home · Tool · What to add to the solution in winter. Proper bricklaying in winter: a technology that must be followed. Pouring concrete in winter - the advantages of winter concreting

What to add to the solution in winter. Proper bricklaying in winter: a technology that must be followed. Pouring concrete in winter - the advantages of winter concreting


Winter masonry

Construction using so-called “wet” processes is traditionally carried out in warm time of the year. But what should builders do in winter? Shouldn't we go into hibernation? And developers are not particularly happy about downtime. Technologies are coming to the rescue today, allowing construction to continue despite the cold.

However, winter also has some advantages. For example, the soil becomes hard and heavy special equipment can move freely on it. In addition, construction materials and the services of construction crews are becoming cheaper. In a word, building in winter is possible! And building regulations do not prohibit this.

The first thing that frost affects during construction is the hardening of mortars, which becomes impossible after crossing the 0°C mark. Free particles of water freeze and stop interacting with other chemicals. building mixtures. As a result, the cement hydration reaction does not occur, and the solution does not gain the required strength. Moreover, frozen water destroys the already weakened structure.

Therefore in winter time masonry of brick, cellular concrete blocks, rubble stone, as well as monolithic structures performed using antifreeze additives, which are purchased separately or are present in ready-made “winter” formulations.

Antifreeze additives for mortars

When low temperature interferes with the use of water in its liquid state, then one solution to the problem is the use of salts, which lower the point at which water turns into ice. As we know, utility workers sprinkle regular salt roads so that they don't freeze. Kitchen salt is not suitable for mortars; special compounds are required, which are sold in cans.

When independently preparing “winter” mortars, antifreeze additives are introduced directly on the construction site and taking into account the temperature environment.

The main salts present in antifreeze additives are sodium nitrate and sodium formate. Compositions based on such salts are usually used in construction at temperatures down to -15°C. If it is colder outside, down to -30°, then potash is used.

The advantage of all of the above antifreeze additives, in addition to their direct effect, is also the absence of a corrosive effect on the reinforcement laid during the construction of the building. However, this cannot be said about chlorine-containing preparations, which, on the contrary, accelerate corrosion processes.

It is important to know that potash and sodium nitrate are toxic substances. The solution itself with such additives is not dangerous after drying, but caution must be exercised when working with it. It is necessary to prepare solutions wearing goggles, gloves, a respirator and rubber boots - this is required by safety regulations. These substances should be stored in their original packaging in a dry, locked room. But sodium formate is not a toxic substance, so it is easier to work with.

To obtain a solution with the required properties, it is very important to strictly adhere to the manufacturer’s recommendations regarding proportions, which in turn depend on the ambient temperature. The table shows only average proportions as percentages.

Adapt mortars Not only antifreezes help with use in cold weather, but also plasticizers (superplasticizers), which by increasing the plasticity of the mass make it possible to reduce the water content. These additives increase the frost resistance of the solution and increase its density. After laying in the solution for several days, no physical changes occur, due to which it has time to set.

The presence of plastifiers in solutions is desirable when doing masonry, concreting and installing self-leveling floors. Plasticizers are introduced along with water. Usually their content depends on the weight of cement, and amounts to 5-10% of it. This is what concerns masonry mortars, and for concreting, the plasticizer content increases to 10-15% of the weight of cement. This achieves sufficient plasticity necessary for laying, and also increases the moisture resistance of concrete structures.

Special additives used in winter construction include so-called mortar hardening accelerators. Such compositions allow the mortar (concrete) to gain strength before it freezes. Their area of ​​application is primarily technology permanent formwork, creation of concrete floors and other monolithic structures. The content of accelerators is usually in the range of 2-5% by weight of cement.

To obtain maximum effect, it is advisable to use a complex of additives. This recommendation does not apply plaster solutions, in which only antifreeze is added. Plasticizers are absolutely contraindicated for them, since the plaster will not stick, but will flow down.

Antifreeze additives and plasticizers are simultaneously added to masonry mortars. When concreting, it is advisable to introduce hardening accelerators into the concrete composition in combination with plasticizers or to combine three types of additives at once. When creating additive complexes yourself, you should take into account their possible incompatibility. The manufacturer indicates compatibility information on the packaging. There are also ready-made additive complexes with certain properties.

Ready-made dry mixes for winter construction

In addition to anti-frost additives, you can also find ready-made dry mixtures containing one or more additives. Such mixtures are used for masonry and finishing. Masonry mixtures are divided into light (up to 1500 kg/m³) and heavy (from 1500 kg/m³). They can be either cement or cement-lime. Heavy mortars are most often used for masonry.

The advantage of ready-made mixtures is their impeccable proportions and ease of use. And although it is not difficult to prepare the mixture yourself, there is still a risk of making a mistake, for example in the compatibility of additives.

Ready mortar mixtures allow brick or block masonry to gain up to 80% strength over the winter, which practically corresponds to the behavior of summer masonry. By the way, aerated concrete blocks can also be laid on proprietary solutions recommended by material manufacturers.

Naturally, you will have to pay for the convenience of using ready-made mixtures. Solutions made from them are significantly more expensive than those prepared independently using additives from canisters. However, ready-made mixtures contain adjusted proportions and save time during preparation. They are mixed with warm (30-40°C) water and mixed with a drill with a mixing attachment. The resulting solution must be used within one hour from the moment of preparation. In this case, you need to ensure that the temperature of the solution in the container does not fall below 0°C. If the mixture is allowed to freeze, it can no longer be reheated, which means it will have to be thrown away.

Winter masonry

It is very important that during winter laying, construction material was absolutely clear of snow, ice and frost. The masonry must be carried out quickly, and the mortar must be prepared just enough so that it has time to be produced before. To do this, it is placed in insulated containers. But even if the solution is slightly frozen, it cannot be warmed up. A heated solution will no longer be so strong.

During breaks from work finished part masonry should be covered with film or roofing felt. Otherwise, when resuming work, you will have to clear the stone of ice, snow or frost.

At negative temperatures The solution should be prepared in a heated room. When independently preparing masonry mortars, use cement grade M50 and higher. It is also important to ensure that there is no ice in the sand, even small particles.

The thickness of masonry joints during winter construction is 1-3 mm. Thicker joints can cause significant settlement of the masonry in the spring. The verticality of the walls must be checked with special care, since a wall even with a slight deviation can “move apart” during a thaw.

The masonry must be laid evenly around the entire perimeter. The walls and pillars around the windows are reinforced with metal mesh.

With the arrival of spring, the masonry thaws and at this time precipitation phenomena are possible. It is necessary to check the verticality of the walls every other day, and if a tilt is detected, then immediately install strong supports that can prevent further movement. As a rule, the southern walls are at risk, so they need to be controlled first.

When the positive temperature lasts 10 days, the supports can be removed. By the way, some builders pre-install supports during winter masonry, and in early spring they artificially thaw the masonry by installing air heaters indoors. The temperature is raised to 30°C and maintained for several days in a row. The method is very expensive, but, nevertheless, is sometimes used.

There is an opinion that winter period- Not good time for construction, and it is true. Winter conditions dictate a number of restrictions. It is necessary to install heating for the construction site and cabins for employees and workers, and to clear the snow from the access road. Due to the short daylight hours, the construction period is increasing.

Still, it is possible to build a house in winter. The regulations do not prohibit this either. The cost of services for construction crews and the price of building materials in cold weather are also reduced.

In the cold months, walls are laid from such wall materials like shell rock, brick, rubble stone, gas, ceramic and foam blocks, erect walls monolithic walls made of concrete. You can also use the permanent formwork method and perform plastering work.

But there is a problem. The water used for mixing construction mixtures freezes and does not interact with other chemicals.

Therefore, if the temperature drops below 0°C, the hardening of the finished solution ends. And the ice formed significantly destroys the structure of the solution, significantly reducing its strength.

To do this, in the winter season it is necessary to add antifreeze additives to construction mixtures or buy ready-made “winter” compositions.

We use antifreeze additives

The problem of solutions being ready for use in frosty weather is solved in several ways. But most often, antifreeze additives are added to construction mixtures - special salts that reduce the freezing point of water and prevent it from turning into ice. This is done directly on the construction site. As a result, the mortar joint has time to gain sufficient strength before the water freezes. For this purpose, additives such as potassium carbonate (potash), sodium nitrate (sodium nitrite), calcium chloride, sodium chloride, sodium formate, etc. are used.

When building a cottage for work at temperatures down to -15 ° C, experts advise choosing sodium nitrite or sodium formate as an additive. If it gets even colder, you need to use potash (up to -30 ° C). The advantage of all options is the absence of corrosion during the construction of reinforced structures. Efflorescence does not appear on the surface of the hardened solution. But it is better not to use chlorine-containing substances - they accelerate corrosion processes, which leads to the destruction of reinforcing parts.

It is true that potash and sodium nitrite are dangerous and poisonous materials. Final cement or concrete solutions do not harm human health, but when using these additives you must follow safety precautions: store the substances in a dry and locked room in the original packaging, and prepare solutions wearing goggles, rubber gloves, boots and overalls. Sodium formate is easier to work with because it is not toxic.

In addition to antifreeze additives (relatively speaking, “antifreeze”), there are plasticizers (or superplasticizers). They increase the plasticity of the mortar mixture and thereby make it possible to reduce the amount of water required for mixing. Plasticizers improve the frost resistance of the solution and increase its density. In this regard, for at least several days after installation, no physical changes occur in the solution, and it has time to set.

The use of these additives is useful in the manufacture of mortars for masonry, concrete work, and installation of self-leveling floors. Plasticizing substances are introduced along with water; their minimum amount should be 5-10% of the weight of cement. This proportion is sufficient for masonry. If concreting is necessary, you need to increase the plasticizer consumption to 10-15%. This will further increase the plasticity of the mixture during laying and at the same time the moisture resistance of the finished concrete.

Finally, there are winter additives such as special compounds that accelerate the hardening process of the solution (strength gain). Thanks to them, it turns into a strong stone before it has time to freeze. Such additives are useful, first of all, for creating monolithic structures (concrete floors, walls using permanent formwork technology). Their consumption is usually 2-5% by weight of cement.

But it is most optimal to use two or more types of additives at the same time. The exception is plaster mixtures. It is better to introduce only “antifreeze” into them. And plasticizers for such compositions are completely contraindicated, otherwise they will simply flow down the wall after application, without having time to set properly.
But it is better to add anti-frost additives and plasticizers at the same time to the mortar for laying walls made of bricks or large blocks. Hardening accelerators in combination with plasticizers are useful for concrete. You can combine all three types of additives. In this case, it is necessary to take into account the fundamental possibility of their sharing without loss of quality. Information about this can be found in the manufacturer's instructions.

There are also ready-made combination supplements on sale that combine two or more qualities.

Concreting in winter

Conduct concrete works in winter (for example, build walls using the method concrete formwork or fill monolithic ceiling) experts recommend at an air temperature of at least -10 “C. With more severe frosts It is better to temporarily stop concreting. The “fresh” structure must be covered with roofing felt, plastic film or mineral wool for several days until the concrete sets securely.

A concrete mixer is suitable if there are a lot of workers or the finished solution can be stored in a heated room

Otherwise, the mixture should be prepared in small portions

Ready-made antifreeze compounds

In addition to combined additives, manufacturers also offer ready-made dry mixtures, to which certain antifreeze additives have already been added at the factory. They come in two types: masonry and finishing. The former, in turn, are divided into heavy (with a density of more than 1500 kg/m3) and light (density, respectively, less than 1500 kg/m3). There are both simple mortars (cement or lime based) and complex ones (cement-lime) on sale. Cement or cement-lime heavy mortars are used for masonry.

Using ready-made mortars, of course, is much more convenient than preparing the batch yourself: there is no need to carefully control the quantity, take into account the compatibility of materials, etc. Laying bricks and blocks on ready-made mortar mixtures allows the wall to gain up to 8% of the required strength over the winter, which is comparable to the results of summer masonry. By the way, there are also “branded” dry mixes. For example, many manufacturers of aerated concrete blocks offer their compositions.

But you have to pay for convenience - such solutions are significantly more expensive than conventional ones. But they contain chemical substances in repeatedly adjusted proportions, and all that is required is simply to dilute them clean water(preheated to 30-40 °C) and mix (using a drill with a mixer). The finished solution should be moderately plastic, should not spread and be too thick. The mixture must be used within an hour of preparation. Moreover, you should ensure that the temperature of the solution itself does not fall below zero. The frozen mixture will have to be thrown away: experts categorically do not recommend using a heated solution (such advice can be found).

Winter laying conditions

The first condition when constructing walls in cold period— before laying, a brick or block must be cleared of snow, ice or frost. Second important rule— cement and the finished mixture should be stored in insulated containers. Moreover, it is impossible to warm up a slightly set solution. Therefore it is very important to ensure high speed masonry and rapid compaction of the underlying rows with the upper ones. And during breaks, it is advisable to cover the finished part of the wall with plywood, roofing felt or film. Or thoroughly clean the surface of snow and frost when resuming work.

The solution is prepared at subzero temperatures in heated rooms, using cement grade M50 or more. Large lumps (more than 1 cm) and pieces of ice are not allowed in the sand.

Masonry using winter solutions must be done with thin seams of the order of 1-3 mm (that is, the same as in summer time). This requirement is due to the fact that large seams increase the heat loss of the structure and can lead to significant settlement in the spring. Also, during work, you should carefully check the verticality of the walls: any deviations are also fraught with problems during a thaw. The laying is carried out evenly along the entire perimeter of the building or the length of the wall so that there are no large differences in height. The pillars and partitions between the window openings are reinforced with steel mesh.

Finally, in the spring, during the thawing period, it is necessary to monitor the strength and stability of the wall made in winter. Indeed, as the temperature rises, the masonry also thaws, and small sedimentary phenomena and microcracks may occur. Therefore, as during masonry, you should check the verticality of the structures every 2-3 days, and if a minimal deviation is detected, you should immediately install struts and supports from wooden logs or metal pipes, which will prevent further displacement. This is usually required for walls located on the south side. You can cover them during the thaw (for example, with glassine). After positive temperatures have been maintained around the clock for 7-10 days, the supporting elements are removed.

Another way to combat uneven settlement is the preliminary installation of supporting elements and forced thawing of the wall during early spring using air heaters, electric heaters or heat guns located inside the building. To do this, it is necessary to raise the room temperature to 30°C and maintain it for several days. However, this method is more labor-intensive and requires considerable energy consumption, a reliable connection to the power grid near the house, or the use of autonomous generators.

When laying in winter, it is especially important to maintain the thickness of the mortar and maintain the level

Failure to follow the rules for preparing mortars and masonry will, at a minimum, lead to the formation of efflorescence, and at a maximum, to the appearance of cracks

During breaks between work, you need to cover fresh masonry

Plastering work in the cold

Perform outdoor work in winter Finishing work Experts do not recommend it for a newly erected wall. It is better to postpone this process to the spring, and at a time when the constructed structure has completely thawed. At the same time, plastering finished facades built in summer or autumn (for example, from gas blocks or ceramic bricks), Can. But in the event that it is assumed facade insulation, work on its finishing, as well as applying the finishing plaster composition It’s better to postpone it until spring.

Before plastering, the surface must be thoroughly cleaned of dirt, snow, ice and frost. All layers of plaster should be applied within one day, applying the next one immediately after the previous one has thickened slightly.
The main thing is not to forget to add antifreeze additives to the composition. It is necessary to introduce “antifreeze” only if the outside air temperature drops below 5 °C. Under no circumstances should you use old, long-stored mixtures or formulations. After all, the result will be, as they say, obvious - in the form of efflorescence and smudges on the surface of the wall.

Not a single complex construction process can be completed without the use of cement - it is cement that acts as the main binding element in concrete, is used in masonry processes, and so on. If there is a need to use cement mortar in winter, then you need to know how to prepare it correctly and take into account the effect of negative temperatures on its quality.

What happens to cement mortar at sub-zero temperatures?

To know how he behaves cement mortar in frost, it is necessary to understand the processes occurring inside it. Thus, cement mortar hardens when the cement grains contained in it and water interact. The lower the temperature, the slower the hardening of the solution will be - and at 0°C this process stops completely.

When the temperature drops below 0, free water in the solution becomes ice, which will not interact with the binder components. After freezing, the hardening process stops - it will not begin as long as the solution is in a state of ice. In addition, the frozen water in the mixture increases significantly in volume - this leads to the destruction of the structure of the solution and a significant decrease in its strength - even if it managed to partially gain it before freezing.

To make quality cement mortar at sub-zero temperatures, you should adhere to these recommendations:

  • use heated water;
  • add to the solution only the sand that was stored indoors (if the material was stored outdoors, it will need to be preheated);
  • use antifreeze additives - special substances that prevent water from freezing.

The use of antifreeze additives requires strict adherence to all necessary recommendations manufacturer - according to the amount of the substance and the order of its addition.

Carrying out work with cement mortar in winter also requires a special approach - the resulting surface will need to be protected with slabs, straw mats or polyethylene insulation. In addition, it is important to reliably preserve concrete from icing. Do not forget that thin layer concrete is more susceptible to freezing than thick concrete, and therefore measures to protect it must be strengthened. It is also believed that all winter concreting work should be carried out during the day, when the temperature is maximum, and in the evening the created structure must be additionally insulated.

No construction can be done without the use of cement mortar. The strength and durability of the masonry directly depends on it, as the main binding material, so it is very important to know how to prepare it correctly.

This seemingly simple process has its own nuances: the correctly chosen brand of solution, the correctly selected proportions of the constituent materials, their appropriate quality, the sequence of making the solution, as well as the features of its preparation in the cold season at sub-zero temperatures.

First, let's look at the brands of solutions and the principle of their determination. Identifying the brand is quite simple. To do this, you need to divide the brand of cement used by the amount of sand. To make it clearer, let's give a few examples:

  • to obtain a mortar of grade 100, you need to take one bucket of grade 400 cement and four buckets of sand. The result will be a mortar in which the ratio of cement and sand is 1:4 (grade of cement 400: amount of sand 4 = grade of mortar 100). The solution is also added detergent about 50-100 g, which makes the solution more elastic;
  • to obtain a mortar of grade 100 from cement of grade 500, the proportions of mixing cement with sand should be 1:5 - for one bucket of cement, five buckets of sand (grade of cement 500: number of buckets of sand 5 = grade of mortar 100). To make the solution more elastic, add 50-100 g of detergent;
  • to obtain a mortar of grade 200 from cement of grade 400, you need to mix cement with sand in a ratio of 1:2 - for one bucket of cement, two buckets of sand (grade of cement 400: amount of sand 2 = grade of mortar 200). To make the solution more elastic, add 50-100 g of detergent.

Using this principle, based on the brand of cement, you can calculate the required mixing proportions to obtain the required brand of mortar.

Here the question immediately arises: in what cases are certain brands of solutions used? This is also determined quite simply - the brand of mortar is selected in accordance with the brand of building materials (bricks, blocks, etc.). If a brick of grade 100 is used, then the mortar is also selected of grade 100. By choosing a brand of mortar according to this principle, you will get almost monolithic masonry. But here, too, certain limits must be observed. For example, for facing masonry For bricks of grade 350, it is not at all necessary to use mortar of grade 350 - this is a senseless waste of money and materials. For facing masonry, a mortar of grade 115 is sufficient. To prepare it, you need to mix cement with sand in proportions of 2:7 or 1:3.5. The resulting solution, if prepared correctly, is quite resistant to the influence of wind and precipitation, which is important for the “face” of the facade, and is also durable - nails can be driven into the seam from such a solution. When preparing the solution, it is important to strictly observe the proportions. If there is a shortage of sand, it will dry out quickly, which will complicate the construction process, and if there is an excess of it, the seams may begin to crumble over time.

For backfill brick masonry of grade 75, the grade of mortar should also be 75. To prepare it, concrete and sand are mixed in proportions of 1:5.3 (one bucket of cement and 5.3 buckets of sand).

In cases where walls are built from various types blocks, a mortar of grade 100 is usually used to connect them.

When preparing a solution, it is not enough just to maintain the required proportions individual materials– you also need to know the sequence of mixing them. There are several “recipes”, the simplest and fastest of them is given below.

To prepare a classic (not dry) mortar, you need to prepare cement, sand, water and detergent. It is usually prepared in a mixer, which helps to obtain the most homogeneous mixture. First, water is poured into the mixer. The amount of water depends on the quality of sand and cement, as well as weather conditions. It is clear that when using wet sand or when preparing a solution under conditions high humidity less water is needed. On average, the amount of water should be approximately the same as the amount of cement, but it is better to pour less and then add more if necessary. When pouring sand and cement, there should be enough water to mix the solution evenly. If there is not enough water, the thick solution will not mix well. If you pour water at the very beginning, the solution will turn out to be too liquid and will spread.

Ideally, first pour in such an amount of water that the solution becomes liquid for better mixing, and after obtaining a homogeneous mass, you can adjust the density by adding water or a mixture of sand and cement (the proportions for a given brand of mortar must be maintained) in small portions.

As noted above, to improve the elasticity of the solution, detergent or liquid soap. Depending on the quality of the product, as well as other factors, its quantity ranges from 50 to 100 g. It is added directly to the mixer after water and before filling the cement-sand mixture. The detergent should completely dissolve in water and form foam. This usually takes about 3-5 minutes. It is undesirable to pour it at the end of preparing the solution, because in this case it will not completely dissolve and will not be distributed evenly throughout the entire volume.

Then half of the previously determined amount of sand is poured. For example, for a mortar with a cement to sand ratio of 1:4, you first need to fill only 2 buckets out of four.

Next, all the cement is poured into the mixer. In just a couple of minutes you should get a homogeneous mass. The second part of the sand is poured into it. Now is the time to check the thickness of the solution and, if necessary, adjust it by adding water or cement-sand mixture. After 3-5 minutes the solution is ready.

A high-quality solution should resemble sour cream in thickness - not too thick, but not runny either. If you run your finger across the surface of such a solution, a clear, not blurry trace should remain.

As you can see, there is nothing complicated in preparing the solution, and its preparation takes less than 20 minutes.

To obtain a high-quality solution, it is important to use the right materials. Water should be as clean as possible, without impurities and additives. You can use water from wells, boreholes, water supply or natural reservoirs.

Detergent added to the solution can be anything: for washing dishes, washing powder, shampoo, laundry soap, etc. The main thing is that it completely dissolves in water and foams well. This makes the solution more elastic. Do not add cleaning agents to the solution. Some manufacturers of building materials, for example, Fagot bricks, in recommendations for the use of their products, advise not to add detergents, since they allegedly spoil the quality of building materials and lead to cracks in the bricks. In fact, this is not so, the same “Bassoon” brick becomes covered with cracks even without the help of a detergent. Still, you need to be careful with detergent. Too much of it in the solution will cause foaming, causing the solution to look like cotton wool. Optimal quantity 50-100 g per batch.

Sand for mortar, especially for facing masonry, should be as clean as possible, without any admixture of clay. The presence of clay will significantly reduce the quality of the solution, since over time, under the influence of precipitation and wind, the clay will be washed out of the seams, leaving behind holes and cracks. To determine the quality of sand, a simple visual inspection is sufficient. Clay gives sand its richness yellow, so if you are offered yellow sand when purchasing materials, know that it has just come from a quarry and has not been cleaned. It can also be used, but not for facing, but for backfill masonry.

Digging a little from the topic, we note that clay sand is also not suitable for preparing concrete for various load-bearing structures, for example, reinforced belts, lintels, crossbars, etc. Clay significantly reduces the quality of concrete.

For the mortar for facing masonry, alluvial sand is used, which, after being mined in a quarry, is thoroughly washed, as a result of which it contains practically no clay and small stones.

From cement The quality of the solution directly depends. The higher the grade of cement, the less it needs to be added to the solution, as can be seen from the calculations given at the beginning of the article.

To prepare the solution you can use the following types cement:

  • Balakleevsky cement, grade 400, marking ShPTs III/B-Sh-400;
  • Amvrosievsky cement, grade 400, marking PTs II/B-Sh-400;
  • Balakleevsky cement, grade 400, marking PTs II/B-Sh-400.

There are other manufacturers, but, for example, Kiev cement (PTs II/B-Sh-400) is slightly weaker than those listed above, which means that its consumption is higher. When preparing a solution of such cement, you need almost 2 times more, although it also seems to be a 400 grade. Such an overexpenditure of materials and money is unjustified, so it is better to immediately purchase high-quality materials.

Sometimes developers want to see unusual seams on the facing masonry gray, but darker ones. Such contrasting seams make the masonry clearer and more attractive. As dye for solution You can use graphite or carbon black. It should be noted right away that such additives reduce the strength of the solution, which becomes brittle. In addition, the color of the seams will fade over time in the sun and be washed out by rain. Typically, seams retain their color for no more than 10 years. But there are other ways to change the color of the solution. One of them is to increase the grade of the solution by preparing it in proportions of 1:3. The more cement there is in the solution, the darker it will be. For the solution, you can also choose dark cement, for example, Balakleevsky grade 400 (ShPTs III/B-Sh-400), which is one of the darkest among other cements.

Since construction can be carried out not only in summer, but also in late autumn and even winter, it is necessary to take into account the influence of negative temperatures on the quality of the prepared mortar. Let us consider in more detail the methods of protecting the solution from frost.

To construct facing masonry at a temperature not lower than minus 5 degrees, you do not need to add anything to the solution. If the temperature is lower, the solution may lose its strength and may crumble after drying. Most often, semicircular jointing crumbles. To protect the seams from fraying, you can add potash to the solution. It perfectly protects the solution from low temperatures and at the same time quite cheap.

Backfill masonry can be erected without special additives at temperatures not lower than minus 10 degrees. If the air temperature is lower, potash is added to the solution.

When preparing a solution at sub-zero temperatures, it is necessary to take into account the effect of temperature on the quality of individual materials.

The biggest problem is sand that has frozen. Using it to prepare a solution is quite problematic. Therefore, when purchasing sand, it is best to store it indoors. IN as a last resort, it can be specially heated.

For better mixing, it is better to pour heated water. In addition, a warm solution will take longer to cool in the cold, and the detergent will dissolve in water faster.

To prevent the solution from freezing during operation, you can add special substances to it that prevent freezing. True, on modern market There are also liquid additives that themselves can freeze at sub-zero temperatures. To check the quality of such additives, you need to pour them into a separate container and leave for a while. If the liquid is frozen, there is no point in adding it to the solution.

A proven and reliable additive that protects the solution from freezing is potash. The instructions on its packaging tell you in what quantities and under what conditions it should be used.

That's all the advice on preparing mortar for masonry. Now there should be no problems with its preparation.

Cement can be used as a building material in the cold season, but you should prepare to ensure quality preparation when concrete takes a little longer to harden at low ambient temperatures.

There are many precautions that you must take into account to protect the work area over the long period of time while the material cures. It is also useful to use special products that make the job easier.


Freezing of water in solution

Newly laid concrete is at risk of being damaged if the water in the solution freezes because... Ice expands when it freezes and this can destroy the crystalline structure and bonds between the aggregate material and the cement powder.

Ultimately, this leads to a decrease in the strength of the concrete, increasing porosity and causing a loss of durability and post-processability, small pieces during processing of concrete destroy the integrity of the surface.

The work may not be completed if the temperature is less than 5°C and frost is expected within the next 24 hours.

Warm water

Consider using warm water for mortar instead of cold when temperatures start to drop, and be sure to ensure that bricks and blocks have been properly protected from frost.

Protection with plates

Consider protecting with boards wrapped in plastic and/or other insulation, but keep them supported to prevent them from sticking to the surface.

Shields

Vertical shields are also a good way to protect yourself from cold winds, because even in not very cold weather strong wind may damage unprotected concrete.

Ice protection

There is something else you can do to help, especially during the preparation period, make sure that snow or ice does not get into the solution. Always remember - material that has a thin cross-section runs the risk of being more damaged by the freezing process than thicker material and therefore requires better protection.

Complete the work as quickly as possible during the day before temperatures drop below zero in the evening.

Products for working in the cold season

Use special products for winter work. For example, Portland cement, which quickly dissolves and hardens. It contains additives specially formulated to increase structural strength and durability and can be used for repairs and cold weather construction where the process needs to be accelerated and improved.

Further work can be continued within a few hours.

Application

Typically, such concrete is used when installing wells, tiles, and repairs. basements, concrete paths and steps.