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Insulation of attic floors with iron beams. How is the process of insulating attic floors using wooden beams? Insulation technology

Ask any builder about the need to insulate structures, and he will definitely tell you that all buildings in which people are supposed to live and work need to be insulated.

The only exceptions are temporary buildings where people spend little time, small architectural forms and buildings that are located in very warm climatic zones.

For these buildings, thorough thermal insulation is not needed, since the temperature outside, even in winter, does not drop to extreme values. Particular attention should be paid to the insulation of attic floors. This process will now be discussed.

1 Features and purpose

The insulation of floors should be given no less attention than the insulation of walls or floors. Someone may object, they say, why concentrate on thermal insulation of floors, if it is much more important to protect walls from heat loss.

Indeed, the walls are almost the main structure that cools the house even with. This is explained by their large area, length and thickness. Wall in winter time years can freeze, thereby seriously lowering its temperature, and therefore the temperature inside the room.

There is another point that concerns the expenditure of resources on heating the house. Excessive heat from radiators can warm up the wall completely, but it will transfer almost half of the thermal energy to the outside.

In professional jargon, builders call this process “heating the street.” As you yourself understand, this is at least an unprofitable use of resources.

However, attic floors have no less priority. To understand why calculations and installation of thermal insulation for floors are needed, it is worth turning to the laws of physics.

According to these laws, warm air always tends upward, and cold air is located below. If we are talking about a house or a room, then here the space is closed most of the time, and therefore the air has nowhere to go. As a result, warmer air currents are located mainly under the ceiling.

If your ceiling is cold, then they cool down and fall lower, making room for air with a higher temperature. The result is a kind of reverse circulation, when the temperature in the room slowly drops, and all because of the uninsulated ceiling, which has a lower temperature.

It is especially important to insulate attic floors. After all, the attic is, in fact, an unused room. It is rarely insulated properly, leaving it as a kind of buffer space. Therefore, the temperature inside, although higher than outside, is still quite low.

If you have monolithic or prefabricated attic floors, then you are very lucky. Concrete, although it does not withstand loads very well, is still a material with high density. It cools slowly and creates significant barriers to low temperatures.

However, in many buildings the attic floors are laid on wooden beams. The device on wooden beams makes it possible to do the work yourself and significantly reduce the cost of arranging the floor, but its thermal insulation properties can hardly be called acceptable.

The simplest ceiling of this type consists of beams onto which wooden boards, and the insides, at best, are filled with a small screed or backfill materials.

2 Types of materials for floor insulation

Let's turn to specific insulation materials that are most often used for thermal insulation of floors.

Insulation materials can be very diverse, their thickness and optimal characteristics determined after all parameters have been calculated.

However, calculation is not always necessary. So, if you are going to insulate a standard attic floor with a reinforced concrete slab base, then 7-10 cm of mineral wool insulation or about 5 cm of penoplex insulation will be enough for you.

If it is necessary to protect floors using wooden beams, then the required thickness will be slightly larger, since wooden floors, even with filling, do not provide the same resistance to temperature loss. Therefore, a larger layer of insulation will have to be laid on top of the main structures along the beams.

2.1 Insulation technology and its nuances

You can insulate the attic floor yourself. Especially if you need to work with wooden beams. Everything here is already prepared for work. All you need to do is fill the space between the beams and do it as efficiently as possible.

Stages of work:

It almost doesn’t matter whether you use mineral wool or polystyrene foam materials; in any case, they are installed using the same technology.

If necessary, they can be additionally secured with dowels, but only if your floor has a base and does not consist of beams alone, on which boardwalk is placed on both sides. Steam and waterproofing are attached using a conventional stapler to the beam elements or sheathing.

2.2 Insulation of the floor with liquid polystyrene foam (video)

Since the roof of a cold attic only serves as protection from rain, snow and, partially, wind, special attention should be paid to the thermal insulation of the floor. Insulation of the attic floor is carried out using various heat-insulating materials with mandatory wind protection, especially from the eaves of the roof.

Insulating the floor in two layers using mineral wool rolls

As a rule, insulation is laid directly on the floor of a cold attic. Naturally, provided that the attic will not be used. This will allow you to save on a layer of waterproofing film, as well as on organizing a full floor covering.

Read below to learn how to insulate an attic floor and what materials can be used for this.

How thick should the attic floor insulation be?

The thickness of the thermal insulation layer does not depend on which attic floor construction using wooden beams or reinforced concrete is chosen. On the packaging of any insulation, the coefficient of thermal conductivity λ is indicated, and it has two values: λA - for a dry environment, and λB - for a wet environment. The lower this coefficient, the better the insulating properties of the material. It is on the basis of this value that the calculation of the insulation of the attic floor is made.

The thickness of the attic floor insulation is:

α = R 0 ·λB

where R 0 is the heat transfer resistance coefficient, which, according to standards, is equal to 4.15 m² °C/W.

Insulation of the attic floor using wooden beams

In the majority small houses and dachas with cold roofs, wooden floors are used, so it is their thermal insulation that we will consider first.

The installation of an attic floor on wooden beams is usually as follows:

1. Lower floor filing.
2. Vapor barrier.
3. Floor beams.
4. Insulation.
5. Waterproofing.
6. Finishing.

The installation of a ceiling in a private house with a cold attic begins with the installation of load-bearing beams. Since their maximum length is usually 4 meters, for rooms of greater width it is necessary to either construct supports or use metal purlins.

Diagram of a wooden attic floor with two layers of insulation

After the beams are laid, a vapor barrier is made for the cold attic floor. To do this, a vapor barrier film is attached to them from below, which protects the insulation from moisture penetration from the lower room. When you insulate a wooden attic floor, it is advisable to use special reinforced multilayer materials made of polyethylene or polypropylene as a film, since they are stronger and much easier to attach.

It is best when the vapor barrier layer is continuous. However, the design of a wooden attic floor does not always allow this. If for some reason the vapor barrier cannot be placed under the beams, the film is laid between them with an overlap on them and fixed with special tape to ensure tightness.

Don't forget about wood impregnation

The installation of a wooden attic floor involves the risk of damage to the load-bearing structures due to rotting. Therefore, before laying a cold attic pie, all wooden beams and sheathing should be impregnated with special solutions that prevent rotting and mold formation.

Next, the attic floor is insulated along the beams, for which heat-insulating material is laid between them. If you use loose insulation, then it should be carefully leveled and ensure that it fills all the voids.

The minimum thickness of thermal insulation for insulating an attic wooden floor, calculated by you using the formula above, may be greater than the width of the load-bearing beams. In this case, a sheathing of bars of the size you need is attached across them. Then another layer of insulation is laid between them with the obligatory overlap of the joints of the previous layer.

Avoid the formation of cold bridges

Close attic beams overlapping with a layer of thermal insulation is recommended even if their width is sufficient to accommodate the insulation of the calculated thickness. The fact is that so-called cold bridges are formed through them, and therefore heat loss in the house increases.

A wood-beam attic floor is usually constructed with a floor of conventional decking made from treated boards laid across the sheathing or support beams. However, thick plywood, chipboard, MDF and other similar materials can also be used as a finishing coating.

If as finishing If you want to use a leveling screed, then waterproofing the cold attic over the insulation layer is mandatory.

Insulation of the attic floor on a reinforced concrete slab

If you need to insulate the attic floor using reinforced concrete slabs, then this can be done in two ways: with or without lathing.

The first method is universal, but is most often used for light types of insulation. The design of the attic floor of a cold attic in this case will look like this:

1. Vapor barrier of the attic floor is being carried out cold attic, which should cover the entire layer of insulation also from the sides. Since the vapor barrier simply needs to be laid on the floor, it is not necessary to use specialized materials for these purposes - regular one will do cheap plastic film.
2. On top of the film with the narrow side a wooden block is placed a width equal to half the required thickness that the insulation for a cold attic should have. The distance between the bars is usually taken equal to the width of the roll or slab of the selected brand of insulation.
3. Between the boards Installing insulation for the attic floor. If it is necessary to use several layers of heat-insulating material in thickness, it is laid with overlapping joints of the previous layer.
4. Exactly the same ones are attached across the already laid bars, at a similar distance from each other. A second layer of attic floor insulation is laid between them.
5. Above vapor-permeable waterproofing of a cold attic is installed, which is secured either with a special adhesive tape or with a thin bar nailed along the sheathing. This stage can be omitted if high-quality waterproofing of a cold roof made of corrugated sheets has already been performed.
6. Across the bars floor boards are nailed or walkways are laid for movement.

So how to properly insulate the ceiling under cold roof It is very important to save on heating the house, I recommend using exactly the given transverse diagram for laying thermal insulation. This arrangement of the attic floor minimizes the possibility of the formation of a cold bridge through wooden blocks, since most of them will be insulated with insulation.

The second method of insulating a cold attic using reinforced concrete slabs without using lathing is suitable in cases where moisture-resistant solid types of insulation that can withstand significant loads without loss of properties are used for thermal insulation.

Scheme of the attic floor installation on a reinforced concrete slab

In this case, the vapor barrier of the attic floor is also installed first. Next, the attic floor slabs are insulated with a layer of thermal insulation of the calculated thickness.

A leveling screed is poured over it. The finished floor is already laid on the screed. If the insulation of a concrete attic floor is carried out with aerated concrete and materials similar in density and properties, then you can do without hydro- and vapor barriers, as well as screeds.

Insulation for attic floors: which one to choose?

Before insulating the attic floor, you need to select a heat-insulating material that is suitable specifically for your case. Unfortunately, there is no universal option for the best way to insulate the attic floor. This choice depends on many factors, the most significant of which are:

• heat-insulating properties of the material;
• fire safety;
• price;
• ease of installation;
• environmental friendliness;
• hygroscopicity;
• strength;
• resistance to rotting, temperature, acid and alkali.

You must decide which of these factors are most important to you and which can be neglected.

Insulating the ceiling of a cold attic with mineral wool

Mineral wool is one of the most popular materials for floor insulation. The best characteristics In order to thermally insulate the attic floor of a house, there is a type of it based on basalt fibers, which is called stone (basalt) wool.

Insulation based on basalt fibers belongs to the class of non-combustible materials with a melting point above 1000 °C; and has excellent thermal insulation properties. However, it easily absorbs moisture, so when using it, the requirements for hydro- and vapor barrier are particularly high.

It is better to insulate the attic floor with mineral wool using rolls, since the joints between the slabs, although not much, do reduce the effectiveness of thermal insulation. It must be laid close to the beams or guides, but avoiding jamming.

Mineral wool laid in two layers when insulating the attic floor

Installation of mineral wool is very simple, so this thermal insulation material is most often chosen when they want to insulate an attic floor with their own hands without the involvement of specialists. While working, do not forget to use the tools personal protection: Thick rubber gloves, glasses and clothing that covers the entire body. For people prone to allergies, this kit must be supplemented with a respirator.

Advantages:

• Fire safety;
• Environmental friendliness;
• Ease of use;
• Relatively low price.

Flaws:

• Tendency to form compactions, good crushability;
• Hygroscopicity.

Insulating the attic floor with foam plastic

Polystyrene foam is a very inexpensive material, which, in fact, is foamed polystyrene foam and, due to these “bubbles” with air, retains heat. It is cheap, has good heat-insulating properties, is moisture resistant and can withstand fairly large compressive loads.

Foam boards of different thicknesses

However, all its advantages are more than offset by one drawback - this material is fire hazardous. Already at a temperature of 80 °C; foam melts releasing a huge amount of harmful substances, and at temperatures from 210 °C; a fire occurs. Therefore, insulating the attic floor over wooden beams with polystyrene foam is not the most good idea. However, it can be used between non-combustible materials, for example, when laid as insulation on a concrete slab with screed poured.

Advantages:

• High thermal insulation properties;
• Low price;
• Moisture resistant;
• Resistant to rot;

Flaws:

• Fragility;
• Very flammable;
• Deforms already at a temperature of 60 °C;
• It is an excellent refuge for mice.

Insulation of attic floors with extruded polystyrene foam

Extruded (extruded) polystyrene foam is made from the same material as polystyrene foam, but using a fundamentally different technology. In the CIS, the most common insulation materials of this type are from the Penoplex company. The performance properties of extruded polystyrene foam are much better than those of polystyrene foam, especially with regard to the ignition temperature of the material.

Extruded polystyrene foam in slabs of various thicknesses

However, insulating a wooden attic floor with penoplex is still not recommended. Despite the fact that open combustion of this heat-insulating material occurs at a fairly high temperature, it is still a fire hazard. Firstly, extruded polystyrene foam supports combustion, and secondly, it releases very caustic and toxic substances when heated to even very low temperatures, and they are the cause of death in a fire in most cases. Therefore, penoplex is far from a better option than insulating the attic floor of a house, even if it is reinforced concrete.

Advantages:

• High thermal insulation properties;
• Moisture resistant;
• Resistant to rot;
• High density;
• Withstands fairly heavy loads;
• Light weight.

Flaws:

• When heated above 80 °C; begins to release toxic substances;
• Fire hazardous;
• Deforms when heated.

Insulating the attic floor of a house using polyurethane foam

Polyurethane foam boards are one of the best existing insulation materials. This material has excellent thermal insulation properties, it is durable, resistant to chemical and bacteriological influences, non-hygroscopic and fireproof.

Polyurethane foam insulation in the form of a plate with foil coating

Polyurethane foam is the best way to insulate the attic floor in a private home. If you can afford it. The high cost is its main and probably only drawback. Because of this, it may even be difficult to purchase this material in small towns.

Advantages:

• The best thermal insulation properties among the materials considered;
• Fireproof;
• Not affected by moisture and chemical substances;
• Does not rot;
• Eco-friendly;
• Convenient to use.

Flaws:

• Price.

Insulating the ceiling of a cold attic with sawdust

Previously, in the absence of other materials, insulating a cold roof with sawdust was a widespread phenomenon. Now this method of thermal insulation is used by those who like its environmental friendliness. At the same time, despite popular belief, the design of an attic floor using such insulation is by no means cheap. Sawdust is not laid “dry”, but in a special solution, the production of which requires money and a lot of time.

The composition of a sawdust solution for insulating a cold attic is as follows:

• 10 buckets of sawdust(we need wood sawdust, which is formed during sawing and processing of wood; furniture sawdust is too small for these purposes);
• 1 bucket of hydrated lime(fluffs);
• 1 bucket of cement;
• 5-10 buckets of water with antiseptic, for example, with boric acid, soap or copper sulfate (pour gradually using a watering can, the final amount depends on the size of the sawdust).

The resulting mixture is placed on the base between the beams and compacted. The thickness of the layer of such insulation for the attic floor should be at least 300 mm, but it is better to do more, since the thermal insulation properties of sawdust mortar can vary greatly. Walkways for movement are laid on top of such insulation to cover the attic, for which sheets of chipboard or thick plywood can be used.

Advantages:

• Comparatively cheap;
• Environmental friendliness;
• Good thermal insulation properties.

Flaws:

• Labor intensive self-production;
• The thickness of the attic floor is large;
• Difficult installation;
• Differences in thermal insulation properties depending on the composition.

Insulation of attic floors with expanded clay

Another relatively cheap material that can be used to insulate the attic floor of a private house is expanded clay. It is made by firing clay and is one of the most environmentally friendly building materials. In addition, expanded clay has good thermal insulation properties, is fireproof, durable and inert to acids and alkalis.

Using expanded clay, you can insulate both reinforced concrete and wooden attic floors. However, in the latter case, you need to carefully consider the calculation of the load-bearing capacity of the beams, since expanded clay insulation weighs much more than modern insulation materials. Concrete attic floor slabs can easily withstand very heavy loads, so expanded clay can be used for them without additional calculations.

Good thermal insulation properties;

Fireproof;

Resistant to acids and alkalis;

Not subject to rotting;

Durable;

Low cost.

Flaws:

• Difficulty in installation.

A room in the attic of a private household is used for various purposes: storing temporarily unnecessary things, installing equipment or arranging living rooms. Depending on what the free space under the roof is used for, the method of constructing the attic floor is chosen.

What is an attic

The attic space is limited by the roof slopes and the ceiling of the residential floor. This place is often used to create additional living space.

There are two types of attics in private households:

1. Residential. It is called an attic. It can be equipped with a living room, study, bedroom, library, etc. The height of the room in this case should be at least 220 centimeters. In addition, it is necessary to provide ventilation, natural lighting, and insulate the slopes.
2. Non-residential. Such attic space is usually used to house technical equipment and store old or unnecessary things. In this case, a 2-meter height will be sufficient, and there is no need to provide natural lighting. Instead of insulating the slopes, they insulate the attic floor.

When making a decision to repair or rebuild a house, you need to decide in advance for what purpose the attic will be used in order to make calculations and a floor design. The list of necessary materials and the gap between the beams depend on this. They must provide the required strength and load-bearing capacity.

Functional purpose of floors

The design of the attic floor depends on the parameters of the structure and the purposes for which it is planned to use the under-roof space. The attic functions as a kind of air gap that separates the cold roof from the heated floors.

The floor in the attic performs a number of tasks:

• carrier. The floor, located between the upper residential floor and the attic space, is assigned a load-bearing function, so it is made reliable and durable, since people will move on it, they plan to place equipment on it and arrange storage areas;
• insulating. In a cold attic, the temperature differs little from that outside the house. In this case, the floors in the attic have a thermal insulating function, thereby preventing the air from cooling on the residential floors. To retain heat, the attic floor needs to be insulated. It is advisable to entrust such work to professionals.

Features of the device and design of floors

Since attic floors perform two functions - load-bearing and insulating, they have a multi-layer structure. Each of the elements of the “pie” complements each other, which ensures the created structure has a long service life, strength and the ability to withstand heavy loads.

The construction of the floor in the attic requires the presence of the following layers:

1. Finish floor. This name is given to the floor covering, which is laid on a rough base. If it is an attic, then when installing the finished floor, linoleum, laminate, parquet, etc. are laid. In non-residential premises there may be no finishing floor covering.
2. Rough base . It is a boardwalk that is mounted on logs. The subfloor is lined with edged boards 4–5 centimeters thick or, to save money, with unedged boards.
3. Lags. These are strong, level pieces of wood that are laid perpendicular to the floor joists to create a floor covering. When installing an attic floor on wooden beams, insulation is placed between the joists, which is protected from below with a layer of vapor barrier, and covered with waterproofing material on top. If you do not use insulating layers, then repairs will be required in a few years.
4. Beams. The frame of the floors is built from thick and strong beams, which are either mounted on the projections of the walls or built into them. They must support the entire weight of the structure. A flat roof can also be made using wooden beams, which is quite practical.
5. Headlining. On the side of the rooms, the floors are decorated with finishing materials, for example, natural wood or plasterboard.

Types of attic floors

To construct the ceiling of a cold attic, materials differing in weight, durability, cost and load-bearing capacity are used.

There are several types of floors depending on what they are made of:

1. Wooden elements. For their manufacture, you can use beams with a cross-section of 150x150 or 200x200 millimeters. The advantage of this option is that wood is quite durable and at the same time relatively light material, so wooden elements do not put additional load on the foundation of the house. In addition, their big advantage is their low price and availability. But such an attic floor is used when the size of the building does not exceed 6-10 meters, since this is the maximum length of lumber.
2. Metal products. Metal I-beams are distinguished by their strength and ability to withstand heavy weight without deformation. But they weigh a fair amount, so they are rarely used in wooden houses, but for brick and aerated concrete buildings they are the best option.
3. Reinforced concrete products. Molded floor beams made from reinforced heavy-duty concrete are used to multi-storey buildings, since they are heavier and the same length.

Of all the above types of floors, in private low-rise housing construction, in most cases, preference is given to wooden beams. They have optimal ratio between price and quality. If the calculations are carried out correctly and the technology is followed, repairs to the ceiling will not be required in the coming years. Ventilation is also necessary in the attic of a private house, the arrangement of which will require additional knowledge.

Requirements for the device of the pie

Since the safety of staying in the house depends on the quality of installation and repair of attic floors, a number of requirements are imposed on their arrangement.

In order to know the maximum permissible load that the structure can withstand, it is necessary to perform the appropriate calculations, and then, based on their results, they begin to develop a project from which it will be clear how to properly insulate the attic floor in the house.

The requirements relate to:

1. Load capacity. It directly depends on the material used to make the beams and the gap between them.
2. Distances between load-bearing elements. The maximum permissible value for this parameter in accordance with building codes is 4 meters.
3. Resistance to temperature changes. It is necessary that the beams can withstand such changes without problems. The fact is that the difference between the air temperature in the residential floors and in the attic always exceeds 4 degrees.
4. Isolation. The attic floor covering of a cold attic should protect the premises of the household from the penetration of cold and moisture from the under-roof space.

During the design process, you should take into account the requirements for the beams used to arrange the floor in the attic so that the result is reliable and durable. The distance between them must be calculated based on the loads exerted on them.

Technology for creating an attic floor using wooden beams

If you have experience construction work You can mount the ceiling of a cold attic using wooden beams yourself. Perform this process on final stage carrying out roofing work.

The sequence of actions will be as follows:

1. Installation of load-bearing beams. For a small private house, wooden floors made from timber with a cross-section of 150x150 or 200x200 millimeters are suitable. They are laid on concrete or brick walls.
2. Installation of lag. They are placed on the edge perpendicular to the beams in increments of 60 centimeters. The logs are made from boards with a cross section of 150x50 millimeters.
3. Laying thermal insulation. The insulation is placed between the joists - it will protect against the penetration of cold from the attic.
4. Installation of rough and finished floors.
5. Covering load-bearing beams on the side of the room to decorate the ceiling surface.

When insulating the attic floor, you should not forget about installing hydro- and vapor barriers.

Most small houses and villas with cold roofs use wooden ceilings, so their thermal insulation is what we will look at first.

Installation of a ceiling on wooden beams is usually carried out as follows:

1. Ground floor;
2. Vapor barrier;
3. The beams overlap;
4. insulation;
5. Waterproofing;
6. Completion.

The ceiling installation in a private house with a cold attic begins with the installation of load-bearing beams.

Since they usually have a maximum length of 4 meters, it is necessary to build supports or use metal programs for larger areas.

Diagram of a wooden attic device by laying the heater in two layers

Once the beams are laid, a vapor barrier is created that blocks the cold attic. To do this, a vapor barrier film is attached to the bottom, which protects the insulation from moisture penetration from the lower room.

When you are performing rigid insulation on a floor, as with film, it is advisable to use special reinforced laminates made of polyethylene or polypropylene, as they are stronger and more firmly attached.

It is best for the protective layer to be hard.

However, construction wooden attic this does not always allow. If for some reason you are unable to place a vapor barrier under the beams, the film is placed between the two overlapping c's and secured with special adhesive tape to ensure a seal.

A wooden attic structure poses a risk of damage to supporting structures due to rotting.

Therefore, before the furnace is placed in a cold attic, wooden beams and strips are impregnated with special solutions that prevent the formation of rot and mold.

The attic roof is then insulated on beams, for which thermal insulation material is placed between them.

If you use loose insulation, it should be carefully aligned and tracked to fill any gaps.

The minimum thickness of insulation for attic insulation on a wooden floor, calculated using the above formula, may be greater than the width of the supporting supports. In this case, the correct size is attached to you.

Then another layer of insulation is laid between them, with the obligatory covering of the joints of the previous layer.

The fact is that they are formed by so-called cold bridges, due to which it loses heat in the house.

Mansardi wood beams typically work with floor decks of conventional treated stacked box panels or cross beams.

However, thick plywood, particle board, MDF and other similar materials can also be used as the final covering.

If you want to use leveling screed as a finish, the cold attic above the insulating layer must be watertight.

Brief instructions for installing attic floor beams

The beams are deepened into the load-bearing walls by 200 mm. Since wood comes into contact with concrete, brick, blocks, etc., the edges of the beams require more thorough antiseptic treatment and waterproofing.

Step 1: In the brickwork, make a monolithic foundation strip for laying the floor beams. This will help securely secure the bars to the base. Place a waterproofing sheet on the base.

Step 2: Make markings for the beams according to the house design. The first thing you need to do is install the center beam. It can have a larger cross-section and serve for installation vertical racks under the ridge beam.

To reduce thermal insulation consumption, match the size of the material to the pitch of the floor bars in advance. This way you will minimize cuttings and make the insulation layer solid, which means it will be of higher quality.

Step 3: Treat the edges of the beams with wood antiseptic and wrap them with waterproofing film. You can dip the ends of the beams in bitumen mastic and lay them on a layer of roofing felt.

Step 4: Place the beams on the load-bearing floors according to the markings. Secure both sides of the beam with reinforced steel corners.

What should the attic floor be like?

The ceiling of an attic or attic must perform four important functions:

External loads, the weight of the roof and internal loads (people, furniture, partitions, equipment, etc.) are taken into account. The calculation depends on the use of the attic. If the premises are non-residential, then you can count on minimal loads; for an attic the floor should withstand an average of 250 kg/m2, and for a residential floor - at least 300 kg/m2.

Noise isolation. Good sound insulation will minimize the sounds of rain, hail, wind and your footsteps if you decide to visit the attic space.

Heat preservation, which always rushes upward and is lost due to poor thermal insulation of the floors. So one more important nuance when arranging the attic floor - choosing a high-quality thermal insulation material.

Insulation from moisture and steam, preventing the accumulation of condensate, the development of microorganisms, insects, mold and rot in the floor layers.

How to determine load resistance:

When starting to cover an attic using wooden beams, we must be confident in the quality of the base, that is, the reliability of the floor beams themselves.

Preparation of materials and tools

Before insulating the attic floor in a private house, it is necessary to prepare lumber, hydro- and vapor barrier, standard carpentry and power tools. Thus, to carry out the technical part of the work, you will need:

From hand tools:

• a pair of hammers (heavy and light);
• rip and cross saw;
• plane;
• set of chisels;
• roulette;
• building level.

From power tools:

• drill;
• screwdriver with replaceable attachments;
• Instead of a crosscut saw, sometimes it is much more convenient to use an electric cutting machine.

For fixation roll insulation It is convenient to use a special construction stapler with staples.

A film made of foamed polyethylene or a vapor-permeable waterproof membrane is suitable for creation. To seal the joints tightly, you will need foil tape.

From lumber you will need bars with a cross-section of 62x62 mm, as well as boards with a thickness of at least 25 mm. To finish the floor, each owner uses finishing materials at his own discretion.

Important! Before carrying out thermal insulation work, all wooden components of the structure must be treated with special antiseptics and, if possible, antipyretics. This will avoid the occurrence of putrefactive or moldy processes in the wood, and will also provide fire-fighting properties.

2 Floor insulation technology

An example of arranging a heat-insulating floor pie along beams

Now let's turn directly to the technology of floor insulation. In fact, there is nothing complicated here. Moreover, the presence of beams and a base already simplifies the work.

Indeed, in most cases you will not have to install an additional frame or anything like that. It will be quite simple to fill the cavity between the beams with insulation and layers of insulation, and then hammer it with boards.

Stages of work during insulation interfloor covering from the floor:

1. We prepare the ceiling and, if necessary, open the boardwalk.
2. We prepare the insulation and all the necessary materials.
3. We lay a layer of vapor barrier. You can work with Izospan or any other suitable vapor barrier film.
4. We install insulation.
5. We lay a layer of waterproofing, if necessary.
6. We fill the cavity with boards.
7. Apply the finishing coat.

If you need to insulate from the ceiling, then the technology here is almost identical. Only you most likely won’t need waterproofing at all. And if it is needed, it will be installed under the covering first.

Then there will be a layer of insulation, which is attached with dowels to the bases of the beams, and then a vapor barrier film.

When working with insulation based on polystyrene foam, there is no great need for a vapor barrier film. Here it is necessary to assess the general situation.

2.1 Installation of insulation in the interfloor ceiling (video)

Functions

The design of the attic floor depends on the size of the house and the nature of the use of the under-roof space. The attic is a kind of air gap that separates the heated space of the first floor and the roof and thermally insulates it.

1. Carrier. The floors between the upper floor and the attic perform a load-bearing function, so they must be strong enough and reliable, because people move around it, equipment and storage areas are installed.
2. Isolating. The room in an unheated attic has a temperature not much higher than the outside temperature. Therefore, the ceilings perform a thermal insulating function, preventing the heated residential floor from cooling down. To retain heat, they include a layer of insulation.

Remember that the correctness and quality of the work on arranging the attic depends on temperature regime, comfort, safety of living in the house. Therefore, it is better to entrust the design, installation or repair of floors to professional craftsmen.

Attic floor diagram

Which heat and sound insulating material is better to use?

The building materials market offers a fairly wide range of insulation materials for interfloor ceilings with good sound insulation performance. The option can be found either the cheapest or the most expensive, environmentally friendly or the warmest.

Installation of a mineral wool insulated beam interfloor structure of a cottage

You can insulate the first floor floor using wooden beams using:

• mineral wool (basalt or glass);
• vibration damping materials based on synthetic rubber;
• glass canvas with non-woven fiber as the outer layer;
• fiberboard slabs;
• extruded polystyrene foam (EPS);
• silica fiber mats;
• isolon (foamed polyethylene with foil);
• construction felt;
• ecowool made from cellulose.

In addition, there are ZIPS on sale - sandwich panels made of two gypsum boards and insulation between them.

Advice! The cheapest is mineral wool, but the particles of glass or basalt from which it is made are harmful to health. It is better to take ready-made mats made of non-woven canvas with mineral wool inside. The insulation from them will definitely not crumble.

Izolon is ideal for installation from the ground floor with the foil down. It reflects perfectly thermal energy, has good sound insulation performance for impact noise and is an excellent waterproofer. But it alone will not be enough on the floors; something else will have to be laid between the beams.

EPPS provides good sound insulation and insulation for interfloor slabs, but in terms of environmental friendliness it is much inferior to almost all other options. Plus it is flammable, like felt or ecowool. Medium and low density fiberboard slabs have good heat and sound insulation characteristics. However, they have considerable weight, which can lead to overloading of the beam floor.

Mineral wool has good sound absorption and thermal insulation. The fibers inside it are located under different friends corners to each other in a chaotic manner. On the one hand, they cushion and absorb sound vibrations, and on the other, the air between them is an excellent heat insulator.

The most affordable and popular option for insulating floors in a cottage is a cake made from mineral wool and vapor barrier film

The final choice of insulation for interfloor beams depends on the personal preferences of the owner wooden house. All of the listed materials are suitable, you just need to choose the right thickness to ensure the required heat and sound insulation.

Installation process

Having decided on the material for thermal insulation, the question arises: how to properly insulate the attic floor? If we talk about mineral wool, what density should it have and what layer of insulation will be best?

Selecting the layer and density of mineral wool

It is better to do insulation with mineral wool in two layers

In short, the larger the layer of mineral wool, the better. However, you need to remember that mineral wool has its own coefficient of thermal conductivity. The lower this coefficient, the higher the thermal insulation properties, and, therefore, it is possible to lay a smaller layer of wool or have greater insulation efficiency. Mineral wool with a thickness of 15-20 centimeters is often used, however, to ensure increased thermal insulation, a 30-centimeter layer of insulation can be used. It is also worth noting that with equal insulation thickness, two layers of mineral wool are always better than one.

You also need to pay attention to the density of mineral wool, because it varies: from 30 kg/m3 to 220 kg/m3. Thermal insulation properties practically do not depend on density

Denser insulation is used for facades and floors under screed. Mineral wool with a density of 35 kg/m3 is also suitable for attic flooring, since the insulation will be located on a horizontal, non-loaded surface.

Vapor barrier

Since mineral wool tends to absorb moisture, you need to start insulation by laying a vapor barrier material.

Vapor barrier - the first layer of insulation

Important! It is best to lay a layer of vapor barrier under the wooden beams, because otherwise they will be very susceptible to rotting. However, if it is impossible to install a vapor barrier film under the beams, they need to be impregnated with solutions that protect against rot and mold.

The best option is to lay a continuous layer of vapor barrier, but due to the size of the attic this is not always possible, so all joints must be taped with special tape to ensure tightness

The edges of the vapor barrier must be raised above the level of the future insulation and taped with the same tape.

The best option is to lay a continuous layer of vapor barrier, but due to the size of the attic this is not always possible, so all joints must be taped with special tape to ensure tightness. The edges of the vapor barrier must be raised above the level of the future insulation and taped with the same tape.

Thermal insulation

When working with heat-insulating materials, you need to wear special clothing

Next comes the installation of insulation. It must be laid so as to completely fill the entire space between the wooden beams. If we are talking about mineral wool, then it does not need to be pressed or squeezed. It should completely cover the space between the beams, leaving no cracks or gaps. It would also be a good idea to cover the floor beams themselves with heat-insulating material, because they can serve as a kind of cold bridges.

When laying mineral wool, it is very important to protect yourself, and especially your respiratory tract, from insulation fibers. Therefore, you need to use a respirator, as well as gloves, goggles and long sleeves.

Waterproofing

We complete the insulation of the attic floor with waterproofing and subfloor installation

Due to the property of mineral wool to absorb moisture, waterproofing must be laid over the layer of mineral wool. This is also necessary if the insulation will be poured over concrete screed.

If the attic is constantly used, a subfloor can be made on top of such a heat-insulating “pie”. Its role can be a concrete screed or OSB boards. If the attic is practically not used, then you can simply lay boards on top of the existing beams. Then, if necessary, go up to the attic, moving around it will not create difficulties.

As you can see, insulating the attic floor is an accessible task, even for those who have never done it. You need to decide on the material for thermal insulation, although most often it is mineral wool. When installing a heat-insulating “pie”, it is important to remember the need for vapor barrier and waterproofing. This will allow you to achieve high results in insulating the attic floor.

A few words about floor beams

I. Don't skimp on wood

For beams it is better to choose bars from quality wood cross section from 100x150 mm or more. Such material will make the floor durable, resistant to deflections, loads and wear. Is it possible to use boards with a smaller cross-section? It is possible, but then it is necessary to additionally strengthen the ceiling with transverse bars - spacers, which are mounted between the beams in a checkerboard pattern. This will help avoid deformation of the boards. You can also further strengthen the attic floor with double lathing.

II. The tree must be dry

It is important that the moisture content of the wood beams does not exceed 20%, otherwise, after drying, the structure may become deformed and lead the attic into disrepair. High-quality antiseptic and fireproof wood treatment is required! . III

Optimal spacing of floor beams

III. Optimal spacing of floor beams

The optimal frequency (pitch) of floor beams for floor strength is about 60 cm. There is no point in making the distance smaller, since it is necessary to provide attic hatch, through which you can climb into the room. If it is an attic, then the distance between the beams is increased to 100-120 cm. In this case, you should think about using metal beams that have greater load-bearing strength or reinforcing the beams with transverse links.

IV. Don't forget about distance

Do not also forget that the maximum distance between load-bearing walls on which the beams rest – no more than 4.5 m.

Insulation of attic floor slabs with extruded polystyrene foam

Expanded polystyrene or polystyrene foam are not very dense materials, so they are used when the attic floor is a structure made of joists and beams. If thermal insulation of the slabs is necessary, insulation of the cold attic floor with extruded polystyrene foam is used. This material is stronger and therefore denser than regular foam. Before laying it, the surface of the slabs should be leveled. There is no need for vapor barrier on the warm side of the floor, since concrete slabs have almost no vapor permeability.

A vapor barrier film is laid on the leveled concrete slabs. Next, slabs of extruded polystyrene foam are laid in a checkerboard pattern. The joints are blown out polyurethane foam. After the foam has dried and hardened, the insulating slabs are poured with concrete mortar 4-6 cm thick. When the screed is dry, it is already suitable for use as a floor. Although you can go further and put any floor covering on the screed.

Thermal insulation of a cold attic with ecowool

Ecowool is a cellulose, lightweight and loose insulation material consisting mainly of waste paper and newspapers. Other ingredients are borax and boric acid are used as flame retardants.

Before insulation, it is necessary to place a film on the floor. The procedure for laying ecowool occurs using a special blowing installation. The insulation layer is applied as a continuous cover, without creating cracks. Since ecowool contains a large amount of air, a layer of 250-300 mm is usually enough.

Do not forget that over time, the material will shrink. Therefore, apply a layer of ecowool 40-50 mm more.

After the insulation of the cold attic floor with ecowool is completed, it must be moistened. You can do this with plain water or prepare a solution of 200 grams. PVA glue on a bucket of water. Soak a regular broom in this solution and moisten the cotton well. After drying, a crust forms on the surface of the cotton wool - lingin, which will not allow the cotton wool to move.

As you can see, there are plenty of ways to insulate the floor in the attic. Which one to use depends on each specific situation. The main thing is to comply the right technology laying thermal insulation! Then your home will always be warm, and the materials used will last for many years.

Types of insulating material for floors

Insulating the attic with sawdustis a thing of the past, currently the thermal insulation of the attic floor is carried out with modern materials (for example, ecowool) that meet building regulations and the requirements given above. Main types:

1. Mineral (basalt wool). This insulation is produced by many manufacturers and is currently very widespread. It is very environmentally friendly because it consists of basalt fibers mixed with stone chips. This is high-quality protection against rodents, the material is durable, resistant to moisture, and does not lose its properties and shape after getting wet. You can insulate an attic with mineral wool in the shortest possible time and without much effort by rolling out and laying the roll, without leaving any cracks or gaps, which is difficult to achieve when laying insulating boards. Insulation from the inside attic space mineral wool - the best option in terms of simplicity and economy

But use should be approached individually and carefully, since basalt fiber sometimes causes allergies.

Laying mineral wool

Advice!

For Russian climatic conditions, it is enough to use mineral wool 20 cm thick. Do not forget to use safety glasses when working with mineral wool. Thermal insulation requires laying a vapor barrier layer.

2. Ecowool. Insulating the attic with ecowool is more preferable than with mineral wool, since this material does not cause allergies. Made from cellulose fibers, ecowool is sold in bags and placed between beams. This insulation does not burn, as it is impregnated with special fire-resistant compounds. Also, when insulating with ecowool, a vapor barrier device is required. One of the disadvantages is the high cost of ecowool insulation.

Insulating the attic with ecowool

3. Glass wool. A type of mineral wool, but with certain characteristics associated with the raw materials from which it is produced. Since the production of glass wool uses waste from glass products, its use generates dust that is harmful to the human body. Laying work must be carried out in special clothing, using glasses and a respirator. Refers to a budget option for insulation. The advantages include high thermal insulation, low cost, lack of toxicity, and non-flammability. Vapor barrier is required.

Glass wool for attic floor insulation

4. Styrofoam. Attic insulation with foam plastic is the most economical way. This material has a low density and is easy to cut with a knife. The foam boards should be laid very tightly, and large cracks should be sealed construction foam. Foam insulation is fireproof and melts at high temperatures, releasing toxic gases.

Foam plastic for insulation of attic floors

5. Foamed polyurethane (penoplex). Refers to modern technological materials.It is produced by applying it with spray devices. The price of polyurethane is quite high and its installation technology is not the simplest. The advantages include the high speed of applying polyurethane to walls and ceilings from inside the attic. The entire floor can be covered with penoplex in a few hours, while achieving a complete absence of gaps, unlike thermal insulation boards.This option is comparable to ecowool insulation. Recommended installation vapor barrier and from the inside.

Penoplex

6. Bulk materials. Old house designs used a mixture of sawdust and dried leaves.Insulation of wooden floorsretained heat in a private home, but had a high fire hazard. Currently, when installing bulk insulation, perlite, slag or expanded clay are used. This thermal insulation is somewhat heavier than the first four types, so you should carefully calculate the structural strength of the floors and ceiling lining. Most often used for floors made of slabs. Expanded clay also works wellbasement insulation.

Insulation of the attic with bulk materials

The correct way to insulate with rolled material and insulation in the form of plates is to lay it on the beams in several layers in a checkerboard pattern. This method of using heat insulators will avoid the formation of cracks.

Insulation of the attic floor of a frame house

Proper insulation of the attic and attic ceiling

Installation technology

Depending on the choice of insulation, the installation method also differs.

Mineral insulation

Cotton wool is laid in three ways: cells, grooves and a continuous layer. The choice depends on the degree of load. The best construction is obtained from a continuous layer. First you need to lay a vapor barrier film. It removes water vapor, which is directed from the room to the attic. The film is laid strictly in accordance with the markings, with an overlap. Wooden structures must be tightly covered with film, otherwise they will rot.

At the second stage, cotton wool is laid. This is a simple procedure; the insulation is cut into strips. When laying, you need to ensure that the insulation does not wrinkle and there are no gaps between the sheets.

Attic floors must be waterproofed. Then lay rough coating, which will subsequently be the basis for finishing.

Polystyrene foam or extruded polystyrene foam

Installing rigid insulation is quite simple. First you need to level the base, remove unevenness and differences in the floor. Lay a cement-sand screed. The sheets are laid between the beams. If no one will live in the attic, then the insulation must be covered with plastic film. And if the floor will be used, then you need to put OSB boards on the foam plastic or fill it with a cement mortar screed.

Sawdust

First, sawdust is mixed with cement and water (10: 1: 1). The base of the attic is filled with this mixture. If it is non-residential, then sawdust is used without a frame, a device for strengthening. But with increased load, it is necessary to strengthen the base, otherwise the sawdust will wrinkle. It is imperative to carry out a calculation and calculate the connection to the wall.

Expanded clay

The disadvantage of insulation is that it is difficult to deliver to the installation site. They cover the floor slabs and the pie. First, the sheathing is installed, then the subfloor is placed on it. The heat insulation is filled in and leveled with a rake. At the end everything is filled with cement mortar. It is better to work with such insulation on the first floor of a private house.

Waterproofing

When the interfloor pie is ready, it is necessary to waterproof the cold attic space. It will help prevent the appearance of leaks and condensation. Most often, the role of waterproofing is performed by foiled polyethylene foam.

It is attached using a stapler with the metalized side facing out, leaving ends 15-20 cm long wrapped on the walls. The joints, as in other cases, are sealed with foil tape.

A sheathing is installed over the entire surface of the resulting structure, which will subsequently serve as the basis for the final coating of the ceiling. Moreover, this is necessary to create an air-thermal floor cushion.

Insulation with bulk materials

For bulk insulation, expanded clay or sawdust is used. Both heat insulators are environmentally friendly natural raw materials that retain heat well.

For backfilling, sheathing is installed in the attic. The bulk layer reaches 250–300 mm. A finishing board or plywood is laid on top.

Video on the topic:

When using expanded clay, it is necessary to carry out additional calculations for the load-bearing capacity of the floors. Expanded clay is not a lightweight insulation material and the ceiling may not withstand the load.

Sawdust, despite its apparent ease of use, requires additional processing and are not poured in pure form, but a special composition is prepared, in which sawdust is only one of the components.

To prepare the solution, the following materials are required:

• 10 parts sawdust;
• 1 part lime;
• 1 part cement;
• 5–10 parts of liquid with an antiseptic.

The choice of heat insulator for the attic and the technology for its installation depends on the required insulation characteristics and financial capabilities.

In any case, even minimal insulation, will protect the building and save on heating costs.

Heating the ceiling of a cool attic

Since the roof of a cool attic serves only the function of protecting against rain, snow and partial wind, special attention should be paid to insulating the soil. Thermal insulating heating is carried out using various thermal insulation materials with mandatory organization of wind protection, especially from the roof side

Thermal coating in two layers with mineral wool cylinders

Installing insulation is usually done directly on the floor of a cool attic.

Of course, if the attic doesn't work. This will save on a layer of waterproofing film, as well as on organizing a complete floor covering.

Read below to learn how to insulate an attic ceiling and what materials can be used for this.

Basic requirements for attic floors

The main quality that any attic floor must have is strength. If we are talking about mansard roof, then the entire structure should not sag or deform under the weight of furniture or equipment located in the attic. There is such a thing as deflection norm. For attic structures it is 1/200 of the entire span. The maximum load per square meter is 105 kilograms. Another equally important parameter of the ceiling is fire safety, which applies to a greater extent to wooden structures. So, fire resistance has the following limits:

1. for concrete or reinforced concrete structures this is 1 hour;
2. for wooden structures (in the absence of additional protection) – five minutes;
3. for wooden flooring on beams, with backfill and plaster - about 45 minutes;
4. for wooden floors with only one plastered surface - 15 minutes.

Vapor barrier functions

When attached to a ceiling or floor structure in a house, a vapor barrier serves not only the purpose stated above. The laying of the material allows us to say the following:

• the ceiling structure, in addition to protection from moisture, receives protection from most types of organic damage (mold, rot, fungus), which require warm and humid conditions to reproduce;
• laying film in the ceiling of a basement, attic or in interfloor structures can significantly increase the service life of wood, reduce the frequency of repairs (significant savings during operation);
• modern materials can create additional protection for the ceiling in the event of a fire and increase its fire resistance, which is important so that people in the house have time to evacuate;
• laying material that has good timing service - a single event, most often replacement of the vapor barrier is not required, the layer does not fail.

Options for installing attic beams depending on its type

Many people ask the question: where is the correct place to install wooden floor beams? Into the walls, onto the walls, or even bring them outside a little? It depends on what type of attic you have and whether you will use it as a living space in the future. The attic is very popular today!

So, here is an economical option that allows you to convert the attic into an attic in the future without any problems. True, very tight:

Therefore, if you have such plans and even now you are not sure whether there is another place in the project for a personal office or a billiard room, then make the walls higher in order to install the floor beams lower.

What will it give? In such an attic there will be much more useful space, less sharp corners and it will be much warmer:

But if in your project the attic was initially planned as a separate and spacious room, as if built on top of the house, then the attic beams need to be installed as strong as in the interfloor ceiling, and also secured to anchors in the reinforced belt:

Here is an excellent step-by-step example of how such attics are built and how strong such a floor should be:

Attic insulation technology

Depending on whether the attic will be habitable, the technology of its insulation also depends. For a warm attic, only the roof is insulated; for a cold attic, only the attic floor is insulated.

Insulation of a residential attic with mineral wool or polystyrene foam

Making a cozy room out of an attic is not that difficult.

If the house has already been built and you don’t want to dismantle the roof, you can do it from the inside:

1. Waterproofing is attached to the rafters, the rolls are rolled out crosswise, starting from the top. This is done so that moisture rolls freely along the outside and does not flow inside onto the insulation through the seams.

All attachment points to the rafters, as well as seams, are taped with butyl rubber tape. Unsealed holes will negate waterproofing measures.
Insulation is being installed. It is easier to use dense basalt or foam slabs that fit tightly between the rafters. It is advisable to additionally fix the soft insulation.

A vapor barrier is rolled out over the insulation. This time they start from the bottom - so that condensed steam does not flow through the seams to the insulation. The film is fixed with a strip nailed to the rafters - it will provide required ventilation gap. All puncture sites and seams are also taped.

After this, you can begin finishing the attic and begin to inhabit it!

After this, you can begin finishing the attic and begin to inhabit it!

A cold attic in a wooden house can be insulated with a minimum of cost and effort using ordinary sawdust. This method will improve the microclimate in the house due to natural ventilation.

To do this, it is important to ensure maximum vapor permeability of the attic floor:

• you need to lay cardboard on the subfloor - just to prevent sawdust from falling through the cracks;
• a layer of sawdust 15-20 cm thick is poured;
• In no case should you cover the sawdust with waterproofing - they should be ventilated without hindrance;
• the floor is laid with a small gap between the sawdust and the boards.

How to properly insulate reinforced concrete attic floors is described in detail in the video:

Floor arrangement

Since the attic floor combines insulating and load-bearing functions, it has a multi-layer structure. Its components, complementing each other, are combined into unified system

• providing strength, load-bearing capacity and durability. If we list all the layers of the attic floor, starting from the attic side, then it looks like this:
• Finish floor. Finish flooring is a decorative floor covering that covers the subfloor of an attic. If the under-roof space is residential, then laminate, treated wood, linoleum, and parquet are used to arrange the finished floor. In an uninhabited attic there may be no finished floor at all.
• Rough floor. A subfloor is a flooring made of boards that is laid over the joists. To install it, use an edged board 4-5 cm thick; in order to save money, it can be replaced with an unedged one.
• Beams. The floor frame consists of strong, thick beams that are installed on ledges in the walls or embedded in them. The beams bear the entire total weight of the structures, so they must have a high load-bearing capacity.
• Ceiling lining. The bottom of the ceiling is sheathed with finishing material, for example, wood or plasterboard, to give an aesthetic appearance to the ceiling of the residential floor.

Note! Thermal insulation and vapor barrier are the same important components of the structure as floor beams or joists, as they protect the wood and insulation from damping out, getting wet and condensation. If you forget about the insulating layers, the ceiling will not last long and will need repairs in 2-3 years.

Attic floor installation

How to properly insulate an attic floor with mineral wool

Mineral wool is a common and modern heat insulator. Available in rolls or slabs (mats). Does not rot or burn, rodents and various kinds Microorganisms are also not scary for her.

Insulating the ceiling of a cold attic with mineral wool begins with laying lining material on the floor. For a budget option, glassine is laid on the floor, but it is more expensive and quality option– flooring made of vapor barrier film. The film is laid with an overlap, and the joints are taped or secured with wooden slats, which are fixed with a construction stapler.

The width of the insulation is selected based on the requirements of thermal engineering standards for each region. Mineral wool is placed between the joists tightly and without gaps. The joints are taped with tape. After the insulation is laid, level boards are simply laid on the joists, thus forming the floor in the attic. This simple solution for creating a floor allows the mineral wool to “breathe” and ventilate normally if it gets wet. To prevent moisture from entering the mineral wool, waterproofing material is laid under the roof.

Mineral wool is laid using personal protective equipment: thick clothing, goggles, gloves, respirator.

Beams for the attic

The attic floor is made using wooden beams after the installation of load-bearing elements is completed. This is the simplest and best way to properly arrange the technical area.

The attic floor structure is usually made of wooden beams. These load-bearing elements have a number of advantages:

• maximum coverage 4.5 m between supports;
• light weight, load on the building, savings on the foundation;
• ease of installation, without the use of lifting equipment or a crane;
• availability of wood as an inexpensive material;
• speed of work, the ability to install an attic floor in a day or two;
• possibility of using any soundproofing materials.

For the manufacture of beams they use conifers wood resistant to moisture, rot, fungus

The cross-section of the beams for the attic floor must correspond to the load, taking into account climatic conditions, thickness of the heat-insulating material. Beam dimensions of 150x200 mm are used if a serious load is expected on the attic floor

For example, it is planned to install a water tank and a transformer. For minimal load, beams of 100x150 mm are used.

The desire to save money and install 50x100 mm beams is not approved. An extremely important element of the house is the attic floor, which provides thermal insulation, sound insulation and reliability of the ceiling. The quality of the overlap guarantees savings in heat and heating costs.

You can calculate the number of wooden beams for the attic floor as follows. Divide the length of the room by 60-100cm (the distance between the beams), add 2 pieces to the resulting value, which will be laid on the walls. Beams should be laid on load-bearing and external walls.

Heating the attic over a reinforced concrete slab

If you need to insulate your attic over reinforced concrete slabs, you can do it in two ways: with or without a box.

The first method is universal, but is most often used for light types of insulation.

In the attic in this case you will see:

1. The vapor barrier is carried out in a cool attic, which should cover the entire layer of insulation, even on the sides.

   Since the vapor barrier should be easy to install on the floor, there is no need to use special materials for this purpose - inexpensive polyethylene film will usually be made.

2. At the top of the film, a wooden stick with a width equal to half the required thickness is placed on the narrow side, which should have a cold attic heater.

   The distance between the rods is usually equal to the width of the cylinder or panel of the selected brand of insulation.

3. Among the boards is an attic heater. If the thickness requires more layers of thermal insulation material, it is laid by overlapping the joints of the previous layer.
4. They are completely identical to the already installed sticks. at the same distance from each other. Between them is a second layer of insulation in the attic.
5. Waterproof cool attic waterproofing installed on top.

   which is secured either with a special adhesive tape or with a thin stick adapted along the box. This level can be lowered if high-quality waterproofing of a cold corrugated roof has already been completed.

6. Sex lanes or traffic bridges are connected through sticks.

Since it is very important that the ceiling under a cold roof is sufficiently insulated to save on heating the house, I recommend using upper system thermal insulation. . This decking will minimize the possibility of cold bridging across the wood studs since most of them will be insulated by the heater

This decking will minimize the possibility of cold bridging across the wood studs since most of them will be insulated by the heater.

Another method of heating a cold attic of reinforced concrete slabs without using boxes is suitable where they are used to insulate solid, wet insulation that can withstand heavy loads without loss of property.

Scheme of a pressure block on a reinforced concrete block

In this case, the first section is in the attic.

The insulation of the attic plates is then completed with a layer of thermal insulation of the designed thickness.

A leveling screed is poured onto it. Estrich is already covering the first floor.

If the insulation of a concrete attic is made of aerated concrete and similar density and properties of materials, you can refuse hydro- and vapor barriers and screeds.

Mineral wool insulation

In order to save heat, the material must be placed between steam and waterproofing films. Vapor barrier protects against moist air masses that form in living spaces near the ceiling, especially at the junction with the walls. The second layer protects the wool from water entering from the roof through microcracks and holes in the roof.

The attic space of a house is insulated most often from the floor rather than from the ceiling of the lower floor. For this purpose, mineral wool is a reliable, inexpensive insulating material with high compression, allowing it to cover the surface of not only the floor, but also beams of various shapes. This insulation is sold in rolls or slabs of different thicknesses.

At the same time, it has the following advantages:

• Budget cost.
• Easy to install.
• Rodents do not grow in such insulation.
• High fire safety of the material.
• Ability to isolate any uneven surface.

At the same time, when working with mineral wool, it is necessary to take protective measures: wear thick clothing, work in goggles and protective gloves, and it is also advisable to use a respirator.

Insulating the attic with mineral wool

Advantages and calculation of beam floors

The entire structure consists of beams and boards, which are called rough. The beams themselves can be load-bearing, located simply next to each other, or fixed in a special way, which is much more reliable. Standard sizes beams - 20-40 centimeters in height and 15 meters long, plus 8-20 centimeters in width.

Unlike reinforced concrete attic floors, wooden ones are installed dry. It is much lighter in weight, so in private construction it is better to use just such an overlap. On the other hand, wooden floors are the least soundproofed, so you will have to spend money on additional measures.

The beams are located at a distance of 60 centimeters to 1.5 meters. Of course, the more often you install them, the greater the load the attic will be able to withstand in the future, but the foundation of the house will also have to endure a greater load.

Light partitions are usually mounted on a wooden attic floor - most often frame ones, to which the attic rafters are directly attached. They need to be installed perpendicular to the beams or edgewise.

But if for some reason the internal walls of the attic have to be placed parallel to the ribs or beams, which is not at all according to the rules, then the structures in these places must be strengthened. Most often, fragments of boards are used as such elements, which are attached perpendicular to the ribs of the floor.

Concrete ceiling

The concrete ceiling is prepared in different ways:

1. If the ceiling has decorative elements, they should be removed and any plaster that can be cleaned should be cleaned.
2. Cracks on the surface must be widened, thoroughly cleaned of dust and prepared.
3. Small gaps can be closed with liquid cement mortar or sealant.

   We heat the attic above the wooden beams

   Large cracks should be sealed with foam. After hardening, the foam is leveled according to the level of the entire surface.

4. The ceiling is covered with an interior base designed for use on concrete surfaces.

   After complete drying, you should start installation work on isolation.

Installation with glue

To heat using this method, all materials will be made in the form of plates of different sizes. This can be basalt wool, expanded polystyrene, expanded polystyrene.

Cement-based mortar and prefabricated foam should be used as glue.

The glue on which the cement is based is prepared according to the recipe on the package.

Pay attention to the specific drying time as it affects the amount of solution required for mixing. . Next, using a brush or blade, the glue is applied to the insulating plates

If you use a toothpick, the grip on the surface will increase.

If you choose precast foam, apply it to the heater with a special gun. The panel with the adhesive attached should be pressed against the ceiling and held for about a minute.

After installing several heater squares, there are holes in the ceiling designed to attach a mushroom to which a spacer nail is later launched. If there are gaps between the plates, they must be carefully filled with foam. The basalt wool heater is installed in a similar way.

This method is carried out under suspended ceilings.

Installation between rails

Thermal insulation with a container is used if plasterboard or lining will be covered by the ceiling.

First you should place marks on the ceiling to give up the lines where the container pieces will be attached.

They should be located at a distance corresponding to the width of the insulation. The wooden frame is attached to the ceiling with screws. The metal profile is fixed with special springs, which allow the hopper to lower to the required distance from the ceiling.

Next you need to install the insulation. The wooden rods are built by the enemy.

The mineral wool itself is well distributed and has, and it can also be grabbed by shelves with pendants.

The foam is installed very carefully as it can interrupt the panel with a good load. . If after installing the heater there are gaps between the box and the foam, they must be filled with pre-assembled foam

If after installing the heater there are gaps between the box and the foam, they should be filled with pre-assembled foam.

After installing the insulation, the ceiling should be covered with vapor barrier film. On wooden frame it is fastened with staples or staplers and on a metal profile using double-sided construction tape.

The stretched vapor barrier film is finally covered with sheets of drywall or backing.

The hybrid plates are attached to guide screws with an inclination of 150 mm. The seams between them are reinforced with mesh and applied to the coating layer. After drying the joints, you can fill the entire surface of the ceiling and then finish the finishing work.

Types of floor structures

There are several types of attic floors with wooden beams. Each of them has its own purpose and its own pros and cons.

Platform: for a cold attic

As for frame houses, the floors in them are recommended using the “platform” system. That is, after installing the walls, beams are laid and a certain platform is created, as it were, and a working foundation for the future floor of the attic at the same time

It is important here not to put unnecessary pressure on fragile walls, so the attic covering will also not be designed for a piano in the corner.

In this case, the beams are installed on a strapping beam, which is used as a power plate:

Rigid board: for uniform shrinkage

But in a house with walls made of logs or timber, according to the rules, a rigid shield is installed as an attic floor, which, when the walls shrink, will smoothly lower with them, and always evenly.

Economy flooring: to save time

Prefabricated wooden floors should be highlighted as a separate type of attic floors. Their main feature is the use of special fasteners, which are made of galvanized steel. Their thickness and quality are calculated depending on the level of future loads on the floor.

Standard attic floors on beams with beams and wooden joists appeared at the end of the 20th century, and after them floors made of wide boards became more fashionable.

Ready-made trusses: for a residential attic

Today, special ready-made companies for arranging attic floors are also in fashion. In fact, this is not a new thing in the construction market; such companies appeared at the end of the 16th century and found their rebirth at the end of the 20th century. Canadian companies that were involved in construction developed special programs for calculating such companies and their exact shapes with assembly lines.

In our country, new types of wooden floors are beginning to appear, which until now were popular only abroad. These are light wooden floors. They are relevant for private construction, when a fairly light wooden frame is used as a system.

The essence of the overlap is that “ribs” are installed every 30-60 centimeters, and they are covered with sheathing. Wooden beams with a height of about 20 and 28 centimeters, a thickness of 45 centimeters, and a length of up to 5 meters are taken as “ribs”. They are made from natural wood and connected with special bundles of boards, covered with chipboard or fiberboard sheathing.

Therefore, we highlight quick and simple installation as the main advantages of a ribbed attic floor. Of the minuses: the need for treatment with a fire retardant, less strength and low sound insulation properties. And, of course, such boards are more sensitive to sudden fluctuations in humidity and temperature. And also, if a fungus or some insect decides to eat such a ceiling in a few years, it will eat it much faster than thick beams.

From below, this structure is covered with a suspended ceiling made of plasterboard slabs. Mineral wool is placed between the ribs on top. It is this that will provide fire resistance and sound insulation to the entire wooden floor.

Ribbed attic floors are much cheaper than beam floors - this is quite reasonable and rational if you do not insulate a non-residential premises and make a residential attic out of it. Then you don’t have to worry about the load-bearing capacity of such a foundation. The only negative is that the beams are more common for Russian houses, and the ribbed ceiling is almost the same appearance from monolithic. Therefore, in Russian houses, ribbed beam attic floors are more often installed.

The timber for constructing such an attic floor needs to be taken rectangular shape, and strictly, and not in a diamond shape. And be sure, when buying such timber, take with you the most common school ruler, because it often happens that many people are going to build a floor from 15x15 cm timber, but in the end they are built from 14x14 cm timber. And then, on your site, be sure to prepare a place for storage such timber and its processing.

By the way, today many even install ordinary timber in a wooden floor on its edge. The fact is that even a ruler, no matter what material it is made of, easily bends along its entire length, but if you place it edgewise, it will be almost impossible to bend it:

And on rough floor Lay the finished floor out of boards and install a suspended ceiling underneath. But often the wooden floor of the attic is left without additional finishing on purpose, in view of the interior design concept, but then all its details are done very carefully and even with a decorative slope:

The suspended ceiling itself imparts a certain rigidity to the ribbed ceiling.

Attic device

An attic is a room limited by the roof slopes and the ceiling of the residential floor. This room can be used as a seasonal storage place or for the purpose of organizing additional living space. Depending on the nature of use, attics of residential buildings are divided into the following types:

• Residential. The livable attic of a home is called a loft and can serve as an additional bedroom, living room, bedroom or office. To use the attic as a living space, it must have a ceiling height of at least 2.2 meters, natural lighting, ventilation, and thermal insulation of the slopes.
• Non-residential. A non-residential attic can be used to install any technical equipment or organize storage of things. In this case, the height of the attic space may be less than 2 meters, there may be no natural light, and the thermal insulation of the slope is replaced by insulation of the attic floor.

Important! When carrying out repairs or reconstruction of a house, it is important to immediately decide how the attic will be used in order to correctly calculate and design the attic floors. The type, material, distance between the beams will depend on this, which will ensure sufficient strength and load-bearing capacity of the structure

Attic insulation

Insulation technology

Wooden interfloor ceilings are the most common option in individual housing construction. Their design is the same in both a wooden and aerated concrete house. It is a plane with stiffening ribs, between which the material used for insulation is placed. The house floor plan is shown in the figure below ( rice. 6).

When installing attic and basement floors, the beams are usually left uncovered on one side, which makes adjustments to the technology of the work performed - to insulate the floor with bulk and slab materials (expanded clay, mineral wool), an additional raised floor is required between the beams. But you are free to choose the type of material yourself, based on knowledge of their properties.

Floor insulation

For these works it is best to use foamed polyethylene. All work is carried out underground. A piece is cut from the roll equal to the length of the gap between the beams. It is most convenient to secure it with a construction stapler, using staples with a height equal to two thicknesses of the material. It is not advisable to use foil material - there is no source of radiant energy in the underground.

Insulation of interfloor ceilings

The insulation between floors should also play a role in sound insulation, so the use of foam plastics for this purpose is undesirable. The best option– mineral wool or expanded clay .

Expanded clay backfill ( Fig.7) may be too heavy. To prevent it from tearing off the ceiling material in the lower room, slats with a section of 2 by 2 cm are nailed onto the beams. Boards are laid on them, which will serve as the basis for it. Waterproofing is not required, but geotextiles (non-woven material) must be laid on top of the expanded clay to prevent dust from entering the room.

Mineral wool ( Fig.8) requires waterproofing both above and below (the air coming from the lower floor is saturated with moisture). As original solution waterproofing, allowing you to combine business with pleasure, between the beams, directly on the ceiling boards of the lower floor, foil foamed polyethylene is laid (foil down). Mineral wool can be placed directly on it if it is a roll material. The slab is denser and heavier. Therefore, you need to do the same as in the case of expanded clay - nail down the skull blocks and lay the plank sheathing on it. Then between the penofol layer and the ceiling there will be space necessary for the foil to reflect radiant energy. Without this condition, it will not work.

The mineral wool is covered with a film on top. It plays the role of waterproofing and also prevents mechanical particles (fiberglass) and volatile substances from impregnation. The film can be either ordinary or membrane, allowing steam to pass in one direction. It is laid with the waterproof side up, towards the floor ( Fig.9).

Insulation of the attic floor

Insulation of the attic interfloor over wooden beams crowns all the work. The amount of fuel spent on heating largely depends on its quality - more than half of all heat leaves through these gates.

If the attic space is not heated and the floor is non-residential, then sawdust can also be used for thermal insulation ( Fig.10) – a large open area guarantees their complete drying. But it is better to use this material as an additional one, and the main one will be foam ( Fig.11).

The first layer of foil polyethylene is laid. Foam plastic is lightweight, so there is no need to nail the cranial bars to the beams and there is no need to install additional lathing. Foam plastic slabs are placed on top of them, the joints - including those with walls - are filled with polyurethane foam, resulting in the formation of a continuous thermal insulation coating without seams. If cheap packaging foam is used (balls are visible when scrapped), then a layer of sawdust is poured on top of it, which not only increases the thermal insulation properties, but also protects the polystyrene foam from the destructive effects sunlight. Extruded construction material - polyhedral bubbles are visible on its cut - is more resistant, but it won’t hurt to sprinkle it with sawdust.

In the attic, plank ladders must be installed on top of the insulation so that you can walk without destroying the structure or trampling the heat-insulating layer.

The proposed technology for insulating floors has been tested in practice and gives good results.

Are you insulating your house for winter and don’t know how to insulate the attic floor using wooden load-bearing beams? Having gained experience in this matter, I will accurately convey the technical aspects of thermal insulation, and also describe the procedure for carrying out the work step by step.

Why insulate an attic?

We must not forget that a significant part of heat loss occurs through the roof. Therefore, when constructing buildings with cold attics, it is very important to pay attention to proper thermal insulation of the ceiling between the heated room and the attic.

Below I will try to explain in an accessible language how attic insulation affects the internal microclimate and total losses heat in the house:

1. Purpose of the attic. Any unused attic under a sloping roof is, in fact, a buffer technical floor between the street and the living space. Its purpose is to smooth out significant changes in air temperature inside the house and outside;
2. Temperature conditions. At any time of the year, during the day the air temperature inside the attic will be several degrees higher than outside. Thus, in winter there will almost always be negative temperatures in the attic, and on sunny summer days there will be intense heat;
3. Heat losses in winter. When the temperature of any substance increases, its density always decreases. Therefore, in heated rooms, heated air from household heating appliances always rises up to the ceiling. If the ceiling has insufficient thermal insulation, then during the cold season, all the heat from the room will go outside through the attic;

1. Excess heat in summer. On hot summer days this process will occur in reverse. The air in the attic will become very hot from the hot roof in the sun, and then transfer its heat through the uninsulated ceiling into the apartment.
2. Reverse air circulation. After touching an uninsulated ceiling, the heated air quickly cools down, and due to the increase in density, it sharply sinks down. Indoors, this leads to excessive reverse air circulation and the constant formation of drafts, which have an adverse effect on the health of residents;
3. High humidity. When heated, humid air comes into contact with a cold, uninsulated ceiling, small drops of condensation may form under the ceiling. This will lead to an increase in air humidity in the house, and will also contribute to the appearance and development of mold on the walls and ceiling;

1. Economic factor. Confirmed heat loss through an uninsulated roof is at least 20-30%. It means that proper insulation attic floors on wooden beams will save up to 30% of fuel during each heating season. Air conditioning in summer will also require lower costs;
2. Damage from a “warm” attic. Among other things, penetration warm air to an uninhabited attic, from time to time, can lead to unpleasant consequences:

• As warm and cold air mixes, condensation will begin to form in the attic. Drops of water will settle on all surfaces, which will lead to rotting and destruction of the wooden supporting structures of the roof;
• From the warmth of the attic, the snow masses on the roof slopes will gradually begin to melt. Thawed water will freeze as it flows down. This can lead to the formation of large icicles along the edges of the roof, as well as freezing of rain gutters and downspouts.

All the factors described are typical not only for residential buildings. They should be taken into account when designing and constructing any outbuildings on the site where the heating system will be used (for example, a garage, bathhouse, barn, etc.).

Stage 1: Selecting insulation

When choosing materials for ceiling insulation, you should be guided by several criteria. In addition to low thermal conductivity, attic insulation must have the following qualities:

• Moisture resistance and mechanical strength. The material should not be deformed or destroyed under the influence of mechanical load, and should not change its properties in the event of direct contact with water;
• Heat resistance. The insulation must be absolutely non-flammable and should not be destroyed under the influence of high or low temperatures;

• Light weight. In order not to create additional load on the load-bearing structures of the building, the thermal insulation of the attic floor should be quite light, so you need to choose insulation with a low specific gravity;
• Vapor permeability. To ensure normal temperature and humidity conditions in residential premises, all finishing and Construction Materials must allow air and water vapor to pass freely;
• Environmental Safety. Insulation for residential buildings must be hypoallergenic and chemically neutral. It should not contain harmful volatile compounds or toxic substances;
• Lack of organic matter. I recommend using exclusively mineral or polymer based materials. They do not contain organic substances, therefore they are not susceptible to mold, and are not suitable for food for small rodents and pests.

Taking into account all these factors, several types of thermal insulation materials can be used to insulate attic floors:

1. Mineral wool. Produced in the form of rolls or rigid mats, from intertwined frozen fibers of molten sedimentary rocks. Mineral basalt wool is characterized by all of the above qualities, so it can be considered the most suitable material. Below I will give some recommendations for its use:

• Basalt wool itself is very soft. To prevent it from being pressed or dented while walking, plank flooring should be laid on top of it in the attic;
• When choosing insulation, I advise you to give preference to rigid slabs that are covered on one side with aluminum foil;
• They need to be mounted with aluminum foil inside the room. It simultaneously reflects heat and acts as a vapor barrier layer.

1. Glass wool. It has a similar manufacturing technology, only molten glass is used as the raw material for its production. I do not recommend using this material for insulating residential buildings for the following reasons:

• Glass fibers are more fragile, so they can break under load;
• The price of glass wool is much lower, but after creasing or getting wet, it partially loses its heat-insulating properties;
• Small particles of glass penetrate deeply into a person's skin and cause severe irritation.

1. Expanded clay. This bulk insulation is produced in the form of small round pellets of light brown or red color. Expanded clay balls are formed as a result of sintering special varieties of red clay under conditions high temperature.

Expanded clay has the following characteristic qualities:

• The internal structure of the material has many closed pores, so it has low thermal conductivity;
• Each pellet is covered on the outside with a dense glassy layer of baked clay, so moisture practically does not penetrate inside it;
• Small crumbly expanded clay pellets freely fill the entire volume, so they are convenient to use for insulating hidden cavities and hard to reach places in building structures;
• Thanks to its mineral base, this material does not burn at all, does not emit harmful substances, is not susceptible to mold, and is not suitable for rodent food.

1. Styrofoam. This polymer thermal insulation material is made by hot molding from small round granules of polystyrene foam. It is usually produced in sheets measuring 1000x1000 mm, which can be from 10 to 150 mm thick. The following features are characteristic of polystyrene foam:

• Of all existing types of insulation, it has the lowest thermal conductivity;
• The foam contains no organic substances, so it is absolutely not afraid of water, does not rot and does not contribute to the formation of mold;
• By itself, polystyrene foam does not burn and does not support combustion, however, when exposed to high temperatures, it can emit toxic gases and acrid thick smoke;
• Due to the polymer base and closed porous structure, foam sheets do not allow air and water vapor to pass through. For this reason, it is not very good to use for insulating living rooms and rooms with high humidity air.

1. Extruded polystyrene foam Abbreviated as EPPS. It has the same composition as polystyrene foam, but is made by hot extrusion from a molten mass of polystyrene foam. The technical characteristics of these two materials are also very similar, however, EPS still has some differences:

• Expanded polystyrene has a porous, uniform structure and a higher specific density;
• Due to this, it has higher thermal conductivity, but at the same time is more durable, and therefore is able to bear higher weight loads;
• For this reason, I recommend using it for insulating unheated attics that will be used for storing seasonal items or household equipment.

1. Foil polyethylene foam. It is also called “Penofol” in another way. This roll material consists of thick polyethylene foam film, which is covered on one or both sides with a thin layer of aluminum foil. I recommend using it in combination with other types of insulation, because by itself it has specific properties:

• The porous structure of polyethylene foam provides low coefficient heat transfer, so it serves as additional insulation;
• Polyethylene film does not allow air, drops of moisture and water vapor to pass through at all, so Penofol can be used as waterproofing;
• Mirror aluminum foil reflects infrared heat waves well. In other words, it does not allow radiant heat to pass through itself, and returns it back to the room.

1. Wood sawdust. This one is cheap and available material, is still often used to insulate ceilings in bathhouses, heated barns or small country houses. It is applied to the wooden floor from the attic side, in the form of a homogeneous thick mixture of sawdust with a liquid clay solution. Despite the seeming primitiveness of this method, it has its advantages and disadvantages:

• Sawdust or small shavings can be bought inexpensively, or even taken for free, at almost any large sawmill;
• There can be no problems with clay either, so such insulation is easy to prepare with your own hands in the required quantity at any time;
• The mixture of sawdust and clay has a low specific gravity, and after hardening it becomes quite hard. Therefore, it does not exert a significant load on the load-bearing beams, and allows you to walk on it with your feet;
• Due to the mineral components, such a coating is permeable to air and steam, however, due to sawdust, mold may form on it, or mice may chew on it.

All mineral-based thermal insulation materials, to one degree or another, are capable of allowing water vapor and air to pass through. To protect such insulation from the formation of condensation or moisture penetration from the outside, they must be installed using a vapor-permeable waterproof membrane.

Stage 2: Preparation of materials and tools

In addition to insulation, for the work you will need lumber, waterproofing, as well as the usual set of carpentry and carpentry tools:

1. Two hammers: one medium, weighing 200-300 grams, and one heavy, weighing 800-1200 grams;
2. Longitudinal and transverse hacksaw for wood. Instead of a cross saw, it is more convenient to use an electric cutting machine;
3. A carpenter's plane, a large wooden mallet and a set of chisels;
4. As for electric tools, you need to have an ordinary household drill, and it is advisable to have a cordless screwdriver with a set of replaceable attachments;

1. For fastening roll materials(waterproofing, vapor barrier), I recommend using a construction or furniture stapler with a set of metal staples;
2. You will also need a straight metal ruler, a tape measure 3-5 meters long, a building level and a simple rope plumb line;
3. To work near the ceiling, it is most convenient to use a folding stepladder. If you don’t have one, you can use a high, strong table or homemade trestle made from scrap boards for this purpose;
4. From lumber you will need wooden blocks with a cross-section of 62x62 mm, and planed edged boards with a thickness of 25-30 mm;

1. As a waterproofing layer, you can use a film of foamed polyethylene and a vapor-permeable waterproof membrane;
2. To seal the joints of the panels, you will need metallized aluminum tape, which is usually used in ventilation systems;
3. Each homeowner chooses materials for finishing the ceiling at his own discretion. This could be lining board, drywall, laminated OSB or plywood, or other finishing materials;

If you plan to use mineral or glass wool for insulation, then I recommend purchasing a special protective suit that is designed to work with these materials. Otherwise, severe irritation may occur on exposed areas of the skin from small glass fibers.

Stage 3: Filing the rough ceiling

During construction attic floor or erecting a sloping roof, you can do without expensive and heavy concrete floor slabs. Instead, the entire load from the roof is carried by wooden load-bearing beams made of logs or timber, with a cross-section of at least 120x120 mm. They are usually laid on top of two main exterior walls, perpendicular to the long side of the house.

Such beams serve as a supporting structure for the ceiling itself. top floor, and for the floor of the attic. The same beams will also be used for installing insulation between the residential building and the attic. This type of ceiling is called hemmed, because both the rough and the finished ceiling are hemmed from below to the load-bearing beams.

Before insulating the attic floor, you need to mount the rough ceiling:

Illustration	Description of work
	Installation of a rough ceiling. To hem the rough ceiling, you should use dry edged boards 25 mm thick, or plywood sheets 10 mm thick or more.
	Hemming boards. They must be secured to the lower plane of the load-bearing beams and beams around the perimeter of the room. Hemming boards must be fastened without gaps or cracks, close to each other. For fastening, use galvanized self-tapping screws 5-6 mm.
	Waterproofing. When the entire rough ceiling is hemmed to the load-bearing beams, panels of foiled polyethylene foam need to be secured to it from below. This can be done using a stapler. "Penofol" will perform the functions of heat and waterproofing. It should always be placed with a foil layer towards the warm room.
	Sealing joints. To prevent moist air from the room from entering the insulation, the ends of the polyethylene film must be wrapped on the walls by 150-200 mm. The joints between the panels must be glued with metallized tape on an aluminum base.
	Attaching the sheathing. From below, across the entire area of ​​the rough ceiling, nail a counter batten made of wooden slats thickness 15-22 mm. It is needed in order to provide a ventilation air gap between Penofol and the finished ceiling. The distance between the slats should be about 400-600 mm. In the future, a finishing ceiling covering will be attached to them from below.

Before starting work, all wooden structural elements must be treated with antiseptic and fire-retardant impregnations. Antiseptics are needed to protect wood from rotting and mold development. Fire retardants give dry wood fire retardant properties.

Stage 4: Installation of thermal insulation

After filing the rough ceiling, the transverse load-bearing beams will be on the side of the attic. Insulation will be laid in between them.

Depending on the thermal insulation materials used, further installation technology may have some differences. Therefore, below I will briefly discuss the use of the most common types of insulation.

1. Laying mineral wool. Mineral insulation materials, when wet, partially lose their properties. To prevent condensation from forming in the mineral wool, the entire thermal insulation layer of the cold attic floor must be permeable to air and water vapor:

Illustration	Description of work
	Vapor barrier. First, you need to lay a vapor-permeable waterproofing membrane on top of the rough ceiling. Its peculiarity is that it freely allows water vapor molecules to pass through, but does not allow bound liquid water molecules to pass through. The membrane panels must overlap each other by at least 150 mm;
	Installation of insulation. Place sheets or rolls of mineral wool in the spaces between the wooden beams. If it is very soft, then it does not need to be squeezed or squeezed much. Lay another layer of vapor-permeable membrane on top of the mineral wool. To prevent it from moving over time, it must be stapled to the beams and walls, throughout the entire area and along the perimeter of the attic.

1. Installation of foam plastic. Polymer-based insulation does not have breathable properties, so it does not allow air and moisture to pass through. There is no point in using a waterproof membrane in this case:

Illustration	Description of work
	Laying foam. Panels of foam or extruded polystyrene foam can be laid between cross beams, right on top of the rough ceiling boards. I advise laying them in two layers, so that the joints of the sheets are located in different places and do not intersect with each other.
	Polyurethane foam. To prevent the insulation sheets from moving to the sides, they can be glued to the sub-ceiling using a special glue for polystyrene foam or polyurethane foam. Thus, it is necessary to fill the entire area of ​​the attic floor with insulation. If there are gaps and cracks between the sheets of foam plastic, then they must also be blown out from a balloon with polyurethane foam.

1. Clay with wood shavings. Insulating the attic floor with a sawdust-clay mixture does not require any additional materials, and is also quite simple:

Illustration	Description of work
	Preparation of the solution. To make the sawdust-clay solution plastic, the clay must be soaked in water 2-3 days before starting work. To prepare the solution, you need to take 3-4 volume parts of sawdust, and 1-2 parts of dry red clay without large solid particles and foreign impurities. Mix the soaked clay with water until a liquid, flowing solution is obtained; Add sawdust to the resulting mixture and mix thoroughly until smooth. To protect against mold formation, a small amount of copper sulfate can be added to the prepared solution.
	Laying sawdust-clay mixture. Lightly moisten the supporting beams and boards of the rough ceiling with liquid clay milk. After this, fill all the gaps between the beams with sawdust-clay mortar and leave for several days until completely dry.

1. Expanded clay backfill. I want to say right away that expanded clay does not have very good heat-insulating properties, therefore, in individual construction, such insulation of floors is rarely used. At the same time, it is considered inexpensive, unpretentious and the easiest to install:

Illustration	Description of work
	Preparatory work. Expanded clay pellets do not absorb moisture, and therefore are not afraid of water ingress or condensation. Therefore, they can be used both with and without a waterproof membrane. To prevent condensation from seeping through the ceiling into the house, I still recommend laying a waterproofing membrane under the pellets;
	Filling of pellets. Expanded clay pellets should be poured on top of the rough ceiling boards and evenly distributed in a thick layer over the entire area of ​​the attic. No covering material is required on top of expanded clay.

To prevent expanded clay pellets from bunching up and spreading throughout the attic, a retaining plastic geogrid is used. It needs to be stretched in the spaces between the load-bearing beams, and then expanded clay should be poured into its cells.

Stage 5: Arrangement of the floor in the attic

Many residents use the cold attic in their private home as a storage room for storing long items, seasonal items and all sorts of things. unnecessary trash. In order for a person to safely walk on the insulated floor, a durable subfloor must be installed in the attic.

The choice of material for installing the floor in the attic will depend on the type of insulation used:

Illustration	Features of application
	Mineral wool and polystyrene foam. These materials themselves are very soft. To prevent them from being destroyed or wrinkled while walking, the top floor covering must be sufficiently rigid. In such cases, OSB or plywood sheets with a thickness of at least 18 mm should be laid on the load-bearing beams. You can also use unplaned edged boards with a thickness of 25 or 30 mm.
	Extruded polystyrene. It has higher rigidity, so it can withstand significant loads. To prevent it from being pressed when walking, it is enough to put a light flooring of thin boards or plywood 5-9 mm thick on top of it.
	Under the weight of a person, they will crawl in different directions. To prevent this from happening, you need to lay 10 mm thick plywood sheets or light wooden ladders made of boards on top of the beam floor.
	Sawdust-clay insulation. After the solution hardens, it becomes hard like cement. A person can move freely on its surface, even without installing additional flooring.

When installing rough flooring in the attic, you should always leave gaps 15-20 mm wide between boards or sheets of plywood. This is done so that moisture and condensation can freely evaporate from the insulation.

Conclusion

Using this algorithm of work, you can easily insulate the ceiling in the attic in own home. More visual information on each method of insulation can be viewed in the attached video in this article, and I suggest leaving all your comments and questions in the comment form.