In order to enjoy the warmth and comfort in your home in winter, you need to take care of its thermal insulation in advance. Today, this is completely easy to do, because the construction market has a wide range of heaters. Each of them has its own pluses and minuses, it is suitable for insulation under certain operating conditions. When choosing a material, such a criterion as thermal conductivity remains very important.

What is thermal conductivity

It is the process of releasing thermal energy in order to obtain thermal equilibrium. The temperature regime must be leveled, the main thing is the speed with which this task will be carried out. If we consider the thermal conductivity in relation to the house, then the longer the process of equalizing the air temperatures in the house and on the street takes place, the better. In simple terms, thermal conductivity is an indicator by which you can understand how quickly the walls in a house cool down.

This criterion is presented in numerical value and is characterized by the coefficient of thermal conductivity. Thanks to him, you can find out how much heat energy per unit of time can pass through a unit of surface. The higher the thermal conductivity of the insulation, the faster it conducts thermal energy.

The video shows the types of heaters and their characteristics:

The lower the value of the heat conductivity coefficient, the longer the material will be able to retain heat in winter days and cool in summer. But there are a number of other factors that must also be taken into account when choosing an insulating material.

Expanded polystyrene

This heat insulator is one of the most demanded. And this is due to its low heat conductivity, low cost and ease of installation. On store shelves, the material is presented in slabs, 20-150 mm. Obtained by foaming polystyrene. The resulting cells are filled with air. Foam is characterized by different densities, low heat conductivity and moisture resistance.

In the photo - expanded polystyrene

Since expanded polystyrene is inexpensive, it is widely popular among many developers for insulating various houses and buildings. But foam has its drawbacks. It is very fragile and flammable quickly and releases harmful toxins into the environment when burned. For this reason, it is better to use polystyrene for insulating non-residential buildings and unloaded structures. For residential premises, you should pay attention to foil.

And in this article you can see the table of thermal conductivity of expanded clay concrete blocks. For this it is worth going

Extruded polystyrene foam

This material is not afraid of the influence of moisture and decay. It is durable and easy to install. Easy to machine. It has a low level of water absorption, therefore, at high humidity, extruded polystyrene foam retains its properties. Insulation refers to fireproof materials, it has a long service life and ease of installation.

In the photo - extruded polystyrene foam

The presented characteristics and low heat conductivity will make it possible to call extruded polystyrene foam the best insulation for strip foundations and blind areas. When installing a sheet with a thickness of 50 mm, you can replace a foam block with a thickness of 60 mm in terms of heat conductivity. At the same time, the insulation does not allow water to pass through, so there is no need to worry about auxiliary waterproofing.

Mineral wool

Minvata is a heater that can be classified as natural and environmentally friendly. Mineral wool has a low coefficient of heat conductivity and is completely unaffected by fire. Insulation is produced in the form of plates and rolls, each of which has its own stiffness indicators. In the article you can read about what is good about mineral or.

In the photo - mineral wool

If you need to isolate the horizontal surface, then it is worth using dense mats, and for vertical ones - rigid and semi-rigid plates. As for the disadvantages, it has a low resistance to moisture, so when installing it, you need to take care of moisture and vapor barrier. It is not worth using mineral wool for arranging a basement, cellar, steam room in a bath. Although if you correctly lay out the waterproofing layer, then the mineral wool will serve for a long time and efficiently. But what is the thermal conductivity of mineral wool, information from

Basalt wool

This insulation is obtained by melting basalt rocks with the addition of auxiliary components. The result is a material with a fibrous structure and excellent water repellency. The insulation is non-flammable and completely safe for health. In addition, basalt has excellent performance for high-quality sound and heat insulation. It can be used for insulation both outside and inside the house.

In the photo - basalt wool for insulation

When installing basalt wool, you must wear protective equipment. This includes gloves, a respirator, and goggles. This will protect the mucous membranes from the ingress of cotton wool debris. When choosing basalt wool, the Rockwool brand is very popular today. The article can be found about.

During the operation of the material, you do not have to worry that the plates will be compacted or caked. And this speaks of the excellent properties of low thermal conductivity, which do not change over time.

Penofol

This insulation is produced in the form of rolls, the thickness of which is 2-10 mm. The material is based on foamed polyethylene. On sale you can find a heat insulator, on one side of which there is a foil to form a reflective background. The thickness of the material is several times less than the previously presented materials, but at the same time it does not affect the thermal conductivity at all. It is able to reflect up to 97% of heat. Foamed polyethylene boasts a long service life and environmental friendliness.

In the photo, Penofol insulation:

Izolon is completely light, thin and easy to install. A roll-up heat insulator is used when arranging wet rooms, which include a basement, a balcony. In addition, the use of insulation will allow you to save the useful area of ​​the room if you install it inside the house.

But what is the thermal conductivity of ceramic bricks and where such a building material is used, the information will help to understand

What is the thermal conductivity of the substrate under the laminate and how to make the correct calculations, is described in this

Table 1 - Indicators of heat conductivity of popular materials

Thermal conductivity is one of the main criteria when choosing a thermal insulation material. If you install a heater with a low coefficient of thermal conductivity, it will allow you to keep the heat in the house for a longer time, thus creating the most comfortable living conditions.

The ability of bodies and substances to transfer internal energy, defined in macro-processes by the term "thermal energy" is called thermal conductivity. In engineering and construction, the thermal conductivity of external structures is one of the most important standardized criteria.

The thermal conductivity formula (Fourier's law), which is discussed below in more detail, relates the amount of heat energy transferred per unit time through a unit area through the thermal conductivity coefficient, which serves as the basic characteristic of building structures in terms of their heat transfer.

The thermal conductivity of some thermal insulation materials makes them unsuitable for use in building a house, although their other indicators are quite acceptable. The thermal conductivity of mixtures and composite materials used for the construction of houses is usually higher than that of other substances, since this property is taken into account when developing their compositions.

It is possible to numerically determine the coefficient of thermal conductivity of a material using special devices and techniques that are required to comply with the existing architectural standards in Russia.

Building insulation materials and their thermal conductivity

The thermal conductivity of a structure is not only a function of the components that make up it, the porosity of the insulation plays an important role, since air is a good heat insulator. The heat transfer of porous materials is significantly lower than that of monolithic materials.

Comparison of the spectrum of properties of structural products, which includes: strength characteristics, permissible loads, thermal conductivity of materials and the required thicknesses to comply with thermal conductivity standards, leads to the conclusion that the construction of a high-quality modern house requires the use of heat-insulating materials with high insulating capacity per unit volume and weight.

A separate direction in the creation of heat-insulating materials is the insulation of pipelines. Pipes significantly affect the useful volume of living space, therefore, a significant reduction in the thickness of their thermal insulation, required for the normal functioning of the system, is one of the important requirements of modern design.

Environmental properties and heat transfer

Heat transfer in building structures depends not only on the properties of thermal insulation materials and temperature differences, but also on environmental parameters. The lower the dew point, that is, the less water in the air, the lower its thermal conductivity. In this case, cold air always has a lower dew point.

Therefore, in order to improve the thermal insulation of the living space, vapor barrier materials are used, the action of which is based on the principle of membranes. They separate humid air on one side of the thermal insulation materials, from the air at their surface, in order to significantly reduce the thermal conductivity of the wall.

Comparison of the thicknesses of heat-insulating materials required to ensure the permissible architectural norms of a house being built with and without vapor barrier leads to an unambiguous conclusion about the unequivocal need to use the proposed membrane fabrics together with heat-insulating fabrics in the wall and roof heat-insulating layers.

Thermal insulation materials used for arranging pipes for heating systems and water supply systems are mainly products made of porous materials with low thermal conductivity, having continuous films on their surfaces obtained by extrusion, which in turn ensures a constant dew point inside the pores. Therefore, the diameter of products for reliable pipe insulation is much smaller than would be required without the presence of such surfaces.

Thermal conductivity table

The thermal conductivity of some materials is shown in the table below. Information on other building construction products can be found in the reference book.

Expanded polystyrene

Foamed insulation based on styrene and styrene-butadiene compositions. Possesses good thermal insulation properties, it is used for insulation of walls and pipes.

Extrusion boards

Various in basis (mainly - polyurethane foam and expanded polystyrene). Plates have docking grooves, which does not require sealing them together. These are modern materials used to insulate any large and flat surfaces.

Penofol

Foamed polyethylene foam. It has a number of advantages: it is elastic, does not allow air to pass through, and has a reflective surface. It is used for thermal insulation of walls, pipes, floors, has good heat-insulating properties, but it does not "breathe", in other words, moisture can condense on its surface with a large temperature difference.

Mineral wool

Mineral fiber insulation. It is widely used for insulating walls, floors and roofs, it is indispensable for insulating complex non-planar surfaces. It can be used as a winding for large diameter pipes. More elastic than basalt wool, it has less weight. For the rest of the characteristics, it is slightly worse, with the exception of the price.

Basalt wool

One of the most modern premium elastic sheet insulation. Slightly less elastic than mineral wool. It has a higher specific weight, large transport dimensions, and a higher cost.

Styrofoam

Foamed polyurethane foam. It is used in the form of "butt-joint" slabs. It is used for insulation of walls, floors and ceilings, roofing.

Loose and organic materials

Loose and organic materials (expanded clay, slag, sawdust, shavings) are used for filling cavities, hollow walls, ceilings). They have a number of disadvantages: hygroscopicity, compaction over time, low vapor barrier ability. The main advantages are availability and cost.

Comparison of vapor permeability of heaters

Name of material Thermal conductivity, W / m * K Vapor permeability, mg / m * h * Pa Moisture absorption,%

Flammability group

Minvata 0.037-0.048 0.49-0.6 1.5 NG
Polyfoam 0.036-0.041 0.03 3 G1-G4
PPU 0.023-0.035 0.02 2 G2
Penoizol 0.028-0.034 0.21-0.24 18 G1
Ecowool 0.032-0.041 0.3 1 G2

The thermal conductivity potential of the walls of the house, equal to the sum of the thermal conductivities of all layers of their structure, divided by their thickness, shows how much this structure can retain heat.

Comparative analysis of the data from the table of thermal conductivity of materials and heaters makes it possible to carry out calculations about their applicability in certain cases. The thermal conductivity of building materials at home, as mentioned above, also depends on the dew point of the environment between its surfaces.

Fourier's law of thermal conductivity

In conclusion, a few words about the theoretical basis of the phenomenon of heat transfer and thermal conductivity. To calculate the coefficient of thermal conductivity of materials, Fourier's law is used, which describes the relationship between the rate of passage of thermal energy through a unit section.

Thermal conductivity through the coefficient λ is related to the physical parameters of the body. If a parallelepiped is considered as a heat-conducting body, then the amount of heat passing through it per unit time can be described by the following formula (Fourier's law):

P = λ × S∆T / l, where P is the power of heat losses, S is the cross-sectional area of ​​the parallelepiped, T is the temperature difference between the edges, l is the length of the parallelepiped (the distance between the edges).
In other words, the coefficient determined by measuring the temperature difference is equal to the amount of heat that passes through a square centimeter of the material's cross-section per unit of time.

Today we will be doing a comparative analysis of various thermal insulation materials. Let's compare heaters for strength, thermal conductivity, flammability, etc. Let's compare the prices for the material and the costs of its installation. We will try to present the information in such a way that it would be most simple and comfortable for you to choose the best option for yourself. Of course, comparing heaters designed for completely different purposes is completely useless. Therefore, we will break down our comparison according to the application: thermal insulation of the foundation, thermal insulation of walls, roofs, etc.

1. Comparison of heaters for unloaded structures: attic, pitched roof, frame walls, floor between logs

Summary table of characteristics of low-density insulators used in unloaded structures:

The most important characteristic of a heater is thermal conductivity, i.e. its ability to transmit heat. The lower the thermal conductivity, the better the insulation. The thermal conductivity index is indicated for our climatic zone (middle zone of Russia). As we can see from the table, mineral wool P-75 (P-60 or P-80) will be the worst to insulate. Thus, this insulation will need to be laid one and a half times more than, for example, Penoplex, whose thermal conductivity indicators are the best.

The density of the material for mineral insulation will affect their ability to withstand loads (in our case, its own weight), which means the possibility of using it in vertical structures (walls). It is recommended to use mineral insulation with a density of at least 40 kg / m³ in the walls, otherwise they can shrink, forming cold bridges. Insulation materials are suitable for walls:,.

This rule does not apply to expanded polystyrene (including extruded), which has sufficient strength at a low density to be used in vertical structures. But these materials, unlike mineral ones, are flammable and not breathable. And the foam, and moreover, emits harmful substances, sometimes with a noticeable odor.

And, of course, its price is important in choosing a heater. It is difficult to estimate the real cost of the material in a store, because the price is indicated for a package, and their volume is always different. Therefore, in our comparison, we used the price per cubic meter. Note that prices may change over time, but their relationship to each other remains approximately the same. So, the most expensive material from those presented by a wide margin is extruded polystyrene foam, in second place is a basalt mineral wool insulation. The cheapest material is polystyrene, but with a very small margin, it is followed by basalt insulation.

Minvata P-75 is made from metallurgical slags, it is unpleasant to the touch and can crumble, forming a suspension that can have a negative effect on human health. Therefore, it should only be mounted in protective clothing and a mask. Needless to say, it is not advisable to have such insulation in a residential building if you want to be healthy. Almost the same will cost, which, although it has a slightly lower density, is much better quality. An even more interesting option for a price of about 1,500 rubles per cubic meter is, with the proviso that its density is even lower, which means that it is recommended to use it only in horizontal and inclined unloaded structures.

Output: for vertical frame walls, the best choice would be , and for inclined and horizontal structures (pitched roof, floors), the best choice would be .

2. Comparison of heaters for external walls for plastering

3. Comparison of heaters for combustibility

We bring to your attention a video with tests of common heaters for flammability.

Foreword... In the modern market, there is simply a huge selection of materials that differ in price and other characteristics. Let's try to compare the thermal conductivity of heaters and understand this variety in order to make an informed decision in favor of a certain heater. Consider which parameters are more important when choosing - thermal conductivity or other characteristics.

The main characteristics of heaters

We will provide, for starters, the characteristics of the most popular thermal insulation materials, which are the first to pay attention to when choosing. Comparison of heaters in terms of thermal conductivity should be made only on the basis of the purpose of materials and conditions in the room (humidity, the presence of an open fire, etc.). We have arranged further in order of importance the main characteristics of heaters.

Thermal conductivity... The lower this indicator, the less a layer of thermal insulation is required, which means that the cost of insulation will also be reduced.

Moisture permeability... The lower permeability of the material to moisture vapor reduces the negative impact on the insulation during operation.

Fire safety... Thermal insulation should not burn and emit poisonous gases, especially when insulating a boiler room or chimney.

Durability... The longer the service life, the cheaper it will cost you during operation, since it does not require frequent replacement.

Environmental friendliness... The material must be safe for humans and the environment.

Profitability... The material should be available to a wide range of consumers and have an optimal price / quality ratio.

Ease of installation... This property for a heat-insulating material is very important for those who wish to make repairs on their own.

Material thickness and weight... The thinner and lighter the insulation, the less the structure will become heavier when installing thermal insulation.

Soundproofing... The higher the sound insulation value of the material, the better the protection in the living space from extraneous noise from the street will be.

Expanded polystyrene (styrofoam)

It is the most popular thermal insulation material in Russia due to its low thermal conductivity, low cost and ease of installation. Polyfoam is made in plates with a thickness of 20 to 150 mm by foaming polystyrene and consists of 99% of air. The material has various densities, low thermal conductivity and moisture resistance.

Due to its low cost, expanded polystyrene is in great demand among companies and private developers for insulating various premises. But the material is quite fragile and quickly ignites, releasing toxic substances during combustion. Because of this, it is preferable to use polystyrene in non-residential premises and for thermal insulation of unloaded structures - insulation of the facade under plaster, basement walls, etc.

Extruded polystyrene foam

Extrusion (technoplex, penoplex, etc.) is not affected by moisture and decay. It is a very durable and easy-to-use material that can be easily cut with a knife to the required size. Low water absorption provides a minimum change in properties at high humidity, the boards have high density and resistance to compression. Extruded polystyrene foam is fireproof, durable and easy to use.

All these characteristics, along with low thermal conductivity in comparison with other heaters, make Technoplex, URSA XPS or Penoplex slabs an ideal material for insulating strip foundations of houses and blind areas. According to the assurances of the manufacturers, an extrusion sheet 50 millimeters thick replaces a 60 mm foam block in terms of thermal conductivity, while the material does not allow moisture to pass through and additional waterproofing can be dispensed with.

Mineral wool

Isover mineral wool slabs in the package

Minvata (for example, Isover, URSA, Technoruf, etc.) is made from natural materials - slag, rocks and dolomite using a special technology. Mineral wool has low thermal conductivity and is absolutely fireproof. The material is produced in slabs and rolls of various hardness. For horizontal planes, less dense mats are used; for vertical structures, rigid and semi-rigid slabs are used.

However, one of the significant disadvantages of this insulation, like basalt wool, is its low moisture resistance, which requires additional moisture and vapor barrier when installing the mineral wool. Experts do not recommend using mineral wool for insulating wet rooms - basements of houses and cellars, for thermal insulation of the steam room from the inside in saunas and dressing rooms. But even here it can be used with proper waterproofing.

Basalt wool

This material is produced by melting basalt rocks and blowing the molten mass with the addition of various components to obtain a fibrous structure with water-repellent properties. The material is non-flammable, safe for human health, has good performance in thermal insulation and sound insulation of premises. It is used for both internal and external thermal insulation.

When installing basalt cotton wool, protective equipment (gloves, respirator and goggles) should be used to protect mucous membranes from cotton wool microparticles. The most famous brand of basalt wool in Russia is materials under the Rockwool brand. During operation, the thermal insulation slabs are not compacted or caked, which means that the excellent properties of low thermal conductivity of basalt wool remain unchanged over time.

Penofol, izolon (foamed polyethylene)

Penofol and Izolon are roll insulation with a thickness of 2 to 10 mm, consisting of foamed polyethylene. The material is also available with a layer of foil on one side to create a reflective effect. The insulation has a thickness several times thinner than the previously presented insulation, but at the same time retains and reflects up to 97% of thermal energy. Foamed polyethylene has a long service life and is environmentally friendly.

Izolon and foil-clad penofol are light, thin and very easy-to-use heat-insulating material. Roll insulation is used to insulate damp rooms, for example, when insulating balconies and loggias in apartments. Also, the use of this insulation will help you save usable space in the room, while insulating it inside. Read more about these materials in the section "Organic thermal insulation".

Comparison of heaters. Thermal conductivity table

Last time we defined ... Today we will compare heaters. You can find a table with general characteristics in the summary of the article. We have selected the most popular materials, including mineral wool, polyurethane foam, penoizol, polystyrene and ecowool. As you can see, these are versatile insulation materials with a wide range of applications.

Comparison of thermal conductivity of heaters

The higher the thermal conductivity, the worse the material works as insulation.

We start comparing thermal insulation materials for a reason, since this is undoubtedly the most important characteristic. It shows how much heat the material passes not over a certain period of time, but constantly. Thermal conductivity is expressed as a coefficient and is calculated in watts per square meter. For example, a coefficient of 0.05 W / m * K indicates that constant heat loss per square meter is 0.05 watts. The higher the coefficient, the better the material conducts heat, respectively, as a heater it works worse.

Below is a table comparing popular thermal insulation materials:

Having studied the above types of insulation and their characteristics, we can conclude that, with equal thickness, the most effective thermal insulation among all is liquid two-component polyurethane foam (PPU).

The thickness of the insulation is of paramount importance, it must be calculated for each case individually. The result is influenced by the region, the material and thickness of the walls, the presence of air buffer zones.

Comparative characteristics of heaters show that thermal conductivity is affected by the density of the material, especially for mineral wool. The higher the density, the less air in the structure of the insulation. As you know, air has a low coefficient of thermal conductivity, which is less than 0.022 W / m * K. Based on this, with an increase in density, the coefficient of thermal conductivity also increases, which negatively affects the ability of the material to retain heat.

Comparison of vapor permeability of heaters

High vapor permeability = no condensation.

Vapor permeability is the ability of a material to pass air, and with it steam. That is, the insulation can breathe. Manufacturers have been focusing a lot of attention on this characteristic of home insulation lately. In fact, high vapor permeability is needed only when ... In all other cases, this criterion is not categorically important.

Characteristics of heaters for vapor permeability, table:

Comparison of heaters for walls showed that natural materials have the highest degree of vapor permeability, while polymer heaters have an extremely low coefficient. This indicates that materials such as polyurethane foam and polystyrene have the ability to retain steam, that is, they perform ... Penoizol is also a kind of polymer made from resins. Its difference from polyurethane foam and polystyrene lies in the structure of the cells that open. In other words, it is a material with an open-cell structure. The ability of thermal insulation to pass steam is closely related to the next characteristic - moisture absorption.

Thermal insulation hygroscopicity overview

High hygroscopicity is a drawback that needs to be eliminated.

Hygroscopicity - the ability of a material to absorb moisture, measured as a percentage of its own weight of insulation. Hygroscopicity can be called the weak side of thermal insulation and the higher this value, the more serious measures will be required to neutralize it. The fact is that water, getting into the structure of the material, reduces the effectiveness of the insulation. Comparison of the hygroscopicity of the most common thermal insulation materials in civil construction:

Comparison of the hygroscopicity of heaters for the house showed high moisture absorption of penoizol, while this thermal insulation has the ability to distribute and remove moisture. Due to this, even when wet by 30%, the thermal conductivity does not decrease. Despite the fact that mineral wool has a low percentage of moisture absorption, it especially needs protection. After drinking water, she holds it, not allowing it to go outside. At the same time, the ability to prevent heat loss is dramatically reduced.

To exclude the ingress of moisture into the mineral wool, vapor barrier films and diffusion membranes are used. Basically, polymers are resistant to prolonged exposure to moisture, with the exception of ordinary polystyrene foam, it quickly degrades. In any case, water did not benefit any thermal insulation material, therefore it is extremely important to exclude or minimize their contact.

Installation and operational efficiency

Installation of PPU is quick and easy.

Comparison of the characteristics of heaters should be carried out taking into account the installation, because this is also important. It is easiest to work with liquid thermal insulation, such as polyurethane foam and penoizol, but this requires special equipment. It is also easy to lay ecowool (cellulose) on horizontal surfaces, for example, when or attic floor. For spraying ecowool on walls with the wet method, special devices are also needed.

Polyfoam is laid both along the crate and directly onto the work surface. In principle, this also applies to stone wool slabs. Moreover, it is possible to lay slab insulation on both vertical and horizontal surfaces (including under the screed). Soft glass wool in rolls is laid only along the crate.

During operation, the thermal insulation layer may undergo some undesirable changes:

• saturate moisture;
• shrink;
• become a home for mice;
• collapse from exposure to infrared rays, water, solvents, etc.

In addition to all of the above, the fire safety of thermal insulation is of great importance. Comparison of heaters, table of flammability group:

Outcomes

Today we reviewed the most commonly used home insulation materials. Based on the results of comparing different characteristics, we obtained data on thermal conductivity, vapor permeability, hygroscopicity and the degree of flammability of each of the heaters. All this data can be combined into one common table:

In addition to these characteristics, we have determined that it is easiest to work with liquid insulation and eco-wool. PPU, penoizol and ecowool (wet installation) are simply sprayed onto the work surface. Dry ecowool is filled up manually.