Foam glass is produced in mats, blocks, shells and loose.
In the previous article, we talked about , which, after many years of neglect, returns to the building materials market again. But, like all natural insulation, it is not without drawbacks, such as moisture absorption and rodent attacks. And if in everyday life it is still possible to somehow smooth out these factors, then such material is not applicable to large objects. Something more fundamental is needed here, like foam glass. Insulation made from broken glass has high performance characteristics, allowing it to be used in the construction of multi-storey buildings and industrial facilities.
Types of foam glass insulation
Foamed glass insulation was developed by Soviet scientists in the 30s of the XX century. At that time, the production technology was considered too expensive and the project was postponed indefinitely. And finally, this material has found its application in construction. It is made from glass waste, which is a definite plus.
Broken glass is ground into powder, mixed with a foaming agent (coal, coke, marble, limestone) and brought to a liquid state by heating to 800-900 degrees.
At this temperature, a reaction occurs with the release of carbon dioxide, the bubbles of which are evenly distributed over the liquid mass. As a result, after cooling, a solid material with a closed-cell structure is obtained. It looks like hardened soap suds, where all the bubbles are made of glass. Foamed glass insulation is in the form:
- slabs;
- blocks;
- shells;
- granules;
- rubble.
Foam glass is suitable for insulating walls, floors and horizontal roofs. The material is absolutely environmentally friendly and can be used even in rooms with high sanitary requirements (hospitals, kindergartens, laboratories, etc.).
Features and prices of foam glass
Foam glass in granules can be of different fractions.
As you know, air is one of the best heat insulators, and foam glass contains abundant amounts of it. The thermal conductivity properties of the material are inferior to modern heaters, but in terms of reliability it has no equal. According to the manufacturers, the service life is at least 100 years. At the same time, the possibility that mice, fungus or other beetles will start in the insulation is excluded. Also, the material does not react with any chemical element.
Foam glass properties:
- water absorption from 0 to 5% of the total volume;
- resistance to heat conductivity 0.04-0.08 W / m * K;
- steam conductivity no more than 0.0005 mg / m * h * Pa;
- compressive strength up to 4 MPa;
- bending strength 0.6 MPa;
- operating temperature from -250 to +485 degrees.
From the characteristics, we can conclude that the material is strong enough, although it does not withstand impacts. Insulating qualities are certainly not the ultimate dream, but resistance to various kinds of chemical aggression smoothes the situation. And another significant plus is that mice do not gnaw foam glass. Heaters, according to reviews, are very susceptible to attacks by rodents, they start even in Soviet glass wool, which is incredibly prickly. In order not to put up with this, foam glass is ideal.
Due to its technical characteristics, this material has the following properties:
- mechanical strength;
- lack of volumetric expansion and shrinkage;
- incombustibility - melting point 1 thousand degrees;
- does not allow water and steam to pass through;
- quite heavy - density from 110 to 200 kg / m3. cube;
- high price.
Prices in Moscow for foam glass insulation, according to reviews, practically do not differ from the all-Russian level. Therefore, it is obvious that the inhabitants of the provinces, where the average per capita income is very low, cannot afford to insulate their homes with this material. The cheapest will be granules or crushed stone, the price of which varies in the range of 2-3.5 thousand rubles per cubic meter. Foam glass in products (plates, blocks, shells) cost about 5.5-7.5 thousand rubles per cubic meter and this is at a minimum, in some places it reaches 15 thousand rubles per 1 cubic meter.
Foam Glass Applications
Foam glass is easily cut with a hacksaw for metal or a saw for foam blocks.
Wherever foam glass is not used. The use of this material is possible for insulation:
- walls;
- ceilings;
- floors;
- flat roofs.
In this case, both blocks and granulated foam glass are used. The application of the latter has a wider spectrum. Granules are poured into the voids of brick walls, screed is made of them, they are even plastered with them. Foam glass insulation is also used for and other communications.
This material is mainly used in large areas when building multi-storey buildings or industrial facilities. It is rarely used by individuals, since it is quite expensive and in everyday life, the insulation does not experience high loads, therefore, they completely manage with the same foam or. Foam glass insulation of a frame house is not practiced for a number of reasons. Such houses are positioned as budget houses, otherwise who would build them?
It makes no sense to use such an expensive insulation in a budget house. Even if we hypothetically allow this option, then the problem of the large weight of the material arises. In order for the floors to withstand the additional load, the frame must be assembled from a thicker timber, which again leads to additional costs. For the same reason, granules cannot be poured into hollow walls, and covering the walls from the outside is the same as covering a frame with a brick - sheer nonsense.
The technique of foam glass insulation of walls and floors
Foam glass plates are glued to the wall and then attached to plastic dowels.
Considering the insulation of a house with foam glass is necessary only from the perspective of fundamental buildings (brick, foam blocks, monolith). Walls can be insulated both outside and inside. In addition, insulation is possible in the middle of the wall, between two rows of masonry. Dry granules are simply poured into the space between the walls during the construction of the walls. External wall insulation with foam glass, according to reviews, is performed using glue and plastic dowels. Method of work:
- preparatory work - leveling the wall, applying a primer;
- glue is applied to the foam glass blocks;
- blocks are glued to the wall, starting from the bottom;
- each block is secured with one dowel.
It is necessary to lay blocks against the wall and on top of each other according to the principle of ordinary brickwork, that is, with a half-stone shift.
Thus, the structure will be solid. Plaster can be applied over foam glass blocks. By the way, there are modern dry mixes for plastering walls, which include small (about 1 mm) capsules of foam glass. This is the so-called warm plaster, the application method of which does not differ from ordinary plaster.
There are two options for insulating the floor with foam glass:
- plates;
- granules.
It is more practical and faster to make a screed from foam glass granules. To do this, you need to make cement milk and mix it with granular material. Lighthouses are preliminarily placed on the floor according to the level. The resulting solution is poured between the guides and evenly distributed with a wire. After hardening, tiles can be laid on the foam glass screed. A visual technique for insulation with foam glass, video:
Anyone who follows the achievements of construction science will never fail. It is here that lies a powerful resource for reducing costs, increasing energy efficiency, quality and speed of housing construction. A good example is foam glass.
This interesting material with great potential can only be conditionally called a novelty in the construction market. It was invented in the 30s of the last century in the USSR, and its practical application was invented later - in 1946 in Canada. Foam glass went into mass construction only half a century later, when the costs of its production were reduced and the technology was thoroughly worked out.
What is foam glass?
The combination of two different substances in one material always gives an interesting result. This happened with foam glass. The classic silicate glass that stands in our windows is a transparent, very hard and fragile material. Foam is a weightless, “ephemeral substance”. Its basis is gas, the bubbles of which are held together due to the thinnest layers of liquid by the force of surface tension.
You ask, is it possible to combine the incompatible? It turns out you can. The production of foam glass consists in heating a silicate mass, into which a gas-forming substance is introduced. Under the influence of high temperature, the raw material melts, and the gasifier decomposes, releasing the smallest bubbles. Caught in the hot melt, they are like "flies in amber" forever remain in it.
As a result, the material receives unique properties:
- Ease;
- Strength;
- Chemical inertness;
- Waterproof;
- Heat resistance and incombustibility.
Some of the listed properties are inherited by the material from silicate glass, and part of it is derived from gas microcapsules. Foam glass loses its transparency, but it acquires excellent thermal insulation and acoustic characteristics.
Specifications
The density of the foamed glass is very low (100-250 kg / m3). How small this is, you can judge by comparing it with the density of dry wood (550-750 kg / m3). It is no coincidence that after the invention, foam glass was tried to be used as a floating building material.
The compressive strength of such a light substance is surprisingly high. It can withstand pressure up to 40 to 100 tons per 1 m2. The rest of the technical characteristics of foam glass also inspire optimism for everyone who plans to use it.
Thermal conductivity at room temperature - 0.04 W / m * C. Even dry coniferous wood retains heat twice as bad (0.09 W / m * C). The ability to damp sound waves in cellular glass is comparable to mineral wool (45-56 dB).
Water absorption of foam glass blocks - 2% of the volume. In a more understandable language, they practically do not absorb water. Their vapor permeability is close to zero (0.005 mg / (m.h. Pa). This is an ideal rigid vapor barrier.
In terms of resistance to high temperatures, the foam glass also looks decent. Of course, this is not chamotte, but even a standard porous glass block can withstand + 300C without signs of destruction. Special additives raise the thermal resistance of the material to +1000 C. Foam glass is not afraid of low temperatures, withstanding extreme contact with liquid nitrogen (-200 C).
A very valuable quality of this material is its high chemical inertness and the associated environmental friendliness. There are few modern insulation materials that are just as safe and non-toxic. Polymer compounds age rather quickly, losing their physical qualities and poisoning the environment. Polymers and flammability, organic insulation and toxicity are almost synonymous. From this point of view, foamed glass is much better than expanded polystyrene, polypropylene and PVC plastics.
Durability is another plus that aerated glass attracts developers. The service life of 100 years speaks for itself.
The biological resistance of glass foam blocks is incomparably higher than that of organic insulation. It is too tough for rodents. Mold and mildew will also not find a cozy place in it, since the material does not absorb water.
The chemical inertness of foamed glass is very high. Acids and alkalis, corrosive gases and oil products - all together and each separately, they will not cope with such a heater.
It will not take long to list the disadvantages of foam glass... The high price is what confuses ordinary developers in the first place. It is explained by the fact that the manufacturing technology of this material is associated with high energy costs. Its annealing (slow cooling) is a complex and laborious process. If we evaluate blocks of foamed glass in terms of price-durability ratio, then they will benefit in comparison with similar indicators of other heaters.
The second drawback is low impact strength. It cannot be called critical, since the insulation in the structures does not experience impacts, and the streets are not yet paved with foam glass.
Application
Especially valuable is the fact that cellular glass combines high strength and heat-insulating ability.
We are all accustomed to the fact that the harder the material, the more it conducts heat. The opposite is true here. It is a tough, effective insulation that can be driven by a truck. Therefore, the use of foam glass is primarily associated with the thermal insulation of load-bearing walls, basements and pipelines.
Cellular glass has a coefficient of thermal deformation close to that of concrete and brick, so it can be used for revealing any types of structures made of these materials.
Due to its low water absorption, foamed glass is ideal for waterproofing basements and basements of buildings. This positive point is most often noted in consumer reviews.
In addition to block glass, they produce granulated foam glass. It is cheaper than a monolith and is used as a heat-insulating additive in concrete, as well as backfill in wall cavities.
Despite its high mechanical strength, foamed glass is easy to process. It is drilled and cut without cracking, easily glues and holds the finishing compounds (putty and plaster) well.
Foam glass is used not only for insulating building structures. It can be found in the housings of industrial refrigerators and technological equipment operating at elevated temperatures.
The foam glass exterior is also noteworthy. In addition to the original look, it reliably solves the problem of protection from aggressive atmospheric factors (cold, heat and precipitation).
Attention! Low-quality "analogues" of foam glass
Speaking about this material, one cannot fail to mention its cheap "analogue", also called foam glass from the light hand of manufacturers. In fact, it is made not from standard solid raw materials by firing, but from liquid sodium-potassium glass.
Substances that actively absorb water are added to this substance. As a result, the liquid glass foams and then hardens. The process takes place at a temperature of +100 - + 200C. Even an inexperienced person understands that such a material, in principle, cannot be durable and waterproof. In fact, this is a regular stationery glue with gas bubbles.
At the slightest soaking, it flows, and in terms of mechanical strength it is tens of times weaker than the classical porous material. Therefore, insulation with foam glass of this type (sometimes called "vapor-permeable") cannot be called beneficial.
The only plus that manufacturers are trying to attract consumers with is low cost (2-3 times lower than that of ordinary foam glass).
Estimated prices
Speaking about the prices for foam glass, we will single out three main forms of its production. This material is produced in blocks, slabs, in the form of shaped products (volumetric shells) and chips (granules and crushed stone).
Block and slab foam glass is used as a rigid waterproofing insulation. Cellular glass shells are used to insulate pipelines. Granules go to heat-insulating backfill, and are also used as a filler for plaster mortars and lightweight concrete.
The most common size of aerated glass slabs is 600x450 mm. Their thickness ranges from 3 to 12 cm (1 cm step).
Block and shaped material has the highest cost. Depending on the manufacturer, it can be purchased at prices ranging from 9,000 to 16,000 per m3.
The cheapest are chips (fraction 0-7 mm) and crushed stone (8-20 mm) from foamed glass, since they belong to the category of technological waste. They can be purchased at a price of 5,000 rubles / m3.
Modern technologies are constantly being improved - new ones come to replace the old ones. The construction industry is no exception, which, like no other, is subject to constant changes. Modern building materials and technologies appear with enviable regularity - people did not have time to get used to the process of foam insulation, as foam glass replaced it. What kind of animal is this, and how to handle it? It is with this question that we will deal with today on the pages of the website "Dream House".
What is foam glass and where is it used
As you probably already understood from the above, foam glass is the latest development in the field of energy-saving technologies. Moreover, today it is simply impossible to find insulation for walls, floors or roofs better than foam glass. This material has an almost zero coefficient of thermal conductivity - to be precise, at a temperature of + 10˚C it is only 0.041W / m2.
It is made at very high temperatures, so the production of foam glass at home is impossible. In the manufacturing process, this material goes a rather long way - first, the glass is crushed almost to the consistency of dust, then it is saturated with carbon dioxide, and already in this form is fed into the oven, where at a temperature above 750˚C many small and sealed glass bubbles form. Subsequently, from the resulting mixture, either the usual blocks or granules are formed.
Foam glass is used in different ways. Block material is used for wall insulation - it is laid inside the wall during construction. A kind of layer cake is created, consisting of a facing layer, insulating and rough (inner). If we talk about granular foam glass, then it can be used both for wall insulation and for floor and flat roof insulation. Even the foundation of the building is insulated with it. Such a universal insulation could only be dreamed of before.
In addition to direct insulation of buildings, foam glass is used for thermal insulation of all kinds of pipelines. Modern technologies make it possible to make it in almost any way, including in the form of a shell for pipes. Moreover, they make not only straight sections, but also turning ones.
Granulated foam glass is also successfully used as a filler in the manufacture of lightweight concrete structures.
Foam glass and its properties: advantages and disadvantages
As the saying goes, everything is learned by comparison. Therefore, we will try to analyze the foam glass and compare it with other similar heaters. As an alternative to it, we will take similar in purpose - aerated concrete and expanded clay.
- Water and vapor tightness... Unlike foam glass, both of its competitors absorb moisture - aerated concrete to a greater extent, and expanded clay to a lesser extent. What are the advantages of this property to foam glass? Firstly, when using certain adhesives, it can be used as a waterproofing. Secondly, it can be used outdoors without additional protection.
- Soundproofing... A block or layer of foam glass in the form of a crumb 100 mm thick is capable of completely drowning out sound with a power of up to 56 dB. Neither more nor less, and you can barely discern the roar of the tractor engine behind such protection.
- Antiseptic... If special, by no means harmless impregnations are used to impart these properties to foam and mineral wool, then foam glass itself is an antiseptic. In this respect, it surpasses even aerated concrete and expanded clay, in which all kinds of insects live freely.
- Resistant to most types of acids... Our alternative heaters - both aerated concrete and expanded clay - are completely devoid of this advantage. Almost all modern thermal insulation materials are subject to destruction under the influence of aggressive acids.
- Incombustibility... It is difficult to talk about the ignition temperature of this material, because above 750˚C, it just starts to soften. Foam glass can be called generally non-combustible material - it can become liquid, but practically unable to catch fire.
- High compressive strength... The principle of joint resistance to loads operates here. In this respect, foam glass can be compared to plywood - one layer of it is easy to break, and ten layers can withstand enormous loads. The same happens with foam glass - millions of tiny balls are able to withstand loads up to 4MPa per 1 sq. Cm. This is enough for the foam glass wall to withstand the weight of the concrete floors.
- Ease of processing... The process of warming with foam glass can be compared with laying aerated concrete - both are quite easily cut with an ordinary hacksaw on wood.
- Environmental friendliness... This property is highly valued in the modern world. This material contains nothing but glass and carbon dioxide residues.
But this insulation has practically no drawbacks. These include only the high cost - today, foam glass is the most expensive thermal insulation material.
How to work with foam glass
Despite the complexity of the production process, working with foam glass is quite simple. In this respect, it is no different from the same aerated concrete or expanded clay. Block foam glass is laid in almost the same way as aerated concrete - specialized glue is used for this. Depending on the purpose of the masonry, foam glass glue can be used in different ways. Foam glass in the form of granules is used as a bedding for a floor screed or a filler for lightweight concrete - in this respect, it is completely similar to expanded clay.
Whatever one may say, but better than foam glass, it is almost impossible to find a heat-insulating material today.
Foam glass- modern heat-insulating material obtained by processing silicate glass and a blowing agent (usually coal, anthracite, coke, soot) at high temperatures, about 1000 ○ С.
The foaming process is accompanied by an increase in the volume of glass 14 ... 15 times, compared with the original. In European countries, foam glass materials have long been recognized and one of the most effective heat-shielding building materials.
Thermal insulation material - foam glass: characteristics and scope
The thermal insulation properties of foam glass are due to the presence in its structure of a huge number of closed bubbles filled with air or carbon dioxide. Foam glass materials consist only of glass and gas (air, carbon dioxide) and their chemical composition is identical to the composition of ordinary glass we use in everyday life:
- silicon oxide;
- calcium oxide;
- magnesium oxide;
- potassium oxide;
- sodium oxide;
- aluminium oxide.
The structure of the foam glass looks like a honeycomb (photo 1), which ensures a relatively high strength of the material, taking into account the small size of the bubbles and the thickness of their walls (the average diameter of the bubbles is 2000 µm, and the thickness of the walls of the bubbles is 20 ... 100 µm).
Foam glass, as a heat-insulating material, has been developed for a long time and has been industrially produced since the 50s ... 60s of the last century. Initially, due to its high cost, this material was not widely used. Only after the improvement of production technology, the reduced cost of foam glass gave it a "second wind", although now its cost is also not cheap. Foam glass possesses high physical and chemical properties, which lead to a constant growing demand.
Here are the main characteristics of foam glass
- thermal conductivity of foam glass - 0.045 ... 0.060 W / m ∙ K;
- material density - 120 ... 140 kg / m 3 (relatively light heat-insulating material);
- the material is airtight;
- water absorption - no more than 2.5 ... 5% or surface absorption - no more than 0.5 kg / m 2;
- water insoluble material;
- ultimate compressive strength - 0.4 ... 1.2 MPa, and some blocks of foam glass can have a strength of 4 ... 24 MPa (depending on the brand of foam glass);
- the material is vapor-tight;
- modulus of elasticity - 800 MN / m 2;
- noise absorption - up to 60 dB (it is determined that a wall thickness of 10 cm from foam glass is able to isolate a room from a noise volume of up to 56 dB);
- operating temperature range of foam glass material - from -200 ○ С to +500 ○ С;
- foam glass is a non-combustible material (in the middle of the last century, roofs and ceilings of very important buildings were insulated from foam glass: nuclear power plant buildings, high-class hotels, to which particularly high fire safety requirements were imposed);
- insulation resistant to chemicals;
- ecological material (non-toxic), does not emit harmful substances, including at high temperatures in the event of a fire;
- bio-resistant material (not food and shelter for rodents, insects, insects), the material does not rot;
- low coefficient of thermal expansion (0.9 · 10 -6 K);
- the material does not shrink;
- the material is not hygroscopic (does not get wet when in a humid environment);
- has high adhesion to most building materials: plaster mortars, concrete, bituminous mastics, etc.;
- high durability (over 100 years).
The main feature of foam glass consists in the fact that this material possesses unchanged high thermal properties, which do not change practically throughout the entire period of its operation. So tests of building materials made of foam glass after 50 ... 60 years of operation have shown that its characteristics have not changed at all, which cannot be said about many other heat-insulating materials.
In practice, this material has no drawbacks, except for one - high cost (in comparison with other heat-insulating materials).
Foam glass building materials are manufactured in the form:
- slabs with dimensions: width - 450 mm, length - 600 mm, thickness - 60, 80, 100, 120 mm;
- blocks of size: 125 ÷ 450 × 125 ÷ 550 mm, thickness 20 ÷ 120 mm;
- crumbs (spherical granules).
Thermal insulation blocks and foam glass plates - area of application
With the help of foam glass slabs and blocks, they perform sound and thermal insulation of plinths, blind areas, foundations, various underground structures, insulate the facade, internal and external walls of high-rise buildings and structures, roofs (flat, pitched), photo 3.
Scope of foam glass
Table one provides useful data on the size of foam glass blocks, their mass and volume.
Foam glass crumb - scope
The crumb is produced from the same raw materials as blocks or slabs in the form of granules of various fractions: 0 ... 5 mm; 5 ... 7 mm; 7 ... 20 mm.
The crumb is produced directly, or is formed by cutting large foam slabs into blocks. The crumb is used as a bulk thermal insulation material in the construction of external walls with an interlayer and insulation of old houses. Also, with the help of foam glass crumbs, they insulate floors and roofs, photo 4, 5.
Foam glass crumb
Also, foam glass is used for insulating pipelines with a diameter of up to 1420 mm, transitions, tees, with a heating temperature of up to 500 ○ С, photo 6.
And in conclusion, instead of a conclusion, we will give comparative characteristics of some heat-insulating materials and foam glass in order to truly appreciate this unique material (see. tab. 2).
Alexander A. Konev
