How to insulate a floor with wooden ceilings. How to insulate a floor without dismantling a wooden house

A wooden house requires especially careful thermal protection, since if the temperature and humidity conditions are violated, the wood begins to rot and lose its strength characteristics. It will help prevent this effective insulation. Before you begin work on protection from the cold, you need to figure out how to properly insulate the floor in an individual wooden house.

Why insulate a wooden floor?

Wood compared to concrete is enough warm material, but when building a frame private house or a house made of timber with your own hands, it is not always possible to achieve a rational balance of the thickness of the structure in terms of strength and thermal conductivity. To reduce the consumption of materials on walls and foundations, thermal insulation is necessary. It is possible to carry out insulation work both in an old building that has been commissioned for a long time, and in new construction.

Insulating the floor in a wooden house can prevent the following problems:

• the appearance of excessive dampness in the room;
• reducing the temperature in the task;
• condensation, which causes mold to appear;
• the appearance of fungus and other microorganisms dangerous to humans;
• increased heating costs;
• destruction wooden structures from the inside.

By doing the work yourself you can significantly reduce costs. Now there are many materials, the use of which does not require special skills and high qualifications.

Diagram of all heat losses wooden house.

Which floors require insulation?

The following structures need protection:

1. cold basement floor pie;
2. attic floor;
3. interfloor slab design.

When interfloor option the material is used as sound insulation. In this case, you need to provide a layer 3-5 cm thick.

Insulating the floor of the first floor in a wooden house allows you to provide comfortable living conditions. Most heat loss occurs through the ceiling top floor, therefore it is necessary that the thermal insulation is selected and installed correctly.

Materials for work

To properly insulate the floor in a wooden house, you need to choose high-quality insulation, having all the necessary properties. Insulation can be carried out both from the inside of the room and from the cold air side.

For insulation with your own hands attic floor from the inside or below the basement, it is better to use lightweight materials that can be easily attached to the floor pie from below. In this case, it would be correct to use:

• mineral wool in rolls;

These materials will ensure maximum convenience when insulating the ceiling with your own hands.

When insulating frame house, in houses made of timber or logs, work can be carried out from the inside of the room for the floor of the first floor and from the outside for the last. In this case, it is better to insulate the floor along joists or beams, since this will prevent the load from being transferred to the fragile material. For this type of work you can use the following materials:

More information about insulation with sawdust and expanded clay can be found in the articles and. These materials have such advantages as natural origin and low cost, so if you need to reduce construction costs or insulation in an old building and ensure complete environmental friendliness, it is better to use them. However, they are less technologically advanced compared to other materials.

IN Lately the method is also gaining popularity. This method is good for its low labor intensity and high efficiency.

Floor insulation technology

It is important to lay the insulation correctly, observing the correct order of all layers. The floor pie when insulating the attic floor, the floor of the second floor or the first has not always noticeable, but significant differences.

Insulation of the floor of the first floor from below

In this case, when carrying out work with your own hands, the materials should be correctly laid in the following order:

1. waterproofing;
2. insulation;
3. vapor barrier;
4. ceiling design.

When building a house from timber or frame, the material is secured along the beams. After which the filing is performed. As a protection against moisture and steam, you can use ordinary polyethylene film. As a second option for waterproofing, moisture-proof membranes are used. If all layers are laid correctly, the structure will be reliably and competently protected from the cold from the point of view of heating engineering.

This method is very labor-intensive and is used only if it is not possible to insulate from the inside.

Also, the method is perfect for insulating from below.

Insulation of the ground floor floor from the inside

Carrying out work under the ceiling is quite inconvenient, therefore, when constructing a frame house or a building made of timber, insulation of the first floor ceiling is often carried out using beams from above. In this case, in addition to the previously mentioned materials, you can use bulk materials such as sawdust and expanded clay. When carrying out insulation with your own hands, correctly lay all layers in the following sequence:

1. floor design;
2. waterproofing;
3. insulation;
4. vapor barrier;
5. clean floor.

The vapor barrier must be placed from the inside of the room, so it will work correctly, preventing damage to the floor along the timber beams.

Insulation of interfloor ceilings

In the first case, the insulation extinguishes airborne noise: human speech, music, etc. In the second case, the structure is also perfectly insulated from impact noise– steps, jumps, etc.

Proper sound insulation of interfloor ceilings is the key to comfortable living for all family members.

Insulation of the ceiling of the upper floor from the inside

Installing insulation from the inside does not provide maximum protection for structures, but it can be used as a second option for laying insulation. In this case, the insulation is mounted on the beams from below the floor. It would be correct to arrange the layers in this order:

1. vapor barrier;
2. insulation;
3. waterproofing;
4. beam-based floor structure.

Insulating the attic floor

When constructing and repairing a frame house, a house made of timber or logs, it is better to insulate the attic from above. This method has the following advantages:

• ease of installation;
• the possibility of using inexpensive bulk materials;
• competent thermal protection;
• insulation of not only the room, but also the ceiling along the beams of a house made of timber or frame;
• prevention of condensation in the thickness of the ceiling.

To ensure proper protection, the layers are laid in the following order from bottom to top:

1. floor design;
2. vapor barrier;
3. thermal insulation material;
4. waterproofing.

Calculation of insulation thickness

To perform a full-fledged thermal engineering calculation of the structures of a frame house or a building made of timber, it is not necessary to have a construction education. When performing calculations, it is important to know the thickness of all layers of the cake and their thermal conductivity. It's quite easy to find out.

The calculation will allow you to perform proper insulation houses made of timber and prevent waste of materials. All calculations, taking into account the search for source data, are unlikely to take more than half an hour. Typically, layers such as waterproofing and vapor barrier are not taken into account.

A competent choice of insulation method, type of material and its thickness can eliminate many problems during operation. During the construction of multi-story buildings residential buildings, the question of insulation does not arise: it is required. The correct selection of thickness and the presence of measures for thermal protection of the floor, attic floor and walls are checked by an expert, which considers these calculations on a par with calculations of strength.

In private housing construction, no one checks the presence of proper insulation, but this does not make it any less important.

Probably, many home owners ask themselves the following questions: Do I need to insulate the floors? Will there be any benefit from an insulated floor? How to insulate an old floor without removing it?

We can say with confidence that it is necessary to insulate the floors, since its insulation will help reduce heating costs and you will feel the benefits of this quite quickly. And the main advantage of this process is that you can insulate a wooden floor without removing it.

Floor insulation in a wooden house

Houses made of wood have remained very popular for many years, since they are relatively inexpensive, can last for decades, or even a hundred years, and they are also distinguished by their quality and comfort. If your house is built correctly and has excellent insulation, then you can forget about cold winters while living in such a building.

But, if you intend to make your home even warmer, then we recommend that you start insulating the floor, since in a cold state it can reduce the temperature, which will lead to high costs for heating.

Double floor

A double floor implies a structure of two levels:

• Draft - boards attached to the beams, on which layers of thermal insulation will be laid;
• Finish - the level that serves as the basis for laying the last layer of insulation.

Insulation options and what materials are needed.

There are many options for floor insulation that you can find in any market. building materials.

We will offer you the most popular and effective insulation materials:

• Mineral wool is excellent, soft material, which has a good price and has a high thermal insulation rate. Mineral wool can be classified as a safe insulation material that does not emit harmful substances and does not burn;
• Polyurethane foam - mainly used for vapor barrier;
• Expanded clay - has good thermal insulation properties, but has a fairly high cost;
• Penofol, penoplex, polystyrene foam - synthetic materials, which reflect thermal radiation well and are fireproof.

Installation technology

How to insulate the floor in a wooden house without dismantling the floor? Very easy. Now we will present you with a simple option on how to properly insulate the floor in a room cheaply. So, let's begin.

Work should begin with the organization of a “thermal insulation cake”, which will have several insulating layers. To organize it you need:

• Create a structure from logs;
• Installation of facing boards on logs;
• Lay thermal insulation material between the joists so that the gaps are minimal.
• Can fill gaps polyurethane foam;
• We lay a layer of insulation and install it on top vapor barrier film, which needs to be attached to the joists, secure the overlaps with tape;
• We install the selected floor covering.

Insulated floors on the ground

Floor insulation on the ground will be a “pie” of many layers that will be presented:

1. Mother soil;
2. Bulk layer of soil;
3. Large crushed stone;
4. Sand or cement mortar(which will be needed to level the crushed stone);
5. Waterproofing (in the underground of the house it will prevent moisture from not only the floor, but also the house itself);
6. Insulation (polyurethane foam, mineral wool, penofol are perfect. You can also insulate the floor with expanded clay, which has good thermal insulation qualities, but also has a high cost.

A good option is penoplex. It is as easy to insulate a floor with penoplex as with other materials).

• Screed (main and main layer of the structure);
• Floor covering (“finishing” layer).

To do efficient design, you will be required good materials, patience and several helpers. If you cope with the task, then insulated floors on the ground will retain heat well in your home and will not allow the cold to penetrate.

Calculation of insulation thickness

It is worth considering the fact that each insulation must have its own thickness, which will minimize heat loss.

We will give you a list required thickness for various insulation materials:

• Polystyrene foam - for a wooden house - 300 mm, for a concrete house - 200 mm;
• Mineral wool - at least 300-400 mm;
• Expanded clay - 300-400 mm;
• Polyurethane foam, penoplex, penofol - at least 100 mm;

Mineral wool

As was previously written in the article, mineral wool is a popular material that is non-flammable, resistant to shrinkage, deformation, as well as fungi and mold.

Before installation mineral wool, the sheathing should already have thermal insulation material that will protect it from moisture. If there is already a layer of waterproofing, then we install mineral wool, the sheets of which must be pressed tightly against each other to avoid cracks and gaps. After laying the mineral wool, we apply a layer of vapor barrier, then proceed to installation flooring.

Expanded clay

It consists of porous balls of various sizes that have good thermal insulation properties. Expanded clay is very durable, safe for use, has soundproofing qualities, and in addition, it has a long service life. It is also worth noting its resistance to various temperatures.
The insulation process with these materials is quite labor-intensive process. Afterwards, they are poured onto a coating with waterproofing, then compacted and filled with cement.

Styrofoam

This material is distinguished by its lightness and ease of installation, withstands moisture well, has good sound insulation, and has a long service life. But its only drawback is its low fire safety, that is, it can ignite.

Before laying the foam, there must be a layer of waterproofing on the surface where it will be installed. Afterwards, foam blocks are installed on the surface, followed by a layer of waterproofing and vapor barrier.

Penoplex

Between the joists we lay a layer of insulation, then a subfloor is made on top, on which we can then lay the finished floor. Tip - the gaps between the foam sheets can be sealed with polyurethane foam. Also, penoplex can be used to insulate not only the floor, but also the house itself.

Penofol

Laying penofol from other insulation materials, in fact, is not particularly different. As with any insulation, we prepare the surface, organize a vapor barrier and install the insulation, on which we apply a layer of penofol. When the penofol layer is installed, we begin laying the flooring.

How to insulate a concrete floor

Now we will move a little away from the article and talk a little about choosing insulation for a concrete floor.

These insulation materials are perfect for concrete floors.:

1. mineral wool;
2. Styrofoam;
3. expanded clay;
4. cork insulation, etc.

How to insulate a floor in a frame house

You can also insulate the floor with your own hands in a frame house without removing the old floor on the first floor. In fact, insulation in such a house is no different from insulating a wooden house. We nail bars along the entire length to the joists and then install boards or OSB boards on top. To do waterproofing coating, we make the flooring from a waterproof film that will not allow moisture to pass through. Then, we proceed to the insulation layer.

What is the quality material and what is the best way to insulate the floor? In the room, you can insulate the floor with penoplex, expanded clay, mineral wool, and polyurethane foam. Is it possible to insulate the floor with penofol? Yes, you can. This material almost no different from those presented above. It is also suitable for this process and will create a good insulating effect.

How to insulate a floor in a private house

Floor insulation in a private house is carried out according to the same principle as in a wooden one. The only difference may be the presence of a concrete floor rather than a wooden one.

How to insulate the floor in an apartment

The construction of an insulated surface of an apartment (on any floor) is also not very different from the insulation of a wooden or frame house.

As in a private house, the insulation process begins with the creation of logs, on which boards or OSB sheets are laid, after which we lay down waterproofing and the insulation layer itself. If the insulation is laid, we proceed to install the flooring.

There is another way to insulate an apartment, but it is suitable for those who live on the 1st floor.
We can say that you are very lucky to live on such a floor, since you can insulate basement floor from the basement side.

Thanks to this method, there is no need to dismantle, remove or disassemble the old floor, which makes the work much easier. So, you won’t face the tedious process of creating a new floor.

As you can see, there are many materials for insulation and creating high-quality, complete wooden floor, which will delight you on cold winter evenings.

Thermal comfort in the house, first of all, begins to be perceived by the body through the legs. Therefore, considerable attention is paid to the condition of floor coverings and their foundations. After all, they, especially on the first floors, are among the coldest structures in residential buildings. This is due to the coldness and dampness coming from the ground, as well as convection currents of cooling air inside the premises, descending from the ceiling to the floor. It is not surprising that for houses with wooden floors without ground floor or basement, heat loss through and ceiling structures can amount to up to 30% of the total. A logical question arises: how to insulate a wooden floor in order to minimize such negative indicators, thus increasing indoor comfort?

Design features of insulated wooden floors

In most cases, wooden plank flooring is installed along joists. There are two main ways to create such structures: on the ground or on a foundation with a subfloor. The first option is cheaper and preferable for small structures technical purpose or temporary residence buildings. These could be barns, workshops, saunas, cottages, etc. They are more often used for floor insulation. bulk materials: expanded clay, perlite, polystyrene foam balls, ecowool, tyrsa, straw, derivatives or wood waste (sawdust, shavings, wood pellets).

In the second option, the base can be support posts or strips of brick (concrete, rolled steel, foam concrete blocks with medium density not less than 400-600 kg/m 3) on a pre-prepared sand bed. Floor insulation in a wooden house is placed at a certain distance from the ground surface, forming a ventilated space (underfloor) to remove moisture. In this case, it is more convenient to install a heat-insulating barrier by laying slabs (expanded polystyrene, arbolite blocks, mineral wool) or rolled (felt, penofol, mineral wool) target materials, however, the use of bulk materials is not excluded.

Stages of installing a floor with bulk insulation on the ground

Use this method allowed only in low lying areas groundwater at the stage of construction of a temporary residence structure. Subsequence installation stages floor insulation will be as follows:

1. At the marked construction site, the fertile layer of soil is completely removed to a depth of at least 30 cm - the main depth of the roots of the grass cover, exceeding two to three times the height of the timber (10-15 cm), usually chosen as lags.
2. The bottom of the excavation is carefully compacted.
3. The resulting pit is filled to a depth of 10 cm with coarse-grained mineral material. Suitable: crushed stone, gravel, coarse construction garbage, broken brick and so on. Ideally, it is recommended to use crushed stone or gravel impregnated with bitumen.
4. A pillow of coarse aggregate is compacted, and fine aggregate (10 cm) is poured on top: river or expanded clay sand, fine slag. It is also suitable to install a layer of rich clay - it will simultaneously serve as additional waterproofing for insulating the wooden floor below.
5. The logs are lowered onto the ground base. Their wood must be thoroughly treated with an antiseptic in 2-3 passes. Factory-made target compounds, used machine oil or ozokerite are suitable. For maximum protection from accidental moisture from below, the timber can be wrapped in roofing felt, taking care also to waterproof its ends, and a couple of layers of plastic film can be laid under the entire structure.
6. The space between the joists is filled with backfill to insulate the floor.
7. Semi-rough or semi-rough boards are laid on the timber frame.

If the GWL (groundwater level) is close, then, at a minimum, a high base is required. Then the prepared base is constructed from bulk compacted soil, with which the plinth strip is filled to its upper cut.

Thermal insulation of a wooden floor on joists with an underfloor

Buildings and structures designed for constant use in winter require more thorough floor insulation. At the same time, quite often used for thermal insulation purposes:

• mineral wool,
• insulation from waste wood,
• ecowool,

should be reliably protected from moisture. It cannot be placed directly on the ground surface, even using polymer roll waterproofing. In addition to capillary suction of water from below due to temperature differences, condensation can accumulate in it. Drops of moisture, retained in microchannels or pores of the heat-protective layer, significantly reduce its effectiveness.

Therefore, at high groundwater level, frame structure, including floor insulation on joists, is recommended to be raised above the ground surface by installing a ventilated subfloor. The supports of the frame can be any sufficiently strong pillars with a height of at least 30-50 cm made of non-rotting materials, as well as wood impregnated with antiseptics and hydrophobes.

To reduce humidity in the underground space, it is advisable to cover the soil surface with plastic film. The panels are laid in an overlap of 10-15 cm, sealed with wide tape at the seams. If the supports are monolithic blocks of porous concrete, it is recommended that they be installed directly on the film. Gaskets under the logs made of 2-3 layers of bitumen-impregnated roofing material are placed on the heads of all types of pillars.

In addition to ground waterproofing, it is necessary to install a barrier of breathable waterproofing (membrane) at the bottom of the wooden floor insulation frame. Vapor-permeable material is laid in such a way as not to prevent moisture from escaping from bulk or fibrous thermal insulation. The underground space receives 2 layers of protection on various levels, not only from moisture, the migration of soil radon gas into the living room is also reduced.

Important! The ventilated subfloor space must have a sufficient number of vents (vents) with adjustable gaps. The holes are covered with a fine metal mesh or grate, which makes it difficult for rodents to penetrate into the underground.

If you plan to use sealed insulation for a wooden floor - slab polystyrene foam average or high density, foil thermal insulation based on foamed polymers (isolon, penofol), then the need for a breathable membrane barrier disappears.

Do-it-yourself floor insulation using joists: sequence of processes

Making the base:

• for the base for the supports, you need to choose soil 30-50 cm deep, and the width dimensions are 10-15 cm larger than the column. Fill the pit with sand and gravel mixture and compact it;
• Place supports on the formed pillows. Their step is taken to be no more than 2 m along the span (along the log);
• the heads of the pillars should be leveled in a horizontal plane using patches of cement-sand mortar. If the thickness of the mortar exceeds 3 cm, then it is better to reinforce it with a metal mesh, for example a masonry mesh;
• Lay waterproofing sheets (2-5 cm wider than the posts) on top of the hardened blotches, onto which you already mount the logs. The step between the lags depends on the rigidity of the entire structure: the material used for floor insulation, the thickness of the lag, the type finishing coating, as well as operational loads. For standard designs floors in residential buildings Logs with a cross section of 100-150*50 mm are usually used. Moreover, it is advisable to install them in increments of 600 mm, which corresponds to the width of the mineral wool slabs. With this placement, floor insulation with mineral wool is noticeably simplified, and the amount of its trim is reduced.

Thermal insulation and flooring:

• if you decide to use slab or roll thermal insulation materials, then to lay them it is enough to secure metal mesh along the bottom plane of the lag. If you choose a loose heat insulator, you will have to assemble a lower subfloor to support it. Suitable for him OSB boards, substandard boards, plywood scraps, etc. The rough flooring is mounted directly to the bottom plane of the joists or to their side surface through the skull block;
• floor insulation on joists must be reliably protected from above from exposure to both dripping liquid and moist air. Therefore, lay a water vapor barrier film on top of it. For each subsequent strip, ensure an overlap of at least 10-15 cm over the previous one. Glue the seams with a product designed for similar works tape;
• Now, in principle, you can begin to assemble flooring boards, nailing them or screwing them to the joists with self-tapping screws. However, to preserve the wood, it is better to provide a ventilation gap of at least 30 mm under the top flooring. The boards of the appropriate thickness will be used to lift the covering boards above the joists.

What is the best way to insulate a wooden floor?

1. Sawdust, wood chips, shavings, wood waste and thermal insulation based on them

Insulating the floor with sawdust in a wooden house is economical and also quite effective. The main advantages of this method are the affordable cost of the material, ease of use, and environmental friendliness. However, sawdust in pure form They generate quite a lot of dust and are a favorable habitat for various unwanted small animals. Therefore, it may be better to insulate the subfloor using building materials made using wood waste. TO similar products relate:

• thermal insulation panels. They are blocks 20-50 cm thick, consisting of sawdust, cement and copper sulfate. An effective material with high resistance to biological damage. It is widely used not only for insulating floors, but also for thermal insulation of walls of structures built using a frame method;
• pallets/pellets/pellets made from sawdust and carboxymethylcellulose glue. Various antiseptics and fire retardants are also added to the starting raw materials. Thanks to modifiers, the material produces good thermal insulation wooden floor, having high stability to combustion and biological damage;
• sawdust concrete, for the production of which, in addition to sawdust, mainly coniferous wood, sand is used as a fine filler, and Portland cement is used as a binder. Ready product molded in the form of blocks or slabs;
• wood concrete is the closest analogue of sawdust concrete. Wood chips play the role of filler in it. The feedstock is also subjected to targeted chemical treatment by introducing hydrophobic modifiers into it. In addition, the material can be installed both for sound insulation and for insulating wooden floors.

2. Mineral wool for floor insulation

This is one of the most common and effective materials. Mineral wool based on slag, basalt and glass fibers are suitable for thermal protection purposes. All of them are non-combustible materials, have low thermal conductivity coefficients, and high chemical and biological resistance. However, since slag wool is the most hygroscopic, shrinks significantly, is too brittle, and generates a lot of dust during installation, it is better to refrain from using it.

Low mechanical strength, considered a disadvantage of many types of mineral wool, is not of key importance, since fibrous material will be enclosed in a rigid structure of joists and planks.

Floor insulation with mineral wool in a wooden house can be done either with mats or rolls. It is recommended to use them in two layers with offset joints, and also to choose basalt wool with moisture-resistant impregnations.

3. Insulating a wooden floor with foam plastic

Expanded polystyrene (foam plastic) is the second most popular material for floor insulation and interfloor ceilings. It has significant biological and chemical resistance, low thermal conductivity and vapor permeability. And unlike fibrous and many bulk building materials, it is not afraid of even direct contact with liquid, so it can do without creating a waterproofing carpet between the insulation and the room.

Its disadvantages include: high flammability, some release of carcinogenic substances (decomposition products of the styrene group). Expanded polystyrene insulation of a wooden floor can also be happily inhabited by rodents, at the same time not being too fond of glass wool.

Types of expanded polystyrene

In addition to the usual slab foam, it can be used in bulk form from unbound balls. This form is convenient for both self-use, and in combination with slabs for insulating narrow niches.

In structures without joists (if there is a rigid, level base), it is possible to install extruded polystyrene foam. It is strong enough to withstand laying a semi-rough or finished plank floor directly onto its surface.

4. Ecowool

Refers to thermal insulation materials made from recycled products. Consists of waste paper (80%) and modifying additives, mainly on a natural basis (20%). In other words, ecowool is a homogeneous mixture of cellulose fibers, organic binder (lignin), antiseptic and fire retardant (boric acid). Insulation of floorboards based on it is positioned as environmentally friendly and absolutely safe for human health. It has low thermal conductivity, and after getting wet and then drying, its original properties are completely restored.

Laying insulation on the floor can be done either manually or with the help of special injection units with the assistance of third party specialists. Special equipment also allows you to blow ecowool into the space between the joists even after installing the finishing floor covering.

5. Foil thermal insulation based on polyethylene foam (isolon, penofol)

The use of such modern thermal insulation materials allows you to insulate the floor in a wooden house with almost complete preservation of the infrared component of thermal energy indoors (up to 98%).

At the same time, insulating a wooden floor with penofol or isolon is also its waterproofing. The material is laid end-to-end, sealing the joints with special aluminum adhesive tape.

Important! A distance of 10-20 mm should be maintained between the reflective layer and the inner surface of the floor covering.

6. Spray polyurethane foam

Polyurethane foam has a cellular structure, reminiscent of very dense extruded foam. Is one of the most effective means thermal insulation due to extremely low thermal conductivity. Resistant to biological damage, acids and alkalis. It has low moisture absorption rates and does not require the installation of an additional vapor or waterproofing carpet. It is applied by spraying using special equipment.

conclusions

Insulation wooden floors quite possible to do on our own using various thermal insulation materials and technologies. The costs incurred will be recouped over several years due to energy savings. Besides, building construction, due to the absence of temperature changes and condensation formation, will receive more a long period operation.

Often a wooden floor is made only from a single board, which is placed along the joists. This design is simply cold. The thickness of one board is 27 - 40 mm, which is clearly not enough to retain heat.

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

There are other features that need to be taken into account to ensure that thermal insulation is effective and durable. How to properly insulate wooden floors in various cases - this will be discussed further.

Wood floor design options

Consider the following designs:

• The wooden flooring is made along the joists above the ventilated underground. There are vents in the foundation, and there is little humidity under the floor. Due to air exchange, the temperature rises in summer and can be lower in winter.
• Wood flooring on joists above the outside atmosphere with pile foundation with a grillage.
• The flooring is made over a wet basement or cellar.
• The flooring is made above the ground without ventilation or laid directly on the bedding along the ground.

Taking ceiling heights into account

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

The optimal range is considered to be between 2.35 and 2.5 meters. If more, then heat loss increases, more energy is needed for heating due to maintenance 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 insulating the floors with another layer on top of the existing ones. But reducing the height to less than 2.35 m is not recommended - the space will become cramped and uncomfortable. In this case, the insulation layer can only be placed under the floor.

What kind of 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 temperate climate above the ground (along the ground) you need about 12 cm of expanded polystyrene or 15 cm of mineral wool.


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

But this will not be critical if the lining is no more than 60 percent of the surface of the log. Another nuance is that foam plastic is difficult to place tightly between the joists; cracks appear that are sealed with crumbs.

What is chosen more often

Expanded polystyrene is dangerous when burned, so there must be a printed-cement or gypsum floor on top of it, at least 3 cm thick, separating it from the living space.

More often, mineral wool in soft mats is used to insulate wooden floors, especially subfloors. It “gets along” well with the tree, and living creatures avoid it.

Cotton wool does not burn, so the construction of 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 joists

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

From below, boards made of plywood, or any other panel material, but perforated, with holes for ventilation. You can use the boards staggered.

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

Mineral wool and logs are covered on top waterproofing membrane. You can also use roofing felt with overlaps of 20 cm. The membrane is rolled onto the wall by 20 cm. Next, the floorboard is laid

If you make a mistake and don’t ventilate

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

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

Draining 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. The joists are installed across the joists of the lower floor, if necessary they are leveled in height.

Mineral wool is laid and must be separated from the living space by waterproofing. Covered with a new floorboard from 32 mm thick. The thickness of the insulation is the same.

You can save money by installing thinner sheathing on pads instead of joists in increments of 0.6 meters, but the pads should well redistribute the load on the subfloor.

Above the cellar, along the ground

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

If it is impossible to provide ventilation, extruded polystyrene foam can be used. When laying, it is important to avoid gaps with joists and between sheets.

The thickness of extruded polystyrene foam can be reduced to 60% of the thickness of mineral wool. But on top the insulation is fenced with fireproof material, possibly between the joists.

Pile foundation with grillage and wooden floors

The fundamental difference is that the outside temperature is under the floor and the wind is blowing. Then, for soft mineral wool mats with a density below 160 kg/m3, a windproof superdiffusion membrane is additionally introduced. It will allow steam to escape from the cotton wool, but will protect the insulation from being blown by a jet with heat loss.

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

Wooden floor on fill or concrete base

Between the floor and the base, which has a ground temperature, there should be a layer of insulation. Typical solution- the use of extruded polystyrene foam with a thickness of 10 cm and pouring a floating screed on top of it.

The floor is one of the coldest parts of the house. This especially applies to the first floors multi-storey buildings, as well as private wooden houses. This is primarily due to the fact that cold air tends to fall down, and drafts also blow from under the floor. Therefore, in order to obtain a warmer floor and reduce heat loss in the house, the floor must be properly insulated. This is especially necessary if the floor of the house is made of wood. Even if the docks were packed tightly together, over time they will dry out and leaks will begin to leak from the crevices. As a result, heat loss in the house can reach 30%. You can insulate a wooden floor with your own hands; the technology is quite simple. However, before insulating a wooden floor, it is necessary to study the properties of various insulation materials.

Floor insulation is an integral part in the construction and renovation of private houses.

Wood floor insulation technology

Before you begin the process of insulating the floor, you need to decide on a number of important parameters, namely: the possible height of the thermal insulation layer and the entire structure, surface operating conditions (indoor conditions - humidity and temperature, load, purpose). Only after you have decided on these parameters will it be possible to properly insulate a wooden house.

The technology for insulating such a floor is quite simple, you can easily handle it yourself. Properly installed thermal insulation consists of a layer of thermal insulation material, a vapor barrier and a floor covering. In the process of designing a thermal insulation layer, you need to determine its thickness. The thickness of this layer depends on climatic conditions and the type of insulation. It is selected individually for each building.

Insulation of wooden floors on joists

Most often, the method of insulation on joists is used to insulate a wooden floor in a house.

Scheme of floor insulation on joists.

It is relatively simple, but at the same time very effective, making it possible to eliminate significant heat loss. This method is only relevant for floors located close to the ground (plinths, first floors).

This insulation technology is carried out as follows. First, wooden logs with a T-shaped notch are installed in the log house or on the foundation in increments of 60-100 cm. Next, you need to secure the boards or panels on which the insulation layer will be laid. Shields (boards) are hemmed from below or secured to special cranial bars. Next, you need to lay insulation on the flooring between the joists.

The next stage is laying a waterproofing and vapor barrier layer. This stage is needed only in certain cases - depending on what material is used for insulation. For example, protection from moisture and vapor is needed in the case of insulation using mineral wool or ecowool. The vapor barrier is overlapped by 10-15 cm, and its edges are bent to a height of up to 10 mm. Ordinary polyethylene film can be used as a vapor barrier material. In this case, the film must be laid so that it goes around each rafter, is in an even state and is secured with staples to the load-bearing elements of the roof. Film is one of the most inexpensive vapor barrier materials. Despite its relatively low cost, polyethylene film copes well with the tasks.

The final stage of insulation on joists is the installation of floorboards and finishing with the selected floor covering.

What is the best way to insulate a wooden floor?

Insulating floors with polyurethane foam is a durable, reliable coating.

You can insulate a wooden floor using a variety of materials. Most often, mineral wool, polyurethane foam, ecowool, penofol, and polystyrene are used for this. You can insulate the floor using sawdust, polystyrene foam and expanded clay. The choice of a specific material depends on many parameters and personal preferences of the home owner.

Insulation of the subfloor is carried out in the same way as for joists. That is, first you need to secure the bars to the sides of the logs, after which you need to lay boards on them using self-tapping screws or nails, which should be cut out in accordance with the distance between the logs. When all the boards are secured and a complete surface is formed, it is covered vapor barrier material. After this, the selected insulation should be laid tightly between the lags, without gaps. Finally, a layer of vapor barrier is laid again. This concludes the work on insulating the subfloor. When using certain thermal insulation materials, a vapor barrier layer may not be necessary.

One of the simplest and available materials, with which you can insulate the floor, are sawdust. Despite its simplicity, sawdust has very good characteristics. The main advantages of this material are its low cost (compared to other types of thermal insulation materials) and ease of backfilling, which allows you to insulate even hard-to-reach and narrow places. As you know, sawdust is obtained as a result of processing natural wood, which means they are environmentally friendly, natural material. Of all materials made on the basis of sawdust, sawdust in its pure form is mainly used for insulating wooden floors.

The most economical and environmentally friendly material for floor insulation is sawdust.

You can insulate a wooden floor using mineral wool, which can be glass, slag or stone. One of the main advantages of this material is its absolute non-flammability. In addition to this, mineral wool has a number of advantages: biological and chemical resistance, fire resistance, high heat and soundproofing characteristics. Among the disadvantages are low vapor permeability and low mechanical strength.

Penofol is one of the modern thermal insulation materials. Penofol appeared relatively recently and is not yet widely used. This is a rolled multilayer material consisting of insulation and a reflective layer, which is thin polished aluminum foil. Almost any insulation material can act as a base (insulating material). The most preferred are translucent materials, which include foamed polyethylene.

Expanded polystyrene is also very popular. This is due to many advantages and an almost complete absence of disadvantages. Such insulation is characterized by low vapor permeability and thermal conductivity, fire resistance, high strength, chemical and biological resistance (does not decompose, does not undergo mold formation, and is not afraid of rodents). The cellular structure of the material makes it durable and very effective as thermal insulation for wooden floors.

Penofol - modern material for insulation. It is thin, lightweight, and has high thermal insulation properties.

You can insulate a wooden floor using ecowool. This material consists of 80% cellulose and 20% various natural additives. Organic antiseptic lignin and boric acid. It is due to this composition that the main advantage of ecowool is determined - its environmental friendliness and complete safety for humans.

Polyurethane foam is obtained by synthesizing two components - isocyanate and polyol components. By changing the recipe and processing mode, you can achieve various materials: from plastic and soft to hard, differing in density and physical and mechanical characteristics.

How best to insulate a floor: stages of work

To properly insulate a wooden floor, you need to have a number of tools and accessories on hand. Some of them will be used constantly, while others are needed occasionally. You will need:

To insulate the floor you will need a level, drill, screwdriver, saw, tape measure and pencil.

1. Drill for drilling various holes.
2. Level - length at least 200-250 cm.
3. The rule is a special rail made of metal or wood, the length is from 120 to 200 cm.
4. Mixer - equipment for mixing various compositions.
5. A screwdriver is a device for tightening various fasteners.
6. An electric jigsaw is a device that automates sawing work.
7. Ordinary saw.
8. Roulette.
9. Chop.
10. Pencil.

The process of insulating a wooden floor may vary slightly depending on what material was chosen as thermal insulation. Next, the most popular and widespread method will be considered.

Chipboard is very often used as flooring, which can be explained by its relatively low cost and fairly high quality.

Scheme of insulating floors in a house with penofol and penomplex.

Laying on the foundation or strapping is carried out waterproofing material(roofing felt). This material is needed so that the sand does not absorb water and other liquids that can get into it from the foundation. The sand layer itself should not be too large.

Leveling the sand cushion can be done with almost any available means, for example, using a shovel or rake. Next, polyethylene film is laid. Much attention should be paid to its thickness. Actually, the thicker the film, the more efficient system will cope with the tasks assigned to it.
Polyethylene film is attached to the base. A construction stapler is used for this.

The next step is flooring foam (or laying another material of your choice). This material is excellent as thermal insulation. Firstly, it retains heat remarkably and provides high noise protection. Secondly, this material is not dangerous to human health, it does not ignite and is characterized by chemical inertness.

Make sure that no extraneous holes remain after installation. All cracks must be eliminated without fail.

The final stage is creation last layers in the amount of two. The layers are made from chipboard. That's all, the process of insulating a wooden floor in a private house is over. In reality, any construction works look simple and easy only on paper. However, if you strictly follow the instructions given, then you will definitely succeed.

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