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How to insulate a wooden ceiling in a private house. How to properly insulate the ceiling and walls in a private house. Materials required for installation

Insulation of the ceiling and walls is an important component of home improvement. Every owner of a private home faces this question. Most of heat escapes through the ceiling, so insulating it is very important. Modern market building materials today there is a large selection of different insulation materials. But, first of all, you need to decide how to carry out thermal insulation.

There are two methods, indoors or outdoors. Both bring good results. You should choose the one that is more convenient in a particular situation. If we talk about differences, they differ in technology and materials.

Selecting a thermal insulator

To insulate the ceiling in a private home, it is important which material to choose. Vapor-permeable heat insulator produce insulation from the inside. Vapor-tight insulation is perfect for working outside.

When purchasing material for insulation, you need to pay attention to the following qualities:

• Environmental friendliness and safety;
• Flexibility, the ability of insulation to restore its shape;
• Susceptibility to external influences or compressive strength;
• The density or weight of the insulation allows you to calculate the load on the attic floor;
• Fire resistance. There are 4 flammability classes in total, the least flammable materials are class G1.

One more nuance when choosing insulation. It is worth considering what the floors in the house are made of. Almost any insulation material is suitable for wood with planks. But for concrete slabs mainly used heavy bulk materials or slabs with good density. Thick thermal insulators in rolls and mats are also suitable. All this is important to know before you start insulating the ceiling.

How to insulate a ceiling in a private house

What insulation is better for the ceiling? It depends on many factors. Their choice today is wide. It is worth dwelling on their qualities in more detail.

Expanded clay is a lightweight bulk material. It is made from special clay. As a result of processing, porous granules are obtained. Suitable for external insulation. He non-flammable, retains heat well and does not absorb moisture. It also does not harbor rodents. Therefore, when the question arises of how to insulate the ceiling in a private house, many prefer expanded clay.

Fiberglass-based insulation is light in weight. They have all the properties necessary for thermal insulation. But they need a special coating that repels moisture. They are less resistant to its effects than others.

Mineral wool is not flammable, but its moisture resistance is average. This is fiber insulation. Available in rolls or slabs. It has good thermal insulation qualities. In addition, it has excellent wear resistance. Suitable for insulating the ceiling in a private house from the inside. Its advantages also include:

However, mineral wool can cake and lose its properties. Glass wool is also classified as fiber insulation. It is quite strong and elastic, but is subject to shrinkage.

Such modern heat insulators as polyurethane foam, polystyrene foam, penofol are not inferior traditional materials. They are made from foamed polymer. They can be produced with foil. This is additional protection against water. Foil also increases the thermal insulation qualities of the material. When insulating the ceiling, the material may be good choice.

Insulation materials made from extruded polystyrene foam are also lightweight and have low thermal conductivity. They have good mechanical strength and affordable. They can warm the attic, which is planned to be used. Disadvantages include low vapor permeability. Therefore, when using them, you will have to take care of ventilation. They are not suitable for ceilings with complex configurations.

Penoizol is another one polymer material. It is durable. Has virtually no limited period operation.

Polystyrene foam is fireproof, weighs little and does not place a large load on the floors. Good thermal insulator. It does not absorb moisture, but does not allow air to pass through. Additional ventilation will be required. Available in slab form. It keeps its shape well. It can be combined with mineral wool.

This combination for ceiling insulation has its pros and cons. The properties of both insulation materials prevent warm air from escaping outside. However, the disadvantages include low level fire safety polystyrene foam and the fact that rodents can live in it.

There are natural cork insulation. These materials are made from compressed cork chips and resin. They allow air to pass through well, but are flammable.

Ecowool is considered harmless to health and has low thermal conductivity. It is made from cellulose. To reduce flammability she's being processed boric acid or fire retardants. When using it, a layer of waterproofing is not needed, because ecowool absorbs moisture. Suitable for all types of floors.

How to insulate ceilings in a private house from the outside

In a private house, insulation of the ceiling from the outside, that is, from the attic side, is done by laying a heat insulator on the ceiling or in its voids. This eliminates the need to disassemble the ceiling and do the repairs again. Maybe, best option for a new or recently renovated home.

How to insulate ceilings from the outside, insulating the ceiling with sheets of polystyrene foam or polystyrene. It is better to choose thick foam, about 40 mm.

First, the attic must be cleared of debris. Then measurements are taken. Sheets of insulation are laid on the floor of the attic. They are fastened together polyurethane foam. If you plan to use the room as an attic, for example, then you need concrete screed. A reinforcing mesh made of metal is placed on the insulation, and the screed solution is already poured onto it.

Insulation with mineral wool

Mineral wool is also used for external insulation. After all necessary measurements floor joists are installed. Then layer vapor barrier material . You can also use glassine. The insulation is laid loosely, but without gaps between the joists. The next stage is flooring.

For outdoor insulation is suitable and expanded clay. If the floors are made of concrete, then the insulation process comes down to the following:

• A layer of waterproofing is laid on the slabs. Expanded clay is poured on top. The layer should be about 10 cm;
• Reinforcing mesh is laid on it. Plywood is laid on top as protection;
• Next, a screed is poured onto the reinforcing mesh;
• When the screed is completely dry, you can install the finishing coating.

It is important to take expanded clay of different fractions. This will prevent the insulation from shrinking.

Expanded clay insulation in a wooden house is done along the space between the beams. A layer of waterproofing is placed between the load-bearing beams. Typically, it is made of polyethylene. It needs to be secured. In between Expanded clay is poured between the beams. It is lightly compacted. Fiberboard is placed on top of it. Now it's time for the finishing coat.

To work with polystyrene foam you also need a vapor barrier. Foam boards are laid tightly. It is important here that the heat insulator elements are hermetically connected at the joints. For this purpose, polyurethane foam is used.

Combined option insulation with polystyrene foam and expanded clay gives good results. Polystyrene foam is placed underneath, and the slabs are covered with expanded clay on top. I combine polystyrene foam with mineral wool. In this case, it is placed on foam boards.

A very old and proven method is insulating the attic with sawdust. But they are flammable. Therefore, they are often mixed with cement.

Penoplex modern insulation. Durable and quite suitable for insulating concrete floors in a private house. First, the surface of the ceiling is leveled and a layer of vapor barrier is laid. Penoplex is attached to the surface with dowels. The joints are sealed with polyurethane foam.

Insulation from the inside

Internal ceiling insulation in a private house is usually carried out with mineral heat insulators. For example, basalt wool. From the inside, the insulation is hidden behind suspended plasterboard ceilings.

1. First, a metal frame is attached to the ceiling;
2. Insulation is glued between the profiles;
3. Sheets of plasterboard are sewn onto the frame. Then the final finishing of the ceiling is done.

If mineral wool is chosen as insulation, then it is better to use tile adhesive. Mineral wool cannot be compressed; this causes it to lose its properties. When insulating with mineral wool in a suspended ceiling, a vapor barrier is not needed. This can lead to fungus.

The ceiling is insulated from the inside of the house using polystyrene foam. It is important to consider the density of the material here. For internal insulation Density 15 kg/sq. is suitable. m. or 25 kg/sq. m. Sheets of foam plastic are attached to the ceiling with glue. They can be coated with plaster.

We insulate the walls from the inside

It is also important to insulate walls in a private house. In principle, the heat insulators used are almost the same as for the ceiling.

• Foiled polyethylene foam;
• Polyplex;
• Mineral wool;
• Expanded polystyrene;
• Polyurethane foam.

Polyurethane foam is considered the most environmentally friendly thermal insulator. Therefore, quite often they insulate walls from the inside. But it is not suitable for do-it-yourself insulation. This requires special equipment.

Basalt wool and fiberglass are also used.

Wall insulation technology

In addition to insulation, you will also need materials such as timber. If you plan to use mineral wool. Necessary and slats for fastening material. Can be used as a vapor barrier plastic film or membrane. We also need material for finishing the walls.

The walls must be dry before work. It wouldn't hurt to treat with an antiseptic to avoid fungus.

Insulation with mineral wool requires the presence of a frame. Its elements are installed vertically. Insulation boards fit tightly, leaving no gaps. You can secure them with special dowels to the surface. A waterproofing material is stretched over the insulation. It can be taped at the joints. Next comes already fine finishing walls

Expanded polystyrene requires leveling of the working surface. After priming, it is treated with an antiseptic. When the walls are dry, you can install insulation. It is installed frameless and secured with glue. They insulate with polystyrene foam in the same way. After the heat insulator is glued, small seams are sealed with foam. Wider cracks are insulated with strips of material. Then the finishing coat is applied.

Insulation is very important not only for saving energy resources. This procedure will make your home comfortable and cozy.

For those who consider ceiling insulation to be cold roof and optional, it is worth remembering condensation and significant heat loss in winter period. Drops of condensation that form on the ceiling and inclined surfaces due to temperature changes fall down the collar and head - a very unpleasant sensation at any time of the year.

Warm air rises upward according to the law of convection - for further circulation. When it receives significant cooling from a cold ceiling, heating the room can be considered ineffective.

That is why any method of insulating the roof, ceiling and attic space is considered the most effective measure of heat conservation.

How to insulate the ceilings and attics of private houses?

When building private houses, everyone wants to save money. But no one will dispute that cheap building materials are not effective or have a limited service life. It is better to master installation technology, where available, in order to save on installing insulation yourself.

Attention: The more technologically each stage of construction is carried out from high-quality materials, the longer the house will last without requiring major renovation. This is the essence of saving for the future.

Any construction supermarket will offer a complete list of insulation materials that are used during the construction of a roof or after completion of rough work.

They are available in different forms:

• rolled materials;
• porous briquettes;
• sheet insulation;
• sprayed two-component mixtures;
• bulk materials;
• fiber insulation;
• foil wrapper.

The choice of insulation for the ceiling of a particular building depends on the type of surface and temperature conditions in the interior.

In this case, we are talking mainly about external insulation - the floors of the attic or attic (on the other side of the ceiling of living rooms in residential buildings). For example, they use materials that are not suitable for energy saving methods in a bathhouse where there is a high level of humidity, and vice versa.

In some cases it is necessary to use special equipment. You can’t do without it when spraying with polyurethane foam.

But this method is indispensable when it comes to processing inclined and negative surfaces, metal frame and a combination of materials of different textures used when installing roofs of complex shapes.

It is much easier to insulate the joists with sawdust or expanded clay (of any fraction). They belong to bulk materials that do not require complex installation.

Apart from leveling, nothing needs to be done with them; then the substrate and cladding are laid, if this is a residential attic. For an empty attic, you can leave bulk materials without any fastening.

Tip: In some areas bulk insulation materials are free. In coastal areas, this is dry seaweed that a storm throws onto the coast. In the area of ​​the sawmill and wood processing enterprises there is a lot of sawdust, shavings and crushed bark.

Internal insulation of the attic along the beams and rafters - laying mineral wool with large briquettes, but the floors (the reverse side of the ceilings) must be insulated.

Specifics of a cold roof and its insulation

Relying on modern technologies, any roof is erected like a multi-layer sandwich or sandwich, hence the borrowed name. Hydro- and vapor barrier, thermal insulation and multi-layer roofing are expected.

It is necessary to treat building materials with fungicides (from fungi), antiseptics and chemicals to prevent mice from getting into the attic. Rodents easily climb stairs and any inclined or porous surface.

Cold roofing is a dubious economy, but it is appropriate in different cases:

• For country houses, which are not used in winter;
• for auxiliary buildings;
• with high-quality insulation of the ceiling in the house (outside and from the attic);
• when the foundation is on unstable soils, it cannot be subjected to a large load in the form of several floors and an insulated roof of an intricate configuration;
• if the attic or attic is not used for living rooms, and the house is warm enough, built using energy-saving technology, and also in the form of a log house (made of natural wood).

In these cases, it is necessary to insulate the ceiling in a house under a cold roof.

At the same time, all communications, chimneys and heating pipes passing through the attic are insulated with rolled, foil and sprayed materials.

The advantages of such insulation:

• Comfortable microclimate all year round.
• Minimum temperature difference.
• Additional sound insulation from the roof (rain, hail, gusty winds).
• Prevents the formation of condensation.
• Energy saving.

If possible, the overlap between the top floor and a non-residential cold-type attic should be done on both sides.

You can use suspended and suspended ceilings, multilayer structures made of gypsum plasterboard, behind which it is easy to hide wires and communications. A good example is in the photo of ceiling insulation.

Tip: If possible, use non-flammable materials or non-flammable to reduce the likelihood of fire to a minimum.

Common insulation materials

Please note that high-quality insulation can only be complex - windows and doors, external and internal surfaces.

Spray polyurethane foam

To work with your own hands you need to rent special installation for mixing a two-component composition, which is supplied through a sprayer with nozzles in the form of “snow flakes”.

They stick well to any surface, even those not treated with expensive primers. The advantage is that the tube feeds everything hard to reach places in the attics.

Expanded clay

Bulk material in the form of small pebbles based on clay, which is scattered throughout horizontal surface attic.

Cellulose ecowool

It resembles flakes, which are also sprinkled over the surface without any fixation.

Foam sheets and rolls

A popular material, since foam insulation is one of the most affordable means. It can be placed in specially prepared cells or stitched layer by layer over the entire surface.

Mineral or stone wool

Practical non-flammable fibrous porous material that does not harbor mice and insects. Produced in sheets, briquettes and rolls.

Today, insulation with mineral or basalt wool remains the most popular due to the properties of the material and convenient packaging.

Wood waste

Available insulation. Although wood is a combustible material, it will not ignite without oxygen supply and preheating. But to guarantee, additional treatment with a fire-fighting mixture is recommended.

Disadvantage - you can introduce wood pests that can cause damage to wooden roofing.

As natural insulation materials There is waste in every area Agriculture or vegetable waste, suitable for these purposes. These are cake and husks, hay and straw, crushed reeds and corn, fallen leaves and pine needles.

They can be mixed, used separately, if there is no other alternative, poured over expanded clay. A layer of 5-7 cm is enough for the heat retention to be noticeable.

To reduce the likelihood of ignition, it is better to mix plant waste with clay or sprinkle sand on top. Plant mixtures are susceptible to rotting, so over time you will have to change old layer for new insulation.

The wires being laid need additional insulation, so they are usually enclosed in hollow corrugated tubes from non-flammable polymers. Keep in mind that each heat-insulating material has its own installation method and service life.

Photo of ceiling insulation

Insulating the ceiling in a private house with a cold roof ensures a comfortable microclimate in the building throughout the year. It is carried out from the attic or living quarters using mineral wool, sawdust, polyurethane foam, expanded clay, polystyrene foam and other materials.

Proper insulation of the ceiling makes it possible to retain 25–40% of the heat lost through the roof. This saves a lot of money spent on electric, gas and other types of heating.

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Warm and cold roofs - design features

High-quality insulation of the roof of a private house is an important task. Experts recommend solving this problem at the construction stage. Properly designed and executed thermal protection has the following properties:

• protects the building from damage;
• reduces heat loss;
• forms optimal temperature indicators in the premises of the home.

Individual housing constructions are covered with warm and cold roofs. There are significant differences between them.

The former refers to structures with slopes that are completely protected from frost by a cake of successive layers of moisture-, heat-insulating and roofing materials. They are built in cases where the attic (attic) is used as a living space.

Warm roofs cover buildings that are used throughout the year. The cost of constructing such structures is high. Therefore, many owners of private houses and summer cottages install cold roofs. The costs of their installation are significantly lower.

An uninsulated roof is made of wood truss structure with waterproofing laid on it and roofing covering. Such systems are recommended for houses with unheated attic space, private garages and bathhouses.

In order to create a comfortable temperature regime and reduce the cost of heating homes with a cold roof, the ceiling located under it is insulated. The effectiveness of this measure is high, since heated air, according to the laws of physics, always moves upward.

Thermal insulation options – which one to choose?

Protection of the ceiling surface from the cold, if necessary, is carried out in the house in use. There are two ways to perform this procedure:

• From the outside (attic side).
• From inside the room.

The first method is considered more effective by experts. This is due to the fact that the ceiling in a private house is in most cases made of wood, which is an excellent thermal protector.

When insulating from the outside, backfill and slab materials. The selected insulator is mounted on the ceiling, after which it is covered with a subfloor.

Protection from the inside is carried out when there is no access to the attic, and during the reconstruction of old houses with ready-made attic structures. In such cases, the following installations are carried out sequentially on the ceiling:

• lathing (frame) made of wooden or metal elements;
• insulation;
• sheathing made of plasterboard sheets (GKL).

The disadvantages of the technique are a noticeable reduction in the height of the room, the labor intensity and complexity of the operation, and insufficient efficiency. Therefore, thermal insulation from the inside is rarely carried out.




Important point! Any type of insulation in houses with cold roofs should be carried out comprehensively, that is, protect not only the ceiling, but also windows, doors, and floors.

Types of heat insulators and requirements for them

Various materials are used for thermal protection of ceilings. They must have the following properties:

• Sufficient moisture resistance.
• Resistant to fire.
• Low thermal conductivity.
• Environmentally friendly.
• Light weight.
• Durability.

Home craftsmen most often perform ceiling insulation using sawdust and other natural materials, mineral wool, expanded clay, ecowool, polystyrene foam and extruded polystyrene foam, penoizol and polyurethane foam. Thermal insulation concrete surfaces It is recommended to do:

• filling products;
• dense mats and slabs.

For wooden floors, it is better to use rolled and bulk materials.

Old-fashioned methods are still used today

Some home craftsmen insulate ceiling surfaces with natural materials - clay, sawdust, reeds, algae, hay, pine needles, straw, old leaves. They are easy to assemble yourself or purchase with minimal financial investment.




Such gifts of nature are characterized by low mass and low thermal conductivity. Their disadvantages are flammability and tendency to rot. The latter feature necessitates regular replacement of such thermal insulation.

Most Popular natural materials for thermal insulation - sawdust and shavings. They are laid in the attic using a simple method. She demands preliminary calculation thickness of the protective layer, depending on climatic winter conditions, marked in the area where the house stands.

The described insulation materials can be easily installed with your own hands on wooden ceilings from the attic side. The work flow is simple:

• The ceiling is coated with clay diluted in water. The applied layer is made of small thickness. Then the coating will not crack after drying.
• A little sand is poured on top, which is evenly distributed over the treated base.
• A layer is made from a composition that includes slaked lime and urea (proportions 1 to 1). It eliminates the risk of damage thermal insulation material rodents.
• Sawdust is poured in. It is advisable to cover them with waste slag, which reduces the risk of fire.

If the under-roof space is planned to be used for any work, boards are laid on top of the thermal insulation cake.

They will allow you to move comfortably around the attic. There is a second method of insulation using shavings or sawdust. Ceiling surface covered with a waterproof film. Natural material

mixed with cement and water in a ratio of 10:2:1.5. The resulting composition is laid out on the floor (layer height – 20–25 cm).

The created insulation will take 3–4 months to dry. Therefore, it is advisable to carry out such work in the spring.

Reliable floor protection is another inexpensive way In demand building material is clay. In its pure form, using it to insulate the ceiling is problematic (it is necessary to construct a layer 0.7–0.8 m thick). But when sawdust is added to it, a fairly effective heat-insulating composition is obtained.

• The mixture is prepared as follows:
• Plain water is poured into an old, capacious barrel.
• Pour 4-5 full buckets of clay into the container.
• Mix the components thoroughly.



Part of the composition is poured into a concrete mixer, sawdust is added to it and the unit is turned on. Mixing is carried out until a solution of medium consistency is obtained. It is used to pour the ceiling (between the beams), on which it is previously laid.




When the solution dries completely, cracks may form on it. They must be covered with thick clay.

The most popular insulation - types and features

Mineral wool is considered the most popular material for protecting floors from frost in houses with cold roofs. It is mounted on the side of the room or in the attic, and is made from various raw materials:

• molten glass and sand;
• metallurgical slags;
• rocks.

Glass wool having a water absorption rate of 0.6–0.8 kg/sq. m., available in the form of mats and rolls. Their installation is carried out strictly from the attic side.




It is not recommended to use slag for insulating residential buildings. Its environmental friendliness leaves much to be desired. When wet, it releases acidic compounds that destroy structural elements Houses.




Basalt material is optimal for thermal insulation of ceilings outside and inside. This mineral wool has high plasticity and minimal fragility. It is manufactured in the form of plates and rolls.




Many manufacturers offer basalt products with an additional foil layer. It reflects heat into living room, which enhances the thermal insulation capabilities of the material.

Important nuance! Any type of mineral wool contains phenol-formaldehyde compounds (playing the role of a binding element), which are potentially unsafe for human health. This is the biggest disadvantage of the described heat insulators.

The procedure for installing mineral wool from the attic side

Insulation is carried out using roll or slab products. The former are best used when the floors in the house are wooden, the latter - if the ceilings are concrete.

Laying rolled mineral wool is an elementary process. The work flow diagram is given below:

• The space between the beams is covered with a vapor barrier film. It is mounted overlapping with an overlap (15–25 cm) on vertical surfaces. The joints are sealed with tape.
• A layer of mineral wool is laid on top (its thickness is calculated in advance). The cut pieces should fit tightly into the spaces between the beams.
• The insulation is covered with a waterproofing membrane.
• A boardwalk is being constructed.


Before using mineral wool, concrete floors are carefully leveled and covered with a moisture-proof film. The slabs are installed on top of it. The latter are laid staggered. The finished structure is covered with boards or plywood sheets.

Eco-friendly insulation – what and how is it done?

Expanded clay is made from natural clay, which makes it an absolutely clean and safe material for thermal insulation of ceilings. It also has a lot of other advantages:

• non-flammability and increased heat resistance;
• hypoallergenic;
• chemical inertness;
• long service life without loss of initial properties.


Based on the size of the granules, expanded clay is divided into three types. Small fractions of the material provide the densest layer of thermal insulation.

Only concrete ceilings can be insulated with expanded clay. Wooden bases cannot withstand its heavy weight. The layout of the material from the attic space is as follows:

• The ceiling is cleaned and covered with a vapor barrier film. The latter is mounted with an overlap of 40–50 cm on vertical surfaces and overlapping individual pieces on each other. The joints between the parts of the membrane are fixed with masking tape.
• Knead natural clay in a suitable container. Distribute it in an even layer over the film.
• Cover the prepared base with expanded clay (height depends on winter temperatures in the region and equals 15–50 cm).
• Prepare a thick solution from 3 parts sand and 1 cement. Fill the insulated surface with a layer 5 cm thick.

The work is completed. There is no need to make flooring over expanded clay. The cement-sand screed is solid and reliable. It can easily withstand the weight of massive objects and structures, people, and heating boilers.

Ecowool – laying technologies

Natural cellulose insulation is not widely used in the CIS, despite the fact that it is 100% environmentally friendly. This material has a number of advantages:

• Light weight. Ecowool can be laid in a layer of any height without worrying that the ceiling will collapse under its weight.
• There is no danger of mold formation and the development of microorganisms under the insulation.
• The thermal insulation layer is characterized by complete tightness due to the absence of seams.
• Non-flammability and ability of cellulose to self-extinguish in case of fire.
• Long service life.



Ecowool is installed using dry or wet methods. The first involves scattering the insulation between the beams, its uniform distribution and compaction. There is no need to lay a waterproof film under cellulose material, since it is classified as a natural absorbent.

Wet technology is implemented using special equipment. It mixes the adhesive mass with cotton wool and sprays this composition under a certain pressure.




The heat insulator penetrates into all gaps, forming a solid protective layer containing air ions inside. The recommended insulation height is 25–50 cm. Complete hardening of the coating is observed after 10–14 days.

Plastic polymers - easy to install and affordable

Polystyrene foam and its variety - extruded polystyrene foam (penoplex, EPPS) have been used for insulating ceilings for a long time. The advantages of these materials:

• low thermal conductivity;
• low bioactivity;
• large selection of thicknesses and geometric sizes;
• reasonable cost;
• minimal water absorption.



Foam plastic and EPS also have many disadvantages. Firstly, they are flammable. In the event of a fire, such products support the combustion process and actively release compounds that are unsuitable for breathing.

Secondly, the materials in question are destroyed by sunlight. Thirdly, they are characterized by low chemical resistance.

Expanded polystyrene boards do not allow air to pass through. Therefore, it is advisable to mount them only on concrete floors. When installed on wooden structures, moisture will begin to accumulate under the insulation, which will lead to mold.

It is not difficult to correctly install penoplex and its analogues with your own hands. The work algorithm is as follows:

• The ceiling base in the attic is leveled (the protrusions are knocked down, the recesses are filled with putty). If necessary (height differences of more than 2 cm), a cement screed is made.
• A vapor barrier film is laid.
• Insulation boards are laid. They are mounted staggered, moving each other as closely as possible.
• The products are fastened with dowels with a large head. They are buried 6–9 cm into the material. The top of the hardware must be recessed into the slabs by 1.5–2 mm.



The joints between the elements of the thermal coating are blown with polyurethane foam. After the latter has hardened, the insulation is filled with a cement-sand reinforced mixture.

Sprayable compositions - advantages and disadvantages

Liquid thermal insulator polyurethane foam (PPU) is supplied to the surfaces to be treated using special equipment. It can be applied in several layers, which makes it possible to insulate ceilings in houses located in cold climatic regions. Other advantages of the material:

• penetrates into the smallest pores and crevices, hard-to-reach places;
• non-flammability;
• suitable for wooden and concrete floors;
• invulnerability to microorganisms and rodents;
• minimal water absorption (0.1–0.2% of volume) and thermal conductivity (0.027 W/mK);
• absence of cold bridges;
• excellent sound insulation;
• resistance to temperature fluctuations.

When spraying polyurethane foam, there is no need to lay vapor and waterproof films. It guarantees a durable, seamless surface that you can walk on.




If home handyman There is no special equipment that supplies polyurethane foam to the base under a given pressure, insulation becomes impossible. Another disadvantage of polyurethane foam is its complete vapor permeability. This feature of the material negatively affects the microclimate in the home.

Installation of thermal insulation on the room side - preparation of surfaces

On wooden floors apply a primer with antiseptic properties and a fire retardant effect. Processing is carried out as carefully as possible. The brush needs to be deepened into the gaps between the ceiling elements, filling them with a protective composition.

The second stage of preparation is sealing cracks and small gaps in the ceiling. The operation is carried out using polyurethane foam or putty on wood. After hardening, excess mixtures used are removed with a sharp knife.

Concrete ceilings are treated a little differently. The event schedule is as follows:

• The existing decorative coating is dismantled, the peeling plaster is cleaned off.
• Cracks in the foundation are expanding. Remove dirt and dust from them with a soft brush and prime them.
• Small defects are filled with sealant or putty.



Adhesive Concrete Contact is applied to the prepared surface. It enhances the adhesion of the ceiling and the insulation used. The insulator is installed after the soil has completely dried.

If insulation materials It is planned to sheathe it with clapboard or plasterboard; it is necessary to construct a sheathing on the ceiling. The surface is marked using a level (regular, laser). Smooth straight lines are marked on it, serving as a guide for installing metal or wooden guides. The distance between the latter is equal to the width:

• insulation plus 4 cm if mineral wool is used;
• expanded polystyrene boards, ordinary polystyrene foam and other solid materials.

A frame structure made of wood is attached to the ceiling with self-tapping screws or dowels in increments of 50–60 cm, and made of metal with special hangers. After constructing the sheathing, they begin laying thermal insulation, which is then covered with a vapor barrier membrane.




The film is fixed with double-sided tape (on steel profiles), staples and a stapler (on wooden blocks). The created pie is covered with clapboard, plasterboard sheets. The joints between the latter are reinforced using serpyanka, and then they are puttied with gypsum compound. It is also used to mask holes from the heads of fasteners (screws).

If the insulation will not be removed, it can be glued to the base ceiling liquid nails, polyurethane foam or cement-based compositions. The algorithm for performing the work is given below:

• The selected glue is applied pointwise with a spatula or trowel onto reverse side thermal insulation boards.
• The product is pressed against the ceiling, wait 10–20 seconds.
• The installed insulation is additionally secured with mushrooms and spacer plastic nails.



The gaps formed between the laid and fixed slabs are blown in with foam. Its excess is cut off with a knife. It is recommended to cover products made of foam plastic and EPS with serpyanka and treat them with plaster.

Most people try to insulate the walls of a private home as best as possible to avoid heat loss. In fact, 60% of thermal energy escapes through the ceiling because warm air tends to rise up and goes out through the ceilings. In addition, there is always a high level of humidity in the ceiling area, hence mold and mildew in the corners. An insulated ceiling will not only make the house more comfortable, but also protect property from damage.

Methods for insulating the ceiling

In a private house, insulating the ceiling becomes task No. 1. To insulate the ceiling and reduce heat loss, you can use the following methods:

• Insulation of the ceiling from the inside. This is the case if there is a not an attic, but an attic. A frame is constructed from wooden beams, which is attached to the ceiling using a hammer drill and dowel nails. Inside the frame is filled various insulation materials, and a vapor barrier is placed between the ceiling and the insulation. Then the insulated ceiling is covered with plasterboard. The disadvantage of this method is the “hiding” of a significant part of the ceiling, as well as the complexity of the work.
• Insulating the ceiling from the outside. This method good if there is an attic under the roof. There are also variations depending on the type of insulation.

Foam insulation

Before you begin the insulation process, you need to empty the attic of excess rubbish, sweep out all the garbage, and carry out wet cleaning down to pure concrete. Depending on the size of the area to be insulated, it is necessary to purchase the appropriate amount of polystyrene foam. thickness not less than 40 mm or styrofoam, but it will cost much more. Both materials have low thermal conductivity And high resistance to damage by microorganisms. The entire floor space is covered with sheets of foam plastic, the joints are glued together with polyurethane foam. A reinforcing mesh is placed on top of the foam and poured screed layer of at least 50 mm. This procedure is necessary if the attic will be used.

Disadvantages of polystyrene foam:

• questionable fire retardant properties, added fire retardants are short-lived
• emits formaldehyde
• there are rodents in it
• a “greenhouse effect” occurs, the room must be ventilated frequently

Technology for installing foam plastic and penoizol

The efficiency of thermal insulation when using penoizol is much higher than when installing ready-made foam boards. The slabs may not fit tightly to the supporting frame, forming cracks and “cold bridges.” Filling with foam insulation saves transportation costs and electricity. Penoizol adheres tightly to the wall thanks to the resins included in its composition. It dries within 15-20 minutes. The only drawback is that it is impossible to fill penoizol yourself. The whole procedure must be carried out by specialists.

To install foam plastic boards you will need:

1. Styrofoam
2. plasterboard sheets
3. metal profile or wooden slats
4. hammer
5. polyurethane foam
6. waterproofing material
7. screwdriver
8. waterproofing glassine, which is made of roofing cardboard and impregnated with bitumen. It prevents moisture from penetrating into the thermal insulation layers.
9. fastening elements - screws and self-tapping screws, sometimes nails
10. hacksaw

There are two ways to install foam boards: frame and glue. Preparatory process the same for both methods. The length and width of the area are carefully measured. These indicators are multiplied, and the area is obtained. Based on it, the appropriate number of foam plastic boards with a thickness of at least 5 cm is purchased. Then the surface is processed, to which the slabs will be glued. Old whitewash and plaster are removed, dust and dirt are washed off. You can even treat the surface antiseptic. Apply a coat of primer to make the surface smooth. If possible, the existing electrical system should be replaced with a newer one.

The glue method has its own nuances. In order for the foam to adhere well to the ceiling surface, it is necessary observe temperature regime not lower than 50C and not higher than 250C . You can use regular tile adhesive as an adhesive. It can also be used to treat the surface to which the slabs will be attached. After it has dried, you can continue installation work. Glue is applied to the foam sheet and the wall, left for 2-3 minutes and the foam is pressed to the surface.

You can also use dowels with large heads. The entire area of ​​the insulated surface is covered in the same way. After insulating the entire ceiling, all joints and cracks are carefully coated with glue or foam to enhance the tightness. Once the glue or foam has dried, you can reinforce the ceiling. To do this, a special solution is applied to foam sheets, into which a fiberglass mesh is immersed. Another layer of solution is applied on top. You must wait until the solution has completely dried and only then continue installation work.

With the frame method of mounting foam plastic, wooden or metal slats so as to form cells. Cell size depends on the size of the foam boards. For example, if the slabs have dimensions of 1/1 m, then the cells must be made 50/50 cm. Accordingly, during installation, the foam sheet will need to be cut into 4 equal squares. In case of use aluminum profile, metal slats are attached to the ceiling using a hammer drill and self-tapping screws.

A sheet of foam plastic is inserted into the resulting grooves, coated on the side on all sides with “liquid nails” for reliable gluing of the slabs to the supporting structure. A whole sheet of foam plastic is inserted into the aluminum slats and secured with self-tapping screws. Further also reinforcement is being carried out: a special solution is applied, a reinforced mesh is placed and a layer of fill is applied again. That's it, the insulated ceiling is ready. If desired, you can sew plasterboard over entire foam boards.

Penoizol as insulation for ceilings

Penoizol is foamed plastic in liquid form. To install penoizol, special equipment must be used. It's not very expensive, and it's easy to fill hard-to-reach places. Penoizol is fireproof, hygroscopic, and has low thermal conductivity. There are no rodents in it, and it is not susceptible to microorganisms. Penoizol can be operated at temperatures from -600C to +800C. The material has high sound insulation properties. The environmental friendliness and safety of penoizol has been confirmed by numerous experiments.

Penoizol installation technology

Done wooden or metal cellular frame, the cells of which are filled with penoizol. It spreads and fills the entire space. Gradually it polymerizes and becomes an excellent insulation material. When using it, you do not need to use either a steam or waterproofing agent.

Warm ceiling using mineral wool

This material is divided into glass wool, ceramic, slag and stone wool. The types of glass wool are modern materials for insulation Rocklight, Technoblock, Technovent, Technolight, Technoruf, Technofas, etc. The raw materials for the production of the material are basalt, limestone, diabase or dolomite. The highest quality mineral wool is obtained from rocks.

When using mineral wool, you must wear work clothes, safety glasses and a respirator, because particles of the material irritate the skin. After installation, mineral wool becomes safe for humans. Before using it, it is necessary to clean the surface of debris and dirt. to the state of pure concrete. The frame for the future floor is made from wooden beams. Measurements are taken, logs are installed, a vapor barrier is laid, glassine is better. Sheets of mineral wool are placed on top of it, but this should not be done too tightly, cotton wool cannot be compressed. To make the floor even warmer, you can lay mineral wool in two layers, and upper layer should overlap the joints of the lower one. Next is placed flooring, which is attached to a wooden frame.

Flaws:

• the material cannot be removed and compacted, because it may lose its thermal insulation properties
• mineral wool must be carefully protected from moisture
• even a small gap can reduce the thermal capacity of the ceiling
• together with mineral wool other moisture-proofing material is also used, which increases the cost and complicates the process
• needs to be changed every 10-15 years

Mineral wool installation technology

First, you need to accurately calculate how much insulation, waterproofing and vapor barrier materials you need to purchase. Remember that when working with glass wool, dust is released that irritates the skin and mucous membrane of the eyes. Therefore it is necessary purchase protective clothing and glasses, respirator, gloves. It is also necessary to turn it off while working with mineral wool. ventilation system so that dust does not penetrate there. For installation of mineral wool you will need the following:

1. insulation
2. wooden slats (width 150 mm, thickness 30 mm) or galvanized profile
3. hammer drill
4. self-tapping screws
5. large scissors
6. protective equipment
7. vapor barrier
8. metal staples
9. roulette

If the house is wooden, then the supporting structure is chosen wooden slats. A waterproofing layer with an overlap of 10 cm is placed on the wooden floor. A sheathing is attached to the top. The distance between the slats is 50−60 cm. Mineral wool is unpacked immediately before installation. The insulation is cut into pieces to a width corresponding to the distance between the slats plus 2 cm for a tight fit.

Between waterproofing and insulation is done a gap of 1−2 cm for natural circulation air. Mineral wool is placed tightly enough so that no folds or crevices form. Then a vapor barrier is attached on top perpendicular to the rafters with an overlap of 10 cm and attached to the wooden slats using a stapler. All seams are carefully secured with mounting film. This will strengthen the tightness of the structure.

It is a cellulose based material, absolutely harmless to humans. 81% ecowool consists of recycled cellulose, a product of paper processing, 12% antiseptic, 7% fire retardants. The fibers contain lingin, which gives the structure stickiness. The material is elastic and elastic enough to prevent shrinkage, and at the same time has a capillary structure, thanks to which the ceiling “breathes”. Ecowool protects the surface from the spread of fungus, and rodents do not live in it. Upon contact with metal structures no corrosion occurs, and in case of fire the material smolders, but does not burn.

• During installation, ecowool releases a lot of dust from boric acid
• installation can only be carried out by specialists using special equipment
• ecowool should not be used near a fire source or high temperatures(sauna), otherwise ecowool begins to smolder

Ecowool installation technology

Manual method ecowool installations complicated and tedious. Material installed by an unqualified specialist reduces its effectiveness by 20-30%. There are two methods of mechanical installation of ecowool: dry and wet. The dry method is convenient for insulating an attic. The use of special Tyvek-type membrane films makes it possible to pump ecowool not only into horizontal, but also inclined and vertical surfaces. For this purpose on special equipment Fill cavities of building frames with ecowool under air pressure.

The wet installation method arose due to the ability of ecowool, when wetted with water, to stick to any surface due to the special substance lignin included in its composition. Soaked ecowool groans viscous and sticky, and with the help of a pneumatic installation under air pressure, ecowool is sprayed and adheres tightly to the surface. After drying, a uniform and homogeneous layer is formed with soundproofing ability.

If it is not possible to cover the surface, then use wet-adhesive application method ecowool. With this method, ecowool is treated not with water, but adhesive solution, which significantly enhances the adhesive ability of the material.

Ecowool insulation should be carried out by specialists, then the material will 100% realize all its advantages.

How to insulate a ceiling with sawdust

This method obsolete, but is still used for insulating ceilings.

Flaws:

• they shrink, they need to be added
• fire hazardous

Technology for installing sawdust insulation

First you need to replace the electrical wiring, insulate it in metal pipes and also insulate the chimney. To use sawdust as insulation you will need:

1. sawdust
2. lime
3. cement
4. copper sulfate

Preparing sawdust for laying. It’s difficult for one person to cope; an assistant is needed. In a large spacious barrel, 10 buckets of sawdust, 12 buckets of lime and 1 bucket of cement are mixed. Everything is mixed well until a homogeneous mass is obtained.

Water is poured into a 10 liter watering can and poured a few tablespoons of copper sulfate as an antiseptic. Slowly the contents of the watering can are poured into the barrel with the sawdust mixture. If, with a clenched fist, the mixture ceases to release moisture, then it is ready for use.

Glassine is spread around the entire perimeter of the ceiling and secured with adhesive tape or galvanized clamps. On the surface of glassine The sawdust mixture is laid out in an even layer. There is no need to compact it too hard. Smooth the surface and allow it to dry for at least 2 weeks. That's it, the insulation is ready. It’s just not recommended to walk on it, so the room should not be used.

Thermal insulation of the ceiling with clay

Clay is considered environmentally friendly, fire resistant and inexpensive means of roof insulation. To use sawdust and clay as insulation you will need:

• sawdust
• lime
• cement
• copper sulfate

Technology for installing clay insulation

From beams, bars and boards, treated with antiseptic, a special covering is made (described earlier) into which the clay will be poured. The bottom of the ceiling is lined with polyethylene or PVC film, which is attached to beams and boards using a stapler. In a concrete mixer or large barrel there are 5-6 buckets of clay (which you can dig up in your garden) dilute until completely dissolved with water. Then sawdust is added and mixed until the mixture is not too wet or too dense. The resulting mixture is laid out on the floors between the beams in a layer of 5-10 cm. It is necessary to wait until the clay dries completely. This may last more than a month. To speed up the process, you need to ensure good ventilation in the attic. On a clay surface small cracks may appear, but they are easily overwritten later.

Flaws:

• under clay the tree can become moldy and rot
• if the ratio of clay and sawdust is incorrect, thermal conductivity increases and heat is lost

Expanded clay for ceiling insulation

Expanded clay is lightweight fireproof material, made from baked clay of low-melting grades. Glassine is placed on the floor and lined with reinforcing mesh, Expanded clay is poured on top of all this. It is heat and sound insulating, resistant to moisture, and does not harbor rodents. Expanded clay acts as a thermal cushion, which is poured on top with a screed. For installation of expanded clay insulation you will need the following:

1. expanded clay
2. waterproofing agent
3. vapor barrier
4. adhesive tape, aluminum tape
5. stapler
6. staples

Installation technology for expanded clay insulation

This technology is similar to the technology for laying other insulation materials such as clay or sawdust. First, it is cleaned of contaminants and old whitewash the surface on which expanded clay will be poured. A cellular structure is made from wooden beams over the entire surface. Then, with an overlap of 10 cm, they spread wide strips of waterproofing. The joints are glued together with tape. After fastening, a reinforcing mesh is placed on top of the waterproofing material and a layer of expanded clay is poured. Its surface is leveled. A vapor barrier sheet is spread over the expanded clay layer and attached to wooden slats stapler or metal staples. A vapor barrier is placed on top of the expanded clay layer and beams, which is also secured to the wooden structure with a stapler and staples.

Flaws:

• heavy material
• air “walks” between the granules
• requires subsequent filling or vapor barrier
• Special equipment is required for quality work

Foil insulation

Wood itself is a regulator of heat and humidity, so foil insulation is best used in a room with a concrete floor. When using it, you can eliminate the use of a vapor barrier. The foil itself good heat conductor. Foiled polystyrene foam is produced in sheets of 60/120 cm and has a thickness of 2−10 cm.

The sheets have stepped locks to eliminate “cold bridges”. Foil polyethylene foam can be single-sided or double-sided. The material also has a thickness of 2−10 cm, and is produced in rolls 1−1.2 m wide and 25−30 m long and looks like a carpet. Sometimes foil polyethylene is covered with a layer of mineral wool on top. Thus, thermal insulation is enhanced, and the release of carcinogens from mineral wool is also reduced. Foil glass wool is produced in the form of mats, supplemented with reinforced mesh. Typically, foil insulation is used to insulate the ceiling and walls of a bathhouse or steam room.

Installation technology for foil insulation

Using the method described above, a cellular structure is made from wooden beams or metal strips. Cut to cell size using scissors required size foil insulation and secured with a construction stapler. The foil side should “look” at the room, and not at the floor. Sometimes manufacturers produce foil insulation with already applied to the surface layer of glue.

Sheets of foil insulation are placed end to end, and the joints are glued with special aluminum adhesive tape. This results in a surface that perfectly reflects heat rays. If you plan to use plasterboard or lining over foil insulation, then you need to create an air gap of 1-2.5 cm between the insulation and final finishing. Otherwise foil will heat up and warp the building material. That's it, the insulation is ready. Simply and easily!

Flaw- wood under foil insulation can collapse and rot if not laid tightly.

High-quality insulation of the ceiling in the house allows you to retain heat in cool weather and prevent the room from heating up in hot weather. Insulating the ceiling in a private house means winning economically and increasing the level of comfort. But how to insulate a ceiling for less? The market offers a large selection of solutions for this.

First steps when insulating the ceiling: general rules

Insulating the ceiling is a necessary measure, despite the high labor costs. As a result, the owner will receive comfortable living conditions with low fuel consumption for heating in winter.

How to insulate the ceiling in a house? Main rules:

1. Choosing an environmentally friendly and safe material.
2. The insulation must be made of non-combustible material.
3. The material must have not only thermal insulation properties but also high level, but also not to disturb the natural humidity. That is, he must breathe.
4. The material should not be exposed to moisture.

Note! Only compliance with all parameters guarantees high quality thermal insulation after work.

Preparatory work: selection of material

5 materials meet the above criteria. They are recommended for use when installing a thermal insulation layer on the ceiling of a private house with your own hands:

1. Styrofoam. A polymer characterized by fire safety and lack of sensitivity to moisture.
2. Penoizol. A polymer with a porous structure that has an unlimited service life.
3. Mineral wool. Its peculiarity is that it absorbs moisture, so water in one form or another should not get on it. The most popular material.
4. Ecowool. Saves heat no worse than its mineral counterpart. Produced on the basis of cellulose.
5. Expanded clay. Made from clay - a natural component. The advantage is that rodents never breed in it. In addition, expanded clay is not afraid of moisture. Loose.

Only the last 2 materials are natural. But the others don't either negative influence on human health.

You can create a warm ceiling using budget funds, which you always have in abundance at hand:

1. Slag. Negatively affects the service life of floors. Emits a small amount of radiation.
2. Sawdust. Over time, they are spoiled by insects, losing some of their properties.
3. Dry grass. Promotes the establishment of insects and rodents.

Economical solutions have disadvantages, but have the right to be used in non-permanent housing and outbuildings the old type, where it is a pity to invest large amounts of money - in dachas, old houses or in a bathhouse.

Installation of insulation: location options

The main heat loss in the house occurs through the ceiling of the last floor, above which there is an attic with a roof. Accordingly, there are 2 methods of installing insulation:

1. Outer.
2. Interior.

Both methods give the desired result. But there are differences. They depend not only on the installation features, but also on what materials are used. Namely:

• Vapor permeable.
• Waterproofing.

That is, this is how a material can work with moisture - absorb and let it through or repel it. For interior finishing, a vapor-permeable material is used, and for the exterior, water-repellent material is used.

It is used if there is no attic above the residential floor. Required:

1. Install the frame. Typically made of wood, on the floor of the attic. The final design depends on the insulating material.
2. Fill the frame with heat-insulating material.

At this point, the insulation layer can be left untouched. However, if the attic is periodically used for domestic purposes and you have to walk on its floor, then the insulating layer needs to be covered:

• Concrete.
• Plywood or clapboard.

Internal insulation

If there is a regularly used room above the living space, in the form of an attic or warehouse, it is advisable to use an internal insulating structure. Disadvantages of this method:

1. Labor intensive.
2. Reducing the height of the walls.

Note! At internal way Laying insulation will require waterproofing between the insulation and the ceiling. It is needed if a vapor-permeable material is used.

When building a new house, if the project did not provide for internal insulation, it is enough to make changes to the project. But for a house that has already been put into operation, this can become a problem, especially with a low ceiling height. And if the design of the wooden ceiling can be changed, then concrete ceiling cannot be changed.

To carry out the work, a frame is also formed, which is filled with insulation. The structure is then covered with plasterboard.

Note! The peculiarity of using cotton wool (mineral and eco) is that it cannot be compressed to reduce its thickness. It contains pores that reduce its thermal conductivity. Therefore, it should be used with caution for interior decoration.

Examples of work performed

Each material is unique and must be laid on the ceiling using its own, separate technology. Required materials and tools:

• Boards or metal profiles to form the frame.
• Insulation.
• Cutting tools.
• Fasteners
• Protection - glasses, respirator, gloves.

Nuances of the work being carried out:

1. There should be no breaks in the vapor barrier film. Including between the seams. The purlins should be overlapped.
2. In the frame, the distance between the slats should be 1-2 cm less than the width of the insulation sheet. The height of the frame is 1-2 cm higher than the thickness of the insulation to ensure air circulation to the waterproofing layer on top.

Below are ways to insulate the ceiling with popular insulation materials.

A bulk material that has gained popularity as a thermal insulating layer for floors. Lately it is used as an inexpensive insulation for the ceiling. Characteristics:

• Not subject to oxidation, including combustion.
• Does not emit harmful substances.
• Does not attract rodents and does not become covered with fungus.
• Inferior to cotton wool and polystyrene foam in thermal insulation properties.
• Heavy. Use only on strong ceilings with support beams.

Installation technology:

1. A layer of vapor barrier is laid on the floor of the attic. You can use regular film.
2. The niches between the beams are filled with expanded clay. It is advisable to use fractions different sizes to form several layers. Thickness - at least 20 cm. In cold climates - from 40 cm.
3. The material is leveled.
4. A vapor barrier is installed on top.
5. Laying the floor.

An alternative material is foam glass. It retains heat better.

This material is called liquid foam. Special additives make it non-flammable and repel rodents. The disadvantage of the installation is that you need qualified workers with equipment who can properly insulate.

The technology is simple. Penoizol with a layer thickness of 20-30 cm is poured onto the vapor barrier, which has been previously covered. If necessary, a floor can be mounted on top.

insulation ceiling mineral wool is the most popular method. Easy to do with your own hands. Types of mineral wool:

1. Slag-like. Made from blast furnace slag. Unsuitable material for insulation due to increased hygroscopicity and high thermal conductivity.
2. Stone. Made from rock with the addition of clay. Has low thermal conductivity.
3. Glass wool. Has the lowest thermal conductivity. It is characterized by low cost. Upon contact with human mucous membranes, it causes irritation.

Installation order:

1. Lay a vapor barrier layer.
2. Mount the frame.
3. Place cotton wool.
4. Attach waterproofing to the wool.

Polymer cellular material. Thermal insulating properties are similar to glass wool. Material properties:

1. Low cost.
2. Light weight.
3. Flammable, releasing toxic substances. When heated, they can also be released.
4. Rodents can build a nest in it.
5. Contributes to the greenhouse effect.

Installation options:

• Using a frame.
• For glue.

The foam is placed on the frame similar to the method with cotton wool. However, you should first apply liquid nails to the frame slats and top part polystyrene foam. Installation with glue:

1. Cleaning and washing the installation surface. You will need a primer.
2. Apply glue to the top of the foam and press the sheet to the ceiling surface.
3. The glued sheets are covered with a layer of plaster and then reinforced with reinforcing fiber. Plaster is also placed on top of it.