Calculation of concrete for floor screed online. Screed calculation. Sand cement SNiP

The consumption of cement per 1 m2 of screed is an important indicator that allows you to determine the required amount of the composition. The quality characteristics of the solution are affected by the ratio of the components that make up its composition.

What is the screed for?

A screed is a sand-cement mixture. It is used to level the surface or to create a coating before starting finishing work. In addition, its functions include hiding communication nodes. Hydro and thermal insulation is applied to the floor screed.

A positive feature of such a screed is its demand, because the composition is suitable for any finishing floor. This construction option is considered affordable, since all the necessary components can be purchased at reasonable prices in a specialized store. The coating is quite durable, the service life is several years.

In addition, such a composition is able to isolate sound, which is important when building apartment buildings.

• covering for technical purposes, which will remain final (floor in the garage);
• intermediate element for further installation work;
• in the form of a continuous coating (in order to level the surface);
• self-leveling mortar (it is quite liquid, so an airtight base is required).

In the latter case, the surface does not need to be leveled, since the composition itself spreads over the treated area.

Preparation for DSP consumption

It is prepared with the addition of water to bulk substances. Most often, builders prepare the composition directly on the site, but you can purchase a ready-made composition (it is more expensive).

In the factory mixture, in addition to the components presented, there are plasticizers and other additives. Thanks to them, the solution becomes homogeneous. Some brands can be used at low temperatures, because they contain frost-resistant substances.

Different manufacturers have different products in some respects. The ratio of substances depends on the destination. When concreting, sand is taken in a smaller amount; masonry requires a large mass of the substance.

For better adhesion of the components, it is recommended to mix the solution by hand. The standard is 1:3. In some cases, other proportions are used (1:2 or 1:4).

The calculation of cement for screed helps save money on the purchase of materials. The final indicators are not always accurate, because sometimes there are no data on the density of substances.

1. M100. Used for alignment. Consumption is 550-570 kg/m³.
2. M150. For laying bricks and cinder blocks, installation and concreting (570-590 kg/m³).
3. M200. The mixture is intended for masonry and installation (590-620 kg/m³).
4. M300. Filling sites with increased load and concreting (620-660 kg / m³).
5. M400. For installation of high-strength concrete structures (660-710 kg/m³).

When calculating the amount of materials per 1 m2, it is possible to determine the brand and amount of the substance with great accuracy. You can replace 1 type of composition with another, the quality of work does not deteriorate.

We calculate the solution and consumption of the screed

Construction work on pouring the floor must be carried out continuously. The prepared mixture cannot stand for a long time, because it loses its properties. Under such conditions, it is required to calculate the consumption of materials.

• the area of ​​the processed room;
• the initial quality of the coating (the thickness of the layer depends on this);
• brand of goods;
• sand quality.

• the presence of plastic components in the composition;
• sulfate resistance;
• percentage of additives;
• the level of load that the coating must withstand.

Many novice builders do not know how much material to purchase. There is no standard formula, so everyone uses their own calculation system.

After setting the zero level and calculating the required thickness, the area of ​​\u200b\u200bthe room is determined (for example, 10 m²).

The resulting figure should be multiplied by the height of the screed (50 mm). As a result, 0.5 m³ of cement is needed to fill the indicated area.

1. The mixture consumption per 1 m2 of screed with a thickness of 5 cm is about 20 kg/m2.
2. When this figure is multiplied by 0.5 m³, 1000 kg is obtained.
3. When dividing the result obtained by the weight of 1 bag (50 kg), you get 20 pcs.

A layer 10 cm thick will require 50 kg of cement for an area of ​​1 m². In the course of work, the material gets even into small cracks, therefore, when calculating the amount, it is recommended to take the material in excess (by 25-30%). When kneading, the solids decrease in volume due to the combination with water, so the final volume will be much lower.

1. The dry ingredients are mixed first. It is recommended to observe proportions to the nearest kilogram. Otherwise, the batch will turn out to be of poor quality.
2. Any plasticizers and liquid additives are initially combined with water. should be used depends on the brand. The instructions indicate the exact proportions. You should not save on material and take a smaller amount, because this will negatively affect the quality of the coating. On average, for 1 bag of cement for floor screed (weighing 50 kg), 200 kg of plasticizer will be required.
3. When mixing a dry substance with a liquid, the latter gradually pours into the container with the powder, and not vice versa. It is recommended to constantly mix the mass and prevent the formation of lumps.

• mixer;
• drill.

In this case, the mixing process will take much time.

Nuances in the calculation of the CPV

To determine the amount of floor screed mixture, all components are taken into account. The correct ratio of substances affects the final result.

1. Technical premises (floor in the pantry or garage).
2. A preliminary layer with a thickness of 8 cm. The best option is a concrete mixture with a large fraction. It is recommended to use a sand-cement mortar.
3. The final version, intended for further cladding with decorative elements. The thickness of the coating is from 5 to 30 mm.

1. Freeing the room from all that is superfluous with a vacuum cleaner, hard broom or brush. If necessary, the previous coating is removed.
2. Damage is being assessed. Large cracks are treated with putty so that the composition does not seep through them. You can use foam for installation work.
3. The floor is being marked, beacons are being installed. Zero level is set at any point in the room. For this purpose, special tools are used. From the specified point, the marking of the room is made.
4. All marks are connected. In this way, the height difference line is established. This indicator should be in the range from 5 to 8 mm. With large differences, the surface should be leveled, otherwise the composition will undergo cracking.
5. Taking into account the measurements of the height difference, the final layer thickness is determined.

It is best to fill the room at a time, because uneven solidification of the solution will lead to cracks and inconsistencies in level.

Filling starts from the corner located on the opposite side of the door. After that, the surface is leveled. For the next 12 hours, a polyethylene film is applied to the base. After the specified time, you can start mashing.

Before determining the consumption of a substance per 1 m3 of solution, the technical characteristics of the material should be taken into account. Some dry matter grades require large amounts of sand. At the same time, the concentration of the cement itself decreases. A screed made with an inaccurate calculation may not withstand the predicted load and will quickly undergo destruction.

To further strengthen the solution, it is recommended to add PVA glue to it, which can replace the plasticizer.

If you are satisfied with the order of prices, indicate your name, phone number, e-mail address by filling in the appropriate fields, add comments and click the "Submit" button.

The calculator will send an application for a revised calculation to us and a copy of the application to the address you specified.

Floor screed area (roof)

To calculate the cost of materials and work, you must specify the area of ​​the screed. If the screed is needed for several rooms, indicate their total area.
If necessary, a specialist from the M-plasterer company can be called to the object for measurement. This service is free.

Thickness of floor screed (roof)

If the base of the floor (roof) has significant differences or there are several rooms at your facility with different requirements for the screed, indicate the approximate thickness to calculate the price. Then, if the order of prices suits you, send a request for an updated calculation, which we will make after the departure of our specialists to the site for instrumental measurements.

Please note that the thicker the screed, the more it weighs. If you need to reduce the load on the base of the floor screed, select the option "Polystyrene concrete base 50 mm" for the calculation.

Polystyrene concrete is a material with a low specific gravity. At the same time, in comparison with expanded clay, polystyrene concrete is lighter, cheaper, its fractions have a smaller variation in size (which has a positive effect on the performance properties of the screed). Polysterol concrete has better adhesion with cement laitance than expanded clay, less shrinkage, higher strength.

Work floor

If the floor screed needs to be done in a multi-storey building, indicate the floor of the work.

The mixture for semi-dry floor screed will be produced at the construction site using modern German technology and delivered to the work floor by a hose that can be pulled up to the 20th floor. Thanks to this, we ensure high productivity and cleanliness at the facility. What is especially important in the case of work in public buildings and apartment buildings.

Remoteness of the work site from the Moscow Ring Road

If the floor (roof) screed needs to be done in Moscow, leave the value of the “Distance from the Moscow Ring Road” field equal to zero.

If your object is located in the Moscow region - to calculate the cost of delivery of materials and equipment, indicate how many kilometers from the object where you need to make a screed to the Moscow Ring Road.

If the distance from your object to the Moscow Ring Road is more than 100 km, leave the field value equal to zero, calculate the cost of the screed and send us the calculation (indicating your contact details in the fields “Name”, “Phone number”, “E-mail” and describing the location of the object in the field “Your comments"). We will calculate the cost of the screed, taking into account the costs of purchasing and delivering building materials from suppliers in your area.

We use our own modern fleet of vehicles to deliver materials and equipment to the place of work.

Site for placement of building materials and equipment

Indicate the presence at the facility of a street site with an area of ​​at least 20 m2 for placement of building materials (bulk and in bag containers) and equipment for the manufacture of a semi-dry cement-sand mixture. Please note that it must be possible to bring tap water to the site (water hoses).

In special cases, which are agreed on the results of the visit of the M-Plaster specialist to the site, the site can be equipped at a distance from the place of work. The main thing at the same time is to solve the issue of protecting the hoses, through which the finished mixture will be supplied to the place of work, from collision and damage.

Almost every overhaul is not complete without arranging a floor screed. This process allows you to make a solid foundation that will serve its owner for decades. The quality of the screed directly depends on the materials that were used in the process of its manufacture. In order to avoid unnecessary expenses for their purchase, you should carefully calculate the required amount of sand, cement and various components that will be needed during the work. We will talk about how to do this later.

Floor screed - features and technology

Floor screed is a concrete-sand layer that covers the entire surface of the floor before applying finishing materials. With the help of arranging the floor screed, it is leveled and the strength characteristics are improved.

The screed is an excellent base for laying any floor covering. In addition, a communication system is hidden under the screed, a ventilation gap is arranged, and waterproofing and insulation are laid on the screed. There are two main purposes of screeds:

• topcoat, for example in a garage;
• an additional layer for laying finishing materials.

In relation to the installation method of the screed, there are:

• connected - the screed is laid directly on the floor surface and connected to it;
• with the presence of a separator - a waterproofing and heat-insulating space is arranged under the screed, in this case, the screed is connected only to the walls of the room;
• floating type of screed - with the help of this screed, reliable sound insulation is provided, the screed is settled on the heat-insulating and waterproofing layers, and does not touch either the floor or the walls.

In relation to the installation method, the screed is:

• solid type - produced by filling the space and leveling the cement mortar;
• self-leveling type - it has a high level of fluidity, requires a sealed base for application, does not need leveling, since it spreads on its own due to its large weight;
• a semi-dry floor screed consists of two layers, the first of which is dry and the second is conventional, in this way it is possible to reduce the cost of the screed manufacturing procedure, since the amount of mortar required for its arrangement is significantly reduced, a semi-dry screed gains strength due to the use of special compounds polymer-based, which are positively negative on the quality of adhesion and improving the quality of the floor;
• the prefabricated type of screed is also called dry, the surface of such a screed is leveled using a flooring of bulk materials, for example, expanded clay gravel, then concrete slabs are laid, this method of arranging the screed does not require the presence of a concrete mixture.

In addition, there are two special types of screed:

• industrial - using a high-strength concrete composition, floor treatment using special compounds that improve its quality, this type of screed has a special strength, it is resistant to chemical compounds and other irritants;
• semi-dry type of sand-cement screed - this type of screed uses synthetic fiber, such a screed is comparable in strength to a reinforced concrete base.

Floor screed, calculation of materials and features of its implementation

Conducting a calculation of materials for arranging a screed is a fairly simple process that is easy to perform with the right approach to it. In order to calculate the required amount of materials for the screed, you will need to perform the following steps:

1. For example, for a floor area of ​​20 square meters, when applying a screed of 50 mm, 1 cubic meter of solution is required. That is, 20x0.05 = 1.

2. To calculate the amount of cement and sand from which the solution will be prepared, you must first determine their proportion. It, in most cases, is one to three. That is, for one part of cement, three parts of sand are needed. 0.25 cubic meters of cement and 0.75 cubic meters of sand are needed to equip such a screed.

3. Now we translate the obtained data into kilograms. The approximate weight of one cubic meter of cement is 1.3 tons. That is, we need about 330 kg of cement.

Please note that when making a concrete solution, it shrinks a little and reduces the volume. For example, when using one cubic meter of mortar, you will end up with about 0.7 cubic meters of screed. Therefore, after the calculations, the amount of materials should be increased by 10-15 percent.

Features of preparing a mixture for screed

After making calculations on the materials for arranging the screed and after purchasing them, an important process follows - preparing a solution with which the floor screed is poured.

There are several types of screed compositions, they differ in composition, proportions of ingredients and the type of coating on which they are applied.

Most often, the following components are present in the composition for the manufacture of screeds:

• cement, the higher its grade, the stronger the screed will be, the best quality cement is used in industrial types of screeds, cement grade 400 is enough for a standard screed;
• sand - before use, this material is sifted, the remains in the form of stones and debris are removed, please note that the sand must be dry, the presence of a small amount of moisture will adversely affect the quality of the screed;
• to improve the quality of the concrete composition, the use of plasticizers is recommended;
• materials in the form of polymeric and mineral additives make the laying of finishing materials easier, help to accelerate the curing of the screed, etc.

In addition, some formulations involve the use of gypsum as a binder. These solutions are characterized by a high drying rate, they are not prone to shrinkage, their scope is limited to dry rooms. In a room with high humidity, the installation of such a screed is unacceptable.

Tip: When buying cement, pay attention to the period of its manufacture, since long-term storage leads to excessive accumulation of moisture in the cement and this composition is of poor quality.

It is possible to purchase a ready-made mixture, but such an event will cost many times more.

Calculation of floor screed and mortar manufacturing technology

The procedure for preparing the solution must be carried out carefully and in compliance with all technologies, since the final result of the resulting screed depends on this.

To prepare the solution, we suggest that you familiarize yourself with the recommendations that will help you do this:

1. All bulk and dry materials are mixed together separately. Please note that the proportions must be observed to the nearest kilogram. If the proportionality of the ingredients is violated, the quality of the composition deteriorates.

2. Plasticizers and water are combined separately and thoroughly mixed. Most often, for one bag of cement, the weight of which is 50 kg, about 200 grams of plasticizer is required. More precise instructions are written in the instructions for its use.

3. After the preparation of dry and liquid components, the procedure for mixing them together is to be done. Dry materials are slowly poured into the water, monitor the uniformity of the mass and the absence of lumps in it.

Tip: To evenly stir the solution, use electric tools in the form of a mixer or a special drill. They will make the solution homogeneous, and the procedure for its preparation will be significantly accelerated.

To make the calculation of the floor screed mixture quick and easy, we suggest that you familiarize yourself with simple recommendations that will help in this matter:

1. The initial stage involves the calculation of the required amount of concrete, it includes:

• determination of the thickness of the screed;
• multiplying the obtained values;
• multiplying the results by the value of the original coefficient, which is 1.02.

2. Convert cubic meters to kilograms. In relation to building regulations, one cubic meter of mortar contains about 500 kg of cement. The calculation of cement for floor screed should be multiplied by three, since its ratio in the solution is one to three. Thus, we find out how much sand is required to prepare the solution.

3. After the calculation of sand concrete for floor screed, it remains only to purchase materials and begin work on the construction of the screed.

Calculation of mortar for floor screed

There is an option to purchase ready-made mixtures, in which there are special additives that provide additional reinforcement of the screed. Working with them is simpler, since there is no need for independent calculation of the components, their correct connection and preparation. Simply open the bucket with the finished mixture and use it for its intended purpose.

In addition, these compositions are equipped with instructions that describe in detail not only the preparation of the solution, but also its consumption for a certain floor area.

These compounds are quite expensive, although the procedure for performing work with their use is much simpler.

The packaging contains the value of the volume of the mixture. To prepare it, it is enough to use only water and bring the composition to the desired consistency, in relation to the selected type of screed.

To prepare the solution, it is preferable to use a bucket and a mixer. Do not use an ordinary shovel, as it cannot be used to prepare a perfectly mixed concrete composition. First, water is placed in the bucket, and then the mixture is gradually poured out.

Calculation of the amount of screed for the floor: making a screed

There are several stages in the construction of a floor screed:

• preparatory work;
• installation of lighthouses;
• solution and its preparation;
• direct filling process.

In order for the final result of the work to please with quality, one should strictly adhere to the manufacturing technology of the screed.

Foundation preparation consists of the following steps:

• sealing all cracks with a solution;
• cleaning the surface from dust and dirt;
• floor treatment with soil.

Please note that the choice of one or another type of primer directly depends on the type of surface on which it will be applied. Carefully follow the technical characteristics of the material, and choose a primer for floor treatment.

The next step is the installation of beacons. They look like guides that are installed indoors. When pouring the floor along the beacons, a rule is carried out, as a result, the surface is even and smooth.

Please note that incorrectly installed beacons lead to a violation of the horizontal floor, to the appearance of its curvature and unevenness. Aluminum profiles are used as guides.

Do-it-yourself floor screed, calculation and installation of beacons

Installation of beacons for floor screed is as follows:

1. Determination of the zero level, approximately 50 mm from the floor.

2. Designation of a line that runs near the wall. Holes should be drilled in each of its sides, and self-tapping screws should be installed.

3. Install the aluminum profile, check its evenness with a level. By tightening the screws, set the profile in a perfectly flat position. Check its horizontal position several times, since the evenness of the future screed will depend on this.

4. Fix the beacon with plaster mortar. Also, install other beacons. After installing them, check the evenness of each element again.

The procedure for filling it completes the manufacture of the screed. Try to produce it in stripes, in the space between the beacons. After the surface grabs a little, the beacons are dismantled. If there are light spots on the surface, they are eliminated using a solution with a rule.

In order to prevent cracks from appearing on the floor surface, moisten the solution with water for a week after pouring.

Arrangement of a dry screed and features of the calculation of expanded clay for floor screed

The manufacturing technology of a dry floor screed has its own characteristics, it does not need to make a cement mortar and carry out wet work. To build a dry screed you will need:

• waterproofing;
• thermal insulation materials;
• bulk material in the form of sand, expanded clay, slag or gravel;
• slabs of asbestos cement, moisture-resistant gypsum fiber or chipboard.

Stages of work on a dry screed:

• laying a waterproofing layer;
• providing thermal insulation;
• tamping and leveling with bulk material;
• slab laying.

In relation to the type of material used in the work, the cost of such a screed is determined. It is not recommended to equip a dry floor screed in a room with high humidity.

One of the cheapest, but at the same time high-quality materials used in the arrangement of the screed is expanded clay. It is made from foamed clay, which is fired in a special kiln. Therefore, expanded clay is absolutely harmless to health. If you plan to equip a screed with a thickness of more than 50 mm, then the use of expanded clay is ideal.

The thermal conductivity of such a screed is at a high level, in addition, there is no load on the building, and the cost of purchasing materials is reduced.

For 10 square meters, with a layer thickness of 1 cm, 0.3 cubic meters of expanded clay is needed. If you translate this value into liters, then you need to purchase 100 liters of expanded clay.

For a more detailed calculation, you should initially determine the height of the screed. If the room is located on the ground floor, then the minimum layer thickness should be 100 mm. Otherwise, 40 mm will suffice.

In the process of repairing an apartment or a private house, an important step is the preparation of the subfloor - laying the screed. The most popular and long known cement floor screed. If you decide to make repairs yourself, then you probably wondered what mixture to purchase, how to calculate how much it will be needed.

Peculiarities

Cement screed does not lose its relevance due to the fact that it fits under any finishing floor. It is made from a mixture of cement and sand and diluted with water. Then the resulting solution is poured into the room. This method is known as "wet". The reasons for the popularity of this type of screed:

• Availability. Ingredients or ready mixes are easy to get at any hardware store.
• Coating strength. A sufficiently thick layer (usually more than 20 mm) ensures the reliability and durability of the floor.
• The ability to isolate sound. In modern apartment buildings, this quality is extremely important.
• Suitable for underfloor heating. At present, in private houses, in bathrooms of apartments, floor heating technology is often used. It is convenient and practical. Electric or water heating systems can be easily and safely "hidden" in the cement layer. In addition, it has good thermal conductivity, and heat loss will be minimal.
• Pipes and other communications can also be hidden with a cement screed.
• After drying, the layer practically does not deform, does not shrink. You don't have to worry about its integrity.

With all this, there are several negative points:

• the work is hard and hard. It will not be easy for beginners to cope with laying the layer;
• the solution is not suitable for old and wooden floors due to the large weight;
• if you require minimal deviations for a decorative floor, then a leveling layer of another mixture will have to be laid on the cement screed;
• the usual solution dries for a long time, requires maintaining a constant humidity.

It is also necessary to ensure that there are no drafts and temperature changes during the drying process.

Varieties of solutions

The variety of types of screed in the construction market is constantly growing. The basis of the composition is sand. It is best when it is purified, white, without the admixture of clay. The presence of clay in the composition can lead to the loss of high strength characteristics of the future screed. Various additives and plasticizers are being developed, with the help of which certain specified properties and characteristics of the mixture are achieved. The second main component in the solution is cement or gypsum.

The solution with the addition of cement is durable, such a screed can be used in rooms with high loads. The mixture can be used at high humidity. Cement is budgetary, so it is widely in demand, but it must be laid in a layer of 2 cm or more, otherwise the desired effect will not be achieved. In the case of plaster, the work is somewhat easier. The surface is more even. The layer can be thin, up to 2 cm, while the strength and resistance to stress will remain high.

The mixture dries quickly and does not shrink. A significant drawback is intolerance to moisture.

There are three types of cement screed that can be laid indoors.

Related

The name itself suggests that the screed is connected to the base. There are no interlayers between the floor slabs, walls and subfloor. This method is used if it is necessary to achieve a layer thickness of not more than 40 mm. The foundation must be carefully prepared. All cracks and chips must be repaired with a repair mortar, minor irregularities can not be eliminated. Before laying the bonded screed, the surface is treated with primer solutions for better adhesion of the cement mixture to the base.

The mixture is diluted to the consistency of thick sour cream, then immediately poured onto the floor surface. After 20 minutes, the screed begins to harden. This process is really long, this is the big minus of the method. If a large surface is being processed, then it is impossible to cope with the work alone.

Unrelated

Here the layer can be more than 40 mm. Waterproofing must be laid under the screed. This will protect both the base from moisture penetration during the pouring of the screed, and the draft layer from moisture coming from outside (for example, if the floor is made on the first floor of a "high-rise building" or in a private house).

floating screed

It is laid on a heat or sound insulating layer. Its thickness may be different, but when it reaches a height of 3-4 cm, it may be necessary to reinforce.

Depending on how much water is added, the screed is divided into wet and semi-dry. Wet screed is a well-known and widely used method. So, the coating must be carefully leveled, and waterproofing should be used so that the moisture from the mixture is not absorbed into the base and does not impair the strength characteristics.

A semi-dry screed is obtained due to the fact that the water rate is reduced. The composition has a porous thick texture, similar to a sand mixture. It is easier to level and there is no risk of flooding neighbors.

A cement screed, unlike a concrete screed, is used exclusively indoors, although concrete screeds are also made on the basis of cement and sand mixtures with the addition of various fractions of additional materials. In terms of cost, they practically do not differ. There are two ways to prepare a cement screed:

• Dilute ready-made mixtures, which are sold in large quantities in hardware stores. You only need to study the instructions, add the right amount of water and stir the mixture with a construction mixer. Cement mixtures of the brands Knauf, Bergauf, Perel, Hercules, Prospectors are widely known. The mixture is packed in bags of 25 or 50 kg. Such packaging is more convenient for transportation, because the cement is quite heavy. Ready-made screeds have a lot of advantages over homemade ones. Various plasticizers can be added to them to improve strength characteristics and speed up drying.

• Prepare the product yourself from cement, sand and water. In this case, you need to carefully approach the choice of cement brand, observe the proportions of water and sand in the solution. The numbers in the marking of cement (M200, M400, and so on) show what maximum load it can withstand. For apartments, the M150 and M200 brands are suitable.

The Importance of Proportions

If only water is added to dry ready-made mixtures, the required amount of which is indicated on the package, then when preparing the solution on their own, the proportions are not always kept perfectly. Compressive strength is extremely important. Above it was mentioned about the maximum loads and markings of cement. So, cement grade M150 can withstand a load of 150 kg per square centimeter, its compressive strength is 12.8 MPa. The higher the grade, the greater the strength. In cases where a specific brand is not specified, they are guided specifically by the M150.

To perform the screed in the apartment, it is advised to use cement grades M400 and higher.

The quality of the sand also affects the overall characteristics of the mix. For high strength and quality characteristics of a cement screed, it is better to use sand with an impurity content of less than 5%. In the event that you use more contaminated sand, the final result will become completely unpredictable. After purchasing the sand, you can verify its reliability by adding some of it to a water bottle. If, after stirring, the water acquires a cloudy brownish tint, then such sand should not be used.

If for some reason you are still not sure about the ingredients, then it is advised to increase the amount of cement by 20%, reducing the volume of water. The importance of maintaining proportions will affect the strength, moisture and heat insulation characteristics of the screed. The ratio of sand and cement also depends on the expected maximum load on the screed. To fill the floor in non-industrial premises, as a rule, DSPs are made on the basis of M150 or M200. Cement M400 and sand are taken in proportions of 1: 3 or 1: 2.8. Water is added at a ratio of 0.45-0.55 per 1 m2.

It is necessary to ensure that the solution is homogeneous, does not spread and does not exfoliate, and does not have clots. This is important to maintain the strength of the screed. If you use more water, the screed will be too liquid, will harden for a long time and will lose the desired technical parameters.

What affects consumption

The calculation of the required amount of mortar is usually done on the basis of consumption per square meter. This expense is affected by many conditions, so there is no single calculation mechanism. There are several factors that affect the amount of ingredients in the mixture:

• builders know that the quality characteristics of the screed are affected by the shelf life of the cement, so it is recommended to use a powder that was released no more than 6 months ago, otherwise the strength of the coating will be reduced by at least 10-15%. If the cement is older, then to secure its share is increased.

• The unevenness of the base is the main factor affecting the increase in the consumption of the mixture. It is not enough just to know the area of ​​the surface to be poured. It should be taken into account that in the presence of deep cracks and strong surface drops, the flow rate increases by 50%, so measurements should be carried out in several places.
• To save cement, various large fractions such as expanded clay or crushed stone can be added to the mixture. This turns the mortar into sand concrete and can significantly change the properties of the coating.

• The amount of the mixture directly depends on the type of screed. In cases where it is unbound or floating, the height of the coating is more than 4 cm, so the consumption of materials increases.
• The brand of cement and the purpose of the resulting mixture affect the ratio of dry powder and sand.
• Laying communications is another condition that can greatly affect the consumption of the mixture. The diameter of the pipes is the main factor for increasing the volume of the mixture. The screed layer over communications can reach 5 cm in height.

• If a technological slope is set (which is relevant for the bathroom), then the differences should also be included in the calculation of the finished mixture.
• If you want to achieve not only DSP savings, but also an increase in thermal insulation characteristics, then not only the addition of large particles will help, but also an increase in the height of the mixture. A wet screed with expanded clay to preserve heat should be laid in a layer of at least 10 cm.

Nuances of counting

When performing calculations, pay attention to the following points:

• The purpose of the premises should influence the choice of brands of components and the composition of additives. For warehouses, industrial premises with a heavy load, you need to choose cement with higher rates to increase the strength of the floor.
• If the rough coating needs to be laid with a layer of 80 mm or more, then the use of sand concrete will be effective.

If high loads on the coating are not planned, then it is possible to mount the DSP with the laying of a reinforcing mesh.

The device of an even and solid floor base is the main purpose of the screed. There are several methods for its device. They differ in the method of manufacture - for example, using water when mixing the solution or only dry materials. In turn, "wet" screeds can differ in the type of binder - there are screeds based on cement, and there are screeds based on a gypsum binder. Our calculator allows calculate screed and consumption relevant materials. As reference values, we use the results of calculations for a screed, which is made in the traditional way - using water and sand concrete - a ready-made mixture that contains cement itself (binder) and sand (aggregate), as well as in some cases special additives (for example, fiber - cm. ). We compare the results obtained with calculations for other types of screeds - for example, for prefabricated floors. With the help of such calculations it is possible to represent in general difference between ties, in particular, determine the load on the floor (find out the weight of the screed, depending on a particular technology).

The length and width of the room are indicated in meters; layer thickness is in millimeters.

How to calculate the screed (including expanded clay)

With our calculator, you can determine sand concrete consumption, expanded clay and other materials that may be required for the manufacture of floor screed. Currently, the calculation is made for the following types of screeds (depending on the total thickness of the leveling layers):

• classic sand concrete screed;
• screed, as in option 1, but only with the use of an underlying layer of expanded clay(allows to reduce the load on the ceiling, reduce the consumption of materials);
• cement-sand screed on a layer made using the so-called. "light screed" UBO;
• prefabricated floor base for laying flooring, the design of which consists of a loose layer and gypsum fiber boards.

Option number 2 is also used in the case of manufacturing mechanized floor screed when the total thickness of its structure exceeds 70 mm. In this case, the layer of the screed itself, made from a mixture based on a cement binder, is 60 mm. The remaining part is filled with a layer of expanded clay with its subsequent impregnation with cement milk. Such impregnation prevents the movement of expanded clay, compacts and fastens the underlying layer.

Under certain conditions (they can be set by the project or the requirement of regulations and specifications), the screed can be reinforced metal mesh and / or placed on a soundproof layer. In the latter case, it is customary to talk about a "floating screed" - it is not fastened to structural elements in any way (floor slab, walls, partitions, columns, pipelines, etc.). This makes it possible to reduce the impact of impact noise on the ceiling and enclosing structures, to prevent its transfer to neighboring rooms through sound bridges, which are formed, for example, in the manufacture of a screed fastened to the base. The calculation of materials for reinforcement and the manufacture of an insulating layer is carried out in the "Additional materials" section, where, in addition to their total number, the current cost is also indicated.

What else to look for when planning a floor repair?

It should be remembered that the installation of a screed in an apartment when the old floor is opened, its underlying elements, for example, backfill, are removed, and a new screed is poured instead, is essentially a change in the floor design. According to paragraph 2.2.6 of Appendix No. 1 to the Government of Moscow dated 10/25/2011, such work is recognized as a reorganization, for which it is required to prepare project and coordinate it with the Moscow Housing Inspection.

How much does the tie weigh?

In addition, in its decision to approve the redevelopment, the Moscow Housing Inspection may make a note that the work to change the floor structure should not lead to an increase in the load on the floor. This clause allows the supervisory authorities to accept the results of the work after their completion by actually examining the floor structure. Screed weight may be significant. Therefore, when planning a floor structure, it is necessary to take into account its total weight, and in some cases, use lightweight elements. Our calculator allows you to compare such technologies.

When calculating the screed, additional costs must be taken into account - the cost of delivery, unloading and lifting to the floor. Given the weight of the mix, these costs can be significant.