How to insulate the draft floor of a wooden house. Floor insulation in a wooden house from below: materials and installation technology. How to insulate the floor in a wooden house: the choice of material

Kirill Sysoev

Calloused hands do not know boredom!

Content

One of the problems of living in a private house made of wood is a cold floor. The fact is that air currents of low temperature go down, coolness also comes from the earth. To make the home cozy, warm and comfortable, to protect it from freezing will help the insulation of the floor covering, which is performed using a variety of materials.

How to insulate the floor in a wooden house from below

It is known that the house is the fortress of every person, so it should always feel cozy and warm. One of the ways to transform the living space is to insulate the floor in a wooden house from below. To get a positive result, you should carefully familiarize yourself with the range of products for insulation, find out the features, choose the best option and complete the installation.

The installation of a thermal insulation layer is distinguished by several specific nuances:

Two-layer floor insulation is required in a wooden house from below. It is necessary to reduce the loss of heat leaving through the draft bottom. As a rule, the floor is made of ordinary boards that fit together. The surface will suffer from strong exposure to moisture and low temperatures from the ground, so building materials must be treated with special equipment in advance.
Given the fact that wood absorbs liquid well, waterproofing will be needed. Before starting to insulate a wooden floor, it is recommended to lay a one-sided fiber.
Products for floor insulation in a wooden house from below should not change their characteristics when in contact with wood.

What insulation is better for the floor in a wooden house

Very often, consumers think about what material is more profitable to use to insulate a cold floor in a wooden house from below. The choice of insulation depends on such factors: the size of the room, the type of surface, the type of wood, the climate, the price. It should be said right away that expensive finishing material is not always the best in quality and may simply not be suitable for a particular building. To make the right choice, it is recommended to find out what kind of insulating floor materials are, to study their characteristics, advantages.

Materials for thermal insulation

The range of modern thermal insulation is very wide. Products may differ in dimensions, characteristics, installation technologies, and so on. Insulation of floors in a wooden house is often carried out with such building materials: mineral wool, expanded clay, penofol, polystyrene foam (expanded polystyrene), polyurethane foam, sawdust, penoplex. The choice of thermal insulation layer depends on the individual preferences of the owner of the building and the characteristics of the flooring. How to insulate the floor in a wooden house during the construction or repair of a dwelling?

Mineral wool

Cold wood flooring is often insulated with mineral wool. This type of seal is available as elastic mats or durable panels. The material must be laid in a single layer. The main advantages of mineral wool:

high sound and heat insulation;
long term of practical use;
resistance to fire and high humidity;
affordable cost;
environmental friendliness;
such a heater is resistant to damage: mechanical and chemical influences.

polyurethane foam

The ideal sealant for a wooden floor, the pores of which are closed with air and gas for insulation, is polyurethane foam. This cellular material has a small mass, but retains heat well. Such a heater is most resistant to the formation of fungus, mold, is not afraid of decay, and is not affected by acids. Polyurethane foam is applied using special equipment and has good adhesion (adhesion to the surface). Thanks to the use of this type of thermal insulation, it is possible to insulate the floor of any shape without the formation of joints.

Styrofoam

Thermal insulation of floors using polystyrene (expanded polystyrene) has a large number of advantages. The structure of the material provides a low level of vapor permeability and thermal conductivity, fire resistance, reliability, resistance to chemical and biological factors. Expanded polystyrene has a long service life and retains its characteristics for a long time. The main disadvantage is that the sealant absorbs a certain amount of liquid, which may affect some properties.

Penoplex

The wooden floor is also insulated with foam plastic - a very light homogeneous polymer material that does not exert a load on the base of the building. It is obtained by extrusion - forcing molten raw materials through the molding recess of the extruder (special equipment). Penoplex is very durable, resistant to low temperatures, durable, characterized by minimal moisture absorption and combustion.

Expanded clay

Thermal insulation of a wooden floor can be carried out using expanded clay - loose, porous products, which consist of small round balls. Insulation is produced by burning slate or clay in a special furnace. Expanded clay to preserve the heat of a wood floor is a durable and environmentally friendly material. It has high rates of sound insulation, fire resistance, frost resistance. There is one significant disadvantage: after a certain period of time, expanded clay is compacted under the weight of its own weight and loses the quality of thermal insulation.

Penofol

Roll-type insulation for a wooden floor, which is made of polyethylene foam, which is covered with aluminum foil on top, is penofol. Such a sealant is not very thick (3-10 mm), but it conducts heat well and does not need additional vapor barrier. Due to its composition, penofol has several disadvantages: rust can “eat” the foil, and polyethylene loses strength over time.

Installation technology

A reliable and effective option for laying insulation for wooden flooring from below is installation along logs - transverse boards (beams) on which the flooring is located.

First, logs are attached to the brick foundation, the distance between which should be 1-1.2 meters (as in the photo).
Chipboard or thick plywood is mounted on the bars from below using self-tapping screws. This is necessary for laying thermal insulation.
Insulating material is laid out on the surface between the lags. The thickness of this layer of thermal insulation can be varied, so you need to focus on the dimensions of the transverse boards (lag).
Waterproofing (for example, a plastic film) is laid on top of the sealant. This type of material is not always used, because some types of insulation are themselves resistant to moisture.
The final stage of installation is the installation of elements of the old or new wooden floor covering on the ground floor.

Wooden floors more often than others, especially in recent times, are used in the construction of suburban private houses and cottages. Floors are constructed both on wooden beams and on reinforced concrete floors.

The thermal conductivity of wood is much lower than that of stone or concrete, making it warmer to the touch. Nevertheless, it is very often necessary to insulate the wooden floor, especially on the first floors of buildings.

Types of wooden floors

The method of insulation largely depends on the design of the wooden floor. Three types can be distinguished:

boardwalks;
plywood;
parquet.

Plank floors are made by laying boards on logs - wooden blocks mounted at a certain distance. Such designs are very often made in wooden houses. Plank floors can immediately form the top finish, or they can be the basis for some other decorative material. In the second case, such floors are called black floors.

In order for the boards in the intervals between the lags not to sag from the weight of people or any objects standing on the floor, they are connected to each other when laying. To do this, the boards are grooved, creating a groove on one edge, and a spike on the other. When installing the floor, the boards are rallied, the spikes enter the grooves, making up a massive wooden shield lying on the logs.

Plywood floors are used mainly as draft floors. Plywood is also laid on the logs and fixed. Any coating can be mounted on top of plywood: linoleum, parquet, laminate.

Parquet floors are a set of hardwood slabs that are stacked in a special order, forming a decorative pattern. Parquet can be laid both on a rough wooden floor and on a concrete floor.

Depending on the type of floor, the methods of insulation will vary. To choose the right one, you need to take into account the purpose of the building - is it a residential house or a cottage. Much also depends on the supporting structures, the methods of insulation in wooden, brick or aerated concrete houses may vary. It is also necessary to take into account the presence or absence of a basement under the floor.

materials

There are many ways to protect the interior of the house from the cold, but first of all, you need to insulate the floor and roof, since it is through these structural elements that the main heat loss occurs. Only when these structures are well protected from the cold does it make sense to insulate a wooden house from the inside or outside.

It is advisable to insulate the floors of the second and subsequent floors if they are arranged on concrete floors.

For insulation, various materials are used that have a low coefficient of thermal conductivity:

polystyrene or foam plastic;
polyurethane foam;
mineral or glass wool;
penofol;
sawdust.

Each has its own advantages, and in most cases the choice depends on the availability of a particular material and the personal preferences of the homeowner. The thickness of the heat insulator depends on the climate in which the wooden house is located, on the location in relation to the ground level, as well as on the manufacturer's recommendations.

Thermoplastics

Note! For comparison: in terms of thermal efficiency, foam plastic 5 cm thick is equivalent to brickwork 75 cm thick.

Such materials are convenient to use, as they are produced in the form of sheets of various thicknesses. Transporting them to the construction site is not a hassle. They are very light and durable. You can cut foam or foam plastic with an ordinary clerical knife. When insulating the surface, they can seal the resulting gaps at the joints with ordinary mounting foam. Adhesion with insulation is very good.

Polyurethane foam is a material that is more commonly seen in everyday life as foam rubber mats. In construction, such mats are not used, and polyurethane foam is applied to the surface by spraying. Later, in the process of hardening and polymerization, it foams, solidifying. As a result, polyurethane foam forms a durable, waterproof, airtight warm coat for building structures.

Mineral wool

Various building wool has been used as a heater for a very long time. Currently, glass wool, mineral or basalt wool are most often used.

In terms of type and production technology, they are very similar to each other, differing from each other only in the raw materials used. To obtain them, the raw material is heated, melted using special equipment, and then drawn into threads. Later, when these fibers solidify, looms, vaguely reminiscent of weaving machines, knit a bulky mass with a low density from them.

Such heaters are produced in the form of rectangular mats of various thicknesses or in the form of rolls.

Penofol

Penofol are called thin plates or sheets of polyethylene foam. Their thickness can be from 3 mm to 10 mm. In terms of thermal insulation qualities, this material is comparable to polystyrene foam or foam plastic, but it is more convenient for them to work due to the fact that it is flexible. Penofol is produced and supplied for sale and to construction sites in rolls 0.5 meters and 1 meter wide.

Insulation is produced in three versions - foiled on one side, on both sides, or foiled on one side and with an adhesive layer applied on the other. The latter option is most preferable, since the installation of such a heater takes very little time. It is enough to cut out the necessary blank from the sheet and, having separated the protective film from the adhesive layer, attach it to a wooden surface and press it briefly.

Sawdust

Sawdust has traditionally been used as insulation, as it is a by-product of any sawmill industry, and its origin has always accompanied the manufacture of lumber. For a very long time, it was sawdust that was used to insulate wooden floors, falling asleep in layers between the lags.

The mass of sawdust, if it is not subject to getting wet, can lie in a closed space for years and not cake. At the same time, the low density of such a heater is maintained, which provides excellent thermal insulation properties. The disadvantage of such insulation is that the sawdust very quickly cakes and even begins to rot, as soon as they are wetted a little. To prevent rotting of sawdust and damage by various woodworms, they are treated with a solution of potassium permanganate or sawdust is mixed with lime.

Plank and plywood floors on logs

The ideal option is one in which floor insulation is carried out at the stage of building construction. In this case, you can foresee all the nuances and avoid mistakes, unnecessary time and material waste. The maximum effect of insulation will be obtained only if the level of the wooden floor of the first floor is located at a distance of at least 25-30 cm from the ground level planned around the building.

The floors in wooden houses are arranged along the beams, which are laid on the same level with the first crown of the log house. Logs are laid on top of the beams, and already along them - a plank or plywood coating. When insulating a wooden floor during construction, you can place heat-insulating material between the beams. To do this, cranial bars are nailed along their entire length from below, on which plank or plywood flooring is supported. Between two adjacent beams a space is formed that can be filled with insulation.

Note! Before laying the insulation, you need to lay a layer of vapor barrier.

At the same time, it must be oriented so that water vapor from the insulation comes out into the underground. They are removed from the underground space through special ventilation holes, which must be provided in the foundation. During the winter, such vents are usually closed to keep cold air out of the space under the floor.

With a basement

If the basement of the house is provided under the first floor, there may be no ventilation holes in the foundation. In this case, ventilation of the basement must be provided. Often it is performed by leading a ventilation pipe up above the roof and installing it along one of the walls of the house.

Additional vapor barrier

After laying the insulation, it is necessary to mount another layer of vapor barrier, the vapor permeability coefficient of which will be several times less than that of the lower layer. To do this, you can use the most common plastic film or any rolled foil materials. In this case, the foil must be placed towards the internal volume of the room, then it will have a reflective effect for heat. Logs are laid along the top layer of the vapor barrier, and boards or plywood are mounted.

The thickness of the lag will ensure that there is an obligatory air gap between the top layer of the vapor barrier and the floor covering. Ventilation in this gap can be provided by drilling several holes in the floor at the corners of the room or using special slotted skirting boards.

In the case of an old building

If it is necessary to produce insulation in already built buildings, the method described above is not suitable, since it is irrational to open existing wooden floors. In this case, if the height of the floor allows, the old coating can be used as a subfloor. On it you need to lay logs with insulation and on top of them - a new plank flooring. Just as in accordance with the method described above, a layer of vapor barrier must be laid under the insulation and a denser membrane should also be mounted on top of the insulation.

According to the same scheme as floor insulation, you can insulate the ceiling or ceiling in a wooden house with your own hands. The difference will be that a vapor barrier layer with a high penetration coefficient will have to be mounted on top so that moisture from the insulation is not removed from the inside of the room, but to a ventilated attic or outside.

Parquet and parquet board

Parquet floors can be either a stacked combination of individual slabs or a parquet flooring. In both cases, the parquet is laid on an even, prepared base. It can be a cement-sand screed or sheet wood material. So that the parquet floor is not cold, it can be insulated in several ways.

A significant insulating effect is provided by the use of a foamed polyethylene substrate, which is laid under the parquet board. This substrate is similar in structure to the insulating material penofol. The only difference is that it does not have a foil layer.

Note! If the type-setting parquet is laid on a plywood or chipboard base, a penofol insulating layer can be placed under the wood base directly on the surface of the concrete slab.

When parquet slabs are glued directly onto a cement-sand screed, it needs to be insulated.

In this case, penofol or penoplex is used. To do this, a layer of insulation is glued to a reinforced concrete floor slab, and then a screed is poured. Previously, along the perimeter of the room, a foam foam tape must be glued to the thickness of the screed, or foam foam plates are laid.

They need to be placed along all walls and partitions, including along interior ones, since they perform two functions - they isolate the screed from the cold outer walls of the building and are dampers that compensate for changes in the size of the screed due to heating.

Having monolithic a heating cable with a sensor from the floor heating system into a screed, you can get an additional type of heating. Usually it is called that - a warm floor. The cable must be mounted using special fasteners before concreting. The wires supplying the cable and connecting wires of the sensor must be brought out in advance to the installation site of the temperature controller - the control panel for the heating system. Periodic inclusion of heating will provide a comfortable temperature throughout the room.

Due to the constant increase in utility bills and the desire to make their homes warmer and more comfortable, the owners of apartments and houses are increasingly thinking about floor insulation. The sense of this procedure is felt almost immediately, the process does not require significant investment, it is also facilitated by the fact that it can be carried out in a wooden house without dismantling the old floor covering, and it is cheaper, thanks to the possibility of designing it yourself, without spending the planned budget on calling a specialist. The main thing is to decide which of the existing heaters is better and how to properly lay the heat-insulating layer.

Why is it necessary to insulate the floor in wooden houses

An additional layer will not only eliminate the cold walking on the legs and raise the overall temperature in the room, but also eliminate the following possible problems:

excess moisture;
the appearance of condensate, which causes dampness and leads to the formation of fungus and mold;
the occurrence of microorganisms;
decay process in wooden structures.

The combination of these facts allows us to conclude that insulation is necessary.

Work performance technology

The double floor is a structure implemented on two levels:

draft- these are boards fixed on beams, on top of which an insulating flooring is supposed.
Finishing- a tier serving for paving the last layer of insulation.

The general laying technology is a collection of heat-insulating "pie":

dismantling of the old floor;
along the bottom, over the entire area, auxiliary boards are attached;
logs of the required size are treated with antiseptic agents to prevent decay;
prepared logs are laid on top of the support layer with a distance of 0.6 or 0.7 m, maximum - 1 m.
between them, the selected insulation is placed on the draft layer. If a solid version is used as it, for example, polystyrene foam, the joints must be treated with silicone, foam or other mixtures to eliminate gaps;
a vapor barrier is placed on top of the insulating material, which is mounted to the logs with thin bars 20x30. To improve the energy-saving effect, the joints are glued with a special adhesive tape containing metal.
Next, the main floor layer is laid.

Also, there are methods in which an impromptu net is used, which is a strong weave of fishing line. It is attached to the beams with nails and is used as a "black" floor, however, over time, such a design can stretch and sag, thereby making the idea unreliable.

In private houses, insulating the floor of the first floor, the raw materials are also laid along the logs fixed on small brick hills, while laying waterproofing and plank sheathing between them.

How to choose the right thermal insulation material

The selection of good material is an important part in the process of forming insulation. Several key parameters should be considered.

The weight materials is not so important for the owners of one-story wooden houses. Such structures, in themselves, are lightweight and create a minimum load on the foundation. This parameter is relevant only for high-rise buildings with wooden floors.
moisture resistance take into account if insulation is carried out in places with high humidity - saunas, bathrooms or kitchens, as well as in regions characterized by humid climatic conditions.
Duration of operation directly affects how often the owner will need to carry out repair work to restore the coating.
Thermal conductivity- one of the most pressing issues, this indicator determines how much heat will be kept inside the housing.
Difficulty of installation sometimes the determining factor. Everyone wants the process of warming to go as quickly and easily as possible. Accordingly, the material is chosen.
Basement or basement involves a thicker layer of insulation, which will become a significant barrier to cold air.
Ceiling height often limits the choice of insulation. In small rooms, you will have to limit yourself to a thin layer to save space.
Period of residence in the building. If this is a dacha or a garden house where you appear once a month, you should not overpay and put a thick layer of expensive building materials on the floor.
fire resistance important for wooden houses. The thermal insulator should not support combustion, and also emit an unpleasant odor when the house is heated in the summer.

You need to choose products depending on the above parameters, as well as their cost and the budget allocated for insulation work.

Popular types of thermal insulation materials

Practicality and ease of use is one of the main criteria in the selection of raw materials for home insulation. Today, the line of similar products is represented by a wide range for any need. Hard types of insulation are used on flat surfaces, while soft and flexible ones can be used in finishing almost any surface.

in rolls

The main components of such products are mineral wool and crushed cork. This form of insulation is characterized by softness, low specific gravity, low density. This allows you to mount it on all types of planes, including curves and torn ones with large differences. When laying, there are no butt joints, which makes it possible to avoid cold bridges.

in slabs

Insulation in the form of plates is very convenient in terms of laying, if the dimensions of the openings that need to be insulated are known in advance, for example, in the inter-rafter zone of the attic or between the logs in the floor. It is lightweight and does not change its dimensions during installation. It has a low coefficient of thermal conductivity.

This type of insulation is a special mixture, which, when interacting with air, changes its structure from liquid to foam, and then hardens. With such a product, you can fill almost all the necessary places, including the most inaccessible ones. One of the most common representatives is penoizol. It is applied with special equipment to the surface, filling with itself all the bumps and flaws. The disadvantages of this type of material include a rather high cost.

The main component here is materials in the form of small free-flowing particles, such as slag, woodworking waste in the form of sawdust or expanded clay. They fill all the cavities very well and allow you to achieve good sound insulation. Their laying is carried out both on a conventional soil coating and on a previously prepared base. It is considered quite budgetary and is the best suited for thermal insulation of floors made with wood.

The most popular materials for insulation

Nowadays, hardware stores offer dozens of raw materials for all types of insulation. Therefore, it is not necessary to think for a long time over the question of the better to insulate the floor in the house. You just need to choose the most optimal one that can solve your problem and at the same time will not hit the family budget much. The list of the most popular similar products is as follows:

Styrofoam or Styrofoam

It has a lot of advantages, including excellent thermal insulation, light weight, ease of installation and, most importantly, moisture protection and complete vapor tightness. Due to the latter quality, it is recommended to use it in basements. The thickness of the finish depends on the climate zone, but on average it is 5-15 cm. Its thermal insulation characteristics directly depend on the density - the higher this coefficient, the better it will protect your home from the cold. Such materials have another advantage - if you want to insulate your house cheaply - do it with foam.

Mineral wool

The characteristics inherent in this insulation do not allow its use in concrete screeds. But, for sound insulation and insulation of wooden floors, it is the best fit. Between the first and ground floors, the heat-insulating layer should be 20-30 cm. For other floors, a layer of 10-20 cm will suffice.

Ecowool

Once an innovative material, today it has gained high popularity. It is produced by shredding paper and paper waste with further treatment with antiseptics. Due to the substances contained, this ecowool cannot be used on the ground, but for interfloor ceilings along the beams it will be the best option. The layer in the latter case is placed at 20-30 cm.

A very expensive heater with a lot of advantages. Due to its structure, it can easily fill all cavities. It is not recommended to use it for thermal insulation of floors on beams.

Foam glass

An innovative product obtained by foaming quartz sand. The specific gravity of such raw materials is low, it has excellent noise and vapor barrier characteristics, and is capable of withstanding huge loads without changing its original shape.

Expanded clay

Material that has come to us from time immemorial. Even 20-30 years ago it was one of the most popular and used. Now its popularity is declining due to its large size. The height of the ceilings, especially interfloor ones, does not always allow you to pick up the distance necessary for laying expanded clay.

Fiberboard

It is a complex mixture of cement, wood and liquid glass. The main advantage of such a heat insulator, in addition to retaining precious heat in the house, is a high degree of sound absorption. Its laying on soils is limited, however, for a layer between floors, it will be the best option. Between the basement and the first tier, it is necessary to provide a thickness of 15 cm, and 10 cm is enough for subsequent levels.

Sawdust

Insulation with sawdust cannot be considered the most effective and high-quality way to keep heat in the home, since in order to achieve the required indicators, it is necessary to provide a layer of at least 30 cm. However, it is still used in attics or for the manufacture of more complex materials.

Izolon

This is a polyethylene brought to a foamed state, characterized by a low thermal conductivity with a minimum thickness. At the same time, it is also a sound insulator, which makes its use in demand between the floors of the building. The isolon is laid not “butt-to-butt”, but with an overlap, and the seams are processed with bituminous mastic.

Penofol

The latest modern development, whose action is based on shielding. The reflective surface helps to effectively retain heat, and the ultra-thin and plastic structure allows the use of penofol in the most inaccessible places.

How to insulate the floor in a wooden house yourself

A house built from wood can be made according to different technologies, depending on the wishes of the owner, climatic conditions, proximity to groundwater, etc. Therefore, the methods of floor insulation used also differ. The following are the most common of them.

Remember that major work on a building made of wood can only be carried out after its complete shrinkage, which lasts at least 1 year. If fresh saw cuts were used during construction, the process can take up to 5 years.

With a low underground

Since it is impossible to carry out work from below from the basement due to the low height of the ceiling, the existing flooring will have to be dismantled, which makes the method laborious. If the replacement of the floor cloth is not included in your plans, then you need to perform the work carefully so as not to damage it and avoid problems during the reverse mounting process.

Examine the appearance of the log and remove those that are damaged or defective, and instead fix the bars of the same size. Use self-tapping screws to connect structural elements.
Next, you need to start preparing the subfloor. To do this, take an unedged board and dissolve it into parts that will be less than a lag step, by about 1-2 cm. This is necessary so that the parts are not laid end-to-end.
When the collection of the subfloor is over, it is necessary to close the flooring and logs from above with a vapor barrier layer.
After - install the logs for the construction of the finished floor and place the selected insulation between them, covering it with another layer of vapor barrier.
Determine if you need an additional counter batten. If there is a gap of 20 mm even without it, feel free to lay the previously dismantled floorboards.

If you work in a room with high humidity, replace the vapor barrier layer with a waterproof layer.

According to a similar principle, the floor is insulated in a wooden house on screw piles, with the exception that a layer of wind protection is laid between the wooden base (mounted skeleton) and thermal insulation, which is necessary to prevent weathering of the insulating raw materials.

Above the cellar

With such a task, it will be convenient to carry out work in a non-standard way, and insulate the floor from the underground:

To do this, you need to go down to the cellar and attach a moisture-proof film to the ceiling from below.
Further, a beam or a thin crate is attached to both sides of the beams, but if the room is damp, a galvanized plasterboard profile is used.
The insulation is cut to a size slightly larger than the lag pitch (up to 30 mm), due to which it is tightly placed between them, leaving no gaps.
Cross rails are attached to the previously fixed support beam or material used in its place to support the insulator, a waterproofing layer is applied to them and a finish coating is applied at the discretion of the owner.

According to this scheme, insulation is placed on the side of the first floor.

On the concrete floor

In a wooden house with concrete floors, the process of warming can be carried out in two ways: traditionally - on logs and by equipping a screed. The choice depends only on the funds allocated for materials and work. More often they choose the first option - due to the speed of its execution, where a plank flooring is obtained at the finish.

It is much easier to make a concrete slab warm - it initially has a flat surface, and the weight of the entire insulating layer does not matter.

Using the first method, it is necessary to mount a crate on concrete that replaces logs using bars. It is between them that there will be a heater. Boards are fastened with anchors. Their thickness depends on the type of insulation, so you need to make all measurements in advance. At the end, a finishing floor is laid. A vapor barrier layer is laid between the wooden structure and the ceiling. If the latter is not available, you can use a thin plastic film.

Insulation of a reinforced concrete slab under a screed is even easier. The best option for thermal insulation is expanded polystyrene or the so-called Penoplex. It is attached to reinforced concrete, and all the cracks formed are blown out with foam. Further, either a screed of reinforcing mesh and concrete is installed, or OSB, drywall or plywood flooring is laid, on which the finish coating is subsequently mounted.

The above preparation is suitable for the formation of a "warm floor" system of any type: electric or water.

If you use a layer of expanded clay instead of polystyrene, you can significantly reduce the cost of construction. A layer of supernova isolon and penofol will be reliable and of high quality.

Arrangement of a double floor

It should be noted that this option is only suitable for rooms with high ceilings, in small rooms, it will take up a lot of space (up to 20 cm).

But on the other hand, such a technology will make it possible to insulate the floor in an old wooden house without dismantling the already lying floor. For its implementation you will need:

Dismantle skirting boards and prepare the supporting surface - replace damaged areas, seal cracks and cracks with mounting foam.
By analogy with other options, after the formation of a high-quality subfloor, logs are laid in increments of 60-90 cm. If the flooring is planned from OSB, 30-40 cm will be enough.
In this case, you need to use the level, and in places of inconsistencies, file the upper edges of the beams with a planer.
After providing a flat surface, the base is covered with a moisture-proof layer with a 10-centimeter margin on the walls.
The selected type of insulation is laid between the lags and covered with waterproofing.
After - the flooring and the selected cladding option are mounted.
At the very end, the missing skirting boards are screwed on - this way you can mount the insulation from above - without opening the floor.

Regardless of which insulation is chosen: bulk, roll, slab - it is important to leave a gap between it and the floor covering for ventilation. If the height of the lag was not enough for this, a counter-lattice is formed.

№	Floor board thickness, mm	Distance between lags, cm
1	20	30
2	25	40
3	30	50
4	35	60
5	40	70
6	45	80
7	50	100

Results

Now you know how to properly insulate the floor in the house. Estimate the height of the room, inspect the condition of the existing flooring, plan methods and decide on a heat insulator in advance. Choose only high-quality materials from trusted manufacturers and follow the instructions clearly when carrying out work - then the design will serve you and future generations reliably and for a long time.

How to insulate the floor video instruction

Do-it-yourself floor insulation in a private house is quite an affordable task, and it can be solved without involving professional builders. The main thing is to decide on the choice of thermal insulation material and the technology for carrying out insulation work. This will largely depend on the design of the floor.

It is necessary to insulate the floor in any case, treating this task with maximum responsibility. Without this, comfortable living conditions will never be created in the house, even if you spend huge amounts of money on the operation of the most advanced heating system and other climate control equipment. Thermal insulation bet is money down the drain!

The publication will consider the materials used for thermal insulation, various insulation technologies, depending on the design of the floors.

Materials for floor insulation in a private house

The first thing to do is to decide on the choice of thermal insulation material that is suitable for the floor of a particular design. Therefore, when considering the characteristics of heaters, it will immediately be noted which floor they are suitable for, and an overview of the technology for their application will be given.

So, today, mineral wool (glass and basalt), various types of expanded polystyrene and expanded clay are most often used for thermal insulation of floors. It should be noted that there are other materials for insulation, for example, ecowool or polyurethane foam. However, their use will require special equipment and experience with it. That is, it is difficult to bring them under the category of "do it yourself".

There are other, let's say - more "exotic" heaters, for example, foam glass plates or cork. But they have not yet received much distribution, apparently due to inaccessibility or excessively high prices. Our article is designed for the average home owner who wants to do the insulation on their own.

Synthetic foam insulation

This group includes the most commonly used thermal insulation materials today - these are ordinary white foam, extruded polystyrene foam and polyethylene foam (). These heaters gained their popularity due to their low thermal conductivity and quite affordable cost. In addition, foam materials have a number of other advantages, but they also have very significant disadvantages.

Extruded polystyrene foam

This material is made from the same raw materials as the familiar white foam, but using a completely different technology. Therefore, it has improved characteristics.

It is better not to consider white foam plastic as a floor insulation at all, and it is also better not to produce it. To be honest, it has no place at all in the system of internal insulation of a residential building - there are too many shortcomings, including those that are extremely dangerous for humans. In extruded material, these "minuses" are still significantly reduced. Therefore, it is better to perform - this is what extruded polystyrene foam is called.

The disadvantages of this material are the following features:

The flammability of the insulation, it belongs to the flammability group G2÷G4.
Low heat resistance - at elevated temperatures, the material begins to "float"
Low vapor permeability, that is, the material is not breathable. Again, this is sometimes a clear advantage.
Low tensile and compressive strength of thin insulation.

As a substrate, ordinary foamed polyethylene up to 3 mm thick is used. And the foil version can be laid on top of other rigid insulation, or also as a reflective substrate. In addition, foil material is usually laid under the "warm floor" system, moreover, any of its possible varieties - electric cable or film infrared, water, or other floor covering.

Sheets of foamed polyethylene are stacked end-to-end and sealed with foil tape. The coating must be airtight, since very often it is the layer of foiled polyethylene foam that is considered as the necessary vapor barrier.

So, the material is very good, but it is designed only for sharing with other heaters. Relying on the fact that only its use can create a full-fledged effective thermal insulation of the floor of the first floor of a private house is simply naive.

Mineral wool

On sale you can meet three types of mineral wool - stone (basalt), glass and slag. Slag wool is practically not used in housing construction, as it does not have outstanding characteristics, and often does not meet the requirements of sanitary standards. Therefore, the features of this type of insulation will not be considered.

Basalt and glass wool also differ in their characteristics, but both of these types are widely used in insulating structures. It is they who will be considered in more detail.

glass wool

Glass wool is made from environmentally friendly raw materials - sand, cullet, borax, soda and limestone. From the melt of materials, fibers are formed that are rather fragile and brittle, but when they are pressed into mats using binders, a sufficiently stable air-saturated structure is obtained that has high insulating abilities.

Glass wool can have different thicknesses, have different densities, be produced in regular and foiled form. When using the second option for floor insulation, mats or slabs are laid with foil up, that is, towards the room. Due to this, the heat from the room, falling on the insulation, is reflected back.

Glass wool has many advantages. These include high thermal insulation capabilities, fairly high heat resistance, resistance to fire and chemistry, and the affordable cost of the material.

Disadvantages - rather high fragility of the fibers. This creates difficulties in work - the material is caustic, capable of causing severe irritation of the skin, respiratory organs and mucous membranes. In addition, such brittleness is a prerequisite for the gradual shrinkage of the material during operation, especially if there are vibration loads. And this leads to a decrease in thermal insulation characteristics.

In addition, not everything is safe with glass wool and with exposure to water - it can get wet and waste its insulating qualities. Measures are required to prevent its saturation with moisture.

Stone (basalt) wool

Stone wool has the most optimal characteristics of all types of insulation in this class. This heat-insulating material is produced from the melt of basalt rocks, from which thin fibers are drawn, which are much stronger and more elastic than glass.

High-quality basalt insulation - the most resistant to moisture. Such stability is achieved by special processing, and sometimes it reaches almost hydrophobicity - water does not penetrate into the structure of the material at all.

Basalt wool from leading manufacturers is highly resistant to open fire and can withstand very high temperatures. Therefore, such material is classified as NG - non-combustible heaters. A very important quality for any home!

Manufacturers are trying to minimize the possible emission of formaldehyde. Thus, basalt insulation labeled "ECO" or "Eurostandard" is environmentally friendly - not phenol-formaldehyde, but safe acrylic resins are used as a binder. It is clear that the price of such products is much higher, but they are really worth it.

A significant drawback of any mineral wool is that mice like to arrange their nests and passages in them. Moreover, for some reason, rodents are not at all afraid of the causticity of the fibers - they feel great in warmth and dryness. And if the characteristics indicate that the material does not attract rodents, this should be treated with a fair amount of skepticism.

It is possible to protect the heat-insulating layer, for example, by closing its sections accessible to rodents with a metal mesh with cells 2 ÷ 3 mm in size - it will not succumb to the teeth of mice.

* * * * * * *

Mineral wool is used in various floor insulation schemes. Materials of low and medium density are suitable for laying between beams or joists. High-density slabs can be used for insulation on the ground or floor slab, followed by pouring a reinforced screed.

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Expanded clay and its use for insulation

Expanded clay is one of the most practical, reliable and durable, as well as environmentally friendly heaters. This material is produced from refractory purified clay using the technology of its special firing.

This material has a lot of advantages:

Expanded clay does not contain toxic components, as it is a natural material.
Good thermal insulation performance. At the same time, these qualities do not decrease throughout the entire operational period.
Low moisture absorption. Expanded clay does not swell and does not deform.
Excellent soundproofing ability. Moreover, the smaller the fraction of the material, the higher the sound insulation.
High vapor permeability.
Fire safety. Expanded clay mass not only does not ignite, but also prevents the spread of fire.
High frost resistance, resistance to temperature extremes.
Resistance to biological influences. Fungus or mold does not form on expanded clay, since it does not contain a nutrient medium for such microflora of organisms. Expanded clay is not tolerated by rodents - they only do not live in it, but they cannot make passages in it either.
Simplicity and variety of use cases.

Expanded clay also has disadvantages, but they are much less than advantages. And the main thing is that the coefficient of thermal conductivity is still almost three times higher than that of expanded polystyrene or mineral wool. That is, a layer of insulation will require a more significant

Expanded clay is used in various floor insulation schemes.

The first option is the simplest of all - this is backfilling of expanded clay on the ground in the underground of a wooden floor. Before backfilling, a waterproofing material is laid on the soil base, which is understood and fixed on the walls to a height higher than the thickness of the backfill by 50÷100 mm.
Another option is to create bulk layers of the required thickness along the soil, followed by pouring a reinforced concrete screed.
Another way to insulate with expanded clay is to fill it between lags or floor beams on the subfloor:

If fine-grained expanded clay is used for backfilling, then the subfloor must be prepared. The gaps between the boards, if any, can be sealed with a clay-lime mass, which is also a natural material. It will securely hold the backfill between the lags on the subfloor;

An alternative option is flooring on the subfloor and parchment logs. His canvases are overlapped by about 100 mm. Glassine is also fixed on wooden structural elements with staples driven in with a stapler.

The next step between the lags is filled with expanded clay mixture and evenly distributed throughout the space. A layer of vapor barrier film is sometimes laid on top of expanded clay.

And, finally, sheets of plywood or floorboards are laid and fixed on the logs.

Another option for using expanded clay is mixing it with a liquid cement-sand mortar. Concrete binds expanded clay granules together, which increases the strength of such a base.

Such material becomes especially relevant when insulating floors on the ground - a leveling screed will be poured from above. True, they also use it with floors on logs, filling the entire space under the future flooring with mortar.

Since the insulating qualities of expanded clay still leave much to be desired, which requires very significant layers of backfill, it is often used in combination with other thermal insulation materials - expanded polystyrene or mineral wool. A calculation is made in advance which combination of material layers will provide the expected thermal insulation.

How to calculate the thickness of floor insulation on the ground?

The main options for insulating the floor of the first floor of a private house

Now more about how the floor insulation is carried out in a private house

Ground floor insulation

This approach is often practiced if the house is being built on a strip foundation. Expanded clay (alone or in combination with other material), rigid insulation boards (extruded polystyrene foam) or mineral wool blocks of increased charge, specially designed for such purposes, can act as a heater (this is specified in the passport characteristics of the mineral wool). One thing that is common to any heaters in this scheme is that they are closed from above with a reinforced screed.

It might look something like this:

The soil (pos. 1) is carefully compacted, while its surface is leveled to the maximum.

From above, sand filling is made (pos. 2), in layers, also with careful tamping. The thickness of the backfill is usually at least 100 mm (in compacted form).

Next, an optional but highly recommended layer of lined geotextile is shown (item 3). It will be a big plus for the stability of the entire “pie” being created, it will serve to separate the sand and gravel (crushed stone) layer, which will improve the drainage capabilities of this design.

Above, also with a rammer, a layer of crushed stone or coarse gravel (pos. 4) is filled up, on which the so-called “concrete preparation” (pos. 5) is performed. This is a poured layer of lean concrete (marked strength M50 is enough). On this basis, it is much easier to carry out further work that will directly swing the insulation.

A layer of waterproofing is laid on the concrete preparation (pos. 6) - the insulation must be protected from moisture from the ground. Rolled bituminous waterproofing can be used for these purposes - it will perfectly lie on a fairly solid foundation for concrete preparation.

Then the thermal insulation material of the required thickness is laid (pos. 7). About the calculation of the thickness is described separately - the link has already been given above. Possible combinations of insulating materials are also sorted out there, so that the thermal insulation becomes complete.

Further, the insulation is covered with another layer of vapor-permeable waterproofing material (pos. 8), which can be a polyethylene film, but very dense, at least 200 microns thick. Cloths are necessarily laid with an overlap of 150 ÷ 200 mm and sealed along the seam lines with moisture-resistant adhesive tape. Waterproofing should go on the walls to a height above the surface of the future floor. The purpose of this layer is to prevent water from flowing out of the concrete solution when pouring the screed, that is, to create optimal conditions for the hardening and maturation of concrete.

A reinforcing mesh is laid on top of the waterproofing, the cross-section of the rods and the size of the cells of which depend on the expected degree of load on the floors. But these are general construction issues that only indirectly relate to the problems of insulation under consideration. The mesh must be lifted from the waterproofing layer so that it is approximately in the middle of the thickness of the screed.

After hardening, maturing and gaining brand strength, the resulting screed will serve as a universal base for any floor finish.

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Insulated floor over slab

Such a scheme in a private house is rarely used, but, nevertheless, it should be mentioned. Moreover, it is very similar to the previous one, but much simpler. If only because there is already a rigid, reliable foundation that does not require additional modifications.

What are the features here?

The base is already ready - this is a floor slab (pos. 1) above the cold underground, as a rule - hollow. It must be without fail primed with a deep penetration compound, and it will not be superfluous to provide a waterproofing layer on it (pos. 2). Coating insulation or even a dense polyethylene film is quite enough here.

The next layer is again waterproofing (pos. 4), which will protect the insulation from moisture penetration from above and provide the optimal water-cement ratio when the screed solidifies.

Well, above is a reinforced screed (pos. 5), in which pipes or a “warm floor” heating cable can also be located. And the entire structure is crowned by the selected floor finish (pos. 6).

Floor insulation along logs or floor beams

But this option occurs, perhaps, more often than all others. And above all, because such a scheme turns out to be practically the only possible one if the house rests on a pile or column foundation. But even for a strip foundation with a high base, it is quite applicable. "Heavy" materials such as cement, sand, gravel are not used here - wood or materials based on it become the main one. Well, plus, of course, the heater itself.

The schematic diagram can be represented as follows:

On the floor beams or logs (pos. 1), cranial bars (pos. 2) or support boards are stuffed. The lights will serve as the basis for the installation of the subfloor (pos. 3). For this flooring, both low-grade boards and sheet materials such as plywood or OSB can be used. The flooring can be solid, but more often the boards are mounted with a vacuum - both for reasons of economy and for better ventilation of the insulation.

Waterproofing is laid on the subfloor - wind protection (pos. 4). Important - this layer should not prevent the free exit of water vapor, so that moisture does not linger in the insulation. Sometimes, with frequent arrangement of boards or when rigid polystyrene foam boards are used as thermal insulation, this layer is not laid at all - there is no need to fear direct water from below, and the wind effect with a well-equipped base is unlikely to be so great that it can cause damage insulation.

Even, a layer of thermal insulation of the required thickness is laid (pos. 5). The illustration shows laying in one layer, but usually this is not enough - at least two are required. But it's for the best - the slabs or mats of the upper layer overlap the joints of the lower one, and there are practically no cold bridges left.

Next - a prerequisite: a layer of reliable vapor barrier (pos. 6). The humidity level indoors during the cold season is always much higher than outdoors. And so that those looking for any loophole to get out of the water vapor do not penetrate into the insulation, it is required to put a reliable hermetic (without exaggeration) barrier.

And finally, a plank or plywood (OSB) floor covering is laid on top (pos. 7). In the diagram, again, a simplification is allowed, but in fact it is recommended to leave a ventilation gap of about 20 ÷ 30 mm between the vapor barrier membrane and the flooring. This is easy to do by installing additional rails of the counter-lattice along the lags - they will additionally press the membrane and provide the necessary clearance.

It is clear that the thickness of the insulation with such a scheme must be calculated in advance, since in this case it also directly affects the choice of the section of lumber for beams and logs. You will have to carry out a not particularly complicated thermal calculation.

How to calculate the thickness of the wooden floor insulation on the logs?

You will be introduced to the algorithm for such calculations by a special article of the portal -. It also contains a handy calculator.

One more nuance. To protect the insulation from penetration of mice into it, you can also use a metal mesh. It is mounted directly on the subfloor boards under the waterproofing layer. The edges of the grid are raised to the wall above the thickness of the insulation by 100 ÷ 150 mm. After laying the insulation, the mesh is folded onto its surface. After that, the insulation is completely closed from above with the same mesh - it is shot to the lags with brackets. Perhaps, such measures will seem superfluous to someone, but it really helps if you do not leave loopholes for mice.

Insulation of a wooden floor on logs

This section of the article provides step-by-step illustrated instructions for insulating floors with mineral wool.

The most important thing in warming a wooden floor, raised above the ground by 300 - 500 mm, is the choice of the optimal material and its high-quality, according to all the rules, laying

The first thing to check when deciding to insulate such a floor is the presence of ventilation in the underground space. If there are no air vents in the basement of the foundation, then they must be equipped. The lack of ventilation with such floor insulation will lead to the appearance of dampness in the underground space, to rotting of wooden structural elements, to their damage by fungus.

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The total area of all ducts must be at least 1/400 of the floor area of the first floor, but at the same time - at least 0.85 m². The area of one vent is usually around 0.05 m². that is, it is easy to calculate the required number and then consider their uniform placement on the base. In this case, the extreme air ducts should be located no further than 0.9 m from the corners of the foundation. and another important condition is the symmetry of their placement, that is, the air on one wall must correspond to a similar one on the opposite. Thus, their number usually turns out to be even.

However, we again delved into general construction issues - let's return to floor insulation.

So, the insulation of an old wooden floor (if we are not talking about installing a new one during construction) can be done in several ways:

Using an old plank floor as a subfloor. This option is possible if the boards are in good condition, that is, they do not have signs of decay and are not moistened from the inside. In addition, it must be taken into account that the floors will rise by about 250 mm. If the ceilings in the room are high enough, then the insulation on the old coating, without dismantling it, seems possible. But, to be honest, they resort to this path - infrequently.
The second option involves the dismantling of the boardwalk and laying insulation under it. In this case, the dismantled floor boards, if they are in a satisfactory condition, can then be returned to their place. If the boards are supposed to be reused, then when dismantling, it is recommended to number them.

Naturally, if a new floor is being built, then they start from scratch, that is, with the installation of a subfloor - and then in order.

Below we will consider the option of insulation, in which the old floor is dismantled. Moreover, if the insulation will be carried out in an old house, an audit of the underground space, as well as the reliability of the floor beams, will never be superfluous.

To work, you will need the following materials:

Warming material. In this case, it is mineral wool. As practice shows, and calculations confirm, in private houses in most regions of Russia it is recommended to lay this insulation with a thickness of at least 150 or even 200 mm. this usually involves a minimum of two-layer installation.
Boards or plywood for subfloor installation. Boards 10 mm thick and 150 mm wide will be enough.
Beam for counter-rails, for example, 30 × 50 mm. The larger size should correspond to the thickness of the lag or floor beam.
Waterproof vapor permeable membrane.
Vapor barrier material.
Self-tapping screws and staples for a stapler.

Illustration	Brief description of the operations performed
	So, having dismantled the boardwalk, you can see the floor beams and evaluate the possibilities of further work. If the floor beams are in good condition, then the first thing to do is to cover them with an antiseptic solution on all sides and allow the coating to dry well.
	Further, you can choose one of the two options - to fix the cranial bars on the supporting beams with self-tapping screws, on which the subfloor boards will be laid, or to fix the boards from the bottom of the floor beams. Each of the options has its drawbacks. When fixing the cranial elements, the space for installing the insulation will decrease.
	Fixing the boards from the bottom of the floor beams, in principle, has no drawbacks, except for the laboriousness of the work. If the height from the ground to the beams is small, then the installation will have to be done while lying on your back. The subfloor is only needed to support the insulation material, so it is not necessary to make it solid or lay boards too often. The distance between them can even be 200÷250 mm. And the boards can be used even unedged. But they need antiseptic treatment to no lesser extent.
	Another option for arranging the subfloor is to fix the transverse boards to the beams with a pitch of 700 ÷ 800 mm, and then lay a longitudinal plank covering on them. Moreover, gaps of 10 ÷ 15 mm can also be left between the longitudinal boards. Gaps are necessary for proper ventilation of the insulation.
	In some cases, sheets of OSB plywood 10 mm thick are used for the subfloor. However, a gap must be left between the sheets every 500 mm for ventilation. Therefore, it will be necessary to prepare pieces of plywood with a length of 500 ÷ 600 mm and a width equal to the distance between the centers of adjacent floor beams (lags). As a rule, it is 600 mm - according to the traditional size of mineral wool insulation.
	The next step is to lay a vapor-permeable waterproofing-wind protection on the subfloor. It is laid to protect the mineral wool from water ingress (which is extremely unlikely in such conditions), as well as from the wind that will penetrate the underground through the ventilation ducts. Membrane sheets must wrap around floor beams. They overlap each other by 100÷150 mm. It is not necessary to glue these overlaps with adhesive tape, tightness is not required here.
	It is necessary to focus on fixing the membrane on the walls. The material should be on them above the thickness of the insulation by 50 ÷ 70 mm. On wooden walls, the membrane is fixed with brackets, and on surfaces made of other material - with double-sided construction tape. Insulation is still recommended to be isolated from possible contact with the walls.
	Next, the insulation material is laid. Here it is important to observe a few nuances. The plates are most often laid in two layers, and at the same time the top one should overlap the joints of the bottom insulation. The standard width of the insulation boards is 600 mm, and it must be laid at odds with the floor beams, so the optimal width between the beams in the light is approximately 550 ÷ 570 mm (just along the axes - 600 mm, and due to the thickness of the beam, the clearance decreases slightly) . However, it is not always possible to comply with such a step, so the plates often have to be “understaffed” with additional fragments. Their joints should also be covered with whole slabs of the top layer.
	A vapor barrier material is laid on top of the insulation and fixed with brackets on the floor beams. This layer is necessary to protect the insulation from the penetration of various fumes into it from the side of the premises. The canvases are also overlapped by 100÷150 mm (on the membranes, the minimum width of the strip of such an overlap is often even marked with a dotted line). But here the sealing requirements are strict: the canvases are necessarily glued together along the overlap line with moisture-resistant adhesive tape.
	Then, if it is planned to create a ventilation gap between the plank flooring and the vapor barrier (and this is highly recommended), then slats 25 ÷ 30 mm thick are fixed to the ends of the beams on top of the vapor barrier. Some craftsmen refuse this design element and consider it optional. But it is still better not to neglect such ventilation - condensate will not accumulate on the vapor barrier membrane.

The insulation is finished - and on top you can mount a plank floor or flooring made of plywood or OSB. But these are questions that are beyond the scope of our consideration.

* * * * * * * *

Now, having at hand several options for floor insulation schemes with various materials, it will be possible to choose the most suitable method for a particular case. By adhering to the recommendations received and strictly following the technology, it is quite possible to independently produce thermal insulation of the floors in your own home. At the same time, not only saving a decent amount to the family budget, but also gaining confidence that the work was done in good faith.

In conclusion, we offer you to watch an interesting video. In it, a completely amateur master produces independent insulation of the floors of his house under construction. To be honest, there is a lot to learn.

Often the wooden floor is made only from a single board, which is placed on the logs. This design is simply cold. The thickness of one board is 27 - 40 mm, which is clearly not enough to keep warm.

To insulate a wooden floor, you need to lay a layer of heat insulator of the required thickness.

There are other features that must be considered in order for thermal insulation to be effective and durable. How to properly insulate wooden floors in various cases - this will be discussed further.

Wooden floor design options

Consider the following structures:

Wooden flooring is made along the logs above the ventilated underground. There are air vents in the foundation, the humidity under the floor is small. Due to air exchange, the temperature rises in summer, and can be lowered in winter.
Flooring made of wood along the logs above the outside atmosphere with a pile foundation with a grillage.
The flooring is made over a damp basement, a cellar.
The flooring is made above the ground without ventilation or laid directly on the bedding on the ground.

Accounting for ceiling heights

When choosing an option for insulating wooden floors, you need to consider the height of the room.

It is considered optimal within 2.35 - 2.5 meters. If more, then heat losses increase, more energy is needed for heating due to the escape of warm air under the ceiling.

In such cases, it would be desirable to reduce the height of the room according to the “heat loss” condition. This can be facilitated by warming the floors with another layer on top of the existing ones. But reducing the height to less than 2.35m is not recommended - the space will become squeezed, uncomfortable. In this case, the insulation layer can only be placed under the floor.

What insulation and how much

The floor will be warm if the thickness of the insulation layer complies with SNiP 02/23/2003, and the heat transfer resistance of the entire structure will be appropriate.

In order not to repeat the calculations, we note that for a temperate climate above the ground (on the ground) you need about 12 cm of polystyrene foam or 15 cm of mineral wool.

But styrofoam is eaten by rodents, it must be securely fenced. Expanded polystyrene in relation to the tree is a vapor barrier, therefore, it accelerates its aging.

But this will not be critical if the lining is not more than 60 percent of the log surface. Another nuance is that it is difficult to place the foam plastic between the lag tightly, cracks appear, which are sealed with crumbs.

What is chosen more often

Expanded polystyrene is dangerous during combustion, therefore, on top of it there must be a cement-cement or gypsum floor with a thickness of 3 cm or more, enclosing it from the living space.

More often, mineral wool in soft mats is used to insulate wooden floors, especially the subfloor. She “converges” well with the tree, and the living creatures avoid her.

Wool does not burn, so the design of the floors is greatly simplified. The material is durable. But you need to create all the conditions so that the cotton wool does not accumulate water.

Laying a heat insulator between the lag

The usual option for placing insulation is between wooden logs, above a ventilated underground. In this case, the logs will become bridges of cold and reduce the effectiveness of insulation by 20 - 25%. But in general, the result is satisfactory.

From below, plywood shields, or any other shield material, but perforated, with holes for ventilation, are stuffed onto the logs, fixed with screws. You can use the boards apart.

Mineral wool is laid on this flooring. It will acquire the humidity of the subfloor, therefore, in order not to reduce the effectiveness of insulation, ventilation through the vents should always be normal, and this must be monitored.

On top, mineral wool and logs are covered with a waterproofing membrane. You can also use roofing material with overlaps of 20 cm. The membrane is screwed onto the wall by 20 cm. Next, the floorboard is laid

If you make a mistake and don't ventilate

Insulation in a wooden floor should be ventilated with air that is vented outside, and not into the living space. This is the main condition for the successful insulation of a wooden floor with mineral wool. Without ventilation, insulation can be placed that does not accumulate moisture - extruded polystyrene foam, dense polyurethane foam.

The photo shows the result of insulation, if waterproofing is not applied correctly (from below, from the ventilation side) and ventilation of the insulation is not provided.

Drainage of water from mineral wool after cutting the waterproofing from below.

double floor

If the height of the room allows, then you can install an additional one on the existing floor. Logs are installed across the lags of the lower floor, if necessary, aligned in height.

Mineral wool is laid and necessarily separated from the living space by waterproofing. It is covered with a new floor board from 32 mm thick. The thickness of the insulation is the same.

You can save money by installing a thinner crate on the lining in increments of 0.6 meters, but the lining should well redistribute the load on the subfloor.

Above the cellar, on the ground

It is important to prevent the insulation from becoming wet. Therefore, waterproofing is placed above the basement or cellar, and ventilation is provided on top of it for ventilation in the basement. Logs with insulation and top waterproofing are located higher.

If ventilation is not possible, extruded polystyrene foam remains to be used. When laying, it is important to prevent gaps with lags and between sheets.

The thickness of extruded polystyrene foam can be reduced up to 60% of the thickness of mineral wool. But from above, the insulation is protected by fireproof material, possibly between the lags.

Pile foundation with grillage and wooden floors

The fundamental difference is that under the floor there is street temperature and the wind is walking. Then, for soft mineral wool mats, with a density below 160 kg / m 3, a windproof superdiffusion membrane is additionally introduced. It will allow steam to come out of the wool, but it will protect the insulation from blowing with a jet with heat loss.

The thickness of the mineral wool insulation must be increased in accordance with SNiP. For a temperate climate - about 20 cm. In this case, wooden logs become essential cold bridges, so the wooden floors should be with a counter-lattice and place part of the insulation on top of the log.

Wooden floor on fill or concrete base

Between the floor and the base, which has the temperature of the soil, there should be a layer of insulation. A typical solution is to use extruded polystyrene foam with a thickness of 10 cm or more and pour a floating screed over it.