When planning and carrying out construction work, it is important to select building materials that are economically beneficial, providing the building with a comfortable microclimate, with excellent operational and technical data, and the installation of which does not cause difficulties. This equally applies to foam and gas blocks. Consider each of the blocks, talk about the features, advantages and weaknesses of each of them.

What is better for construction

The gas block and foam blocks are similar in structure, the differences between which, according to multiple reviews, are not significant. This is a stone on an artificial basis, for the production of which cellular concrete is used. The basis of the material is environmentally friendly and safe, both for humans and the environment.

For foam concrete, a mixture of cement and sand is used, adding a special foaming agent to it. Hardening proceeds naturally, which allows the production of foam blocks even in the conditions of a house under construction or another facility - at a construction site. The material has a variable composition of raw materials, and it itself is characterized by a short period of storage. The finished product offers changeable technical parameters, which in no way interferes with the construction of walls or partitions.

Aerated blocks in the manufacture require special conditions: high humidity and high temperature conditions. Water, sand, lime, cement base are released from the components. The role of the blowing agent is performed by aluminum powder or paste. According to experts, the reagent does not emit harmful substances, it is environmentally friendly and safe.

The latest technologies give the material a uniform structure, the properties of which are unchanged. It turns out a material with a long service life and excellent characteristics, not prone to burning, easy to process, which is used in the construction of houses, baths, garages and other objects.

difference between materials

Despite the similarities, there are also differences. Various technologies are used for manufacturing. For foam concrete, mechanical mixing of a liquid concrete mixture with the foam obtained by mixing water and a foaming agent is used.

The resulting composition is subject to pouring into forms, which are group or individual. The exposure period is 4-8 hours, which makes the products stronger and allows you to dial the required parameters. Blocks are removed from individual molds, they gain tempering strength, the value of which is up to 70%. Blocks from group shapes are cut to give nominal dimensions - this option is better than the previous one and is characterized by high dimensional accuracy.

Aerated concrete is obtained by mixing the concrete composition with aluminum-based powder or paste. For 1 cubic meter solution requires 400 g of powder. As the mixture is stirred, a chemical reaction is activated, as a result of which a special substance is formed that "carbonates" the solution. For the manufacture of 2 cubic meters of aerated concrete, 1 cubic meters of solution is required. The composition gains strength in a few hours - in this aspect it is no different from foam concrete. After that, the blocks are cut to the required dimensions and sent to the autoclave for final hardening.

When comparing materials, it is worth noting the difference in hygroscopicity parameters. The gas block has a high value for this parameter, which makes building a house based on it a little more problematic, and the material itself requires additional external finishing.

You can distinguish the blocks by their appearance - the gas block is characterized by a white color, and the foam block is gray, and its surface is rough.

The method of docking differs, and for each of the blocks - the edges are straight or tongue-and-groove for a reliable connection.

Prices and costs

Let's compare prices. In some situations, this is almost a determining parameter when choosing in favor of a particular block. The cost of aerated concrete is on average 20% more expensive than foam concrete, and the monolithic format is even cheaper.

From the standpoint of cost, foam blocks are more profitable, but a full-fledged construction of an object only from them is impossible. It is better to choose a combined option with supporting structures made of aerated concrete and non-bearing elements based on foam blocks. The thermal conductivity of such a building will be at a high level, it will be warmer, stronger than made from one material.

Application area

It remains to figure out how each of the considered materials is used. The structure of gas blocks is characterized by uniformity, they are lighter than other similar materials, frost-resistant and not afraid of fire. This allows them to be used in the construction of load-bearing walls and partitions in the private construction sector. When filling frames in monolithic structures, this is the most profitable and justified solution - from a technical and economic point of view.

The foam block has a little more weight, it has a longer service life. Strength indicators differ, determined by the ratio of ingredients during kneading. The foam block is relevant for the arrangement of fences, partitions and load-bearing walls, provided that the height does not exceed 3 floors.

Advantages and disadvantages of each of the materials

Among the advantages of the foam block:

• Trouble-free production;
• The cost of manufacturing is cheaper than that of aerated concrete;
• Laying with the use of inexpensive cement;
• Installation takes a minimum of time.

As for the disadvantages, they are as follows:

• The faces of the blocks do not have a clear geometry;
• Inconstancy of the composition and its concentration;
• Significant consumption of cement during laying;
• The erected structure requires mandatory reinforcement.

The gas block offers the following benefits:

• Top notch workmanship;
• High strength;
• Resistance to influences and influences;
• Engagement at construction sites without restrictions;
• Reinforcement is required only partial.

Cons of gas blocks:

• Slightly more expensive cost;
• Large indicators of hygroscopicity;
• Heavier in production;
• Laying is carried out using building glue.

The choice in favor of a particular type of blocks is determined by the conditions of construction and the features of the structure being built, as well as the preferences of a particular consumer and financial capabilities.

With the development of the idea of ​​energy saving, alternative building materials, in particular wall blocks, received a rebirth. For the construction of walls, foam blocks and gas blocks, which are varieties of cellular concrete, are increasingly being used.

Their main similarity is the porous structure, which improves performance in comparison with classic ceramic bricks.

Foam concrete block - an artificial stone with a porous structure, consisting of sand, cement, water and a synthetic foaming agent.

Aerated concrete block - a cellular artificial stone, consisting of cement, quartz sand, blowing agent (aluminum paste or suspension), water, gypsum or lime.

1. Foam block and gas block: what is the difference?

Already from a short definition of the concepts, it can be seen that, despite the similar composition, the materials have a significant difference in manufacturing technology. Hence the completely different structure of internal pores.

Comparative analysis by key parameters is presented in the table:

There is an opinion about the difference in the geometry of the blocks, which is not always true. More often than not, materials made in different ways are compared. So, if we compare the foam blocks produced by the cassette method (molded) with cut gas blocks, then the former will be inferior in dimensional accuracy. The cassette method is common in small handicraft factories. In large-scale production, high technologies are used to maintain the accuracy of parameters, regardless of the type of material.

There are no differences in environmental safety. The basis uses natural materials, and chemical reagents either decompose during the reaction or become non-toxic.

2. What are the sizes of foam concrete and aerated concrete blocks?

The construction of walls and internal partitions from blocks is accelerated, in part, due to the relatively large size of the building material unit. The increase in geometric parameters, relative to the classic brick, became possible due to a decrease in the weight of the porous material. But even here there are limits regulated by GOST: the maximum size of one foam block in mm is 625x500x500.

Foam concrete blocks with a length of 600 mm, a height of 200 and 300 mm, a thickness of 100 (for partitions), 200 and 300 mm are in demand on the market. The exact dimensions are specified in GOST. Enterprises that produce cut blocks have the opportunity to fulfill orders with individual requirements for dimensions.

Gas blocks are in demand in the following sizes: length 600 or 625 mm, height 200 or 250 mm, thickness 100, 150, 200, 250, 300, 350 and 400 mm.

In the cheap production of blocks, the cassette method is used, in which the concrete mixture is poured into a mold with partitions. With this method, the deviation in size can be up to 5 mm.

When choosing a suitable option, the height and length are compared with the perimeter of the wall being erected for ease of masonry, and the thickness directly depends on the load and the required level of thermal insulation.

3. How much do foam blocks and gas blocks cost?

The cost of building materials is an important argument in favor of one or another type. Especially when it comes to similar technical characteristics. But you need to understand what to compare. There will be a strong bias in prices when comparing products of different quality. Foam blocks of handicraft production using outdated technology will be noticeably cheaper than gas blocks from a plant with advanced equipment. But this approach will not be useful, since saving means losing quality.

Let's analyze the price of certified products from large manufacturers with a good reputation. The price of blocks depends on the brand of strength and size.

In Moscow and the Moscow region, the cost of one wall foam block of the D600 brand and 600x300x200 in size from different manufacturers ranges from 100-115 to 160 rubles. At the same time, 1 m 3 costs 2900-3750 rubles.

The price of heat-insulating and structural aerated concrete wall blocks of the D500 brand and 600x300x200 in size in Moscow and the region starts from 110-112 rubles. per piece, and the upper limit is at around 167-175 rubles. per piece 1 m 3 contains 27.8 blocks, respectively, the average price of 1 m 3 gas blocks is 3058-3700 rubles.

The price of blocks in remote regions (Siberia, the Far East), as well as other building materials, will be on average 1.5 times higher than in the Central region. In addition, during construction, to increase thermal insulation, thicker walls must be laid.

The budget also needs to include the cost of paying for masonry services. On average, 1 m 2 of a wall of cellular blocks costs 1500-1700 rubles. The price list of contractors indicates the cost per cubic meter, which varies from 2400 to 4000 rubles.

4. Specifications: which is warmer and more durable?

Specific technical characteristics are available in the product card on the manufacturer's website or in the accompanying document for the supplied batch. The most significant indicators are strength and the ability to maintain a comfortable temperature for living.

The structure of blocks of different densities: structural and heat-insulating (D600) and heat-insulating (D300).

The thermal insulation of cellular concrete is due to the presence of a system of pores filled with air. According to this indicator, foam blocks with closed pores win. But if we consider a cheap option with poor geometry, requiring laying on cement mortar, then because of the “cold bridges”, the foam concrete wall needs additional insulation.

Aerated concrete blocks often have exact dimensions and are laid on an adhesive composition, so the finished aerated concrete box creates a better microclimate (keeps warm in winter and cool in summer). If we compare walls made of foam block and gas block on glue, then in the first case, thermal insulation will be better.

The strength of the material depends on the density, while the density has a negative effect on thermal insulation (the higher the density, the higher the thermal conductivity). Based on the density kg / m3, the blocks are divided according to their purpose: heat-insulating D300, D400, D500; structural and heat-insulating D600, D700, D800 and structural grades D900 and higher.

When comparing aerated concrete and foam concrete of the same strength grade, the first density will be lower. Autoclave production technology ensures the output of high strength blocks.

In relation to moisture, gas blocks with open pores and a rough surface are comparable to a sponge. In areas with frequent floods, aerated concrete houses are impractical and short-lived. Foam blocks are more resistant to the environment and absorb water more slowly when immersed in it. Water absorption in foam concrete is half that of aerated concrete. However, the porous structure of the material, one way or another, requires moisture protection.

5. What are the main pros and cons of foam blocks and gas blocks?

The general pros and cons of wall blocks and specific ones, peculiar only to a particular type, are presented in the table below.

You can also find other comments on materials on the forums, but most of them are related to the manufacturer’s dishonesty or violations of construction technology.

6. What to put foam blocks and gas blocks on: glue or cement mortar?

Manufacturers of gas blocks indicate the accuracy of the dimensions of the block as an advantage of their products, which allows them to be carried out. This method makes it possible to achieve a minimum joint thickness of 2-3 mm and high masonry strength. At the same time, the laying of gas blocks on cement mortar is not allowed, since the material takes a large amount of water, as a result, the laying is fragile. The adhesive for cellular blocks contains water-retaining additives and substances that increase the adhesion of materials.

The exception is the laying of the first row. It is carried out on a cement-sand mortar of 10-15 mm in order to compensate for the unevenness of the foundation and accurately level the blocks.

For foam blocks, laying is possible both on mortar and on glue. The first option is considered budgetary and is used for low quality material with poor geometry. The second one is used for high-quality certified blocks of high accuracy.

7. What kind of foundation is needed for a house made of foam blocks or gas blocks?

In promotional materials, you can find the statement that, due to the low weight of the blocks, the foundation can be lightweight and low-cost. But this gross misunderstanding can lead to irreversible consequences. Porous blocks are fragile and have low resistance to deformation, so they need a reliable monolithic foundation. But this option will not be cheap, and high costs will not always be rational.

To choose the best option for reliability and price, the following factors are taken into account:

• soil properties (groundwater level, freezing depth, heaving, soil type);
• the number of floors in the plan (direct relationship with the load on the foundation);
• the volume and complexity of the work (in some cases, an initially simple and cheap option can end up costing more than a monolithic slab).

Before starting work, they collect complete information about the characteristics of the soil on the building site. Errors in laying the foundation will soon be reflected in large cracks on the walls.

Most often, a strip foundation and a monolithic reinforced concrete slab are used, less often a pile-screw foundation.

8. How many blocks are needed to build a house: calculation method

The correct calculation of the required number of blocks for the construction of a residential building will save you from cost overruns: for extra volume or for a second delivery when reordering.

The calculation method for a one-story house is as follows:

• calculate the perimeter of the outer walls (the sum of the lengths of all sides);
• calculate the area of ​​\u200b\u200bthe walls (multiply the perimeter by the height of the floor);
• subtract the area of ​​window openings and doors;
• determine the volume of masonry (multiply the resulting area by the thickness of the walls);
• calculate the quantity in pieces by dividing the volume of masonry by the volume of one block (obtained by multiplying the length, height and thickness);
• multiply the resulting number by a loss factor of 1.05;
• similarly, we calculate the area of ​​internal load-bearing walls and partitions.

Read more about the nuances of the calculation with analysis on real examples.

9. Is it necessary to insulate, reinforce or plaster blocks of foam concrete and aerated concrete?

Despite good thermal insulation performance, porous blocks need external insulation. This is done to shift the dew point to prevent condensation from forming inside the unit. Insulation is also needed in areas with a temperate climate, when laying in two rows is impractical.

In most cases, it is necessary to fill in under the Mauerlat and under the floors with 2-3-story construction, small one-story houses and outbuildings are erected without reinforcement.

To protect against atmospheric precipitation (rain, snow and fog), the cellular material is covered with plaster. Plastering gas blocks is best done immediately on a reinforcing mesh, as there are reviews about the problems of its application. Foam blocks are also plastered to improve aesthetic qualities.

10. What is better foam blocks or gas blocks: popular opinion

On construction forums, these materials have their fans and opponents. The negative is more often associated with the purchase of cheap low-quality material produced using artisanal technology (cast (cassette) foam block and non-autoclaved gas block). Experienced builders are advised to purchase certified material from large manufacturers and follow the technology.

Aerated blocks of many are alarmed by the presence of aluminum powder in the composition, so they are considered ideal for non-residential outbuildings. Due to the high hygroscopicity, gas blocks are not suitable for internal partitions of the bathroom, shower room and bathroom. For the same reason, they are not chosen for the construction of a bath.

For a private house, the most successful option is the combination of gas blocks and foam blocks. The first go to the outer walls, and the second - to the construction of interior partitions.

Which is better: foam or aerated concrete?

In recent years, non-traditional building materials such as gas and foam concrete, or, as they are also called, porous blocks, have become widespread. These are two types of concrete blocks with a cellular structure.

Cellular concrete, due to its pores, has high thermal insulation properties.

The cellular structure of these types of concrete is characterized by high energy-saving qualities. In addition, ease of manufacture and use in construction, relative cheapness in comparison with brick and reinforced concrete brings gas and foam concrete to the forefront of their use in private construction.

Foam and aerated concrete, for all their similarities, have some differences.

Types of concrete

Aerated concrete is an artificial stone, which is based on a mineral binder and a silica component with pores distributed throughout the material.

The main components of cellular concrete are cement, lime, sand, water and foaming agents.

The binder may be cement, gypsum, lime, or compositions of these materials. Ground or unground sand or TPP ash is used as a dispersed filler.

They differ in manufacturing technology. Pores in foam concrete are formed when foaming agents are introduced, and in aerated concrete, porization is carried out due to hydrogen, which is released as a result of the reaction between metallic aluminum and alkali.

In the manufacture of porosity is relatively easy to regulate and this allows you to get concrete mixes of different density and purpose.

Concrete density is divided into three groups:

The scope of blocks from cellular concrete is defined by their density (D).

• a group of heat-insulating concretes, the density of which in dried form is 200-500 kg / m³, is used as a heater for floors, walls, roofs;
• a group of structural and heat-insulating concretes with a density of 500-900 kg / m³, used in the construction of enclosing structures and buildings up to three floors high;
• a group of structural concretes with a density of 900-1200 kg/m³, which are used in the production of reinforced concrete.

Materials used in the production of cellular concrete:

• astringent components and additives to them;
• silica component and additives;
• additives that form .

As the main binder in the production of gas and foam concrete with a cellular structure, it is recommended to use low-aluminate Portland cement grade 400 and higher.

Calcium quicklime is used for the production of mortars and concretes.

In the production of foam silicate concrete, cements with short setting times are used. The end of setting should be no later than 4-5 hours after pouring.

In the preparation of silicate cellular foam and aerated concrete, calcium quicklime is used. If the quality of the cement used in the production of cellular concrete is low, caustic soda NAOH is added to the aerated concrete.

With an increased concentration of chromium in cement, an aqueous solution of iron sulphate is added to the gas-concrete mixture.

The quality of cellular concrete significantly depends on the type of finely ground silica component, which is used as sand, TEC fly ash, and on heat treatment conditions.

The use of finely ground sand makes it possible to reduce the consumption of a binder foam and gas former, but this process requires additional equipment. The fineness of grinding is regulated by regulatory documents and depends on the size of the products.

Aluminum powder is small silver-gray lamellar particles that are used in the manufacture of cellular concrete.

As an additive that provides porosity to aerated concrete, aluminum powder and perhydrol are used. Currently, aluminum powder is introduced into aerated concrete in the form of a water-aluminum suspension, which provides a much better uniform distribution of the gas generator than the introduction of dry calcined aluminum powder into the mixture. To obtain a water-aluminum suspension, surfactants are used that facilitate the mixing of the components: rosin soap, creosote soap or sulfite-alcohol stillage.

The use of perhydrol also involves the use of catalysts or inhibitors. Chlorine is used as a catalyst, and salts of phosphoric acid are used as an inhibitor.

Foam concrete has several foam formers, which are formed from the following materials:

• glue-rosin - glue, rosin, caustic soda;
• aluminosulfonaphthene - kerosene contact, alumina sulfate, caustic soda;
• emolo-saponin - soap root and water.

The foaming agent is prepared in an emulsifier equipped with rotating blades.

Autoclave production method

Aerated concrete combines the best properties of building materials made of stone and wood.

Aerated concrete, like foam concrete, is an artificial porous stone with first-class thermal insulation and energy-saving properties, and low weight.

It is made from a mixture of Portland cement, a silica component and a blowing agent. According to the chemical reactions caused, gas generators are divided into the following types:

• substances that react with the binder component - aluminum powder;
• substances that decompose with the release of gas - perhydrol;
• substances that enter into exchange reactions with each other. As a result of these reactions, a large amount of gas is released - ground limestone and hydrochloric acid.

Gas blocks are easy to process: they can be cut, sawn, drilled and milled with both electric and hand tools.

A standard gas block weighing 30 kg replaces 30 bricks. And the light weight of the blocks allows construction without the use of special lifts, which reduces the cash costs for renting equipment. Aerated concrete blocks are easy to cut and process.

To obtain aerated concrete mix, use:

• water;
• lime;
• cement;
• quartz sand.

The production of cellular concrete is carried out on semi-automatic or fully automated production lines, the cutting of blocks is carried out using wire strings.

The production of aerated concrete in industrial conditions is carried out from Portland cement, lime and sand with the addition of aluminum powder by the autoclave method.

The casting technology for the production of gas-cell concrete provides for pouring the finished cellular mixture into block molds.

The starting materials are dosed and fed into a self-propelled mixer, in which the mixture is mixed for 4-5 minutes. An aqueous suspension of aluminum powder is added, and after thorough mixing, the mixture with aluminum powder is poured into metal molds not to the very top. Leaves space to fill the form to the top after swelling.

Heat treatment of aerated concrete is carried out in autoclaves with saturated steam.

The technological process of production includes the following operations:

• mixing the solution in a concrete mixer;
• pouring the solution into molds;
• swelling of concrete in molds under the action of a chemical reaction;
• removal of "pink salmon" with a string;
• autoclaving to obtain a building material with a set of predetermined properties and characteristics.

non-autoclave method

Foam concrete blocks continue to gain strength over time.

Foam concrete is produced using several technologies. The most widespread is the production of foam concrete in a steam generator and in cavitation plants.

Foam concrete is obtained from a mixture consisting of cement, sand or fly ash, water and foam. Foam is formed in the foam generator from a solution of a foaming agent and water. Changing the ratio of components in the mixture, the use of different cooking technologies allow you to control the ratio of solid and air phases in the mixture. As a result, it is possible to obtain foam concrete of all three groups: structural, structural and heat-insulating, heat-insulating.

In cavitation plants, the mixing of raw materials is carried out in a pressure mixer, without the use of a foam generator, which makes it possible to produce foam concrete in small volumes.

Has a wide range of applications. They build from it:

Foam concrete is made from sand, cement, water and special foam by a mechanical method.

• bearing walls in private construction;
• external enclosing structures in the construction of high-rise monolithic buildings;
• internal partitions;
• thermal insulation of pipelines;
• thermal insulation of technological equipment;
• sound insulation of floors;
• for roof insulation;
• to fill voids for various purposes;
• for the manufacture of building blocks, fences and balcony railings;
• for the manufacture of wall panels, ceilings, various partitions.

Foam concrete has the following advantages: environmental friendliness, durability, absorbs a small amount of moisture, fire safety, and provides good sound insulation.

The production of foam blocks is carried out in three ways:

1. in cassette metal molds.
2. Cutting foam concrete arrays on cutting machines.
3. Pouring the foam concrete mixture into special molds followed by automatic stripping.

Comparison of types of cellular concrete

Aerated concrete differs in production technology: aerated concrete is autoclaved, and foam concrete is a non-autoclave or mechanical production method.

1. Density and strength. Aerated and foam concrete have the same density, and in terms of strength, the indicators are better for aerated concrete.
2. In terms of frost resistance and thermal conductivity, both materials have similar characteristics.
3. The water absorption capacity of aerated concrete is higher, but it does not affect the quality of the material in construction.
4. Cost of materials. This indicator is better for foam concrete, its cost is 20-25% lower than. This is achieved by the low cost of foaming additives.
5. The cost of production equipment. Equipment for the production of cellular gas and foam concrete has a high cost, but the cost of equipment for gas concrete is an order of magnitude higher than the cost of foam concrete.
6. The production of foam blocks can be arranged at the construction site.
7. The closed cell structure of foam concrete allows it to be used for construction in areas of potential flooding by flood waters.
8. The geometry and structure of the blocks is better for gas-cell concretes.
9. The properties of gas silicate to absorb and release water are comparable to those of natural wood.
10. Gradual construction of structures according to specially developed projects. This indicator characterizes aerated concrete better. It allows you to easily build on and complete the house at any time.
11. Aerated concrete requires plastering work, and these works are not required for foam concrete.

The popularity of cellular concrete in the form of blocks is growing from year to year. Foam and aerated concrete are valued for their high technical characteristics. In recent years, other products made of cellular concrete have also been in demand: lintels, floor slabs, stair steps.

Didn't find the answer in the article? More information

Modern technologies for the construction of country houses widely use blocks of foamed concrete. They are light, strong and large in size, which allows you to build walls quickly. But it is not always clear what is better to choose - foam concrete or aerated concrete. And is there a difference between them?

There is a difference and it is in the method of obtaining the material. Foam concrete and aerated concrete are related materials, both of them are lightweight concretes with small air bubbles inside. In fact, it is foamed and frozen concrete in this state. But the way these bubbles form is different.

Why is concrete foamed?

As you know, the best heat insulator is air. The most effective thermal insulation materials are those that contain a large amount of air pores inside. But the more voids inside, the less durable such material. Foamed cellular concrete successfully combines the strength of concrete and good heat-insulating properties of air.

Production features

foam concrete made from a cement-sand mixture with the addition of a chemical reagent - a foaming agent. Foaming agent for foam concrete can be of synthetic and organic origin. The mixture is thoroughly mixed and poured into molds. Hardening occurs naturally, which makes it possible to produce foam concrete blocks for small enterprises.

aerated concrete or autoclaved foam concrete is made only in the factory. It does not contain any chemical additives for foaming, it consists entirely of mineral raw materials: sand, lime, cement, gypsum, water and aluminum powder as a blowing agent. As a result of a chemical reaction, bubbles form, and they form pores. Hardens the material at high temperature in a pressurized autoclave.

What are good houses made of foam concrete and aerated concrete blocks?

Both foam concrete and aerated concrete are durable building materials, they do not burn, are not environmentally harmful, durable and, at the same time, are easily processed. Houses made from these materials are much cheaper than those made from traditional bricks. There are several reasons:

• The low cost of the blocks themselves.
• Savings on heat and sound insulation. The low thermal conductivity of materials allows you to build walls of reduced thickness, the house will still be warm.
• Large block sizes allow you to spend less connecting material (cement or glue) and build faster.
• Both aerated concrete and foam concrete are lightweight materials; building a house does not require the construction of a massive foundation.

Comparative characteristics of foam and aerated concrete

The advantages and disadvantages of these building materials are about the same. The advantages include the following features:

• High strength.
• Ease.
• Ease of handling and use.
• Good heat-insulating and sound-proofing properties.
• Does not rot, is not damaged by rodents.

Disadvantages of materials:

Compared to ordinary concrete, both aerated concrete and foam concrete withstand less mechanical stress.

How to distinguish aerated concrete from foam concrete

Differences between the foam block and the gas block are clearly visible:

• Foam block: gray shade, smooth surface.
• Gas-block: color - white, surface rough, embossed.

If you break off a piece, then the pores of foam concrete are much larger. After placing pieces of both materials in water, after a while you will notice that the open-pore aerated concrete will quickly absorb moisture and sink to the bottom, the foam concrete will remain on the surface for several days.

Strength

They are produced in various densities depending on the purpose of the materials. At the same density, foam concrete loses a little to autoclaved aerated concrete in terms of strength. Aerated concrete is stronger. In addition, the quality of aerated concrete is controlled by a large manufacturer, and in the production of foam concrete at small enterprises, it is difficult to control its strength. Its strength depends on the quality of the foaming agent. It is no secret that manufacturers can use low-quality, cheap blowing agents to reduce the cost of blocks.

The strength is also affected by the factor that the structure of aerated concrete is more uniform. In foam concrete, there may be larger and smaller pores, which affects the strength indicators.

Ability to retain heat

The denser the structure of the concrete block, the worse it holds heat. Therefore, foam concrete, which has a low density, will be a better heat insulator than aerated concrete.

Exact block sizes

The accuracy of the geometric dimensions of blocks made of autoclaved aerated concrete is greater. It is regulated by GOST, the permissible deviations are up to 3 mm in length, up to 2 mm in width, and up to 1 mm in thickness, while for foam blocks, deviations in geometric dimensions in thickness can reach 5 mm.

This is due to the fact that when pouring molds for foam blocks, there are always deviations in size. Gas blocks are cut after hardening with a special string and their dimensions are more accurate.

At first glance, 5 mm is small relative to the total block size. But the violation of the geometric dimensions of foam concrete blocks leads to deterioration of the masonry and a greater consumption of masonry materials.

Environmental friendliness

Autoclaved aerated concrete is an absolutely environmentally friendly material. During its production, a reaction occurs between lime and aluminum. The hydrogen released as a result is not all released during the solidification of the material, but it is not a poisonous gas. Aerated concrete is made from mineral raw materials, therefore it is completely not subject to decay, and due to the ability to regulate the humidity of the air in the room, the likelihood of fungi and mold on it is completely excluded.

Foam concrete is also a safe building material. It is made from cement, sand, ash, crushed stone production waste, and chemical additives are used as foaming agents. Foaming agents forming foam concrete, both proteinaceous and artificial, do not contain harmful substances. The quality and environmental friendliness of such additives cannot always be strictly controlled. This fact is used by large enterprises for the production of aerated concrete to promote their product in the construction market. But even if there is a possibility that the chemicals are not entirely safe, their concentration in the foam concrete itself is extremely low. In addition, the pores of foam concrete are closed and airtight.

Both building materials do not have significant environmental deficiencies and this parameter cannot be decisive when choosing.

Water absorption

Both foam concrete and aerated concrete have a porous structure, which means that they absorb moisture to one degree or another.

Aerated concrete absorbs more moisture than foam concrete. This is due to the fact that in foam concrete the pores are of a closed type, and in aerated concrete there are pores of both open and closed types. Aerated concrete wall must be covered with a protective layer, otherwise it will pick up a lot of moisture. During frosts, wet aerated concrete does not behave in the best way - it cracks. As a coating, plaster or tiled lining is used.

Foam concrete can also be used without a waterproof coating, but usually the walls are finished, leveling them, as well as for decorative purposes.

Price

Foam concrete is cheaper, the components for its manufacture are not very expensive, and the equipment is not complicated. The production of autoclaved aerated concrete is more expensive. But during the construction of foam concrete, more may be needed than aerated concrete due to the fact that it is less durable.

It is also important that aerated concrete is laid on an adhesive mixture, and inexpensive cement mortar is quite suitable for foam blocks. True, with glue, laying is faster, and it will take much less than a cement mixture.

Conclusions:

If you want to build a low building, block a wooden building, make an extension to a country house, then foam concrete would be the best choice.

If you need to build a large house with reliable load-bearing walls - use aerated concrete. But do not forget that you need to build quickly, you can not leave an unfinished house to get wet in the rain.

We hope that this comparison of the advantages and disadvantages of foam concrete or aerated concrete was timely and helped you. Good luck building!

Modern concrete materials with a porous structure are successfully used for the construction of a residential building, a dacha, a bathhouse, a garage and an outbuilding. They have high thermal insulation properties, low weight and ease of processing. At the planning stage of the future construction, each owner, analyzing the performance characteristics of the materials, tries to choose the option that is beneficial for himself.

So what is better to use for construction - aerated concrete or foam concrete? To do this, it is enough to compare the materials in order to determine the main similarities and differences between them.

Applications

Foam blocks and gas blocks are one of the most popular building materials with a lightweight cellular structure and excellent thermal insulation characteristics.

Foam concrete has a greater mass, long service life and high strength. This allows it to be successfully used for the construction of low-rise residential and commercial buildings, livestock facilities and outbuildings, the height of which does not exceed 3 full floors. They build from it:

• Bearing wall structures.
• Internal partitions.
• Technical barriers and fences.
• Reinforced floors.

Aerated concrete has a constant and uniform structure, resistant to shrinkage and cracking. These characteristics allow it to be used in the mass construction of industrial, commercial and domestic facilities of various types. Often it is used to build:

• Partitions.
• Bearing walls.
• spans of frame buildings.
• multi-storey complexes.

Features of the production of cellular blocks

The main difference between aerated concrete and foam concrete lies in the production technology, which allows the formation of an internal porous base of block materials.

Lightweight porous concrete is produced from environmentally friendly components. It is during the production of materials that their unique performance characteristics are formed.

Production of foam blocks

For the manufacture of foam blocks, a more simplified technology is used, which makes it possible to obtain a practical and safe material of high quality.

1. Dry components are mixed in a prepared container and diluted with a small amount of water.
2. A foaming agent is added to the resulting mixture. All components are subjected to mechanical mixing to obtain a homogeneous solution. In the process of kneading, the necessary chemical reactions occur with the release of free gases. The gas filler provides the necessary porosity of the material.
3. The finished solution is poured into special molds and left to fully harden for 5-10 hours. Products are removed from molds and stored to dry naturally in a well ventilated area protected from rain.
4. The technological strength of the finished blocks is achieved in 2-3 weeks after production.

A distinctive feature of the products are surface irregularities, significant deviations in the geometry of shapes and sizes.

Important! Monolithic formwork can be used as the basis for pouring the concrete mixture. After drying, the base is cut into separate blocks.

Production of gas blocks

Unlike foam concrete, aerated concrete blocks are produced under industrial conditions, which guarantees excellent quality and strength of the material.

Stages of the technological process:

1. Dry components in the required proportions are diluted with water and kneaded until a homogeneous solution is obtained. The duration of the batch is set by the technological map (TK).
2. The finished solution is poured into molds. In this case, aluminum powder or paste is used as a foaming agent, which enters into a chemical reaction with a liquid cement mortar. The evolution of hydrogen gases contributes to an increase in the total volume of the solution.
3. After complete hardening, the cement base is removed from the mold and cut into separate blanks in the form of blocks, slabs and panels.
4. At the final stage, finished products are subjected to heat treatment using autoclaves or electric furnaces. In autoclaves, the blocks are treated with hot steam at a pressure of 12 atmospheres, in electric ovens they are dried at high temperatures.

This production technology provides an almost perfect geometry and high strength of gas silicate.

In this regard, the gas block is more preferable than its direct counterpart, since the autoclave production technology provides excellent quality and good performance characteristics of the material. The production of foam concrete does not involve the use of expensive equipment, so the entire technological process can be organized at home.

Comparative characteristics of aerated concrete and foam concrete

Despite the fact that the production of cellular concrete blocks is strictly regulated by uniform state standards, the technical parameters of these materials have significant differences.

Components

Concrete materials are produced using the technology of mixing cement with fillers that provide it with a cellular structure.

Foam concrete is produced on the basis of the following components:

• Lime or sand of medium fraction is a mineral filler.
• Foaming agent - a chemical additive to create a porous structure.
• Water.

The composition of the gas block includes the following components:

• Portland cement is a binder.
• Quartz sand, gypsum, lime, wood ash, slag waste - mineral fillers.
• Aluminum paste or powder - a component for the formation of pores.
• Water.

Aluminum foaming agent is a harmful component in its pure form; in the production of aerated concrete mortar, it is completely dissolved in water.

Structure

The difference between aerated concrete and foam concrete blocks lies in their structure and appearance:

• Foam blocks: large closed cells with a low level of moisture absorption, excellent sound and heat insulation properties. They have a smooth gray surface.
• Gas blocks: small cells with microcracks formed as a result of gas formation. They are distinguished by good air and moisture permeability, insufficient thermal insulation and require mandatory external finishing. The material has a relief rough surface of white color.

Strength

Which material is more durable - aerated concrete or foam concrete? This parameter directly depends on the block density.

The density of aerated concrete blocks is from 200 to 600 kg/cu. m, the density of foam concrete blocks is from 300 to 1600 kg / cu. m.

Modern technologies make it possible to create gas silicate concrete with a density of up to 400 kg / cu. m, capable of withstanding the ultimate load, as well as a foam block with a density of over 600 kg / cu. m.

Despite the high density, foam concrete is definitely inferior to its competitor. This is due to the heterogeneity of the structure over the entire area of ​​the material.

Frost resistance

This parameter determines the ability of the cellular material to maintain its performance characteristics during repeated freezing and thawing cycles.

Compared to other porous materials, autoclaved aerated concrete blocks have increased frost resistance, low thermal conductivity and excellent vapor permeability.

For example, due to the special structure, the strong structural Sibit gas block is able to withstand 75 full cycles of freezing and thawing, while for a foam block this figure is only 35 cycles.

Important! When hydrophobic components are added to the feedstock, the frost resistance index of aerated concrete can be increased up to 75 cycles.

Features of use

Possessing a lot of advantages, porous foam concrete is widely used for low-rise construction. It is also suitable for the construction of monolithic buildings and structures. In this case, it is used as an insulating or additional material.

Aerated concrete blocks are used as the main structural and heat-insulating material for the construction of objects of varying complexity. The blocks are suitable for arranging heat-resistant and other partitions, filling frame structures made of metal and concrete, restoring dilapidated buildings and erecting half-timbered structures of residential buildings. Moreover, they can be operated in any climatic conditions.

Price

What is the main difference between foam concrete and aerated concrete? in their market value. With equal technical parameters and dimensions, gas silicate will cost more than foam concrete blocks. This is due to the complexity of the technological process, the high cost of equipment and consumables, as well as significant costs for its transportation.

Foam blocks are produced on cheaper and simpler units that can be located on the construction site.

The market value of aerated concrete blocks is higher, but the production costs are offset by the quality of construction. At the same time, it is economically profitable to build a warm house from aerated concrete due to the lower consumption of building material. In addition, the lining of aerated concrete will take less cement mortar than it will take to level the foam concrete blocks.

Table of technical parameters of foam concrete and aerated concrete

The final comparative table shows the main technical parameters that determine the performance properties of aerated concrete and foam concrete. Such a comparison will determine which of the materials should be chosen for the construction of residential buildings and other objects.

It is difficult to give an unambiguous answer to the question of which material is the best - foam concrete or aerated concrete. Each of the materials has its own distinctive advantages and disadvantages. Based on the presented table, a brief conclusion can be drawn: gas blocks have higher rates of frost resistance and strength, and foam blocks - thermal conductivity and environmental friendliness. Which technical parameter is more important depends on the scope and characteristics of the application of the building material.