What is expanded clay, how is it produced, the types of insulation, its technical characteristics, pros and cons, features of choice and a short DIY installation guide. In addition, there are about a dozen brands of expanded clay on the construction market. The classification is carried out according to the indicator of the bulk density (from 250 to 800). It, depending on the size and shape of the fractions, is determined in special measuring containers. Larger granules have the lowest bulk density.
The 700 and 800 brands cannot be found on the market. As a rule, they are produced on an individual order, since they have not received widespread use.
Technical characteristics of expanded clay
The properties of this insulation are established by domestic GOSTs, which regulate the quality of building materials with a porous structure. Consider the main characteristics of expanded clay:
- Strength of expanded clay … This indicator for the material is different and fluctuates depending on the type and brand. For example, for gravel with a density of 100, the compressive strength is 2-2.5 MPa. And for crushed stone with the same density, this indicator is 1, 2-1, 6 MPa. It is also worth noting that the strength increases as the density of expanded clay increases.
- Compaction factor … This value for a quality insulator should not exceed 1, 15. It should be taken into account during transportation and long-term storage of the material.
- Thermal conductivity of expanded clay … This indicator for the material is 0.1-0.18 W / (m * 0С). A layer of this insulation of 25 centimeters is equivalent to a layer of expanded polystyrene with a thickness of 18 centimeters. And an expanded clay mound of 10 centimeters retains as much heat as a meter-long brickwork or 25 centimeters of wood. The higher the density of the material, the lower its thermal insulation qualities. This is because the number and size of pores are reduced. Namely, they contain air - the main heat insulator.
- Moisture absorption … Expanded clay is a relatively water-resistant material. The water absorption coefficient is 8-20%. However, this only applies to insulation, which has a burnt crust. It is she who does not allow moisture to pass into the pores. If there is no such "protection", then expanded clay absorbs water very well, increasing its weight and losing its insulating properties.
- Soundproofing … This insulation has good sound insulation and noise suppression performance. The material optimally copes with the absorption of sounds when laying on interfloor floors. If there is someone running or making noise on the top floor, you are unlikely to know about it. True, soundproofing with expanded clay will be effective only if the floor surface does not touch the insulation layer, since the friction of the material granules is not at all silent.
- Fire resistance … Expanded clay is, in fact, burnt clay. Numerous tests have proven that the material does not burn in a fire and does not emit any harmful substances into the air when exposed to fire.
- Frost resistance … Expanded clay is not afraid of low temperatures, as well as their fluctuations. It is based on a frost-resistant material - clay, and thanks to a special production technology, it absorbs water very poorly, which means it will not collapse when water expands in its pores.
- Chemical resistance … Clay is a chemically inert substance, and therefore does not react with most building materials and solutions of acids, alkalis, and alcohols.
- Biological resistance … Mold, fungus do not multiply in expanded clay. Also, this material does not attract rodents and insects. In it, they do not arrange nests and holes.
- Environmental friendliness … Expanded clay is a pure natural insulation that does not emit any toxic compounds during installation and operation.
Advantages of expanded clay
This insulation has been used for many years and does not lose popularity, since it is difficult to find equals in terms of price-quality ratio. Consider the main advantages of expanded clay:
- Excellent thermal insulation properties … Clay belongs to the category of "warm" natural materials, and due to the presence of air in the structure of expanded clay granules, thermal conductivity decreases. This heat insulator is able to save up to 80% of heat loss.
- Light weight of expanded clay … The material is 10 times lighter than concrete. Only foamed polymers have less weight among heaters. Therefore, it will not exert too much load on the floors, the foundation, the roof.
- Relatively low price … Expanded clay is cheaper than many other heaters. And for its installation, no special tools and a team of professional builders are required. All work can be done independently.
- Environmental friendliness … Expanded clay is an absolutely natural insulation. It is recommended for use in residential buildings that are built using the "green house" or "eco-house" technology.
- Incombustibility … The material does not burn, does not support combustion, and does not emit toxic smoke when released into an open fire source. It is absolutely fireproof.
- Ease of installation … Even a beginner can make expanded clay mound. And since the heat insulator is relatively lightweight, it is quite possible to cope with it alone.
- Long service life … It is possible to use expanded clay as insulation for a very long time (100 years or more), but only if it is correctly installed.
Disadvantages of expanded clay
Despite the abundance of advantages, expanded clay also has certain disadvantages. They are especially manifested in the event that a low-quality insulation was chosen or the installation was carried out incorrectly.
Disadvantages of expanded clay:
- Requires underlay when laying horizontally … This is due to the fact that the material is quite dusty. This is especially true when installing expanded clay on wooden floors.
- Absorbs moisture in the absence of a protective "crust" on the granules … When wet, such expanded clay becomes unsuitable as insulation. The material dries up for a long time. Therefore, it is recommended to put a special waterproof layer on top of the hygroscopic insulator.
- A thick layer of insulation "eats" the height of the room … In order for heat and sound insulation to be of high quality, it is necessary to lay expanded clay with a thickness of at least 10-15 centimeters. Ideally, up to 40 centimeters.
Criteria for choosing expanded clay
It is necessary to choose this insulation, focusing on certain properties and quality. You can judge the characteristics of the material by the markings on the packaging. The bulk density of expanded clay and the grade are usually indicated there. In addition, when buying insulation, consider the following recommendations:
- Contact either the plant where the expanded clay is produced, or an official representative. Don't buy goods from dubious sellers, tempted by a low price. Its quality can be very low.
- Ask the seller to provide quality certificates for the insulation. Expanded clay is manufactured in accordance with GOST 9757-90. Only in accordance with this standard, high-quality clay is used and all firing standards are observed.
- Pay attention to the conditions in which the material is stored. It should be kept in a warehouse indoors, but not outdoors, where it can become damp and lose its properties.
- Check the integrity of the expanded clay fractions. A high-quality heat insulator should have as few broken granules, crumbs, sand as possible. In general, the amount of spoiled material should be no more than five percent.
- The color scale of high-quality expanded clay should be the same for all fractions: a shell of a dark brown hue and a dark (almost black) break.
Price and manufacturers of expanded clay
There are a large number of factories in Russia that produce expanded clay. Material of different fractions is manufactured by Keramzit CJSC (Moscow Region), Stoilensky GOK OJSC (Stary Oskol), Beskudnikovsky Building Materials Plant OJSC (Moscow), Kushvinsky Keramzite Plant CJSC (Sverdlovsk Region), Keramzit CJSC (Leningrad Region), Yakovlevostroydetal LLC (Belgorod Region), KSM Enemsky CJSC (Republic of Adygea). These businesses have received good reviews from consumers. The price of expanded clay is approximately the same for all manufacturers. It differs depending on the size of the granules.:
- 0-5 mm … Placer - from 2300 rubles per cubic meter. In bags - from 2500 rubles per cubic meter.
- 5-10 mm … In bulk - 1800 rubles per cubic meter. In bags - 2200 rubles.
- 10-20 mm … Scattering - from 1300 rubles. In a bag - from 1,500 rubles.
- 20-40 mm … Scattering - from 1300 rubles per cubic meter. In bags - 1,500 rubles and more.
Brief instructions for the installation of expanded clay
The technology of insulating the floor, foundation, ceiling or roof with expanded clay is generally similar. Let's consider it step by step:
- We align the base. If this is a floor, then you can fill in a not thick layer of cement mortar. We are waiting for complete drying.
- We lay the vapor barrier. This can be, for example, glassine. We glue the joints with tape.
- We install logs from wooden beams. We observe horizontalness using a building level.
- We fasten the bars with self-tapping screws in 50 centimeters increments.
- Pour expanded clay into the space between the logs with a uniform layer. We make sure that the insulation is flush with the surface of the lags.
- Next, we cover the structure with waterproofing, for example, a polyethylene film.
- On the finished surface, you can lay boards, slabs, gypsum board, pour the screed.
In the process, it is allowed not to build a structure from lags, but it will be more difficult to check the evenness and uniformity of the expanded clay layer. Watch a video review of expanded clay:
Expanded clay is a natural eco-friendly insulation, which is widely used in private and industrial construction. It can be used to carry out high-quality thermal insulation of floors, roofs, roofs, floors and even walls. The material has high thermal insulation properties and is resistant to external influences.
