Which vapor barrier to choose for a cold attic. Roof installation with a cold attic

The temperature difference between inside and outside the house leads to the formation of condensation, which settles on elements of building structures and layers of insulating material. It is especially important to prevent moisture from entering wood buildings. Prolonged exposure to water leads to wood rotting and loss of performance. To avoid negative phenomena, let's look at how the ceiling vapor barrier is installed in a cold attic, in warm rooms and what materials are used for this.

The main purpose of the material is to prevent moisture from entering building elements and structures. Most often, the phenomenon occurs in unheated rooms, for example, in attics located above living rooms. Ceiling vapor barrier is also important in a warm attic, where the membrane prevents the penetration of moist air from the inside and the settling of water on the insulating material.

The materials do a good job of ventilating layers of insulation. The structure of the products allows air to circulate freely in the insulation layers and structural elements, thereby removing excess moisture.

Additional properties of waterproofing materials:

• protection of floors from deformation and rot;
• increasing the service life of the structure;
• increasing the thermal efficiency of all layers of the insulating “pie”;
• increase fire safety buildings;
• maintaining a favorable microclimate in residential premises.

There are several types of materials designed to protect the ceiling from moisture and condensation. You need to figure out what exactly is suitable so that the waterproofing of the ceiling in a private house is carried out taking into account all the requirements of the owner.

Types of materials for arranging vapor barriers and scope of application

According to the principle of action they differ:

1. Standard materials. They are used for fastening from inside the room along the floor plane.
2. Products with a foil reflective layer. Additionally, they reduce heat loss in rooms by reflecting heat back into the room.
3. Controlled products. This material is laid out on top of the insulation, placed closer to the ceilings and has partial vapor permeability, due to which moisture is not retained in the insulation layers. Installation of materials with controlled action is necessary in temporary buildings in the absence of a stable cycle of moisture formation, when it is important to choose products with quick elimination water molecules through the membrane coating.
4. Membranes with variable vapor permeability properties, laid above the insulation. The features of the products help moisture evaporate from floors and insulation layers, but at the same time prevent condensation from penetrating into building structures.

Let's figure out which vapor barrier on the ceiling with a warm and cold attic is better suited. Materials differ according to the type of raw materials from which they are made:

• Glassine. The raw material is high-density cardboard impregnated with bitumen. Used to protect against water and condensation, can be mounted on a plane on either side. Availability is a plus, but the disadvantage is a short service life.
• Polyethylene. Has the highest resistance to water and moisture. They cope well with installation tasks between a cold attic and a bathroom or kitchen. If you need material for rooms under the attic without heating, it is better to prefer a film with a reflective layer. In order for the film to serve for a long time, you should choose reinforced 2-layer materials that are too tough for rodents.
• Polypropylene. Film products that are resistant to UV rays and tear resistant. Use is indicated for buildings where protection from sun rays, this usually happens during breaks in construction work in the warm season.
• Standard membrane. Performs steam and water protection functions. Products are produced with one-way permeability, so steam passes outside, but cannot get inside (back). The effect is achieved by the structure of the pores: narrow at the bottom and wide at the top. When laying the membrane, it is important to choose the right side for laying: the narrow part of the pores towards the insulation, and the wide side up. Manufacturers offer 1 or 2-layer membranes that have the same efficiency, but the latter are considered more economical.
• Breathable membrane fabrics. Difference from standard material the fact is that the sheets do not need to be laid out, leaving a ventilation gap between the insulation and the insulation - this increases the thickness of the “pie”. Breathable membranes can be laid without a gap, end to end, and the property of removing steam and condensate from the insulation is fully preserved: the membrane removes steam to the outside, not allowing it to return into the thickness of the insulation.

Depending on the type and properties of the products, the material and vapor barrier scheme for the ceiling in a heated or cold attic are selected.

When should you use ceiling waterproofing?

The material is designed to protect structures from moisture. High-quality waterproofing of the ceiling against leaks from above is required in private buildings, where it has not yet come to repairing the roof and multi-story residential buildings in the kitchen, bathrooms. Installation of waterproofing is required not only in residential premises with high levels of humidity, but also in open spaces (loggias, balconies), in rooms with no or variable heating - attics, basements. The materials protect decor and furniture, minimize the risks of the formation of fungus, moss, mold, and failure of electrical wiring due to short circuits.

Types of waterproofing for ceilings and scope

In houses multi-storey type The easiest way to waterproof the ceiling is from inside the premises. The most varied materials in composition, type and type of application are used.

Let's consider the properties and types of waterproofing products:

1. Adhesive based materials. These can be polymer products: polyethylene, vinyl plastic and non-polymer products - fiberglass, roofing felt, roofing felt. The use of materials is limited by the complexity of installation and the use of a burner. It is most convenient to install insulation on balconies and loggias.
2. Penetrating ceiling waterproofing. Considered one of the most convenient options for multi-storey buildings due to the long service life of the protective layer. The mixture is applied to a damp surface; during the wet process, the active components are converted into insoluble crystals, forming high-quality protection for the ceiling against leaks. Application is indicated on concrete surfaces, the composition fills all cracks, microscopic cracks and increases the strength of structures by 15-20%. The mixture is also considered safe for health and does not limit air exchange processes in the premises.
3. Coating materials. There are bitumen-polymer, cement-polymer, bitumen-rubber. Low cost, lightness and ease of application are advantages. The insulation is laid out layer by layer, in 1-2 layers, then be sure to plaster the coating.

On a note! 1 and 2-component coating materials are available for sale. Products are used for sealing cracks, seams, defects on ceilings, walls and floors in rooms with high humidity, without heating or with periodic heating.

1. Plastering. Special compositions for waterproofing include additives and polymers that give the mixture water resistance. After hardening, a smooth surface is obtained that prevents the penetration of moisture. Plasters are suitable for processing concrete and brick structures. It should be applied to a previously leveled and dried base.
2. Powder formulations. They are a mixture of resin, cement, and plasticizers. The powder is diluted with water and applied to a dried base. Waterproofing is rarely used, as it quickly deteriorates due to mechanical stress. The group includes paints and varnishes, gels, bitumen and rubber emulsions, as well as compositions based on latex and other waterproof elements. Pros: economical consumption, affordability. Cons: short service life. Can be used on any surface, including wood.

The last option is water repellents. New material universal type, suitable for any type of base. Application technologies differ: by painting or in the form of a plaster layer. The result is a water-resistant elastic coating that protects the ceilings from moisture. Advantages: ease of use, versatility.

When ensuring insulation of a private house and insulation of the roof along the rafters, one must not forget that Special attention should be given to a place like the attic.

Development of insulation attic floor mineral wool

Warm air tends to rise to the top, and therefore, in a temporarily unheated room, heat can escape through the cold attic space. Therefore, the issue of insulating the attic must be resolved without delay.

1 Why do you need attic floor insulation?

Insulation of a cold attic floor with stone or mineral wool, according to by and large needed in lightly used rooms that are properly equipped with special roof ventilation.

The attic, or rather its ceilings, serves as a kind of boundary between heat and cold. In such places, the attic floors are exposed to intense moisture due to the formation of condensation.

However, you can properly insulate the floors in the attic of a house with mineral wool with your own hands. The very process of insulating the floor in the attic with mineral wool is the creation of a durable thermal insulation coating, which will have a low degree of thermal conductivity.

The technology itself for insulating mineral wool floors in the attic, as well as Energoflex thermal insulation for pipes, implies strict adherence to its stages and requirements.

The technology itself is quite simple and understandable. Good thermal insulation of the attic floor using mineral wool Helps close unwanted gaps.

To do this, the insulation must be laid tightly. In most cases, mineral wool is used to insulate the attic of a house.

The presented insulation is the most suitable for this type of work; it can also be used to insulate the floor surface in the living areas of the house.

Schematic insulation of the attic floor with mineral wool

By organizing good insulation with mineral wool, the most optimal temperature will be maintained in residential premises.

If the procedure is performed incorrectly, moisture rising from the floor of the house will lead to the formation of condensation.

It will accumulate on the ceiling and then seep through the ceilings. The resulting temperature difference in those areas where the attic floors adjoin the walls of the house initiates the formation of mold and microscopic fungi, which can be causative agents of allergic diseases.

1.1 Requirements for attic insulation

The process of insulating the attic floor and insulating the roof of a house with your own hands, or rather the level of its quality, has a direct impact not only on the size of heat loss, but also on the service life of the entire truss structure and roof covering.

The fact is that water vapor located inside the heated room diffuses to the attic of the house. In order for the insulation used to provide a high degree of calculated efficiency of the thermal insulation layer, it must always be dry.

Based on this, the insulation must be protected from excessive humidification by vapors of rising heated air using a special vapor-proof material.

If the attic space is well insulated, it will not only provide high-quality thermal insulation, but will also help increase the service life of the entire roofing structure.

If there is no vapor barrier, steam will penetrate through the unprotected attic floors and condense on the floor surfaces.

This will lead to moisture flowing onto the rafters, which, under its influence, will begin to slowly rot from the inside.

As a result, the likelihood of destruction increases roofing pie. The thermal insulation performance of the structure is also reduced due to the fact that the tightness of the vapor barrier layer has been compromised.

Before insulating the attic, you need to drain the layer and remove moisture from the entire attic space. To do this, ventilation should be done through windows. They can be:

In order to ensure maximum ventilation intensity, the indicator of the total area of ​​all ventilation holes should be equal to 0.2-0.5% of attic floors.

If all work is carried out correctly, then winter period Icicles will not form on the roof. The process of insulating the attic space itself is carried out not from the living quarters, but from the attic floor.

This is the most convenient way to lay insulation, the choice of which depends on the technology used and design features buildings.

1.2 Features of insulation of beam floors

When implementing such an insulation scheme using mineral wool, heat is retained in the space between the beams. Their usual height is almost always enough for this, but if necessary, several bars are packed on top.

Insulating the ceiling with mineral wool from the attic side

The lower part of the ceiling is sewn up using molded material, as when insulating the attic of a private house. For this, lining or sheets of plasterboard can be used.

The subfloor covering is laid on top of the beams. This can be a tongue and groove board, plywood sheet or OSB board. Mineral wool is placed on a previously prepared special vapor barrier layer.

An alternative can be an ordinary film made using polyethylene. If the vapor barrier material is foil-coated, then it is laid with the shiny surface down.

The intermediate distance between the beams is filled with mineral wool with the required thickness parameters. The surface of the beams must be equipped with an additional insulating layer.

This will lead to blocking the so-called cold bridges and will significantly reduce the overall level of heat loss. If timber was used to create beams High Quality, then the finishing material spreads directly onto their surface.

Mineral wool is placed between them as when insulating a roof using polyurethane foam, and the attic floor is laid on top. The use of this technology is especially important in houses that are made of logs or beams.

Important with high degree to reliably protect mineral wool from the smallest drops of moisture, this is especially true if the roof has minor coating defects that cause leaks.

The layer of mineral wool must be reliably protected from the effects of wind from the eaves. For this purpose, mineral wool slabs with a high degree of density are used.

2 Why is mineral wool used to insulate an attic?

In most cases, when insulating attic floors, the consumer's choice falls on mineral wool. Its advantage is that its installation does not require special skills.

Mineral wool has excellent thermal insulation properties. Its structure consists of thin glassy fibers, the length of which ranges from 2 to 60 millimeters.

Insulating the attic with mineral wool

High sound insulation characteristics are ensured due to the presence large quantity air pores

These pores are located in the space between the fibers and can occupy 95% of the total volume of the insulation. Mineral wool is presented in three varieties; it can be basalt glass and stone.

Basalt wool is made using molten basalt rocks, to which binding elements are added.

This may be a carbonate type rock, which regulates the acidity level of the substance, which entails an increase in the service life of the insulation. Glass wool exhibits high heat-resistant properties and can withstand temperatures up to +450 degrees Celsius.

2.1 Technology for insulating attic floors with mineral wool

When carrying out work related to mineral wool, it is important to comply with all safety requirements and regulations.

This is due to the fact that in the process of cutting and laying such material, the air is filled with tiny particles that can enter the respiratory organs and thus cause harm to human health.

During installation, be sure to ensure the availability of personal protective equipment. Goggles, a respirator and thick rubber gloves must be available.

The process of insulating attic floors begins with the choice necessary tools and additional materials. You can't do without:

The essence of insulation technology is that the insulation must be carefully laid in the space between the attic floors or beams.

To enhance the thermal insulation qualities, reliable vapor barrier protection should be used. Warm and moisture-saturated air will continuously rise from the living rooms and reach the top through the ceiling.

There, in the under-roof space, it will collide with a layer of insulation. Due to the fact that mineral wool is generally considered a vapor-proof material, it will absorb all the outgoing moisture inside itself.

If it is left without the necessary access to air and sunlight, it will gradually dry out and, ultimately, lose all its heat-insulating qualities.

The attic is cold interfloor covering 20 cm min of cotton wool

In order to avoid such destructive consequences, it is necessary to lay steam under a layer of mineral wool. insulating material.

Before starting the main work, you will need to carefully calculate the required amount of insulation.

The amount of cotton wool purchased depends on how many layers are planned to be used when covering the attic space. In addition, the thermal insulation thickness parameter directly depends on the climatic conditions in the region.

Insulating the ceiling of a cold attic with mineral wool

Insulating the ceiling of a cold attic with mineral wool - advantages. Features of insulation of cold attic floors with mineral wool.

Source: uteplimvse.ru

Cold attic

The device of the so-called cold attic is used in a significant number of pitched roofs of private residential buildings and baths. This is due to a number of advantages provided by such constructive solution. The main advantage is that, despite the presence of the word “cold” in the name, such an unheated attic can significantly reduce the heat loss of the building.

The installation of a cold attic is the simplest solution from a technological point of view, especially when compared with the alternative warm option or the construction of an attic. The air temperature of such a room, as a rule, is slightly higher (no more than 4 degrees) than the air temperature outside.

The composition of the structure under consideration includes the following elements (from top to bottom):

• roofing;
• external attic walls;
• insulated ceiling between the attic and the living space underneath.

It should be noted that insulating the ceiling of a cold attic with mineral wool or other thermal insulation material can be done both from above and below from the side of the living room, regardless of whether it is wooden or concrete.

The option under consideration has a number of advantages:

• reliability of waterproofing of the coating. It is achieved by reducing the number of superstructures protruding above the roof, which, as a rule, are its weakest points;
• ease of operation. The existing internal under-roof space makes it easy to inspect and maintain all floor and roof structures;
• overlap area is less than area pitched roof, the area of ​​possible heat loss is correspondingly reduced;
• availability of additional operational premises.

In order for the benefits of a cold attic design to be fully manifested, it is necessary to correctly and competently resolve several issues related to the insulation of the attic floor, as well as proper ventilation cold attic.

Organization of ventilation

The main purpose of ventilation in this case is as follows:

• removal of excess water vapor penetrating through the ceiling from below from the residential part of the building, in order to prevent the appearance of condensation and wetting of the insulation and rafter system roofs;
• creating an optimal microclimate.
• Ventilation occurs through two types of vents:
• cornices (the air passing through them is called supply air);
• ridge (exhaust air passes through them).

Their total area should be 0.2-0.33% of the roof covering area, in other words for a covering area of ​​1000 sq.m. The area of ​​the vents should vary from 2 to 3.33 sq.m. This calculation is carried out in accordance with SNiP standards, and it is quite simple to do. He treats the same various options roofing pie covered with metal tiles, corrugated sheets or soft tiles.

The basic rule for the location of vents is as follows: the most efficient work ventilation system with the maximum distance between the inlet and outlet openings.

In most cases, a scheme is used with an approximately uniform arrangement of vents around the perimeter of the building under the overhangs and along the entire length of the roof ridge.

Additional ventilation is often performed through dormer windows installed on the gables or roof slopes, which help with enhanced ventilation. When installing them, they are guided by the rule of symmetry: in order to prevent the presence of unventilated areas, dormer windows should be located on opposite slopes.

Typically, dormer windows are made of three types:

They are installed in such a way that the lower part of the window is no more than 1 meter from the floor level, and the upper part is at least 1.75 meters higher from the floor level. Often, dormer windows are used as an exit to the roof for the purpose of inspecting the roof and the elements of the ventilation system and chimneys installed on it. Sometimes a special hatch is installed for this purpose.

In order to prevent birds from entering, the vents are equipped with protective nets or gratings, and blinds are installed on the dormer windows.

Thermal insulation options

The cold attic design can be used in buildings of any number of floors. One of the prerequisites for its normal operation is high-quality insulation of the floor. It is performed in one of two ways:

• from the attic side;
• from the inside from the residential part of the building.

Thermal insulation from the attic

This option is considered the most effective. A wide variety of ceiling insulation for a cold attic can be used: mineral wool (the most commonly used option), polystyrene foam, expanded clay, etc.

Sequence of work stages:

• vapor barrier device (ordinary PVC film or modern materials, having much higher performance characteristics);
• laying mineral wool thermal insulation in two layers;
• Creation protective coating from cement bonded particle boards.

This unit is one of many possible ones that fulfill the basic requirements for insulating the ceiling of a cold attic and allow you to obtain the following advantages:

• due to the presence of a vapor barrier, moisture does not enter the insulation;
• the DSP coating allows you to move freely without damaging the insulation;
• the design is quite reliable and durable (to further increase the service life, it is recommended to treat the surface of the DSP with antiseptics, which significantly reduce the likelihood of fungi or mold appearing).

It is imperative to additionally insulate the perimeter of the attic. It is carried out by laying a layer of mineral wool 0.75-1 meter wide and a layer thickness of 10 cm. This will reduce or completely avoid the risk of freezing in the upper floor rooms in the corners.

Thermal insulation from inside the living room

Installing a ceiling in a private house with a cold attic and insulation from the inside is done much less frequently, since the work is accompanied by a number of disadvantages:

• the ceiling level decreases;
• Carrying out thermal insulation work disrupts the finishing, if it has already been completed, and requires subsequent repairs;
• not all thermal insulation materials are useful and environmentally friendly, which leads either to an increase in the cost of work or to a decrease in living comfort. For this reason, the use of mineral wool is not recommended. In addition, it is always recommended to leave a ventilation gap between the thermal insulation material and the finishing material.

Thermal insulation from the inside is often carried out in parallel with the installation of suspended ceilings.

One of the most common methods of insulation from the inside is the option using extruded polystyrene foam (penoplex):

• First, the sheathing is installed, onto which the drywall will subsequently be attached. The thickness of the sheathing beam should be 2-3 mm greater than the thickness of the insulation, and the sheathing pitch should be 1-2 mm less than the width of the penoplex;
• after this, the insulation is secured between the sheathing bars with additional fastening with dowels to the ceiling;
• as finishing suspended ceiling plasterboard or suspended ceiling is attached.

There are many other possible ways to insulate a ceiling, but despite all the differences in the technologies and materials used, the basic principles must correspond to those given above.

Conclusion

The installation of a cold attic, if the work is carried out competently and the technology requirements are met, is an effective and expedient design solution.

Insulation, ventilation and vapor barrier of the ceiling of a cold attic in a private house

How to properly insulate, ventilate and vapor barrier the ceiling of a cold attic in a private house and what is the best insulation to use?

Source: www.hugebuilding.ru

Roof installation with a cold attic

Most pitched roofs in our country have a cold attic in their design. This name is due to the air temperature in the attic, which should not differ much from the air temperature outside the house. With this arrangement of the attic space, a sufficiently large buffer air zone is formed, which allows you to effectively regulate the temperature in the attic if it is properly arranged.

Cold attic design

When building the roof of a house, many people think about making a cold attic or attic underneath it? The easiest way to organize a roof is with a cold attic space. Construction of an attic will cost several times more and require more labor.. Although, it is undeniable that the attic will significantly expand the living space.

Cold attic roofs have the following main components in their pie::

1. roofing;
2. attic external walls (applicable for gable roofs with gables);
3. insulated ceiling between the living space and the attic.

Ventilation is provided by eaves and ridge vents. The air passing through the eaves openings is called supply air, and the air leaving through the ridge is called exhaust air. Additionally, ventilation can be done through dormer windows on the gables or roof slopes. The windows are equipped with louvered grilles to allow the ventilation intensity to be adjusted.

Dormer windows are located on opposite slopes of the roof so that there are no unventilated areas.

Dormer windows can be rectangular, triangular and semicircular in shape. Their lower part should be at a height of no more than 0.8-1.0 m from the floor of the attic, and the upper part should not be lower than 1.75 m from the floor in the attic. They can also serve as an exit to the roof of the house to inspect the roof, ventilation and chimney elements.

Steam and thermal insulation of a cold attic

For a roof with a cold attic, it is most important to minimize heat loss through the attic floor. For both wooden and reinforced concrete floors, a vapor barrier is mandatory. It is laid on the ceiling itself and protects the insulation from vapors that can condense in the heat insulator after passing through the ceiling of the living room. Slabs and slabs can be used as insulation bulk materials. The ceiling pie consists of a vapor barrier, floor beams and insulation.

The following types of heat insulators are often used in ceiling coverings::

• expanded polystyrene and foam boards;
• mineral wool slabs or mats;
• expanded clay granules;
• fuel or granulated slag;
• sawdust with lime or clay;
• pumice.

The thickness of the required insulation layer is selected depending on the estimated winter temperature using the table below.

Winter temperatures are calculated according to SNiP 2.01.01-82 (building climatology and geophysics) or selected by regions of the Russian Federation from the corresponding climate maps.

The insulation is laid between the joists or ceiling beams, and a boardwalk is made on top for the attic passages. Joists are usually 50 mm thick, and decking boards are 25-35 mm thick.

For ventilated attic spaces Soft or semi-hard heat-insulating materials are considered the most optimal.

Attic waterproofing device

Waterproofing roofs with a cold attic, according to many experts, is a controversial issue. Some say that waterproofing must be present under roofing material, and someone categorically recommends abandoning it. Here, a lot depends on the type of roofing material and the angle of inclination of the roof slopes.

Metal roofs are most susceptible to corrosion, which occurs due to possible small leaks or condensation. Therefore, we once again draw your attention to the fact that ventilation plays one of the main roles in the fight against condensation formed.

For gently sloping metal roofs Experts recommend installing superdiffusion membranes. It will prevent moisture from entering the outside of the roof when snow or rain blows in. No matter how well the roof is laid, there is always the possibility of minimal leaks. That is why, by paying a little extra, you will receive additional protection from moisture getting on the insulation in the ceiling of a cold attic.

Possible leaks or condensation entering hydrophobic insulation materials significantly reduce their thermal insulation properties.

If, for example, slate is used as a roofing material, then waterproofing can be abandoned. There is also corrugated sheeting with an anti-condensation coating on the market, which can hold up to 1 liter of water per 1 m2. For our part, we recommend always using waterproofing membranes, because this is the cheapest and easiest additional way to protect your roof from possible leaks.

When installing waterproofing membranes use a counter-lattice. It serves as a fixing strip and, due to its height, provides the necessary clearance for ventilation of the under-roof space. The installation of lathing in a cold attic is no different from insulated roofs. The dimensions of the sheathing and its pitch determine the type of roofing being installed.

Cold attic temperature

To prevent ice and icicles from forming on the roof, it is necessary to maintain the correct temperature and humidity conditions in the attic. If the thickness of the thermal insulation material is insufficient, significant heat losses through the ceiling. Warm air, heating the roof covering, causes snow to melt and ice dams to form. By choosing the right insulation layer, this can be avoided.

The effectiveness of a heat insulator can be assessed by measuring the temperature of the top layer of insulation. Digital Thermometer immersed in insulation by 10-20 mm.

As you can see, the design of a cold attic pie is not particularly complex in design. The main task is to ensure the necessary intensity of ventilation and the thickness of the thermal insulation layer in the ceiling.

Cold attic: ceiling pie, device, ceiling vapor barrier and waterproofing

Construction and design of a cold attic pie. Vapor barrier for ceilings and waterproofing in a cold attic. Optimal temperature for the attic.

Source: vseokrovle.com

Vapor barrier for ceilings in wooden floors: technological rules for installation

In order to reduce heat loss through building construction, they are equipped with a layer of thermal insulation. Almost all types of insulation require protection from penetration atmospheric water outside and household fumes from inside. The construction of a vapor barrier cannot be neglected, because this component of the insulation system plays no less a role than waterproofing. It is especially important to know how a vapor barrier is constructed for a ceiling in a wooden floor, since materials that are extremely sensitive to excess water are used in its construction.

The role of vapor barrier in construction

However, if there were violations during the construction of a house with insulation systems technological rules, water will begin to linger in the enclosing structures. At best, the result will be increased heat loss, a feeling of eternal cold and dampness. In the worst case, destruction or damage to structures is coming, dictating mandatory major repairs.

Steam protection of attic floors

According to the requirements of building regulations, in winter, the temperature within a cold attic should not exceed that outside by more than 5 - 6º C. The rules outlined in SP 17.13330.2011 state that in order to equalize the temperature and humidity parameters inside and outside the attic, it is necessary to arrange natural type ventilation.

Specifics of the vapor barrier device

• Glassine

Vapor barrier for ceilings in wooden floors: vapor barrier in wooden house

How to install a vapor barrier for a ceiling in a wooden ceiling, rules for choosing and using a vapor barrier film in the insulated structure of a wooden house.

Source: krovgid.com

Insulating the attic with mineral wool

Regardless of whether the attic is heated or not, it needs to be insulated. If this room is non-residential, then insulation of the cold attic floor with mineral wool is carried out between the load-bearing floor beams. If the attic is provided heating system and people will live there, then insulation is laid between the roof rafters. When choosing mineral wool, pay attention to the composition of the binder. It may contain phenol formaldehyde, which is poisonous. It is better to take acrylic-based materials.

Insulation of a cold attic with mineral wool

A vapor barrier is placed under the mineral wool.

To insulate the ceiling of a cold attic with mineral wool, you can take material of any density, from low to high. At the same time, it is still preferable to choose lighter materials so as not to create additional loads on the beams. Some experts are inclined to believe that glass wool is better suited for insulating an attic with mineral wool than stone wool. The latter is too brittle, and it weighs a lot.

As you already understand, insulation of a cold attic of a private house with mineral wool is carried out by laying thermal insulation between the load-bearing beams directly on the rough ceiling of the first floor. Due to the high hygroscopicity of mineral wool, it is necessary to use a vapor barrier film. In principle, even simple polyethylene can be used. There will be no special loads on the film and if installed carefully it will not tear. To be completely confident in the reliability of the protective layer, you need to use a polypropylene vapor barrier reinforced with fiberglass mesh.

Insulating the attic with mineral wool, technology:

• the supporting beams are sewn up from below - this is the rough ceiling of the first floor;
• on the attic side, a vapor barrier is laid on the rough covering;
• Mineral wool is placed on top of the film.

Vapor barrier tapes should be laid overlapping, the joints should be taped double-sided tape. The mineral wool is placed outward so that there are no cold bridges at the junction of the insulation with the beams.

Insulating a cold attic with mineral wool is always preceded by calculating the thickness of the thermal insulation. In any case, the layer will be at least 10 cm. Mineral wool is available in a thickness of 5 cm. It is better to lay thermal insulation in two layers with offset joints. This will eliminate the possibility of heat loss through the joints of the mineral wool sheets.

After insulating the attic floor with mineral wool, you can immediately lay the floor on top of the beams. It is advisable to first cover the insulation with waterproofing - a material that does not allow water to pass through, but at the same time allows steam to pass through, but only in one direction. It is important not to confuse which side to lay the waterproofing on, otherwise moisture will accumulate in the mineral wool, as a result of which the thermal conductivity of the material will increase significantly.

It is quite possible to use a fireplace for heating country house. To do this, a heat exchanger is built above the firebox.

Insulation of a heated attic with mineral wool

If the attic is heated and it belongs to the living space, then it is already an attic. Naturally, it also needs insulation. In this case, the thermal insulation is not laid between the floor beams, but between the roof rafters. At the same time, there are two methods for insulating an attic with mineral wool.

Let's consider the first option - laying thermal insulation between the rafters from the roof ridge to the ceiling of the first floor. In Fig. 1 the area where the insulation is applied is marked in red. Remember that you need to insulate not only the attic, but also a small section of the first floor, which is marked in green. As you can see, this option solves both problems at once. Installation method (layers from the inside):

• vapor barrier - stapled to the rafters. It is laid with overlap and tension. The joints are sealed;
• mineral wool - placed by surprise. You can use glass wool of any configuration (mats, slabs, rolls) or basalt wool in slabs with a soft end;
• waterproofing – three-layer polypropylene diffusion membrane. The tapes are laid horizontally and overlapping, starting from the edge of the roof;
• counter-lattice - the cross-section of the bars depends on the length of the roof slopes;
• finishing coating.

In terms of functionality, vertical tubular heating radiators are no different from horizontal ones.

In this article you will find information about plate heating radiators: characteristics, types, installation methods, operation and maintenance.

The second method of how to insulate an attic in a private house with mineral wool is somewhat different (see Fig. 2). The insulation is installed on the attic floor. Next, the wall is insulated according to the principle thermal insulation frame house . Also, the insulation is laid on the ceiling of the first floor from the attic wall to the end of the building. It is important that the insulation lays down without breaks, that is, it should move from one surface to another and preferably without joints. If there is a connection point, then the thermal insulation must be pressed tightly against each other.

With such an installation, undoubtedly, more material will be used, but in the long term there is a benefit. You will not have to heat unused housing square meters, therefore, the cost of heating the house will be somewhat lower.

Today we figured out how to properly insulate an attic with mineral wool and came to the following conclusions. If the attic is unheated (cold), then the insulation is placed between the floor beams. If the attic is heated, then thermal insulation is placed between the roof rafters. There is a method of laying thermal insulation on the attic floor, then the wall itself is insulated and then a section of the first floor floor from the wall to the edge of the building. This approach will slightly reduce heating costs, since there is no need to heat extra square meters.

For work, it is better to use glass wool, since it does not break and, after compression, restores its previous shape. It is lightweight and does not overload the load-bearing floor beams and rafter system. If you use stone wool, then you need to take slabs with a soft end so that they can be inserted between the guides at random. A vapor barrier is laid between the heated room and the insulation. When laying thermal insulation on the roof, you also need waterproofing, which is placed with outside. There must be a ventilated gap between the waterproofing and the finishing.

How to properly insulate the ceiling of a cold attic with mineral wool

On the ceiling of a cold attic in a private house, mineral wool is placed between the beams. A heated attic is insulated in two ways and each of them is correct.

Source: utepleniedoma.com

Vapor barrier is practical solution problems with ceiling condensation in houses with a cold attic. The material prevents the penetration of moisture, protects floors from condensation and further destruction, and also prevents the appearance of mold and mildew in insulation boards.

Features of the design

Cold attic includes surface gable roof with roofing material and an insulated ceiling separating the living space from the attic. To ensure ventilation, the attic is equipped with dormer windows, without which the air exchange in the attic will be disrupted, which will lead to the formation of condensation on the roof.

The floor of the attic is the ceiling, which also serves as the ceiling of the living space. When street temperatures drop, the ceiling becomes susceptible to the appearance of condensation, the formation of which is caused by the temperature difference between its lower and upper parts. To prevent droplets of condensation from penetrating into the ceiling, the top is covered with special materials that do not allow water to pass through.

In addition to protecting the base from moisture, the material performs an important thermal insulation function, preventing warm, moist air from rising upward. This technology significantly reduces heat loss in a living space and allows significant savings on heating. Vapor barrier must be performed on all types of foundations, including concrete and wooden floors. Isover slabs, glass wool or bulk materials can be used as insulation.

Types of materials

Before the advent of modern polymers, high-fat clay was used to vaporize the ceiling in a cold attic. Its disadvantage was its rather large weight and labor costs during installation. Today, the construction market offers a large selection of vapor barriers, differing in release form, installation method, properties and cost.

Film vapor barriers

Film vapor barriers are the most popular and in demand type, which is represented by polyethylene and polypropylene films and membranes:

• Polyethylene is the most widely used. This one is inexpensive and practical material reliably prevents the penetration of steam, but has restrictions on use. It is recommended to use this type of film only in warm climates under moderate temperatures: under the influence of extreme influences it quickly loses operational properties and is destroyed. The disadvantages include the low strength of polyethylene, which can lead to ruptures of the material even at the installation stage. Glassine, often used as a vapor barrier, is very similar in its properties to polyethylene: it also retains moisture well, but does not allow air to pass through at all.

• A more practical type of vapor barrier is polypropylene. This film tolerates thermal shocks well and is highly resistant to ultraviolet radiation. The service life of this material is several times higher than that of polyethylene. Modern technologies allow the production of film with the addition of viscose and cellulose. This significantly increases the strength and hygroscopicity of the material. A prerequisite for using such a vapor barrier must be the presence of good ventilation.

The water accumulated and retained by the pores of the material must evaporate freely, otherwise the properties of the material will be disrupted, which will lead to moisture in the ceiling.

• The most modern and practical type of vapor barrier material is membranes. The insulator is designed in such a way that the ability to pass steam is possible only in one direction. Thanks to this property, moisture is quickly removed, and air is exchanged between the ceiling and the attic room. In the domestic construction market, the most famous is the Izospan model, the fleecy structure of which is capable of retaining condensate droplets and quickly evaporating them. Installation of a membrane coating requires the formation of a ventilation space designed to provide room for liquids to evaporate.

Foil materials

This type is intended for use in conditions high temperatures and is used in the construction of baths as a vapor barrier for wooden floor beams. The insulating material is a film covered on one side with a thin layer of foil. Thanks to this structure, the material is able to reflect thermal radiation and retain steam well. There are several varieties of it:

• The most budget option is foil kraft paper. The material fits well, but during long-term use it is susceptible to the appearance of mold and mildew. The disadvantages include its low hygroscopic properties.

• Dacron coated kraft paper can withstand temperatures up to 140 degrees. This allows it to be used as a vapor barrier material in the construction of baths. The disadvantages include low resistance to chemical compositions of detergents.
• Foil fiberglass is considered the highest quality vapor barrier, and is characterized by increased strength and for a long time services. The downside is the high cost of the material.

Liquid products

Liquid means for providing ceiling vapor barrier are represented by varnishes and mastics. The compositions are applied to the surface of the ceiling and, after complete drying, form a thin film that can retain moisture and allow air to pass through. This promotes good ventilation of the floors and significantly reduces the likelihood of mold and mildew.

Some liquid products are intended for use only in non-residential premises and upon contact with them can cause harm to health, therefore, when using them, personal protective measures should be observed

Compliance with simple installation rules and operating standards will help to significantly extend the service life of the vapor barrier.

• The film material should be secured using staples or small nails, placing a thin wooden strip under the fasteners. This will allow the material to be better pressed to the base and will reduce the likelihood of accidental damage to the film.
• The size of the overlap when installing any materials should not be less than 15 cm. The joints should be glued using a wide tape, and when installing materials made of foil, you should use foil tape.

• Laying vapor barrier materials should only be done with thermal insulation.
• During installation, it is recommended to carefully control the tension of the material: the film should be in a free position. This will prevent the material from rupturing when it is stretched and compressed under the influence of thermal changes.
• To form insulation for the ceiling of a residential building, it will be sufficient to use a membrane or reinforced polypropylene film, and during the construction of bathhouses only foil vapor barriers should be used.

Vapor barrier is one of the prerequisites for the construction of houses and baths with a cold attic.

Properly selected material and proper installation will extend the service life of the ceiling, significantly reduce heat loss and make staying in the room pleasant and comfortable.

For more information about ceiling vapor barrier, see below.

If an apartment or private house has an unheated and, accordingly, cold room above the ceiling, homeowners may encounter an unpleasant problem - the formation of condensation on the ceiling surface. To avoid this disaster, in a cold attic, a vapor barrier on the ceiling is essential. What it is and how it can solve the problem will be discussed in this article.

What is it and why

Vapor barrier is a specially laid material that does not allow moisture to penetrate into the structure protected from it. To put it simply, it is a thin film through which water cannot penetrate. In a ceiling situation, it prevents warm, moist air rising from leaving the room. To create a vapor barrier layer in different situations, you can use different materials:

• Plastic film or glassine
• Special films with membrane effect
• Liquid mastics and varnishes designed to create a vapor barrier layer
• Foil types of insulation

Some of them simply create an impenetrable barrier and prevent water from entering the insulating layer or settling on the cold surface of concrete floors. Other vapor barriers are capable of allowing some air to pass through, but retain moisture. Films with a layer of foil applied prevent moist air masses from passing through them and have another function - they reflect some of the heat back into the room.

Polyethylene and glassine

These insulating agents create a barrier that is impermeable to moisture. However, they not only prevent water from getting into the insulating layer or getting on cold floor structures, but also prevent air circulation. Therefore, in a room with polyethylene or glassine as insulation from moisture on the ceiling, it is necessary to install a ventilation system to ensure normal air exchange.

There are not too many advantages of such insulators, but to be precise, there is only one thing - price. Both polyethylene and glassine are very inexpensive. At the same time, polyethylene lasts quite a long time, while glassine is characterized by fragility and rapid wear.

Membranes

This - special materials with limited breathability. They allow air to pass through, but retain moisture. The most common and popular vapor barrier of the Izospan brand has a characteristic feature - a fleecy surface on which tiny drops of condensate accumulate, which evaporate quite quickly.

The cost of such materials will be higher than that of polyethylene with glassine, but the efficiency of moisture removal is much higher, and air exchange remains within the normal range. At the same time, there are certain features of the installation of such membranes - to remove moist air vapors, a ventilation gap is necessary. Therefore, installation of the decorative ceiling covering from the side of the room is carried out on a sheathing or frame, which will create the necessary space for ventilation.

Liquid coatings

A fairly new solution, created thanks to the achievements of chemists. Looks like regular varnish or mastic. It is applied to the surface in the same way as conventional paints. After drying, a special coating is formed that can allow air to pass through, but prevent the passage of water vapor. Such materials are often used to vaporize the ceiling on the cold attic side.

In addition, this will be a very effective solution if flat roofs are treated in buildings that do not have an attic. In this case, a suitable insulation is laid on top of the applied insulation and the entire structure is waterproofed. In some cases, such materials may be harmful to health and can only be used in non-residential premises. Be sure to familiarize yourself with the characteristics of the selected paintwork material.

In order to reduce heat loss through building structures, they are equipped with a layer of thermal insulation. Almost all types of insulation need to be protected from the penetration of atmospheric water from the outside and household fumes from the inside.

The construction of a vapor barrier cannot be neglected, because this component of the insulation system plays no less a role than waterproofing. It is especially important to know how a vapor barrier is constructed for a ceiling in a wooden floor, since materials that are extremely sensitive to excess water are used in its construction.

The role of vapor barrier in construction

Building structures from the inside are constantly affected by steam flows released during mandatory household work, breathing of household members, hygiene procedures, etc. The penetration of water suspended in the air into the systems that enclose and insulate a house negatively affects their technical and operational properties.

On surfaces moistened with steam, colonies of fungi settle at a brisk pace, rendering almost all types of building materials unusable with amazing speed. Wooden elements rot and collapse. Wet insulation loses about half of its insulating qualities, because... The water contained in it significantly increases thermal conductivity.

Warm air, saturated with water suspended in it, always rushes to where the pressure and moisture content are lower. In our northern latitudes, for most of the year, the temperature and humidity parameters inside buildings are significantly higher than outside them. This feature explains the direction of movement of vapor-containing air masses moving from indoors to the external environment.

The predominant volume of evaporation, according to its own physical nature, is directed upward to “exit” into the atmosphere through the enclosing systems. The most active air currents that include steam “attack” ceiling, upper wall segment and roof structure. It is they who need to be strongly protected from the penetration of water in the air.

The process of air masses flowing into areas with lower pressure and water saturation is called diffusion. There is nothing particularly scary about it if no mistakes were made during the construction of building structures. Humid air simply will not penetrate the thickness of the insulating pie or move outside without causing damage to the structure.

However, if during the construction of a house with insulation systems violations of technological rules were made, water will begin to linger in the enclosing structures. At best, the result will be increased heat loss, a feeling of eternal cold and dampness. In the worst case, destruction or damage to structures is coming, dictating mandatory major repairs.

Steam protection of attic floors

The function of the vapor barrier film in a thermal insulation cake is to prevent water suspended in the air from penetrating into building structures. This means that it is the vapor barrier that must stop evaporation, so as not to let it pass at all, or to reduce it to minimum values something that managed to get through it.

We have already found out that in our regions, steam, along with the air flow, most often moves from buildings to the outside. Only in summer heat Reverse current is possible. The vapor barrier layer should be the first in the path of moist air. Consequently, it is laid on the side of the used premises before thermal insulation.

The installation of a vapor barrier along the ceiling is carried out if the attic is not intended to be heated. In this case, there is no point in insulating the attic space at all, because... it will not be used at all or will be used as a cold warehouse.

True, it is still necessary to protect the materials of the sheathing of the slopes and rafter frame. Waterproofing is installed against external influences, and a ventilation system is installed against the formation of condensation occurring due to the difference in temperatures inside and outside the structure.

According to the requirements of building regulations, in winter, the temperature within a cold attic should not exceed that outside by more than 5 - 6º C. The rules outlined in SP 17.13330.2011 state that in order to equalize the temperature and humidity parameters inside and outside the attic, it is necessary to arrange a natural type of ventilation.

This means that it is necessary to provide the roof structure with vents, dormer windows, aerators, etc. The total area of ​​ventilation openings, regardless of their type and purpose, should be on average 1/300 of the floor area or horizontal projection of the roof. The described measure is quite sufficient to maintain the temperature and humidity balance specified by building regulations.

Specifics of the vapor barrier device

Materials with the lowest vapor permeability are used as vapor barrier protection for the attic floor. This characteristic indicates the ability to conduct evaporation in a certain volume per unit area, indicated in mg/m² per day. All building materials have it to a greater or lesser extent.

Despite the ability of wood to freely allow evaporation to pass through, excess exposure to moisture is undesirable. Natural organic matter is unstable in linear dimensions, when moistened it expands. Naturally, this property is usually taken into account by designers, but excessive movements of the elements of wooden structures do not benefit them, and moreover, they often lead to rotting.

For normal operation ceiling located under a cold attic, it is necessary to correctly arrange the components according to their ability to pass humidified air. The component with the minimum ability to conduct steam should be placed first, then with vapor permeability greater than the previous one.

Therefore, for a steam protection device, materials with the ability to transmit steam close to zero or equal to fractions of one are mainly selected. Note that it can be several dozen, but must be less than that of thermal insulation. Even taking into account the fact that wood has a fairly high ability to conduct steam, the material for the device to protect against it should not allow more than a few tens of mg/m² of vapor to pass through per day.

The diagram of an insulated wooden floor, when viewed from the side of the premises being equipped, should look like this:

• Vapor barrier. A layer made of glassine, diffusion membrane, polypropylene or polyethylene film. During construction it is laid on top of the ceiling. When performing repairs, it is installed on the ceiling from the side of the rooms, glued or secured with slats.
• Thermal insulation. A layer made of backfill, roll or slab types of insulation. Most often it fills the space between floor beams, less often it is laid on top of the floor on a rough flooring or screed. If the attic is not intended to be used, then the thermal insulation is installed without waterproofing and wind protection.
• Waterproofing. A layer made of a diffusion membrane or perforated polyethylene. Installed only in the case of attic use, placed under the flooring or flooring.

If you do not plan to use the attic, then there is no need to install waterproofing on top of the insulating layer. It is transferred to the slopes, where it does the job of protecting the entire roofing system from atmospheric water. The insulation layer over the ceiling also does not require wind protection, because The enclosing structure itself protects from heat blowing out of its thickness.

To service the roofing system, ladders are installed within the unused attic. They are laid directly on the joists if slab or roll material is used. The drains are installed on legs if the insulation was formed by filling with expanded clay. Insulation materials laid loosely in the attic must be periodically “loosened” so that caking does not reduce the insulating properties.

Technological subtleties of laying a vapor barrier

The vapor barrier layer under the insulation is laid in the form of a pallet with peculiar sides extending onto the walls. Those. so that this barrier is not only between the ceiling and the thermal insulation, but also between the insulation and the parts of the walls in contact with it. Cover protective material obliged every beam or wall panel.

Laying of vapor barrier material on the ceiling is carried out:

• With a bend around each beam. The material “without interference” is laid in longitudinal strips perpendicular to the beams with a recess into the space between the beams. The opening of the vapor barrier is carried out taking this circumstance into account. If the length of one strip is not enough, the panels are glued together.
• With wrapping from the inside of each compartment of the box-panel floor. The material is cut into pieces corresponding to the size of the shield and the height of its walls.
• With laying on top of the rough flooring or with fastening with inside to the ceiling, if insulation is carried out in order to increase the insulating properties of the structure during the period of repair.

Regardless of the floor plan, the vapor barrier for the ceiling under the attic in a wooden house should form a continuous carpet that does not allow water to pass through or conducts it in a minimal amount. To do this, panels of rolled material are laid with the overlap specified by the manufacturer, the size of which is indicated in the instructions, and glued to each other with single- or double-sided tape.

The vapor barrier material should be rolled out over the ceiling as it was wound by the manufacturer. There is no need to turn over or rewind anything. In order not to confuse the sides of the installation, the manufacturer designates the side in contact with the ceiling.

How to choose suitable material

It is important not only to install the vapor barrier correctly, but also to choose the most suitable material for its installation. Tandem vapor barrier - the insulation must work perfectly, preventing the possibility of the thermal insulation cake getting wet.

The most ancient version of the steam protection device is fatty clay, which was used to treat the ceiling from below or above. Paired with clay, a dry soil-vegetative layer was used to prevent the penetration of hot air in hot weather and cold air in cold weather. Instead of soil, fine peat, shavings, sawdust, dry leaves and similar materials can be used.

Instead of outdated insulating varieties, materials specially designed to protect against steam and heat loss are now used. Their installation is much easier and significantly faster. However, in terms of insulating properties they are inferior to old proven methods.

For the installation of vapor barrier protection for attic floors, the following are now used:

• Glassine. A budget option with a vapor permeability of about 70 mg/m² per day. It is used mainly in domestic buildings that do not require an increase in humidity levels above standard values.
• Films made of polypropylene and polyethylene. Vapor permeability is measured in units, approximately 3 – 5 mg/m² per day. Most of these are reinforced materials that are resistant to temperature changes, mechanical stress and UV radiation. Suitable for furnishing wooden floors under the fill insulation.
• Vapor barrier membranes with foil shell. Vapor permeability averages 0.04 – 2.55 mg/m². They are used for arranging rooms with high humidity and unstable temperature conditions: saunas, steam rooms, Russian baths, swimming pools, combined bathrooms.
• Anti-condensation diffusion membranes. Their ability to transmit steam varies over a wide range from 3 to 15 or several tens of mg/m². These are the newest varieties universal purpose. In a used attic floor, thermal insulation can be installed on the bottom and top sides.

Anti-condensation varieties are available as double-sided polymer membranes. On one side, which should be facing the steam, they are rough, which prevents the formation of dew. The opposite side is smooth, it prevents the penetration of moisture from the outside.

Video about the rules for installing vapor barriers

An example of laying vapor barrier roll material on a ceiling:

Video about the specifics of laying vapor barrier film:

How to distinguish a vapor barrier material from a waterproofing option:

A vapor barrier constructed in accordance with technological requirements will eliminate premature wear and tear of building structures, eliminate costly heat leaks, and eliminate the possibility of dampness in a country house.

Any processes that take place inside a house or living space affect the strength, durability and integrity of all layers of building structures. For example, due to the destructive effects of moisture, load-bearing wooden elements rot, and the effectiveness of thermal insulation decreases. To protect against moisture coming from external environment and premises, vapor and waterproofing of building structures is performed. We'll talk about insulating the ceiling surface. Moreover, protection from moisture is needed not only when there is a risk of flooding in an apartment building, vapor barrier of the ceiling in a cold attic in private building designed to protect structures and increase the efficiency of insulation.

Why is ceiling vapor barrier done?

The main purpose of the vapor barrier layer is protection against moisture condensing in building structures due to temperature changes. This is usually observed in a private house with an unheated attic. But the vapor barrier of the ceiling in a warm attic is also important, because it protects the insulation from the penetration of moist air from rooms with high humidity.

Second function vapor barrier membranes consists of ventilating the insulation. Compared to a dense waterproofing layer, vapor barrier allows air to circulate in building structures and remove moisture that condenses in the insulation. This protection is especially important when using wooden floor structures.

Vapor barrier functions:

1. Protection wooden elements ceilings from deformation, damage by rot and mold and subsequent destruction.
2. Vapor barrier extends the service life of building structures and insulation.
3. Vapor insulation is part of the insulation system for ceiling surfaces.
4. The fire safety of ceiling structures is increased.
5. If there is a living room above a room with humid processes, then the layer allows you to maintain a favorable microclimate in it.

There are several types of vapor barrier materials, differing in their characteristics and scope of use. What kind of vapor barrier on the attic ceiling will be used depends on the purpose of the room and the presence or absence of heating in the attic space.

Types of vapor barrier materials and areas of application

All vapor barriers according to their operating principle are divided into:

1. Standard materials that are attached to the inside of the ceiling.
2. Also on sale are insulators with a reflective layer that protect against the penetration of water vapor and prevent heat loss by reflecting heat into the room.
3. In buildings for seasonal purposes, vapor barriers with controlled action are used. When the steam cycle is unstable, it is important that the material allows it to escape through the pores in the surface. This insulating material is laid above the insulation (closer to the top of the ceiling). Due to partial vapor permeability, the membrane does not allow moisture to remain in the insulation.
4. There are also insulators with variable vapor permeability. They are mounted above the insulation. Thanks to the special design of the pores, the material allows steam to effectively evaporate from the ceiling and insulation, but at the same time does not allow moisture condensing in an unheated attic to penetrate into building structures.

Also, all insulators are divided according to the type of material from which they are made. The ceiling vapor barrier scheme depends on the insulator used. Let's consider their features in detail.

Glassine

The material is made on the basis of thick cardboard and impregnated with bitumen. It is designed to protect building structures from moisture and water. It is attached to the ceiling on either side. The main advantage is considered to be low price, and the disadvantage is associated with a short service life.

Polypropylene films

The main advantage of polypropylene products is high mechanical strength and resistance to sunlight. The use of these films is justified when the insulating layer is exposed to ultraviolet radiation. This usually happens when there is a significant break in construction during the summer.

Polyethylene films

The film copes well with its tasks when installed in the ceiling between an unheated attic and a bathroom or kitchen. This material has the highest coefficient of resistance to vapor permeation. If the bathroom or kitchen is located under an unheated attic, then it is better to choose a film with a reflective layer.

Advice! To extend the service life of film vapor barrier, buy reinforced two-layer products. Even rodents cannot damage them.

Conventional membranes

Membranes can perform the functions of vapor and water insulators at the same time. Due to one-way permeability, membrane insulators allow steam to escape from the ceiling and prevent moisture from penetrating inside. The pores in the product have a certain configuration - they are narrow at the bottom and wide at the top. For the material to work effectively, it is important to install it right side– the narrow part of the pores is towards the insulation, and the wide part is towards the top of the ceiling.

Important! There are multilayer, single- and double-sided membranes on sale. They are equally effective, but double-sided products are more economical.

Breathable membranes

For efficient work With a regular membrane, it is important to lay it with a ventilation gap of 5 cm between it and the heat-insulating material. Because of this, the thickness of the overlap increases. Breathable membranes do not have this disadvantage. They are mounted close to the insulation. This is due to the peculiarities of their action - they allow water vapor from the heat insulator to pass out, preventing it from becoming damp.

In what cases is ceiling waterproofing used?

The main purpose of the waterproofing layer in the ceiling:

1. Waterproofing the ceiling against leaks from above is important in apartment buildings. It is done in the bathroom and toilet. Its purpose is not only to protect the room from flooding and damage to furniture, but also to prevent the appearance of mold on the ceiling.
2. Coating increases service life finishing materials and protects building structures from damage by water.
3. Waterproofing the ceiling in a private house is designed to protect electrical wiring from getting wet and short circuiting.

Waterproofing of the ceiling surface is carried out in rooms with high humidity (bathrooms, kitchens, bathrooms), in basements, on balconies and loggias, ground floors. In a private house, this layer will protect living quarters in case of a leaking roof.

Waterproofing materials and applications

In apartment buildings, ceilings are often waterproofed from the inside. Materials different in composition, principle of application and action are suitable for these purposes. Each of them is designed for a specific type of surface and has its own pros and cons. The largest selection of products designed to protect against moisture concrete surfaces.

Pasting materials

This insulator is divided into two types:

1. Polymer products are made on the basis of atactic polypropylene and modified copolymers. This includes polyethylene and vinyl plastic.
2. Non-polymer waterproofing materials - roofing felt, roofing felt, fiberglass.

Installation of this waterproofing on the ceiling is quite labor-intensive, so it is not advisable to use these materials. There are adhesive insulators with a self-adhesive base and materials that are fused to the surface using gas burner. The only place where this option for moisture protection is appropriate is a loggia and a glazed balcony.

Penetrating insulation

Penetrating ceiling waterproofing is the most effective method protecting the ceiling surface from moisture. The resulting coating is durable. The mixture is applied to a damp ceiling, which causes the active ingredients to transform into insoluble crystals. They tightly fill all the pores and cracks on the ceiling surface. Suitable for use only on concrete ceilings. It has been proven that these products increase the strength of structures by 15-20 percent.

Important! The main advantage of penetrating waterproofing is its harmlessness and the fact that it does not interfere with air exchange of the treated surface.

Coating waterproofing

These compositions are divided into several types:

• bitumen-rubber (elastic);
• bitumen-polymer (elastic);
• cement-polymer (inelastic).

They are easy to apply and have a reasonable price. However, plaster must be applied above this waterproofing layer. The insulator is laid in several layers and is used to treat cracks, seams, floors, walls, ceilings in bathrooms, bathrooms, balconies or loggias.

Worth knowing! In terms of their composition, coating products can be two- and one-component. The latter are immediately ready for use, while the two-component ones require preliminary preparation.

Waterproofing by plastering

In addition to cement and sand, such plasters contain special additives and waterproof polymers. After hardening, they form a surface that protects against moisture penetration even under significant pressure. Waterproof plasters are suitable for treating brick and concrete surfaces. They are applied only to a dry base, without cracks.

Powder insulation

It is a mixture of resins, plasticizers and cement. A solution of plaster consistency is prepared by diluting it with water. After this, the mixture is simply applied to ceiling surface. This material is rarely used due to its low resistance to mechanical stress.

Painting compositions

This includes special paints, varnishes, emulsions based on rubber, bitumen, latex and other waterproof components. These mixtures are easy to apply, environmentally friendly, and economical in consumption. Their main disadvantage is their short service life. Suitable for different surfaces, including wooden ones.

Water repellents

These are universal ready-made compositions, which are suitable for use on any surface. They have a water-repellent effect. Water repellents are divided according to the method of application. Some are applied by painting, while others are applied like plaster.

The device of the so-called cold attic is used in a significant number of pitched roofs of private residential buildings and baths. This is due to a number of advantages that are provided by such a constructive solution. The main advantage is that, despite the presence of the word “cold” in the name, such an unheated attic can significantly reduce the heat loss of the building.

Description

The installation of a cold attic is the simplest solution from a technological point of view, especially when compared with the alternative warm option or the construction of an attic. The air temperature of such a room, as a rule, is slightly higher (no more than 4 degrees) than the air temperature outside.

The composition of the structure under consideration includes the following elements (from top to bottom):

• roofing;
• external attic walls;
• insulated ceiling between the attic and the living space underneath.

It should be noted that insulation of the ceiling of a cold attic with mineral wool or other heat-insulating material can be done both from above and below from the side of the living room, regardless of whether it is wooden or concrete.

The option under consideration has a number of advantages:

• reliability of waterproofing of the coating. It is achieved by reducing the number of superstructures protruding above the roof, which, as a rule, are its weakest points;
• ease of operation. The existing internal under-roof space makes it easy to inspect and maintain all floor and roof structures;
• the overlap area is smaller than the area of ​​the pitched roof, which reduces the area of ​​possible heat loss;
• availability of additional operational premises.

In order for the benefits of a cold attic design to be fully realized, it is necessary to correctly and competently resolve several issues related to the insulation of the attic floor, as well as proper ventilation of the cold attic.

Organization of ventilation

The main purpose of ventilation in this case is as follows:

• removal of excess water vapor penetrating through the ceiling from below from the residential part of the building, in order to prevent the appearance of condensation and moistening of the insulation and roof truss system;
• creating an optimal microclimate.
• Ventilation occurs through two types of vents:
• cornices (the air passing through them is called supply air);
• ridge (exhaust air passes through them).

Their total area should be 0.2-0.33% of the roof covering area, in other words for a covering area of ​​1000 sq.m. The area of ​​the vents should vary from 2 to 3.33 sq.m. This calculation is carried out in accordance with SNiP standards, and it is quite simple to do. It applies equally to various options for roofing pie covered with metal tiles, corrugated sheets or soft tiles.

The basic rule for the location of vents is as follows: the ventilation system operates most efficiently when the inlet and outlet openings are as far apart as possible.

In most cases, a scheme is used with an approximately uniform arrangement of vents around the perimeter of the building under the overhangs and along the entire length of the roof ridge.

Additional ventilation is often performed through dormer windows installed on the gables or roof slopes, which help with enhanced ventilation. When installing them, they are guided by the rule of symmetry: in order to prevent the presence of unventilated areas, dormer windows should be located on opposite slopes.

Typically, dormer windows are made of three types:

• rectangular;
• triangular;
• semicircular.

They are installed in such a way that the lower part of the window is no more than 1 meter from the floor level, and the upper part is at least 1.75 meters higher from the floor level. Often, dormer windows are used as an exit to the roof for the purpose of inspecting the roof and the elements of the ventilation system and chimneys installed on it. Sometimes a special hatch is installed for this purpose.

In order to prevent birds from entering, the vents are equipped with protective nets or gratings, and blinds are installed on the dormer windows.

Thermal insulation options

The cold attic design can be used in buildings of any number of floors. One of the prerequisites for its normal operation is high-quality insulation of the floor. It is performed in one of two ways:

• from the attic side;
• from the inside from the residential part of the building.

Thermal insulation from the attic

This option is considered the most effective. A wide variety of ceiling insulation for a cold attic can be used: mineral wool (the most commonly used option), polystyrene foam, expanded clay, etc.

Sequence of work stages:

• vapor barrier device (ordinary PVC film or modern materials with much higher performance characteristics can act as a vapor barrier material);
• laying mineral wool thermal insulation in two layers;
• creation of a protective coating from cement bonded particle boards.

This unit is one of many possible ones that fulfill the basic requirements for insulating the ceiling of a cold attic and allow you to obtain the following advantages:

• due to the presence of a vapor barrier, moisture does not enter the insulation;
• the DSP coating allows you to move freely without damaging the insulation;
• the design is quite reliable and durable (to further increase the service life, it is recommended to treat the surface of the DSP with antiseptics, which significantly reduce the likelihood of fungi or mold appearing).

It is imperative to additionally insulate the perimeter of the attic. It is carried out by laying a layer of mineral wool 0.75-1 meter wide and a layer thickness of 10 cm. This will reduce or completely avoid the risk of freezing in the upper floor rooms in the corners.

Thermal insulation from inside the living room

Installing a ceiling in a private house with a cold attic and insulation from the inside is done much less frequently, since the work is accompanied by a number of disadvantages:

• the ceiling level decreases;
• Carrying out thermal insulation work disrupts the finishing, if it has already been completed, and requires subsequent repairs;
• not all thermal insulation materials are useful and environmentally friendly, which leads either to an increase in the cost of work or to a decrease in living comfort. For this reason, the use of mineral wool is not recommended. In addition, it is always recommended to leave a ventilation gap between the thermal insulation material and the finishing material.

Thermal insulation from the inside is often carried out in parallel with the installation of suspended ceilings.

One of the most common methods of insulation from the inside is the option using extruded polystyrene foam (penoplex):

• First, the sheathing is installed, onto which the drywall will subsequently be attached. The thickness of the sheathing beam should be 2-3 mm greater than the thickness of the insulation, and the sheathing pitch should be 1-2 mm less than the width of the penoplex;
• after this, the insulation is secured between the sheathing bars with additional fastening with dowels to the ceiling;
• plasterboard or suspended ceiling is attached as the final finishing of the suspended ceiling.

There are many other possible ways to insulate a ceiling, but despite all the differences in the technologies and materials used, the basic principles must correspond to those given above.

Conclusion

The installation of a cold attic, if the work is carried out competently and the technology requirements are met, is an effective and expedient design solution.

Vapor barrier of the attic floor of a cold attic protects wooden floor structures and insulation from steam entering them from the premises of the house. Steam condensing on beams can contribute to wood damage by fungi and mold, thereby reducing the service life of the structure. Condensing in the thickness of the insulation increases heat loss in the house, because Water itself is a good conductor of heat. In addition, water, freezing in the thickness of the insulation during the cold season, destroys the polymer bonds of the fibers and reduces the service life of the material.

Vapor barrier for a cold attic, when using foil materials, in addition to its main function, it allows you to reduce heat loss and, accordingly, heating costs due to the creation of a heat-reflecting screen.

Attic vapor barrier materials There are 2 main types on the market:

1. Film vapor barrier- does not allow steam to pass through (vapor barrier only).
2. Foil vapor barrier— does not allow steam to pass through and reflects thermal radiation (steam and heat insulation). This vapor barrier is installed with the foil side facing the premises.

Vapor barrier of attic floors with foil materials due to its characteristics, it is most preferable when building a reliable and heat-efficient house made of aerated concrete, brick or monolith.

Vapor barrier for the attic “pie”:

1. Attic floor (ladders) - necessary for maintenance, repair of the roof and attic space. In order to get into the attic, provide attic staircase with insulated hatch (Thermo). To exit from the attic to the roof, we recommend installing blind or glazed exit hatches (Velux, Vilpe, etc.) on the roof.
2. Para- or super-diffusion moisture-proof membrane - for effective removal of steam from insulation.
3. Insulation - mineral wool slabs. Recommended thickness for the Moscow and Leningrad region is 300mm. 200 mm are laid in the space between the beams, the remaining 100 mm are laid perpendicular to the laid layers - counter-insulation. For comparison, building codes in Finland determine the thickness of insulation from 400 to 500 mm. It is recommended to delay the installation of insulation as much as possible - no earlier than 6 months after the completion of the construction of the house frame. Because For the construction of floors, timber is mainly used natural humidity. The timber must dry thoroughly, otherwise there is a high probability of damage to the wood by fungi and mold, which entails additional expenses for dismantling/installation work and treating wood with bleaches and antiseptics.
4. Counter grille and ventilated gap. For effective ventilation and removing steam from the surface of the moisture-proof membrane.
5. Floor beams. As a rule, in private housing construction a 50x200mm board or 100x200mm natural moisture timber is used.
6. Lathing is the basis for laying insulation. It is recommended to use a 100x20 (25) mm board as lathing and lay it in increments of 70-80 mm. The resulting cracks will form an additional air thermal layer under the insulation. That. insulation slabs (mats) will not lie on vapor barrier film, but on a rigid base, under which there will be a vapor barrier. This solution eliminates the possibility of accidental damage to the vapor barrier or its pushing through when laying insulation, during maintenance and repair work of the roof and attic. In this case, you can begin interior decoration of the premises, and postpone the installation of insulation as much as possible (see above).
7. Vapor barrier of attic floor on wooden beams- is attached using a construction stapler from below to the rough ceiling (sheathing), which allows you to cut off vapors from the entire floor structure. It is necessary to overlap the vapor barrier rolls by at least 15-20 cm and carefully glue them with aluminum adhesive tape. It is necessary to form overlaps on the walls of 15-20 cm and carefully glue them (place them under plaster and other wall finishing). Carefully seal the passages through the attic ceiling of chimneys, ventilation pipes and other utilities using special hoses. The best material as a vapor barrier is polyethylene film high density from 200g/m² and above.
8. Closing attic - the finished ceiling is attached to the vapor barrier. The finished ceiling (OSB, gypsum board, etc.) is installed along the sheathing and guides. For the best fire protection It is recommended to “sew up” the ceiling with 2 layers of plasterboard sheets.

Vapor barrier for cold attic floors (diagram):

Professional opinion: most effective attic floor insulation vapor barrier for the Moscow and Leningrad regions - this is insulation of the attic with mineral slabs 300 mm thick with foil vapor barrier.