Insulate the subfloor. Features of insulation of floors of wooden houses. Pile foundation with grillage and wooden floors

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 often use bulk materials for floor insulation: expanded clay, perlite, polystyrene foam balls, ecowool, tyrsa, straw, derivatives or wood waste (sawdust, shavings, wood pellets).

In the second option, support columns or strips of brick (concrete, rolled steel, foam concrete blocks with an average density of at least 400-600 kg/m3) on a pre-prepared sand cushion can act as a base. Insulation for floors wooden house is placed at a certain distance from the ground surface, forming a ventilated space (subfloor) to remove moisture. In this case, it is more convenient to construct a thermal insulation barrier by laying slab (expanded polystyrene, wood concrete 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, large construction waste, broken brick, etc. 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 levels, it is recommended to raise the frame structure, including floor insulation on joists, 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, then it is recommended to install them 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 at various levels, not only from moisture, but also the migration of soil radon gas into the living space is 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 pitch between the lags depends on the rigidity of the entire structure: the material used for floor insulation, the thickness of the lag, the type of 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 fasten a metal mesh along the bottom plane of the logs. If you chose bulk heat insulator, then you will have to assemble a lower subfloor to support it. OSB boards, substandard boards, plywood scraps, etc. are suitable for it. 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 humid 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 tape intended for such work;
• 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 arrange the insulation of the subfloor from building materials made using wood waste. Similar products include:

• 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, highly resistant to combustion and biological damage;
• sawdust concrete, for the production of which, in addition to sawdust, mainly coniferous species wood, sand is used as a fine filler, and Portland cement is used as a binder. The finished product is molded into 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 the fibrous material will be enclosed in a rigid structure of logs and plank flooring.

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, an organic binder (lignin), an antiseptic and a 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 using 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 makes it possible 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! Between the reflective layer and inner surface floor covering should maintain a distance of 10-20 mm.

6. Spray polyurethane foam

Polyurethane foam has a cellular structure, reminiscent of very dense extruded foam. It is one of the most effective means of thermal insulation due to its 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

The insulation of wooden floors can be done on your 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 a longer service life.

Cold winters still exist, and you need to prepare well for them so that living in your home is 100 percent comfortable. Warm floors are the basis on which it depends how pleasant it is to be indoors when it’s cool outside. There are convenient options for insulating this part of the building without removing the top layer - it’s easy to do yourself if you follow simple recommendations.

We insulate floors from the basement - when is it advisable?

Any wooden house quickly loses heat, this is due to the nature of the material. Therefore, insulation of all parts related to the external environment is mandatory. Walls are only part general design, which must undergo a thorough heat blocking procedure. The process of working with the floor will solve problems such as:

• excessive energy consumption for heating the room;
• high humidity – important for transitional seasons;
• rotting of wooden building elements;
• the appearance of fungus and mold, which poses a danger to the health of the residents of the house.

Most often, cottages have insulated floors above a cold basement, because... in the cold season, they quickly cool down and have a low temperature even if the room is heated using its boiler system. Poor thermal insulation or its absence means icy floors on which it is useless to lay carpets. The problem can only be solved by proper insulation; there are simple techniques that can be used without removing the old floor. It is better to spend money once on such an event than to constantly spend extra gas or electricity on double heating of rooms.

In the event that the building has already been built and there is a need for additional insulation floors, it is more expedient to do this from below, i.e. without removing floor coverings. Advantages of the lower technique:

• The ceiling height in the rooms will remain the same, because... there will be no need to raise the floors due to insulation;
• there is no need to specifically spend money on insulating compounds of increased density and rigidity due to the load of furniture, appliances and other items in the house;
• you will protect not only the floor itself, but also all floor structures from freezing, which will extend their service life and generally make your home warmer;
• there will be a change in the location of the dew point from the inside to the surface of the ceiling - this will help get rid of rotting of wooden elements.

The method of insulating the floor from below has only one limitation - the subfloor is too low, in which it is impossible to be in for work. Such cottage buildings are quite rare. If this is your case, choose the option of insulating the floors from above, i.e. with the procedure for opening it and filling it with suitable insulating material.

Mineral wool - fiber insulator

Mineral wool is construction insulation, consisting of many fibers, presented in three separate types: glass; stone or basalt; slags For working with the floor, basalt cloth is preferable, because... it is easiest to install under the floor structure. Of the two options - rolled and mats in the form of slabs - choose the second one, because... it holds its shape well. Advantages:

• good level of thermal insulation;
• simple installation technology;
• relatively low level of perception of moisture from the environment;
• reasonable price;
• heat resistance and fire safety;
• The material does not harbor bacteria, mold or mildew.

Flaws:

• When laying with your own hands, you must use special protection - gloves, clothing, a respirator, glasses, because... there will be many particles of fibers and dust in the air, causing irritation to the skin and respiratory system;
• protection from moisture is required, because the structure is susceptible to vapor absorption;
• If installed incorrectly, severe shrinkage may occur;
• when laying between the joists, you need to leave a gap of 5 centimeters to the main structure.

If you decide to choose mineral fiber, select the material required thickness. Specific data depends on the climate zone, e.g. middle zone An indicator of 100-150 millimeters is suitable for Russia. Basalt wool is suitable for all types of floors, including attics.

Polystyrene foam - airy material made from granules

Polystyrene foam consists of foamed PVC granules containing a maximum of air inside, this gives it good thermal insulation qualities. Advantages:

• has strength, stability, rigidity;
• almost does not absorb moisture - the percentage is lower than that of mineral mats;
• is light in weight;
• easy to install, because does not change shape;
• inexpensive;
• durable, does not mold, does not rot.

Flaws:

• susceptible to fire;
• fragile to break;
• Base ventilation is required, because does not allow steam and air to pass through.

For insulating floors in an ordinary private house, foam boards of the PSB-S-15 brand ten centimeters thick are suitable. When purchasing, do not confuse them with granulated polystyrene foam, which easily crumbles into small PVC balls. The latter can also be used as insulation if the renovation budget is very small. The material has good thermal conductivity, but has a relatively short service life - no more than ten years.

Polyurethane foam - do you need a device to work with it?

This building material consists of two types of foam - light and hard. To work with the floor, the second option is used, because it does not require special vapor barrier on the basement side and has the best thermal insulation characteristics. The first type is very similar to mineral wool - in the same way, when working with it, you will have to leave gaps for ventilation and waterproof the lower surface. PPU consists of two components:

1. 1. polyol or hydroacid with emulsifiers, polyesters and reagents responsible for foaming;
2. 2. isocyanate or polyisocyanate and diphenylmethane diisocyanate mixed with each other, which are strong reagents in combination.

Advantages of the building material:

• fills all cracks and corner spaces thanks to spraying technology;
• suitable for installation from below;
• does not shrink, is fireproof;
• does not require protection from vapors;
• durable - lasts up to 50 years;
• high level of adhesion to all materials;
• high installation speed;
• complete environmental friendliness;
• has no seams, because represents a single canvas after drying.

Among the disadvantages are the high cost, the need for skill in application and the use of special equipment - a high-pressure apparatus, which can be rented.

Installation technology - how to preserve heat quickly and efficiently?

Mineral wool and polystyrene foam, in the form of slabs, are mounted on the “wrong side” of the floor from the side basement using the same technology. Attach bars with a cross-section from 50 to 100 millimeters to the rack-beams from below. Place a layer of thermal insulation material on top, like on shelves. The beams should be located under the “top” floor at such a distance that there are a few centimeters between it and the top surface for ventilation. Hem the bottom of the heat-insulating “pie” with boards, apply waterproofing to prevent vapors from penetrating into the material from the basement.

The waterproofing function can be performed by ordinary polyethylene film - this is the cheapest and convenient option. A moisture-proof membrane will cost more - it is stronger and does not prevent air movement, unlike cellophane. In order for the materials to last longer, the top surface of the main thermal insulation will need to be covered with film. The order of all layers from top to bottom will be as follows:

1. 1. flooring;
2. 2. concrete screed or expanded clay;
3. 3. overlap;
4. 4. vapor barrier from the side of the room;
5. 5. a layer of mineral wool or polystyrene foam;
6. 6. waterproofing from the basement;
7. 7. holding boards.

The application of polyurethane foam is carried out on a specially prepared floor surface; it is necessary to remove dust and debris from it and make sure that it is completely dry and free of grease. Foam does not adhere to polyethylene and fatty compounds. The procedure can be carried out at temperatures above 10 degrees, otherwise the material will not stick to the ceiling as it should.

To work, you will need a high-pressure apparatus - it is very expensive to buy, you can rent it from specialized companies. It is connected to two containers with the first and second components. When you press the start button, the compositions are combined in a vortex chamber, then they are sprayed in the form of a small and light mass. The pressure in the car must be at least 140 atmospheres. When choosing equipment, pay attention to the current source - the required one must match your home network.

Apply polyurethane foam evenly, after putting on protective equipment– glasses, respirator, gloves. The procedure to perform it by a professional takes about an hour, if you are confident in your abilities, you can try it yourself, but it will take more time due to insufficient experience. Apply polyurethane foam not only to the space between the joists, but also to the joists themselves - this will protect them from rising steam from the ground.

After applying a layer of about 10 centimeters, turn off the device and leave the room to dry. Complete hardening of the material and its ideal adhesion is achieved in two days. There is no need to specially treat the bottom layer, because it is not exposed to moisture and holds well to the top of the floor.

P Before thinking about how to insulate a wooden floor in a house, you need to decide exactly what problems you intend to solve with this, and at the same time think about what problems may arise as a result. Otherwise insulation of wooden floors in the house may turn out to be not only unnecessary, but also harmful. Especially if the problem is being solved insulation of floors in a wooden house.

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Design and operating features of a wooden floor

To better understand what you have to deal with, let's look at the construction of a wooden floor.

The basis for it is wooden beams, the so-called “logs” (these floors are sometimes called “”). Milled boards are placed on the logs in a special way, forming a finishing coating, or a so-called “rough” floor made of unplaned or even uncut boards, artificial materials (plywood, chipboard, OSB). The subfloor serves as the basis for and similar coatings.

An important factor in the normal operation of wooden floors is proper ventilation of the floor from below, that is, under the plank covering and between the joists (ventilation of the space under the floor covering). If ventilation is insufficient, over time due to high humidity the tree is affected by a fungus, and the created microclimate promotes the appearance of various insects, including wood borers.

For good air circulation, special gutters are even installed on the floor boards below (see Fig. 1).

Places where you need to insulate a wooden floor

Experience in the operation of buildings suggests that for effective thermal insulation, it is necessary first of all to protect the junction of the floors with the external walls.

If we are talking about floor insulation in apartment building, often the entire surface requires insulation. For example, below there is an unheated basement, the temperature in which in winter, although maintained above zero (otherwise the sewerage and water supply would freeze), is lower than in the apartment. And a difference of even five degrees is already noticeable heat loss.

Observations, design standards and ordinary common sense will tell you how to insulate a wooden floor exactly where it is needed.

As for how to insulate the floor in a wooden house, it’s more complicated. A wooden house can be chopped and framed, made of timber, or log. Lined and not lined. All these options make their own adjustments. Therefore, in this article we will try to give general principles, and in each specific case, based on them, you need to think through what and how to do here and now.

The insulation is poured or laid between the joists, and there must be at least 4-5 centimeters of gap between the top of the insulation and the bottom plane of the covering for normal ventilation of the subfloor.

Before laying the insulation, it is necessary to lay an insulating carpet that cuts off vapor or liquid (osmotic) moisture (if the base is soil). Using mineral wool insulation a hydraulic barrier is additionally installed on top. That is, a warm “pie” is created into which it is difficult for moisture to penetrate, but from where it easily evaporates through the vapor-permeable waterproofing.

If foam plastics are used for insulation, steam and waterproofing are not done, and the seams between individual slabs, between the insulation and joists (walls) are filled with polyurethane foam.

When insulating the floors of the first floor, when there is soil below or the ceiling of a warm basement, it is enough to lay thermal insulation at the junction of the floor and external walls, making a belt 80-100 centimeters wide. The purpose of the belt is not to insulate the wall, but to provide thermal insulation from the side of the soil, which freezes in winter (see Fig. 2).

Tools for floor insulation in a wooden house (wooden floor)

Insulating a wooden floor in a house does not require a significant set of tools. Cutting of foam insulation and vapor and waterproofing films is carried out assembly knife and regular scissors. When working with mineral wool, a knife (rigid and semi-rigid slabs) and large scissors (soft roll insulation) are also used.

Of course, if an already assembled structure is insulated, carpentry tools are required. However, this has a rather indirect relation to the issue of insulation.

In conclusion about the insulation of a wooden floor

So, we have looked at how to insulate a wooden floor. As already mentioned, the question of the need for insulation arises in two cases:

New construction;
shortcomings of the existing floor.

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Natural wood is one of the best building materials. It is environmentally friendly and high performance characteristics, but requires appropriate care. So just won't be enough. It is necessary to carry out a number of mandatory accompanying measures, among which one of the most important is floor insulation. It’s not difficult to figure out how to insulate the floor in a wooden house. You just need to strictly follow the instructions, and you will not only make your home more cozy and comfortable, but you will also be able to reduce heat loss, significantly save on heating and extend the life of the building.

What materials can be used for insulation?

Before insulating the floor in a wooden house, you need to choose the appropriate material. The modern market offers a large selection of different solutions with a wide variety of characteristics. Currently, you can insulate a wooden floor using the following materials:

When insulating with mineral wool, it is placed between the load-bearing elements of the frame.

• isolona;
• mineral wool;
• expanded polystyrene and polyurethane foam;
• penofol;
• ecowool.

The simplest and budget material, with which you can insulate the floor, is sawdust. One of the main advantages of sawdust is that it can be poured even into the most inaccessible places where it is impossible to install other existing insulation materials. In addition, sawdust is a wood processing product, so the floor of a wooden house protected by this material will be completely environmentally friendly.

No less popular and accessible material with which you can insulate the floor in a wooden house is mineral wool and its varieties. Such insulation practically does not support combustion, it is resistant to biological and chemical influences, has good sound and heat insulation properties. However, if you decide to insulate the floor in a wooden house with this material, then keep in mind that it absorbs moisture well, while losing its insulating characteristics. Therefore, it is very important to arrange high-quality waterproofing on each side of the insulation. Among other things, mineral wool is characterized by relatively low strength and is not always safe for human health. Mineral wool contains phenol-formaldehyde resins - a very toxic substance. So if you have a more or less decent budget, then it is better to insulate the floor in a wooden house using other materials.

Mineral wool is sold in the form of a flexible mat or slab. The sides of the slab usually have different hardnesses. The one that is harder is marked with a blue stripe. If you insulate the floor in a wooden house with this material, remember that it must be laid with the blue marking strip facing up.

Izolon is a non-flammable material resistant to chemical and biological damage. It is made from mineral fibers, but has a much higher hydrophobic ability and low thermal conductivity compared to ordinary mineral wool. The floor in a wooden house, protected with such material, will always remain warm. Rockwool has similar properties, but higher resistance to mechanical damage. This insulation, made on the basis basalt wool, is also a very good sound insulator.

Expanded polystyrene is a very durable and moisture-resistant material. It has a long service life and good thermal insulation properties. The material is not interesting to rodents and insects. It is safe for humans, very easy to install, retains its original volume well and maintains its shape.

Scheme of a floor insulated with ecowool: 1-finish floor; 2.5-kraft paper; 3-lags; 4-ewool; 6-rough floor.

When choosing the material with which you will insulate the floor in your wooden house, pay attention to its service life. Understanding which of the available materials is the most durable is not so easy. For example, some insulation materials are not able to maintain their original shape and volume for a long time.

During operation, they become deformed and begin to loosely adhere to the floor boards and joists, resulting in the formation of cold bridges and condensation. Therefore, it is better not to insulate the floor in a wooden house with such materials.

Checking the quality of thermal insulation is very simple. In the process of selecting it, you just need to step on a small area of ​​the material with your foot. If it has returned to its original form, you can safely use it to insulate the floor in a wooden house. If the area does not recover after the applied load, it is better not to use such material.

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Preparing for laying insulation

First of all, you need to prepare the tools with which you will insulate the floor in a wooden house. You will need the following:

• hacksaw;
• drill;
• level;
• set of drills;
• plane;
• hammer;
• roulette;
• screwdriver;
• construction knife.

The floor in a wooden house is insulated in the following sequence:

1. First, a surface is created from slabs or boards. Vapor barrier and moisture protection are installed along it.
2. Wooden logs are installed.
3. Insulation is being installed.
4. The finished floor is being installed.

The floor in a wooden house is insulated quite easily. You just need to strictly follow the instructions. First of all, delete the old one wood covering and correct existing defects. The next step will be installing the subfloor. Thanks to it, the required frame rigidity will be ensured. It also allows you to prevent the occurrence of distortions during the use of floors in the house for their intended purpose.

In most cases, the subfloor in a wooden house is created from coniferous slabs. The boards need to be tightly fitted to each other. Before installation, be sure to treat them with an antiseptic. If this is not done, then after 5-6 years the untreated boards and joists will rot. Most often, boards with a width of 12-15 cm and a thickness of about 5 cm are used. Screws or nails are used to fix the boards.

A fine-mesh metal mesh is laid on top of the rough flooring, which will protect the insulation from rodents. Sprinkle the mesh with expanded clay or coarse sand. A layer 3-4 cm thick will be enough. The powder will not only press down the protective mesh, but will also create sufficient ventilation of the subfloor. This will protect it from damage by fungus and mold.

Regardless of what kind of insulation you use, you must provide waterproofing.

To do this, you can put PVC membranes, roofing felt or ordinary plastic film on a layer of powder. All these materials do an excellent job with their assigned functions.

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Step-by-step instructions for insulating joists

The most popular and effective way floor insulation in a wooden house is a method of thermal insulation along joists. It can significantly reduce heat loss through the floor in a wooden house and is easy to do with your own hands. This method is well suited for those floors that are located close to the ground.

First of all, you need to select optimal thickness layer of thermal insulation. This value depends on what kind of insulation will be used, as well as on the climate in the region where the zone is located. For each specific building, the layer width is calculated individually.

Warming is carried out as follows. First, wooden joists are laid on the waterproofing film. They attach to subfloor using screws or nails. The pitch between the fasteners is no more than 80-100 cm. Insulation is installed in the space between the joists.

If thermal insulation is used in the form of slabs, they must be laid close to the joists. There should be no voids left. Insulation can be laid in 1 or 2 layers. The top needs to be covered with a vapor barrier material. Lay the film overlapping by 10-15 cm. Attach it to the joists with a construction stapler.

To create a finished floor, use special milled wooden boards. They need to be secured to the installed joists. Typically, when producing such boards, the manufacturer provides the possibility of fastening them together with a tongue-and-groove connection. In most cases, boards 4-5 cm thick are used. They must have the same thickness. The width of the boards is about 10-13 cm. As a rule, there is a longitudinal recess on their back side, which greatly facilitates the process of installing the flooring and ensures the necessary air circulation under the boards.

Do not lay the boards close to the walls, leave a gap of 1-1.5 cm - in the future it will be covered with a plinth.

Currently, environmentally friendly low-rise construction of houses from wood materials. Traditional log houses made of rounded logs, cottages made of timber and even houses built from lightweight materials, their owners try to sheathe them with boards or clapboards. To create a microclimate in the home that is closer to nature, the same considerations are used when choosing materials for floors, giving preference to wood as a lighter, but quite durable material.

Due to its natural origin, wood has a fairly low thermal conductivity, but in the Russian climate it still requires additional thermal insulation.

Options

There is a fairly large selection of fillers for insulating interfloor ceilings, floors and ceilings. It can be difficult for an inexperienced builder to understand the properties of this or that insulation, objectively evaluate their advantages and disadvantages, and make the right choice.

The thing is that different heat-insulating materials are more suitable for some operating conditions and less suitable for others. Insulation of such specific rooms as an attic, underground, or veranda requires a special approach, so it is worth studying all the properties of the materials in order to produce insulation as efficiently as possible.

The choice of thermal insulation material is influenced by the following factors:

• Humidity. Constant dampness in the room (basements with open ground or insufficient waterproofing of the foundation, bathrooms, winter gardens or home greenhouses) or the likelihood of increased humidity in it (balconies, rooms for drying clothes, bathrooms or steam rooms);
• Purpose of the premises. Some types of materials contain certain resins or glues that, for safety reasons, are not suitable for bedrooms or children's rooms.
• Possibility of damage by rodents or insects, resistance to fungal attack. Some of the materials are liked by rodents, while others are repellent to them.
• Lower and upper temperature limits. Some heat insulators are not resistant to severe frosts, while others lose their properties or become completely deformed and become unusable when subjected to significant heating.

It should be borne in mind that the heat-insulating material must “work both ways” - not only protect the home from low temperatures in winter, but also to maintain a comfortable environment for people and pets in the summer heat.

Last but not least, the choice of insulation and the method of performing thermal insulation are also influenced by the general condition of the house:

• age of the building - an old house requires one method, a recently built one requires another;
• foundation construction method - on bored or screw piles, on reinforced concrete blocks or on lightweight shallow foundations;
• the number of storeys of the building and the area where the work will be performed - whether the floor insulation is being carried out for the 1st or 2nd floor.

From below

In most cases, wooden houses are built with a high base, that is, the height of the subfloor allows for insulation from below. The only exception may be the southern regions, where private houses are being built on stable soils using the technology of constructing low-rise buildings on shallow piles. But even there, in most cases, they try to adhere to the traditional construction of houses with a high base.

Otherwise, if the subfloor is not high enough, to insulate the floor of the first floor you will need to remove the floor board to the joists or other supporting structure.

Thus, it is possible to insulate from below with a sufficiently high subfloor for the first floor or insulate the floor of the second floor, which, accordingly, is the ceiling for the first floor.

Carrying out thermal insulation work in the underground is not much more complicated than the same work when insulating the floor of the second floor, but it has a number of features. Before starting work, you need to prepare the place and provide yourself with both minimum comfort and the necessary level of safety.

Most likely, there are no windows in the basement, so first of all you need to take care of sufficient lighting. If there are no stationary lamps, Waterproof portable light sources with a flexible cord of sufficient length should be used.

For the same reason, there is extremely poor natural ventilation in the underground space, and sometimes it is completely absent. Unfortunately, many builders do not take this factor into account, which has an extremely negative impact on labor productivity. Exhaled carbon dioxide is heavier than other gases that make up atmospheric air, and therefore tends to the bottom.

And since the underground is the lowest point, carbon dioxide accumulates here, disrupts the worker’s full breathing, causes increased fatigue, drowsiness and, in especially severe cases, fainting. That's why it is very important to ensure sufficient supply ventilation from inside the house or from the street.

Of course, while work is being carried out in the basement, it is necessary to remove all things, food and other objects stored there that interfere with the unhindered movement of the repairman.

If in the underground open ground, if possible, it should be leveled and compacted. In the best case, if the budget allows, pour concrete to a minimum height of 10 cm with reinforcement, thereby significantly reducing the humidity in the underground space. This will significantly extend the service life of both the load-bearing elements of the plinth and the wooden floor structures.

In the absence of natural passive ventilation of the subfloor, it would not be a bad idea to external walls small (about 10*10 cm) ventilation vents. This will improve the microclimate in the cellar, additionally prevent an increase in humidity and, as a result, avoid damage mold fungus wooden structures.

Having finished preparatory work, first of all, you need to check the condition of the load-bearing elements - beams, joists, support posts.

Having identified areas of mold damage, thoroughly clean the surface with a spatula, sandpaper(popularly called “skin”), then soak twice with antiseptic solutions. Then soak all accessible wooden elements generously with fire- and bio-protective compounds and dry thoroughly.

If the foundation and plinth are built using concrete or brick (block), these areas need to be treated bitumen mastic for protection against moisture. If work is carried out on days of high atmospheric humidity, it may be necessary to additionally dry them using heating equipment.

In some cases, a conventional household fan heater will be sufficient, but for large underground spaces, a construction heat gun may be required. In no case Do not use a gas or gasoline/diesel heat gun, it is permissible to use only an electric one, and it should not be left unattended for safety reasons.

For insulation from below, it is quite inconvenient to carry out work with rolled heat-insulating materials, such as mineral wool or isolon. Moreover, they are not suitable for these purposes. bulk materials– sawdust, expanded clay and the like. Therefore, preference should be given to insulation in sheets - penoplex, polystyrene foam, and so on.

First of all, you should fix the vapor barrier material, in most cases it is plastic film. For underground conditions, it is preferable to choose a film with a thickness of 350 microns, if possible even denser.

It must be secured, ensuring complete adherence with a construction stapler along the joists (beams), taking into account all irregularities, bends and height differences; in places where it sags, additionally secure it along the floor boards. The film fragments must be laid with an overlap of at least 10 cm over one another, and the edges must be secured with wide adhesive tape. Overlap on the walls and vertical structures– at least 25 cm.

After this, you need to begin installing heat-insulating material in the gaps between the joists. If possible, the fragments of the insulation should be cut so that there are no unnecessary gaps between them and the joists, and the insulation itself does not fall out. If necessary, if the fragment does not hold onto the joists with its edges, it can be temporarily secured with self-tapping screws, and the gap between its edges and the joists can be filled with polyurethane foam.

It should be remembered that metal self-tapping screws have a very high thermal conductivity, so after the construction foam has hardened, they all need to be removed.

Also, after laying the heat-insulating material over the entire surface of the ceiling, all gaps that inevitably arise must be filled with polyurethane foam, and after it has hardened, the protruding excess must be cut off.

After this, to ensure more reliable retention of the heat-insulating material, you need to secure it from below with a light hem. Most economical option- fiberboard sheets, but low-grade plywood, edged boards and a number of other materials are also suitable. You should not use gypsum plasterboard ( plasterboard sheet) due to its high hygroscopicity and fragility.

After completing the filing, you should attach another layer of vapor and waterproofing. You can also use plastic film. IN in this case It is permissible to use isolon, folgoizol and other composite materials.

Above

In this case, there are two options for insulation, fundamentally different from one another:

• Without dismantling the floor covering. Logs are laid on the old floor, insulation is placed between them and a new floor covering is placed on top.
• With dismantling. In this case, the boards are marked, dismantled and removed from the room where they are being repaired. The insulation is installed between the existing joists, then the floor boards are installed back.

In the first case, the floor level is raised - depending on the technology used, by a height of 10 to 25, and in some cases by 30 cm. This method is economically more expensive and reduces the usable volume of the room. But if the budget allows and the ceilings are high enough, this option can significantly reduce the time it takes to complete the work.

In the second case, the floor height remains at the same level, but more labor and time will be required from the builder.

Whatever option is chosen, before starting all work, you need to remove all the furniture from the room, clear the floor of carpet or other covering, and remove the baseboard.

First you need to check the condition of the floor boards. Elements damaged by rotting or affected by mold must be replaced, unstable ones must be fixed. On old boards you need to apply primer, antiseptic impregnation and dry, if necessary, use additional sources heat.

As when inspecting the underground space, areas affected by fungus, but remaining strong, must be cleaned down to healthy wood and generously soaked with antiseptics.

Experienced builders recommend for these purposes using a composition that is practical and completely safe for humans and pets, but so unloved by rodents and wood-boring insects - cool solution of ordinary table salt. To prepare it, add salt to hot water until it stops stirring.

The areas of the board that have been previously cleared of mold from the outside are thickly spilled with a hot saline solution. Any gaps or cracks found between the boards must be filled. construction foam, level the top with oil-based putty or acrylic base. After drying, lay a waterproofing material - plastic film or penofol, and glue the joints with wide tape.

After this, the logs are laid. You should choose a timber made from coniferous wood, the minimum cross-section of which is 50*50mm. However, if the floor of the lower floor is insulated and enhanced thermal insulation is required, then, accordingly, a beam of a larger cross-section is required.

Preferably dried timber without visible deformations (without bending along any axes), chips or other damage. It is important to take into account that there should be a gap of 1 - 2 cm between the insulation and the top board for natural microcirculation of air and humidity compensation, therefore the height of the material for the logs must be calculated with a margin.

As a frame, in addition to timber, it is permissible to use edged board from 50 mm thick of the appropriate width, installed on the edge (the wider side will be located vertically) - in this case, a more rigid fastening of the boards to the floor is required. You may need metal corners with a shelf length of at least half the width of the board: for example, if a board with a cross-section of 50*120 mm is selected for installation on an edge, then the length of the shelf metal corner must be at least 60 mm. The installation step of the corners is no more than 1 meter.

It is strongly not recommended to use unedged materials, since larvae or even adult individuals of wood-boring insects can remain in the wane (remnants of bark) on the wood, and, unfortunately, it is not always possible to eliminate them with the help of bioprotective impregnations.

Laying should begin from the highest area selected using a building level. The lag laying scheme is quite simple. The step must be kept constant - from 50 to 60 cm. It should be kept as horizontal as possible, if necessary, placing hard inserts resistant to moisture and fungus underneath. The logs are attached to the floor with self-tapping screws in increments of 100-120 cm.

Heat-insulating material is placed in the space between the joists. When insulating from above, the choice is no longer limited to sheet insulation. In this case, it is possible to lay plywood of sufficient thickness on the floor rather than boards, then the floor will last even a little longer.

DIY work algorithm

Insulation from above with the dismantling of floor boards implies that the floor boards have been checked, their condition is satisfactory and they do not need to be replaced.

Before dismantling, the boards must be marked, indicating their order and orientation, since in the case of using tongue-and-groove boards or with a tongue-and-groove fastening, an error in orientation will disrupt their mutual fastening. The top side will be indicated by the surface on which the marking is applied.

Dismantling must be done with the utmost care, without damaging the material. If the boards are fastened with self-tapping screws, they all need to be unscrewed and only then lifted one at a time, starting from the edge of the room.

Old paint can create some difficulty when finding fastening points with self-tapping screws if the floor has been painted. This will help simple way– use of a magnet, possibly from an old speaker (speaker). Although today a more powerful neodymium magnet is relatively inexpensive. Use it to find the head of the screw, use a spatula to remove the paint, and unscrew the screw.

Dismantling is performed a little differently if the boards are nailed. Under no circumstances should you try to remove nails with pliers or a nail puller; this will only lead to damage to the board. Nail heads can also be easily found with a magnet; these places are marked with a marker.

Builders of the “old school” use an ax to dismantle boards: they carefully wedge it between the joist and the board, without damaging either one, and lift the edge of the board with a slight rocking.

You can use a pry bar or a flat-tipped nail gun. There is no need to try to lift the entire board at once, wedging it with an ax in only one place, as this may cause the wood to split.

Raise the board at each attachment point on small height, then walk along the board again, repeating this operation. When the edge is already noticeably raised, place additional support under the tool and lift the entire board. Wherein It is important to ensure that the tongue or tongue of the board is not damaged.

Old nails need to be knocked out with a hammer from the point side, and when the nail head rises above the board, remove it using tongs or pliers. Having removed the boards, the builder opens the logs and, if their condition is satisfactory, lays plastic film using construction stapler, fastens the joints with tape and installs heat-insulating material.

In both cases, with open joists, they should be impregnated with fire and bioprotective substances and thoroughly dried before laying the insulation.

If bulk material is used - be it sawdust, wood concrete granules, expanded clay or any other, it is necessary to carefully level the layer of insulating material, avoiding too loose laying or, conversely, excessive compaction, and fill all irregularities and cracks. In case of use roll materials you need to try to cut in accordance with the geometry of the space between the joists, avoid tears and creasing, and do not leave voids.

It should be remembered that many rolled heat-insulating materials, when wet, lose their properties and turn from a heat insulator into a heat conductor. When working with sheet material, you should try to cut as accurately as possible, avoid bending the sheets, fill gaps and voids with foam.

Upon completion of laying the heat insulator, regardless of how hygroscopic the material is, you should again lay polyethylene or other moisture-proofing film, and after that install the boards.

Materials for thermal insulation

The modern market offers enough wide choose materials for thermal insulation, and it can be difficult for an inexperienced home craftsman to choose the most suitable insulation for a wooden floor.

In addition to price, each type of material has its own advantages, and some have obvious disadvantages:

• Penoplex. Sheet insulation, produced in a fairly wide range of thicknesses. Quite durable and at the same time easily processed material with high heat-insulating characteristics, resistant to moisture and mechanical stress. For ease of installation, it is available in a tongue-and-groove version. Afraid of high temperatures and organic solvents. Unattractive to rodents and insects.
• Styrofoam. Unlike its older brother - penoplex, it is softer, less resistant to moisture, and can crumble when cut. At the same time, it has a much lower density and, as a result, a slightly greater thermal insulation ability. Unlike penoplex and EPS, it does not contain styrene, that is, it is somewhat safer when used in living rooms.

• EPPS– extruded polystyrene foam. Essentially, this is the same penoplex, but with slight differences in production technology. In terms of characteristics, it is in no way inferior to or superior to it.
• Sawdust. This bulk material is very cheap, in some cases even free, since it is actually a production waste. One of the most environmentally friendly and safe materials for humans and pets. It should be remembered that sawdust cannot be laid in its pure form, otherwise an invasion of rodents and insects cannot be avoided. Sawdust must be mixed with cement or clay, and fire retardant, antiseptic and antifungal solutions must be added. Sawdust is intolerant to dampness and, without proper treatment and moisture insulation, is easily susceptible to rotting and mold. Over time they cake, losing their insulating qualities.
• Expanded clay. Light porous bulk material made of baked clay, which is why it is absolutely harmless. Resistant to high temperatures. Expanded clay does not have closed pores, which is why it is hygroscopic and requires high-quality waterproofing.

• Penofol. It is foamed polyethylene with aluminum foil applied to one side (less often on both sides). It has high moisture resistance and is noticeably inferior to foam plastic in terms of thermal insulation characteristics. Very sensitive to even slight heat. Not damaged by fungus, not susceptible to rotting. When using, one feature should be taken into account - the foil side should be facing the warm room.
• Izospan. High quality material for vapor and waterproofing. Used as moisture protection, it allows wooden structures“breathe”, that is, does not interfere with air exchange with the environment. Flammable Resistant to fungal attack.
• Izolon. Foamed polyethylene without foil. Due to the nature of production, it is not produced in thicknesses greater than 7 mm, therefore it does not serve as a heat insulator. practical application. At the same time, this is a high-quality waterproofing material with some sound insulating properties. Sensitive to high temperatures, resistant to fungus, not damaged by rodents or insects.

• Ecowool. Extrusion material based on cellulose. Rarely used in private housing construction, since application requires specialized equipment and trained personnel. Unfortunately, it is not uncommon for a contractor to, in order to reduce costs, violate the recipe of the original composition, as a result of which this material with high thermal insulating characteristics over time begins to evaporate toxic substances into the environment.
• Polyurethane foam, like cellulose ecowool, requires specialized equipment for application. No harmful substances are used in the composition. When cured, it forms closed pores, which eliminates any evaporation of substances into the environment. It is not subject to recipe violations on the part of the contractor. Frost- and heat-resistant, not susceptible to rotting, mold, or fungal attack. It has high noise and heat insulating characteristics.
• Mineral wool. One of the most undemanding and easy to use heat-insulating materials. It is afraid of moisture, but after drying it restores its properties. Thanks to the filling with mineral chips, it eliminates damage by rodents or insects, and the absence of organic fillers prevents rotting or mold damage. Easily wrinkled material, therefore requires careful handling

When choosing an insulating material, be sure to read the instructions for use attached to it. This document describes in detail the characteristics: thermal conductivity, permissible temperature range, humidity, and so on.

Typical errors

In some cases, builders, relying on the moisture resistance of the material declared by the manufacturer, neglect additional waterproofing. With sudden changes in temperature in the environment high humidity Condensation may form, just like when water flows directly from the room through cracks in the floor. When water freezes, it causes cracking or rupture of pores in the material, which sharply reduces the thermal insulation qualities.

When insulating the floor of the first floor with polystyrene foam, the material is sometimes left exposed. The fact is that mice often gnaw on polystyrene foam, taking its crumbs and “insulating” their holes with it. This approach helps to preserve the vapor barrier layer and, if necessary, update the heat insulation sheets without any problems.

It happens that a builder saves on tape and leaves the overlap of plastic film unsecured. The moisture contained in the air penetrates through the edges of the film into the mineral wool and it becomes damp. That's why It is important to ensure that workers comply with the work technology.

Examples of successful designs

Consider the following:

• A classic “pie” with insulation from above using a screed under the finished floor.

• Installation of logs “staggered”, filling with expanded clay on top of the film, covering with plywood.

• High-quality filling of gaps between joists and sheets with construction foam.
• Laying slabs in the space between the beams on top of a layer of isospan.

• Application wide boards, mounted on edge.
• Double-sided waterproofing with mineral wool.