Characteristics of building materials for thermal conductivity. How thick should the insulation be, comparison of the thermal conductivity of materials. Factors affecting thermal conductivity

The process of transferring energy from a hotter part of the body to a less heated one is called thermal conduction. The numerical value of such a process reflects the thermal conductivity of the material. This concept is very important in the construction and repair of buildings. Properly selected materials allow you to create a favorable microclimate in the room and save a significant amount on heating.

The concept of thermal conductivity

Thermal conductivity is the process of thermal energy exchange, which occurs due to the collision of the smallest particles of the body. Moreover, this process will not stop until the moment of temperature equilibrium comes. This takes a certain amount of time. The more time spent on heat exchange, the lower the thermal conductivity.

This indicator is expressed as the coefficient of thermal conductivity of materials. The table contains already measured values ​​for most materials. The calculation is made according to the amount of thermal energy that has passed through a given surface area of ​​the material. The larger the calculated value, the faster the object will give up all its heat.

Factors affecting thermal conductivity

The thermal conductivity of a material depends on several factors:

• With an increase in this indicator, the interaction of material particles becomes stronger. Accordingly, they will transfer the temperature faster. This means that with an increase in the density of the material, heat transfer improves.

• The porosity of a substance. Porous materials are heterogeneous in their structure. There is a lot of air inside them. And this means that it will be difficult for molecules and other particles to move thermal energy. Accordingly, the coefficient of thermal conductivity increases.

• Humidity also has an effect on thermal conductivity. Wet material surfaces allow more heat to pass through. Some tables even indicate the calculated thermal conductivity of the material in three states: dry, medium (normal) and wet.

When choosing a material for room insulation, it is also important to consider the conditions in which it will be used.

The concept of thermal conductivity in practice

Thermal conductivity is taken into account at the design stage of a building. This takes into account the ability of materials to retain heat. Thanks to their correct selection, residents inside the premises will always be comfortable. During operation, money for heating will be significantly saved.

Insulation at the design stage is optimal, but not the only solution. It is not difficult to insulate an already finished building by carrying out internal or external work. The thickness of the insulation layer will depend on the materials chosen. Some of them (for example, wood, foam concrete) can in some cases be used without an additional layer of thermal insulation. The main thing is that their thickness exceeds 50 centimeters.

Particular attention should be paid to the insulation of the roof, window and doorways, gender. Most of the heat escapes through these elements. Visually, this can be seen in the photo at the beginning of the article.

Structural materials and their indicators

For the construction of buildings, materials with a low coefficient of thermal conductivity are used. The most popular are:

• Reinforced concrete, the thermal conductivity value of which is 1.68 W / m * K. The density of the material reaches 2400-2500 kg/m 3 .

• Wood has been used as a building material since ancient times. Its density and thermal conductivity, depending on the rock, are 150-2100 kg / m 3 and 0.2-0.23 W / m * K, respectively.

Another popular building material is brick. Depending on the composition, it has the following indicators:

• adobe (made from clay): 0.1-0.4 W / m * K;

• ceramic (made by firing): 0.35-0.81 W / m * K;

• silicate (from sand with the addition of lime): 0.82-0.88 W / m * K.

Concrete materials with the addition of porous aggregates

The thermal conductivity of the material allows you to use the latter for the construction of garages, sheds, summer houses, baths and other structures. This group includes:

• Expanded clay concrete, the performance of which depends on its type. Solid blocks do not have voids and holes. With voids inside, they are made which are less durable than the first option. In the second case, the thermal conductivity will be lower. If we consider the general figures, then it is 500-1800kg / m3. Its indicator is in the range of 0.14-0.65 W / m * K.

• Aerated concrete, inside which pores 1-3 mm in size are formed. This structure determines the density of the material (300-800kg/m3). Due to this, the coefficient reaches 0.1-0.3 W / m * K.

Indicators of thermal insulation materials

Coefficient of thermal conductivity thermal insulation materials, the most popular in our time:

• expanded polystyrene, the density of which is the same as that of the previous material. But at the same time, the heat transfer coefficient is at the level of 0.029-0.036 W / m * K;

• glass wool. It is characterized by a coefficient equal to 0.038-0.045 W / m * K;

• with an indicator of 0.035-0.042 W / m * K.

Table of indicators

For convenience, the coefficient of thermal conductivity of the material is usually entered in the table. In addition to the coefficient itself, such indicators as the degree of humidity, density, and others can be reflected in it. Materials with a high coefficient of thermal conductivity are combined in the table with indicators of low thermal conductivity. An example of this table is shown below:

Using the coefficient of thermal conductivity of the material will allow you to build the desired building. The main thing: to choose a product that meets all the necessary requirements. Then the building will be comfortable for living; it will maintain a favorable microclimate.

Properly selected will reduce due to which it will no longer be necessary to “heat the street”. Thanks to this, financial costs for heating will be significantly reduced. Such savings will soon return all the money that will be spent on the purchase of a heat insulator.

Construction of a cottage or country house is a complex and laborious process. And in order for the future building to stand for more than a dozen years, it is necessary to comply with all norms and standards during its construction. Therefore, each stage of construction requires accurate calculations and high-quality performance of the necessary work.

One of the most important indicators during the construction and decoration of the building is the thermal conductivity building materials. SNIP ( building codes and rules) provides a full range of information on this issue. You need to know it so that the future building is comfortable for living both in summer and in winter.

Perfect warm home

From design features the structure and the materials used in its construction depends on the comfort and economy of living in it. Comfort consists in creating an optimal microclimate inside, regardless of external weather conditions and temperature. environment. If the materials are chosen correctly, and the boiler equipment and ventilation are installed in accordance with the norms, then in such a house there will be a comfortable cool temperature in summer and warm in winter. In addition, if all materials used in construction have good thermal insulation properties, then the energy costs for space heating will be minimal.

The concept of thermal conductivity

Thermal conductivity is the transfer of thermal energy between directly contacting bodies or media. In simple words thermal conductivity is the ability of a material to conduct temperature. That is, getting into some medium with a different temperature, the material begins to take on the temperature of this medium.

This process has great importance and in construction. So, in the house with the help heating equipment the optimum temperature is maintained (20-25°C). If the temperature outside is lower, then when the heating is turned off, all the heat from the house will go outside after a while, and the temperature will drop. In summer, the situation is reversed. To make the temperature in the house below the street, you have to use air conditioning.

Coefficient of thermal conductivity

Heat loss in the house is inevitable. It happens all the time when the outside temperature is lower than the room temperature. But its intensity is a variable. It depends on many factors, the main ones being:

• The area of ​​surfaces involved in heat exchange (roof, walls, ceilings, floor).
• Thermal conductivity index of building materials and individual building elements (windows, doors).
• The difference between the temperatures outside and inside the house.
• And others.

To quantify the thermal conductivity of building materials, a special coefficient is used. Using this indicator, you can quite simply calculate the necessary thermal insulation for all parts of the house (walls, roof, ceilings, floor). The higher the thermal conductivity of building materials, the greater the intensity of heat loss. Thus, to build warm home it is better to use materials with a lower indicator of this value.

The thermal conductivity coefficient of building materials, like any other substances (liquid, solid or gaseous), is denoted by the Greek letter λ. Its unit is W/(m*°C). In this case, the calculation is carried out on one square meter walls one meter thick. The temperature difference here is taken as 1°. In almost any building guide there is a table of thermal conductivity of building materials, in which you can see the value of this coefficient for various blocks, bricks, concrete mixtures, wood species and other materials.

Determination of heat loss

There are always heat losses in any building, but depending on the material, they can change their value. On average, heat loss occurs through:

• Roof (from 15% to 25%).
• Walls (from 15% to 35%).
• Windows (from 5% to 15%).
• Door (from 5% to 20%).
• Gender (from 10% to 20%).

To determine heat loss, a special thermal imager is used, which determines the most problematic areas. They are highlighted in red. Less heat loss occurs in the yellow zones, then in the green ones. Areas with the least heat loss are highlighted in blue. And the determination of the thermal conductivity of building materials should be carried out in special laboratories, as evidenced by the quality certificate attached to the product.

Example of heat loss calculation

If we take, for example, a wall made of a material with a thermal conductivity coefficient of 1, then with a temperature difference of 1 ° on both sides of this wall, the heat loss will be 1 W. If the wall thickness is taken not 1 meter, but 10 cm, then the losses will be already 10 watts. If the temperature difference is 10°, then the heat loss will also be 10 W.

Let us now consider, using a specific example, the calculation of the heat loss of an entire building. We take its height 6 meters (8 with a skate), width - 10 meters, and length - 15 meters. For simplicity of calculations, we take 10 windows with an area of ​​​​1 m 2. The indoor temperature will be considered equal to 25°C, and outside -15°C. Calculate the area of ​​all surfaces through which heat loss occurs:

• Windows - 10 m 2.
• Floor - 150 m2.
• Walls - 300 m 2.
• Roof (with slopes on the long side) - 160 m 2.

The formula for the thermal conductivity of building materials allows you to calculate the coefficients for all parts of the building. But it is easier to use ready-made data from the directory. There is a table of thermal conductivity of building materials. Consider each element separately and determine its thermal resistance. It is calculated by the formula R = d/λ, where d is the thickness of the material, and λ is its thermal conductivity.

Floor - 10 cm concrete (R=0.058 (m 2 *°C)/W) and 10 cm mineral wool (R=2.8 (m 2 *°C)/W). Now add these two numbers. Thus, the thermal resistance of the floor is 2.858 (m 2 * °C) / W.

Similarly, walls, windows and roofs are considered. Material - cellular concrete (aerated concrete), thickness 30 cm. In this case, R = 3.75 (m 2 * ° C) / W. Thermal resistance of the formation window - 0.4 (m 2 *°C)/W.

The following formula allows you to find out the loss of thermal energy.

Q = S * T / R, where S is the surface area, T is the temperature difference between outside and inside (40°C). Calculate the heat loss for each element:

• For the roof: Q \u003d 160 * 40 / 2.8 \u003d 2.3 kW.
• For walls: Q \u003d 300 * 40 / 3.75 \u003d 3.2 kW.
• For windows: Q \u003d 10 * 40 / 0.4 \u003d 1 kW.
• For the floor: Q \u003d 150 * 40 / 2.858 \u003d 2.1 kW.

Further, all these indicators are summarized. Thus, for this cottage, the heat loss will be 8.6 kW. And to maintain the optimum temperature, boiler equipment with a capacity of at least 10 kW is required.

Materials for external walls

Today, there are many wall building materials. But the most popular in private housing construction are still building blocks, bricks and wood. The main differences are the density and thermal conductivity of building materials. Comparison makes it possible to choose the golden mean in the density / thermal conductivity ratio. The higher the density of the material, the higher its bearing capacity, and hence the strength of the structure as a whole. But at the same time, its thermal resistance is lower, and as a result, energy costs are higher. On the other hand, the higher the thermal resistance, the lower the density of the material. Lower density generally implies a porous structure.

To weigh the pros and cons, you need to know the density of the material and its coefficient of thermal conductivity. The following table of thermal conductivity of building materials for walls gives the value of this coefficient and its density.

Wall insulation

With insufficient thermal resistance of external walls, various heaters can be used. Since the thermal conductivity values ​​​​of building materials for insulation can have a very low indicator, most often a thickness of 5-10 cm will be enough to create a comfortable temperature and microclimate in the premises. Materials such as mineral wool, expanded polystyrene, foam plastic, polyurethane foam and foam glass.

The following table of thermal conductivity of building materials used for thermal insulation of external walls gives the value of the coefficient λ.

Features of the use of wall insulation

The use of insulation for external walls has some limitations. This is primarily due to such a parameter as vapor permeability. If the wall is made of a porous material, such as aerated concrete, foam concrete or expanded clay concrete, then it is better to use mineral wool, since this parameter is almost the same for them. The use of expanded polystyrene, polyurethane foam or foam glass is possible only if there is a special ventilation gap between the wall and the insulation. For a tree, this is also critical. But for brick walls, this parameter is not so critical.

Warm roof

Roof insulation helps to avoid unnecessary cost overruns when heating a house. For this, all types of heaters, both sheet format and sprayed (polyurethane foam), can be used. In this case, one should not forget about vapor barrier and waterproofing. This is very important, since wet insulation (mineral wool) loses its thermal resistance properties. If the roof is not insulated, then it is necessary to thoroughly insulate the ceiling between the attic and the top floor.

Floor

Floor insulation is very milestone. In this case, it is also necessary to apply vapor barrier and waterproofing. As a heater, a denser material is used. It, accordingly, has a higher coefficient of thermal conductivity than roofing. An additional measure for floor insulation can be a basement. Availability air gap allows you to increase the thermal protection of the house. And the equipment of the underfloor heating system (water or electric) provides an additional source of heat.

Conclusion

During the construction and finishing of the facade, it is necessary to be guided by accurate calculations of heat losses and take into account the parameters of the materials used (thermal conductivity, vapor permeability and density).

The thermal conductivity of building materials (a table of its values ​​\u200b\u200bwill be given in the article below) is a very important criterion that you absolutely need to pay attention to during this stage of organization construction works like: purchase of raw materials.

This indicator should be taken into account not only when building an object from scratch, but also when repair work, including the installation of walls (both external and internal).

Basically, the future level of comfort indoors depends on the thermal conductivity of the selected materials. However, this criterion also affects some technical indicators, which can be found in more detail in this article.

Thermal conductivity - definition

Before determining the thermal conductivity of a particular material, it is important to know in advance: what is this term in general.

As a rule, under the definition of "thermal conductivity", it is customary to understand the level of heat transfer of a certain material, expressed in watts / meter kelvin.

More plain language, this coefficient shows the ability of the material to receive energy from more heated bodies, and the level of return of its energy to bodies with a lower temperature. As a rule, this indicator is calculated according to one of two main formulas: q = x*grad(T) or P=-x*.

What affects thermal conductivity

The thermal conductivity coefficient of each building material is determined strictly individually, what should be paid attention to Special attention, and it depends on several main criteria:

• density;
• porosity level;
• structure and shape of pores;
• natural temperature;
• humidity level;
• chemical structure (atomic group).

For example, if there is a material structure a large number small pores, closed type, its level of thermal conductivity will decrease significantly. However, in the variant with large pores, this coefficient will, on the contrary, be increased due to the occurrence of convective air flows in the pores.

Table

As mentioned earlier: each building material has an individual thermal conductivity coefficient, which is calculated based on some characteristic criteria.

For a clearer picture, we give in the table examples of the thermal conductivity of some of the most common materials used in construction:

Varieties of insulation structures

Vermiculite

The selection of material for insulation of any structure is primarily carried out based on its type: external or internal. In the first variant, substances that are not susceptible to weather conditions and other external factors are well suited as a heater, namely:

• expanded clay;
• perlite gravel.

For greater effect, the insulation can be applied in two layers, where the above materials will be considered a protective layer, and as a base, they can well act:

• Styrofoam;
• penoizol;
• expanded polystyrene;
• polyurethane foam.

Penoizol

As regards exclusively internal version insulation of structures, then the following materials are quite suitable for this:

• mineral wool;
• glass wool;
• cotton wool from basalt fiber;

In addition to the scope of application, heaters differ significantly in their cost, thermal conductivity, tightness, as well as service life, which should be paid attention to when choosing them.

When choosing a heater, first of all, it is important to pay attention to the scope of its application. For example, when choosing insulation material for exterior finish object, make sure that its density is high enough, and its structure has reliable protection from temperature changes, moisture ingress, physical impact, etc.

Also, try to select such materials, the weight of which will not be very large, so as not to destroy the foundation of the building. After all, it is not uncommon that the insulation has to be mounted on a clay surface, or on top of an ordinary “fur coat”, which may well cause its rapid destruction.

Summing up, we can conclude that the selection of a suitable material for the insulation of any structure is a very difficult process, requiring heightened attention. Remember that in this matter, it is best to rely only on yourself and on your knowledge, since in most cases, store consultants can advise

You can buy high-quality expensive insulation where you can do without it (for example, under linoleum, or on internal walls). Therefore, make the choice yourself, based on the characteristics of the material, and on its quality. Also, it is important to remember that the price is not always an important criterion that you should focus on when choosing.

See the following video for an explanation of the thermal conductivity table of materials with examples:

The construction business involves the use of any suitable materials. The main criteria are safety for life and health, thermal conductivity, reliability. This is followed by price, aesthetic properties, versatility of use, etc.

Consider one of the most important characteristics of building materials - the coefficient of thermal conductivity, since it is on this property that, for example, the level of comfort in the house largely depends.

Theoretically, and practically too, building materials, as a rule, create two surfaces - external and internal. From the point of view of physics, the warm region always tends to the cold region.

In relation to a building material, heat will tend to move from one surface (warmer) to another surface (less warm). Here, in fact, the ability of the material with respect to such a transition is called the thermal conductivity coefficient or, in the abbreviation, CFT.

Scheme explaining the effect of thermal conductivity: 1 - thermal energy; 2 - coefficient of thermal conductivity; 3 – temperature of the first surface; 4 – temperature of the second surface; 5 - the thickness of the building material

The CHF characteristic is usually built on the basis of tests, when an experimental specimen with dimensions of 100x100 cm is taken and a thermal effect is applied to it, taking into account the temperature difference of two surfaces by 1 degree. Exposure time 1 hour.

Accordingly, thermal conductivity is measured in Watts per meter per degree (W/m°C). The coefficient is denoted by the Greek symbol λ.

Default, thermal conductivity various materials for construction with a value less than 0.175 W / m ° C, equates these materials to the category of insulating.

Modern production has mastered the technology of manufacturing building materials, the level of CFT of which is less than 0.05 W/m°C. Thanks to such products, it is possible to achieve a pronounced economic effect in terms of the consumption of energy resources.

Influence of factors on the level of thermal conductivity

Each individual building material has a certain structure and has a peculiar physical state.

The basis of this are:

• dimension of structure crystals;
• phase state of matter;
• degree of crystallization;
• anisotropy of thermal conductivity of crystals;
• volume of porosity and structure;
• direction of heat flow.

All of these are influencing factors. The chemical composition and impurities also have a certain effect on the level of CHF. The amount of impurities, as practice has shown, has a particularly pronounced effect on the level of thermal conductivity of crystalline components.

Insulating building materials - a class of products for construction, created taking into account the properties of PTS, close to optimal properties. However, it is extremely difficult to achieve ideal thermal conductivity while maintaining other qualities.

In turn, the KTP is influenced by the operating conditions of the building material - temperature, pressure, humidity level, etc.

Building materials with a minimum KTP

According to studies, dry air has a minimum value of thermal conductivity (about 0.023 W / m ° C).

From the point of view of the use of dry air in the structure of a building material, a structure is needed where dry air resides inside numerous enclosed spaces of small volume. Structurally, such a configuration is presented in the form of numerous pores inside the structure.

Hence the logical conclusion: a building material, the internal structure of which is a porous formation, should have a low level of CHF.

Moreover, depending on the maximum allowable porosity of the material, the value of thermal conductivity approaches the value of the CHF of dry air.

The porous structure contributes to the creation of a building material with minimal thermal conductivity. The more pores of different volumes are contained in the structure of the material, the better the CFT can be obtained.

In modern production, several technologies are used to obtain the porosity of a building material.

In particular, technologies are used:

• foaming;
• gas formation;
• water sealing;
• swelling;
• introduction of additives;
• creating fiber scaffolds.

It should be noted: the coefficient of thermal conductivity is directly related to properties such as density, heat capacity, thermal conductivity.

The thermal conductivity value can be calculated using the formula:

λ \u003d Q / S * (T 1 -T 2) * t,

• Q- The amount of heat;
• S is the thickness of the material;
• T1, T2– temperature on both sides of the material;
• t- time.

The average value of density and thermal conductivity is inversely proportional to the value of porosity. Therefore, based on the density of the building material structure, the dependence of thermal conductivity on it can be calculated as follows:

λ \u003d 1.16 √ 0.0196 + 0.22d 2 - 0.16,

Where: d– density value. This is the formula of V.P. Nekrasov, demonstrating the influence of the density of a particular material on the value of its CFT.

The influence of moisture on the thermal conductivity of building materials

Again, judging by the examples of the use of building materials in practice, it turns out the negative effect of moisture on the CTP of building materials. It has been noticed that the more moisture the building material is exposed to, the higher the value of the CFT becomes.

In various ways, they seek to protect the material used in construction from moisture. This measure is fully justified, given the increase in the coefficient for wet building materials

It is easy to justify this point. The impact of moisture on the structure of the building material is accompanied by air humidification in the pores and partial replacement of the air environment.

Considering that the parameter of the thermal conductivity coefficient for water is 0.58 W/m°C, a significant increase in the CTP of the material becomes clear.

A more negative effect should also be noted, when water entering the porous structure is additionally frozen - it turns into ice.

One of the reasons for the refusal of winter construction in favor of summer construction should be considered precisely the factor of possible freezing of some types of building materials and, as a result, an increase in thermal conductivity.

From here, construction requirements regarding the protection of insulating building materials from moisture ingress become apparent. After all, the level of thermal conductivity increases in direct proportion to the quantitative humidity.

Another point is no less significant - the opposite, when the structure of the building material is subjected to significant heating. Excessively high temperature also provokes an increase in thermal conductivity.

This happens due to an increase in the kinematic energy of the molecules that make up the structural basis of the building material.

True, there is a class of materials whose structure, on the contrary, acquires best properties thermal conductivity in high heating mode. One of these materials is metal.

If under high heat most of widely used building materials changes the thermal conductivity upwards, strong heating of the metal leads to the opposite effect - the CFT of the metal decreases

Methods for determining the coefficient

Different methods are used in this direction, but in fact all measurement technologies are combined by two groups of methods:

1. Stationary measurement mode.
2. Mode of non-stationary measurements.

The stationary technique involves working with parameters that are unchanged over time or vary slightly. This technology, according to practical applications, allows us to expect more accurate results of QFT.

Actions aimed at measuring thermal conductivity, the stationary method can be carried out in a wide temperature range - 20 - 700 ° C. But at the same time, stationary technology is considered labor-intensive and complex methodology requiring a lot of time to execute.

An example of an apparatus designed to perform measurements of the thermal conductivity coefficient. This is one of the modern digital designs that provides fast and accurate results.

Another measurement technology - non-stationary, seems to be more simplified, requiring from 10 to 30 minutes to complete the work. However, in this case, the temperature range is significantly limited. However, the technique has found wide application in the manufacturing sector.

Table of thermal conductivity of building materials

It makes no sense to measure many existing and widely used building materials.

All these products, as a rule, have been tested repeatedly, on the basis of which a table of thermal conductivity of building materials has been compiled, which includes almost all materials needed at a construction site.

One of the options for such a table is presented below, where KTP is the thermal conductivity coefficient:

Accurate data will allow you to get a table of thermal conductivity of building materials. Proper construction of buildings contributes to optimal climatic parameters in the room.

It is better to start the construction of each object with the planning of the project and careful calculation of thermal parameters. Accurate data will allow you to get a table of thermal conductivity of building materials. Proper construction of buildings contributes to optimal climatic parameters in the room. And the table will help you choose the right raw materials that will be used for construction.

Purpose of thermal conductivity

Thermal conductivity is a measure of the transfer of heat energy from heated objects in a room to objects with a lower temperature. The heat exchange process is carried out until the temperature indicators are equalized. To designate thermal energy, a special coefficient of thermal conductivity of building materials is used. The table will help you see all the required values. The parameter indicates how much heat energy is passed through a unit area per unit time. The larger this designation, the better the heat transfer will be. When erecting buildings, it is necessary to use a material with a minimum value of thermal conductivity.

The thermal conductivity coefficient is a value that is equal to the amount of heat passing through a meter of material thickness per hour. The use of such a characteristic is necessary to create the best thermal insulation. Thermal conductivity should be taken into account when selecting additional insulating structures.

What affects the thermal conductivity?

Thermal conductivity is determined by such factors:

Porosity determines the heterogeneity of the structure. When heat is passed through such materials, the cooling process is negligible;

An increased density value affects the close contact of the particles, which contributes to faster heat transfer;

High humidity increases this indicator.

Using the values ​​of the thermal conductivity coefficient in practice.

Materials are represented by structural and heat-insulating varieties. The first type has high thermal conductivity. They are used for the construction of ceilings, fences and walls.

With the help of the table, the possibilities of their heat transfer are determined. In order for this indicator to be low enough for a normal indoor microclimate, walls made of some materials must be especially thick. To avoid this, it is recommended to use additional heat-insulating components.

Thermal conductivity indicators for finished buildings. Types of insulation.

When creating a project, all methods of heat leakage must be taken into account. It can exit through walls and roofs, as well as through floors and doors. If you do the design calculations incorrectly, you will have to be content with only the thermal energy received from the heating devices. Buildings built from standard raw materials: stone, brick or concrete need to be additionally insulated.

Additional thermal insulation is carried out in frame buildings. Wherein wooden frame gives rigidity to the structure, and the insulating material is laid in the space between the uprights. In buildings made of bricks and cinder blocks, insulation is carried out outside the structure.

When choosing heaters, it is necessary to pay attention to such factors as the level of humidity, the effect of elevated temperatures and the type of structure. Consider certain parameters of insulating structures:

The thermal conductivity index affects the quality of the heat-insulating process;

Moisture absorption is of great importance when insulating external elements;

Thickness affects the reliability of insulation. Thin insulation helps to save the useful area of ​​the room;

Flammability is important. High-quality raw materials have the ability to self-extinguish;

Thermal stability reflects the ability to withstand temperature changes;

Environmental friendliness and safety;

Soundproofing protects against noise.

The following types are used as heaters:

Mineral wool is fire resistant and environmentally friendly. Important characteristics include low thermal conductivity;

Styrofoam is lightweight material with good insulating properties. It is easy to install and is moisture resistant. Recommended for use in non-residential buildings;

Basalt wool, unlike mineral wool, is distinguished by the best indicators of resistance to moisture;

Penoplex is resistant to moisture, high temperatures and fire. It has excellent thermal conductivity, easy to install and durable;

Polyurethane foam is known for such qualities as incombustibility, good water repellency and high fire resistance;

Extruded polystyrene foam undergoes additional processing during production. Has a uniform structure;

Penofol is a multilayer insulating layer. Contains polyethylene foam. The surface of the plate is covered with foil to provide reflection.

Bulk types of raw materials can be used for thermal insulation. These are paper granules or perlite. They are resistant to moisture and fire. And from organic varieties, you can consider wood fiber, linen or cork. When choosing, pay special attention to such indicators as environmental friendliness and fire safety.

NOTE! When designing thermal insulation, it is important to consider the installation of a waterproofing layer. This will avoid high humidity and increase resistance to heat transfer.

Table of thermal conductivity of building materials: features of indicators.

The table of thermal conductivity of building materials contains indicators various kinds raw materials used in construction. Using this information, you can easily calculate the thickness of the walls and the amount of insulation.

How to use the table of thermal conductivity of materials and heaters?

The heat transfer resistance table of materials shows the most popular materials. When choosing a particular option for thermal insulation, it is important to consider not only physical properties, but also such characteristics as durability, price and ease of installation.

Did you know that the easiest way is to install penooizol and polyurethane foam. They are distributed over the surface in the form of foam. Such materials easily fill the cavities of structures. When comparing solid and foam options, it should be noted that the foam does not form joints.

The values ​​of the heat transfer coefficients of materials in the table.

When making calculations, you should know the coefficient of resistance to heat transfer. This value is the ratio of temperatures on both sides to the amount of heat flow. In order to find the thermal resistance of certain walls, a thermal conductivity table is used.

You can do all the calculations yourself. For this, the thickness of the heat insulator layer is divided by the thermal conductivity coefficient. This value is often indicated on the packaging if it is insulation. Household materials are self-measured. This applies to thickness, and the coefficients can be found in special tables.

The resistance coefficient helps to choose a certain type of thermal insulation and the thickness of the material layer. Information on vapor permeability and density can be found in the table.

At correct use tabular data you can choose quality material to create a favorable indoor climate. published