One of the most high-quality and durable heat-insulating materials is considered to be foam glass. Due to its truly unique characteristics, this material has found its application not only in individual construction, but even in the construction of industrial facilities. However, for all its advantages, the insulator is not so popular in comparison with other heat insulators, and there are reasons for this. In addition to the mass of positive properties and characteristics, foam glass has significant disadvantages. Let's see what the disadvantages of foam glass do not allow him to become the first among thermal insulation materials.
Costly production
The problem is that cheap raw materials such as broken glass fragments or sintered rocks are used to produce this material, but the manufacturing technology itself is quite expensive. In order to obtain granulated foam glass, a temperature of the order of 800-900 degrees and molds made of heat-resistant steel are necessary.
- The manufacturing process consists first in heating and softening the glass powder obtained from raw materials.
- Then it is foamed by burning a blowing agent - as a rule, this is coal.
- After that, the material is slowly cooled, resulting in foam glass.
The production of insulation is a rather complicated and long process, due to which the cost of seemingly cheap raw materials increases significantly.
Foam Glass Products
The end result of the production are blocks having a cellular structure and granular foam glass. Due to the use of special forms, block products have a higher cost than the same volume of material in the form of granules.
Subsequently, the blocks are cut into slabs, which are used as thermal insulation on complex objects. For example, on roofs with a large area or structures of complex geometric shapes, as well as for thermal insulation of underground structures. It is convenient to use a foam glass plate as a thermal insulation for pools, bathtubs and other buildings in which a difficult temperature regime is operated, and all thanks to the special resistance of the material to water vapor.
Granular foam glass is used, as a rule, as bulk free thermal insulation on roofs or as a backfill for screed. The second application of this material is a filler for various solutions to obtain light screeds, plasters or blocks under the foundation.
Both products have the composition and characteristics of ordinary glass, so the advantages and disadvantages of foam glass are based on the properties of this material.
Strength properties of foam glass
This insulation is one of the most durable of all types of thermal insulation. However, we are only talking about compressive strength, which is important for heat-insulating materials, since the insulator, as a rule, is subjected to this very load. The special value of this parameter is due to the fact that with strong compression the insulation can lose part of its properties: its moisture resistance is violated, and the insulator begins to conduct heat.
Unlike foam and fibrous materials, which are designed only for small internal forces, which significantly limits their use in some situations, foam glass is absolutely not compressible, and this allows it to take part of the load.
Resistance to deformation
Foam glass is not deformed under the influence of gravity, which eliminates its sagging, shrinking or shrinkage. Due to this, the insulation does not require mandatory fastening to metal anchors or pins that can create cold bridges. The material can be easily glued to hot bitumen, polymer or concrete mastics and specialized adhesives.
But not all the strength characteristics of the insulation are so ideal. The disadvantages of foam glass are primarily based on the properties of the initial raw material, which has a low resistance to mechanical shock. Therefore, the blocks are easy enough to break or damage. Moreover, even small surface defects can lead to a decrease in moisture resistance and an increase in thermal conductivity.
Foam glass life
The life of the insulation is at least 100 years, which significantly exceeds the service life of most buildings without major repairs, where it can be used.
Foam glass was created back in the 30s of the last century, so today we can talk about the aging resistance of this material. Experts conducted experimental studies that showed that foam glass blocks did not lose their properties over an interval of 50 years and remained virtually unchanged.
However, this advantage is irrelevant in private construction, since low-rise buildings need reconstruction no later than 50 years later. Therefore, it is more advisable to use, although less durable, but cheaper heat-insulating materials than to use foam glass, the price of which is quite high (16,000 rubles / m 3 ).
Environmental resistance
In this case, we are talking about various kinds of influences of both chemical and biological nature. Thermal insulation materials from foam glass are not destroyed by chemicals, the only exception is hydrofluoric acid. But this can hardly be considered a drawback, since this reagent can only be detected in chemical production.
Since foam glass consists only of higher oxides of various elements, it is not exposed to oxygen contained in the surrounding air, and therefore, to oxidation.
Due to the same feature, the insulation is not subject to burning. When exposed to high temperatures, it melts like ordinary glass, while not emitting, unlike most heat-insulating materials, harmful gases and substances.
There is another factor that affects the fire safety of the material - this is the lack of absorbency. Foam glass fully possesses this property and is not an absorbent material.
Non-hygroscopicity of the material
Thanks to this characteristic, it does not affect the insulation and water, it does not matter if it is fresh or salty, since there are no soluble components in the composition, and the foam glass structure is closed cells into which moisture is simply not able to get into. Due to these qualities, the material is not destroyed under the influence of low temperatures. Therefore, insulation is often used as a waterproofing material.
In addition, foam glass, whose characteristics are identical to those of ordinary glass, has a low coefficient of thermal expansion, which means that it can withstand seasonal temperature differences without problems, regardless of the region of use. Another positive feature of the material is high-quality sound insulation, and all thanks to the dense structure of the foam glass.
Foam glass foamglas
However, the non-hygroscopicity and density of the material also causes some disadvantages of foam glass, in particular its rather large weight in comparison with other heat insulators. This significantly complicates the transportation of insulation, which significantly increases the sale price of the material. Yes, and installation is becoming a rather problematic event.
However, modern production allows us to correct this drawback. For example, Pittsburg Corning Corporation produces FOAMGLAS foam glass, which is characterized by extraordinary lightness, while retaining all the properties inherent in this material.
Therefore, today foam glass is mainly mounted on building mixtures, which simplifies the fastening of insulation. In addition, good adhesion of the material is also due to the good adhesion of the foam glass.
Biological impact
First of all, we note that foam glass is absolutely resistant to decay, the formation of mold and fungi, since its composition simply does not have a favorable environment for their reproduction. This factor is especially important during construction, when heat-insulating materials are often used in confined spaces. A similar property of foam glass allows you to guaranteedly avoid the destruction of both the heat insulator and the surface that it protects, whether it is a roof, a wall or a foundation.
It is also important that the foam glass cannot be damaged by the roots of plants. And also completely inaccessible to insects and rodents, due to abrasive properties. This feature of the material found its application in the arrangement of granaries, warehouses and food refrigeration facilities, when foamglass insulation is also an ideal protection against various biological forms.
What else are the advantages and disadvantages of foam glass?
In addition to the main characteristics listed above, the material has several more distinctive properties.
Foam glass is very easy to process and give it the desired shape using conventional cutting tools. This allows you to use this insulator for buildings of any geometric shape. But the industrial manufacture of blocks is a rather complicated process, leading to a significant enthusiasm for the cost of the material.
Heater-foamglass is an absolutely environmentally friendly material that does not have any harmful effect on human health. And more recently, it was produced using technology where hydrogen sulfide was used as a blowing agent. Its smell was transmitted to the finished material, so the use of insulation in private construction was quite limited due to the unpleasant smell of “rotten eggs”.
Due to its environmental friendliness, foamglass today is becoming one of the most popular heat-insulating materials, in addition, after use, the insulation can be recycled into a new product once again.