entire building.

How does a vapor barrier work? Roof vapor barrier allows you to protect the insulation from water vapor that comes from the interior of the house.

According to the law of convention, steam rises from the bottom up. As a result, it accumulates under the roof. The absence of a vapor barrier will cause steam to move further through the roofing cake. After cooling it turns into dew. It settles in heaters, which then leads to their destruction and loss of properties. This applies not only to thermal insulation, but also to the wooden elements of the truss structure.

Important! The device of a vapor barrier layer avoids the formation and accumulation of condensate in the layers of the roof.

Varieties of materials

Previously, it was used to protect the roof from steam only parchment. There is a wide variety of safety barriers on the market today. They differ in their price and technical characteristics. Therefore, in order to make the right choice, it is necessary to carefully disassemble everything. available options. Consider what each specific type is used for:

When choosing a vapor barrier material, there are a number of factors to consider. The quality and durability of the protective barter will depend on this.

Types of vapor barrier materials

Vapor control membranes are often installed in two layers... This allows you to maximally protect the roofing cake from moisture ingress. The type of material is important here.

Vapor barrier type A

Type A includes moisture and windproof materials that are able to optimally protect the insulation from moisture and weathering. The barrier is placed between the roof and thermal insulation. Used for vapor barrier of roofs and walls. It can also be used for ventilated facades.

Attention! The main task is to transmit condensate from insulation, if any, as well as preventing the ingress of moisture from the external environment. When carrying out work, the slope of the roof is taken into account.

Vapor barrier type B

Type B includes vapor barrier materials that are used as a vapor barrier in room. This allows you to protect the insulation from moisture coming from the inner space. The material is widely used to insulate walls, floors and ceilings in multi-storey buildings. As for the roof, here we are talking only about pitched structures.

Materials of this type consist from two layers. The first layer is made of sanbond. It prevents condensation from forming in the morning. Moisture is absorbed into it and disappears throughout the day.

As for the second layer, it is presented in the form of a vapor barrier film.

Vapor barrier type C

This type includes two-layer membranes that have a high density. Compared to the previous type, the film layer has great thickness. The materials are used in non-insulated and flat roofs.

Type C thermal insulation is widely used to protect basements and basements from groundwater. It is also indispensable when installing parquet or laminate floors.

Vapor barrier type D

The vapor barrier is presented in the form of polypropylene fabric, which has a laminated coating on one side. Type D material possesses high strength. It is widely used as a waterproofing layer, as well as in the construction of a non-insulated roof. In the latter case, this will protect the structure from possible leaks.

Vapor barrier membranes

A vapor barrier membrane for walls and other structures is a modern material that has certain properties. Among the advantages, it is worth highlighting high vapor permeability, long service life and strength.

Depending on the structure, membranes are divided into several types:

One-sided. The membrane conducts steam in one direction. Therefore, during installation, it is important to trace which side to lay the vapor barrier to the insulation.
Bilateral. Such a membrane can be laid by either side, as it allows moisture to pass from both sides.
Single layer.
Multilayer. They have high functionality and are used to solve various problems.

On the downside, membranes are quite expensive, especially when it comes to multilayer products.

Laying principles

When installing a vapor barrier, special attention should be paid to the question of which side to fasten the material. To do this, you need to carefully study instructions from the manufacturer. It contains all the information on which side to lay the vapor barrier to the insulation.

It should be borne in mind that the installation method directly depends on the variety:

Glassine. Lay on insulation from the inside. The bitumen-covered surface must face the interior of the room.
Single layer polyethylene films. It spreads from the inside of the heat-insulating layer on either side.
Reinforced polyethylene film. Stacked in the course of unwinding the roll.
Two-layer film. How to properly install this type of vapor barrier? Stays within pile out, smooth side close to the insulation.
Foil film. The shiny side is a heat reflector, so it should be directed towards the interior of the room.
Izospan, which side to lay? Its sides are painted in different colors, it is placed light on the insulation.

To know how to properly lay the vapor barrier, you must carefully study the instructions.

The air gap is arranged in any case. A gap is arranged at the bottom of the film, the width of which is is 5 cm. In this way, the formation of condensation on walls and other structures can be avoided. The main thing is that the membrane does not come into contact with the lining.

In the case of a roof, the implementation of a ventilation gap will require the construction of an additional counter-lattice. This also applies to ventilated facades.

Installation principles

Before starting work, you need to know how to properly fix the vapor barrier.

Preparatory stage

Initially, you need to choose a material. In this case, special attention should be paid to the features of the installation and its technical characteristics. After that, they proceed to the direct preparation of structures:

All wooden elements are processed antiseptics and fire retardants. This will protect against decay and increase their fire resistance.
Damp areas of concrete and block structures are treated with an antiseptic. This will prevent mold from forming.

If we neglect such work, then in the future this will lead to the destruction of structures. As a result, the service life of the building is reduced.

Ceiling installation

Ceiling insulation is carried out in buildings when insulating a pitched or flat roof. Also, such work is needed for thermal insulation of the basement and the rooms above which the attic is located. This applies to the bath. In any case, preparatory work is carried out at the initial stage.

When performing work, you need to follow some rules. Docking of materials should be carried out overlap. The length of the grip is at least 10 cm. In this case, the joints are carefully glued with special tape.

When laying the vapor barrier on the ceiling, it is also worth considering that the film should go onto the walls. Installation features depend on the design of the floor.

Laying on the floor

Now let's look at how to lay the vapor barrier on the floor. Algorithm of work looks something like this:

Dismantling old flooring and removing debris.
Hydro and vapor barrier of the subfloor is being laid.
Insulation installation.
Laying the second layer of vapor barrier.
Finishing floor padding.
Finishing finish.

When performing work, it is worth making sure that the film is laid correctly.

Laying on walls

The vapor barrier of the walls from the inside is carried out exclusively along the crate. Thus, the work is carried out according to the following scheme:

Arrangement of the frame.
Fastening the film horizontally along the entire plane.
Wall decoration.

When performing vapor barrier, it is worth adhering to some rules. In the process of fixing the film somewhat stretch... All joints are carefully glued with tape.

The mounting method directly depends on the material used and the design features. Fixation of polyethylene and polypropylene films is carried out using staples and small nails.

Attention! To avoid damage to the material, it is necessary to use the clamping strips.

Thus, the fastening of the membranes is carried out.

Useful video: which side to lay the vapor barrier

When performing vapor barrier work, special attention should be paid to the connection points. The overlap should be at least 10 cm. After that, the joint is glued with a special tape. It is recommended to use foil tape.

The vapor barrier is laid according to the manufacturer's instructions, where it is mandatory to indicate which side it should go. If there are no instructions, or there are no recommendations on the choice of sides, you can be guided by the general principles of installation.

Which side is used to put different types of vapor barrier:

Glassine. As a vapor barrier, it is laid from the inside on the insulation, with a black (bitumen-coated) surface inside the room.
Single layer polyethylene films. They are attached from the inside to the insulation by either side, since they do not have additional properties, but only perform the function of a vapor barrier.
Polyethylene films reinforced with a polymer mesh. They also do not have specific instructions for laying, it is convenient to lay them in the course of unwinding the roll.
Two-layer vapor barrier films (fluffy on one side and smooth on the other). They need to be laid with the pile out, close to the insulation with the smooth side.
Foil vapor barrier. Fastened with the shiny side inside the room, as it is also a heat reflector.

You should not use superdiffusion membranes as a vapor barrier - their function is to remove steam from the insulation, and not to prevent its penetration.

Which side to lay the vapor barrier on the floor

You can lay a two-layer vapor barrier on the floor with the fleecy side on the floor beams. This option is suitable for brick houses with timber joists so that the beams can breathe. If the film is fixed to the ceiling under the beams, the tree can "rot", which will lead to the formation of mold.

Which side to put on the roof

By placing the foil-clad vapor barrier with the shiny side into the room on the inside of the roof, you can reduce the cost of heating the room. If you use glassine under the roof, it will have to be laid in several layers with the black side inward - due to its rather high vapor permeability.

Which side to lay on the walls

Reinforced polyethylene films are attached inside the walls with either side to the insulation. They are preferable to ordinary polyethylene, as they are much stronger and, accordingly, easier to fix. Outside the walls, vapor barrier is not used; instead, vapor-permeable wind insulation (waterproofing) is used.

Although the vapor barrier is not the most important element of the building, the operational characteristics of the roof, attic and non-insulated basement, attic enclosing structures and multilayer walls of the building largely depend on it. How to carry out the installation correctly and which side to lay the vapor barrier film on?

What is it for

The vapor barrier is designed to prevent the formation of condensate on the inner surfaces of the roof, walls and floors, which can lead to the soaking of the insulation, and, accordingly, to a decrease in its thermal performance. The occurrence of condensation is explained by the ingress of warm water vapor obtained as a result of human activity on the cold surface of the wall or moisture condensation on them. The material retains water vapors and reflects their ingress into the room, eliminating the possibility of condensation.

For the correct installation of the vapor barrier, one should understand the physical nature of the phenomenon from which it protects the insulation and building structures.

Moisture vapors always tend to move from an area with high pressure (warm room) to an area of low pressure (environment), while passing through the insulation. Therefore, it is possible to protect the heat-insulating material by laying the film in the path of vapor movement, that is, between the heated room and the insulation layer. This rule applies to all structures, without exception, both for ceilings and for walls and floors.

Which side to install the vapor barrier film: correct installation

The domestic market of building materials today offers a large selection of film vapor barrier from various domestic and foreign manufacturers. At the same time, its individual types may have surfaces of different textures, therefore, read the manufacturer's instructions before installation.

And although it is easy to determine that when using for insulation of rooms with high humidity (steam rooms, bathrooms, etc.) films with one-sided coating with aluminum foil, the metallized surface should be directed into the room, for example, for the material "Izospan V" not everything is so clear. This film has a two-layer structure - a smooth and rough surface. The manufacturer's instructions note that a rough surface made with such a texture to keep condensate drops and their subsequent evaporation should be directed into the room, and a smooth surface should fit snugly against the insulation.

If the installation of the vapor barrier was carried out correctly, there will be no condensation inside

Features of attic insulation

the film is attached to the rafters from the inside of the attic with galvanized nails or a construction stapler, covering the insulation;
strips of material are laid horizontally, from bottom to top, with an overlap of one strip on another at least 15 cm;
in rooms with high humidity, the strips are fastened to each other with a special connecting tape;
fixation is carried out by attaching to the rafters of the frame, designed for attaching decorative panels or sheets of drywall.

In all cases, there must be a ventilation gap of 4 - 5 cm between the cladding and the vapor barrier!

How to attach a vapor barrier to the ceiling, floor and ceilings

When located under a pitched roof of an unheated attic, the overlap under it is subject to thermal insulation. In this case, the film is attached from below, to the load-bearing floor beams, and is fixed using elements of a rough ceiling or a finishing frame. It also requires a ventilation gap between the insulating layer and the finished ceiling to remove humid air.

When insulating a floor over a cold basement, the vapor barrier is placed on the floor beams from above, protecting the insulation from warm water vapors that tend to the basement, where the partial pressure is lower. To create a ventilation gap, the film is not stretched, but is placed between the beams on an insulation, the thickness of which is less than the height of the beams. Logs are nailed on top, and flooring is arranged along them - boards or a base for linoleum, carpet or other material.

Below are a few rules to keep in mind during installation:

vapor barrier is carried out in the enclosing structures that separate the heated rooms and the external environment;
always fits between the insulation and the cladding under the interior finishing;
The vapor barrier and interior finishing cladding should be separated by a ventilation gap to remove water vapor.

Compliance with these rules will minimize the possibility of condensation!

Installation of vapor barrier and insulation on the roof

Video: laying a vapor barrier film

A wide range of vapor barrier films and membranes produced by domestic and foreign manufacturers allows you to choose the material that best matches the temperature and humidity conditions of the room and the climatic conditions of the construction area. The correct choice of insulating material will make it possible to obtain the desired effect at minimal cost.

Ensuring a reliable level of vapor barrier in the house is a guarantee of maintaining a stable level of air humidity in relation to the outside temperature. Vapor barrier, unlike insulation, does not easily maintain the temperature, but protects the room from the effects of steam and the appearance of condensation. Many, when they begin to lay insulation and vapor barrier, wonder which side to put the vapor barrier on so that it works normally.

The question of which side to install the thermal insulation correctly is very important when preparing work. To understand which side you need to lay the vapor barrier film on the surface, evaluate the entire process of laying the walls, including the installation of insulation. And only then it will be clear which side, where, what needs to be put.

General description of the vapor barrier process

Prepare the substrate to be dry and clean by first covering it with a primer. The metal surface should be free of grease. A vapor barrier must be laid on the roof immediately.

On the floor and walls lay the insulation first, then waterproofing, and only then - a vapor barrier material, while the film should not be stretched tightly and not hang down.

Vapor barrier has the following advantages:

moisture evaporates faster;
regulation of the microclimate of the room on a par with insulation;
protection against fungi and mold;
increase in the service life of building materials.

Installation of vapor barrier materials is carried out in accordance with certain rules. To protect the insulation, the vapor barrier material must be placed on inside the room between the thermal insulation layer and the inner lining. Also, the correct installation of the vapor barrier depends on what material you are using.

So, the principle of operation of a vapor barrier is as follows:

To install a vapor barrier, regardless of the material used, materials such as are used:

wooden lathing battens;
metallic profile;
construction stapler;
self-tapping screws;
scissors for metal;
double-sided tape;
ordinary or construction tape.

Classification of vapor barrier materials

The material used for vapor barrier must be durable, have low thermal conductivity and be fire resistant. There is no universal material for this purpose; materials such as are used for vapor barrier:

Vapor barrier technology

The algorithm for installing a vapor barrier looks like this:

How to properly lay a vapor barrier on the ceiling

Ceiling, roof, floor and walls are subject to vapor barrier. Let's start by describing the process of installing vapor barrier materials on the ceiling.

The ceiling needs vapor barrier for a reason protection against negative impact water vapor, which is formed due to high humidity in the room. Household needs such as washing, bathing, cleaning, cooking and much more contribute to an increase in indoor humidity.

The warm air released as a result of these processes goes up and wants to go outside, but it stumbles upon the ceiling. And the vapor barrier will increase the service life of the materials for the roof, and it will also minimize the likelihood of mold and mildew in the attic. In addition, the ceiling will become more fire resistant.

To install the vapor barrier on the ceiling, you need roll material attach to the rough ceiling surface and press with a metal profile or crate. When you begin to roll out the rolls, stripes will appear, butt them to each other in an overlap of 10-15 cm. To seal the joints, use special self-adhesive tapes.

How to perform vapor barrier on floors, roofs and walls

It is necessary to isolate the floor from steam, first of all, on the ground floors above the basements, as well as in baths and saunas. The material is laid after installing insulation and waterproofing material. You need a film not too tight, but also prevent it from sagging. Then secure it with an overlap with double-sided tape or special staples.

Please note that the vapor barrier must be laid in two layers, on the bottom and outside of the insulation, as well as on top of it.

For vapor barrier in large rooms, you need to use liquid bitumen rubber. It is applied manually or by compressor. When it dries, an elastic rubber film appears in its place, which does not allow moisture to pass through.

And as a vapor barrier for the roof, it is best to use double-sided diffuse membrane... It should be installed from the inside and outside; the membrane must be placed on the insulating material itself without gaps. Bitumen can also be used, which is laid in rolls on top of the roof and fixed with counter battens.

Equipping the walls with a vapor barrier is much the same. The material must be attached to the wall along its perimeter with a stapler, while each of the panels should overlap with the other by 15 cm, they need to be glued together with construction tape. Thin slats are laid on top.

The sheet material is attached to a metal or wood frame. The barrier is fixed with self-tapping screws, and the joints are sealed with adhesive tape. Outside, the insulation works before the installation of the insulation, creating with it subsequently three-layer protection system.

So, as you can see, installing a vapor barrier is not as difficult as it might initially seem. Thanks to it, you will protect your premises from moisture and extend the life of building materials.