Calculator of cement mixture. Types of concrete for floor screed

The floor screed is an integral part of the floor of a residential, technical or production space. At the same time, the floor screed can serve as the basis for finishing the finish and as a "clean" coating for household and industrial premises.

the calculation of material per square meter of floor depends on many factors

Example calculation for a classic floor screed

Earlier, we already considered in detail. Before proceeding, for example, calculating the amount of cement and sand on the floor screed for a particular room, a number of assumptions should be made:

• Thickness of screed. According to the construction norms and rules, the minimum thickness of the reinforced floor screed is 2 cm, the maximum thickness of the non-reinforced screed is 4 cm. We accept the layer thickness of 4 cm as the most optimal and common option;
• Mark the solution. Recommended brands of solution: M150 or M200;
• Recommended brands of cement - portland cement M300, M400 or M500;
• Calculation of cement and sand is carried out in kilograms per 1 cubic meter of solution for pouring screed;
• Calculation of the volume of pouring is carried out in cubic meters. In other words, the length and width of the room, as well as the thickness of the screed layer, are measured in running meters.

So.   How much cement is needed for floor screed?, poured cement-sand mortar grade M200 (proportions of cement and sand 1: 3), on the basis of cement M400, single-layer, thickness 0.04 m for a room 4x3.5 meters?

We calculate the volume to be filled: 4x3.5x0.04 = 0.56 m3. To calculate the cement, use the table of the amount of binder per 1 m3 for grades M150 and M200, based on cement: M300, M400 and M500:

Brand of cement	Brand mortar
	M150	M200
Cement	Cement consumption per 1 cu. m solution
M500	330 kg	410 kg
M400	400 kg	490 kg
M300	510 kg	—

As follows from the table, for the preparation of 1m3 of M200 grade mortar based on M400 cement, 490 kg of binder (cement) is needed. Since we need to prepare not less than 1 m3 and less - 0.56 m3, the following arithmetic action should be performed: 490x0.56 = 274.4 kg of M400 cement is required for the preparation of mortar M200, for pouring a floor screed 4 cm thick in a 4x3 room, 5 m.

Calculation of the amount of sand based on the above proportion of 1 part of cement on 3 parts of sand (humidity not more than 7%): 274.4x3 = 823.2 kg of sand is required for the preparation of a cement-sand mortar for pouring a floor screed 4 cm thick in a room 4x3, 5 m.

Similarly, you can calculate the number of components for any thickness of the screed, for rooms of any size - multiply the "own" length and width of the room and the "own" thickness of the screed layer in meters. Using the tabular data to determine the amount of cement, then determine the amount of sand based on proportions.

Helpful advice! To increase the wear resistance of the screed, it is especially important for a "clean" floor screed, without fail, carry out the ironing of its upper layer.

The technology of "ironing" is as follows:

• Immediately after pouring IMPORTANT! and leveling the layer, sprinkle the surface of the screed with a clean dry cement layer of 3 mm;
• Sprinkle the surface with water until the cement is completely wetted;
• Light circular movements with a flat grout or trowel wipe the cement in the surface, which should take a uniform dark green shade with "blue".

Thus, a hard, wear-resistant and very strong crust is formed on the surface of the screed, reliably protecting the screed from abrasive and other mechanical impacts.

to curtail

Is the screed strong in concrete? What brand should it be? How much is it required per 1 m2 of floor?

Sand concrete for screed is a dry construction mix of coarse and fine sand, portland cement, chemical additives, increasing strength and moisture resistance. Brands:

• M-150;
• M-200;
• M-300.

Calculation of flow

To prepare 1 m3 of material, you need to spend 2000 kg of sandstone M300.

To determine the consumption per m2 coating we use the formula:

V = 2 x h

To calculate the consumption of the amount of dry mixture per room, we use the formula:

V = 2 × h × S

where V is the flow rate (kg), h is the thickness (mm), S is the area of ​​the room (m2).

you need 2 x 30 x 20 = 1200 kg (or 24 bags of 50 kg).

How long it dries

In general, the cement-based mortar gains full strength on the 28th day. But, firstly, some manufacturers use chemical additives that speed up the process. And, secondly, they quickly harden in the first week. Thus, the subsequent work can be done 7 days after pouring.

Prepare it much easier than the classic. This is especially convenient when repairing an apartment with your own hands. You do not have to mix cement and sand in cramped conditions, lifting dust. Unnatural impurities, in addition, increase plasticity and frost resistance.

We draw conclusions. Mark M300 is better suited for floor installation by hands.

Tips for choosing a mixture.

Advice in choosing the material.

When choosing a mixture it is necessary to pay attention to the packaging of the material, the manufacturer, the brand. If the artisanal concrete is of low cost, then the quality, respectively, of this is lower. Low quality is mainly determined by the use of low brands of Portland cement.

If you use a poor-quality material, it is more likely that you expose the metal components of the structure and the reinforcement of corrosion due to the high content of sulphides and chlorine. Also, when the composition dries, detachment may occur, the layer is spilled out.

Materials of factory execution, produced in large production volumes, are more reliable. In the composition of these sand-concrete can be added plasticizers, modifiers or improving the properties of the additive. But even these mixtures have a disadvantage - the absence of antifreeze additives. That is, at a temperature below 5 degrees the material is used
  is prohibited.

Delivery is very good, in Moscow, Yekaterinburg, Perm, Surgut, Nizhny Tagil and Chelyabinsk.

Sand-concrete - frost-resistant and durable material, which is often used in construction for the construction of rough floors. According to its physical and mechanical properties, the material is similar to a conventional cement screed. However, it includes various plasticizers and modifying agents that significantly improve the technical characteristics of the screed: mechanical and chemical resistance, frost resistance, density, etc.

What is sandstone?

If it is necessary to construct a basement with your own hands, the question often arises: what material should be used for pouring screed? Traditional cement-sand mortars are inexpensive, but in the case of creating a decent mechanical load on the coating begin to crack. Similar disadvantages are devoid of a liquid mixture of sand concrete. What is it?

Sand concrete is a special composition, which includes the following components:

• portland cement;
• synthetic substances (plasticizers, pigments);
• sand.

The above substances affect not only the consistency of the solution, but also the wear resistance of the screed itself. Depending on the fraction of sand that enters the mixture, the sand cement can refer to fine-grained and coarse-grained concretes.

Analysis of the composition of sand concrete

In the process of finishing the rough floor with their own hands, one must take into account a number of characteristics of the coating:

• presence of temperature differences in the room;
• the intensity of the exploitation of the floor;
• humidity level in the room;
• type of foundation or overlap (the presence of a basement floor).

When making bases in rooms with a specific microclimate, it is not necessary to use an ordinary cement screed. Why? The formed coating has a high hygroscopicity and capillarity, so the moisture penetrates into the bottom of the base unhindered and destroys the reinforcing mesh. Over time, this affects the integrity of the rough and finish floor.

What kind of material in this case is best to choose? As practice shows, sand concrete has good moisture resistance and frost resistance. You can not discount the low consumption of the material itself, which is due to the high plasticity and fluidity of the solution. However, the technical characteristics of the sand and cement composition are affected by the concentration and availability of individual components.

But whatever mix for the rough floor you choose, it will definitely include such substances:

• granite screenings;
• fine or coarse-grained sand;
• portland cement.

However, the technical characteristics of the screed are affected by the additives included in the mixture, which include:

• plasticizers;
• antibacterial substances;
• retarders and accelerators of the screed hardening process.

Which sandstone is best to choose in this case? The variety of the chosen composition directly depends on the conditions of use. In the process of pouring a solution onto a small area of ​​the substrate, it is more expedient to give preference to solutions with a fast pour point. If it is necessary to equip the rough floor of a larger area, it is better to choose a composition with a long curing time.

Advantages and disadvantages of sand-concrete materials

When repairing the floor with their own hands, not everyone understands by what criteria it is necessary to choose mixtures for screeding. But experienced masters choose sand concrete due to the presence of such advantages:

1. Simplicity of solution preparation;
2. Long service life of screed;
3. Resistance to corrosive processes;
4. Resistance to temperature changes;
5. Good sound and heat insulating qualities;
6. High frost resistance.

Important! The quality of sand-concrete compounds is affected not only by the number of additional ingredients, but also by the brand of cement used. When choosing a material by yourself, it is worthwhile to know about the presence of several disadvantages of special screeds, namely:

• The price of sand-concrete mixtures is higher than conventional cement;
• If the mixing sequence of the components of the mixture is not respected, the technical characteristics of the rough floor can be significantly degraded;
• When diluting the solution with your own hands, without the presence of special instruments, it is difficult to trace the degree of its homogeneity.

Types of sand concrete

As already noted, sand concrete can be of several types and its technical parameters are more influenced by the cement brand. For the production of the material, cement of the following grades can be used:

• M150 - used for the implementation of masonry: the elimination of defects on the basis of, leveling the floor or laying of facing materials;
• M200 - suitable for fitting screeds in rooms;
• M300 - used for the preparation of concrete castings, arrangement of rough screed or foundation;
• M500 - the best of all of the above types of sand cement, which is suitable for most masonry works.

It should be noted that the price of M500 cement is quite high and therefore it is used extremely rarely in the process of laying the screed. But the M300 in terms of its physical and mechanical characteristics is not inferior to high-quality material, but it is much cheaper.

Features of sandblast M300

The cement-cement screed of the mixture, which includes cement M300, is used by the builders for the arrangement of the roughing base most often. Increased interest in the mortar is due to good technical parameters:

• High density of the prepared solution;
• Possibility to use the mixture for internal and external works;
• Resistant to rain and low temperatures;
• The ability of the composition to self-leveling;
• Fast setting of the screed at plus temperatures.

It should also be noted that the price of sand cement cement mortars M300 is low, so even a significant consumption of material does not contribute to large financial expenses.

Calculation of amount of mixture

Calculation of the required amount of sand concrete is carried out according to the following scheme:

1. First, the base area is calculated;
2. Then the degree of height difference per m 2 of the base is calculated;
3. After that, according to a certain formula, the consumption of the sand-cement composition is calculated.

• Let us assume that we need to pour a 30 m 2 base with a sand cement;
• The material consumption is mainly affected by the thickness of the screed, for example, it is 4 cm;
• When calculating the required number of sandbags, the specific consumption of the prepared mortar on m 2 of the coating with a layer thickness of 1 cm is seen on the package. Assume that it is approximately 20 kg;
• To calculate the amount of composition, we perform the following calculation: multiply the thickness of the layer by the specific flow rate: 4 * 20 = 80 kg;
• Now, in order to find out the amount of material for pouring the whole floor (30 m 2), multiply the result by the total area of ​​the base: 80 * 30 = 2400 kg.

So, the consumption of cement-sand mortar for the arrangement of floor area of ​​30 m 2 is 2400 kg. Now you need to determine the number of required bags of the mixture:

• As a rule, the building composition is packed in bags of 20, 30 or 50 kg. Suppose we need to buy a mixture in 30-kilogram bags;
• How many sacks are needed? Calculation is made in accordance with the formula: the total weight of the required amount of composition divided by the weight of one bag;
• Using a calculator, we make a simple calculation: 2400/30 = 80 bags.

Online calculator for payments

Since the mixture of sand concrete can contain various plasticizers and additives, they can significantly affect the consumption of the prepared composition. In order not to deal with laborious calculations, you can use the online calculator to quickly determine the required amount of material. Thanks to the clever program, no problem is determined not only by the consumption, but also by the price of the required amount of sand cement.

to curtail

A fairly frequent arrangement of screeds on the floor with foundation pouring is done by people who do not have a building education. It is very important to consider what will be equal to the consumption of cement on the screed. Correct calculation will save money, as the loss of materials should be minimal, plus the floor surface is laid in such a way that it can withstand all the loads. In cases where there is too little cement per m2, the screed will crumble, and if the materials are excessive, the financial costs will significantly increase, but the strength of the base will increase severalfold.

Characteristics

Use a mixture of cement and sand for an ideal leveling of the floor or other surfaces - the optimal solution for both budget savings and for convenient maintenance work at home. Calculation of the composition of the screed: ingredients and consistency, as well as the consumption of materials used per 1 m2 (cement, sand) should be carefully planned before the preparation of the mixture.

If the calculation is accurate, this will not only give the floor surface the highest possible strength, but also a long service life. When making inaccuracies in quantitative proportions per m2, cracks and chips may appear, after the screed of cement and sand has completely dried.

Carrying out floor measurements for further calculations

The correct calculation, which determines the cement consumption for the screed, primarily depends on the measurements of the floor and the records of the final results (per m2). The room in which it is planned, should be freed from unnecessary building materials and garbage. The surface of the floor, respectively - clean, dust free. The initial step in measuring the floor (unit of measure - m2) should be to determine the zero level - the mark anywhere in the room. Using a laser tool or a spirit level, all walls of the room are marked from the selected point.

All marks are connected by one straight line. The difference between these two parameters is the level of the difference in heights, which should not be more than 5 cm. At the highest point of the room from cement and sand, at the minimum level - not less than 0.8 cm. A mismatch will cause the floor surface to crack and crumble.

Calculation of cement per m2: formulas

The general formula of calculation, which would allow to determine with maximum accuracy and accuracy the consumption of mixture for sex on 1m2 for today does not exist. Each repair worker applies his own calculation system, which makes it possible to determine the required proportions of materials used for screeding, which has been tested by practice. If the premise in which the device of a coupler dwelling is planned, calculation it is better to carry out proceeding from a proportion - 1 to 3 (1 part of cement to 3 parts of sand). Cement brand is recommended to use, the amount of water for the solution is 0.5 liters. Excessive amounts of liquid can adversely affect the quality of the final mixture for the floor of the brand M200.

The consumption of cement-sand mixture for a particular room can be calculated as follows: the required volume is equal to the product of the quantities:

• the length of the room;
• thickness of the future coating;
• width of the room.

Arranging the screed of cement and sand to the value obtained (in m2) you need to add another 20%. This parameter indicates shrinkage when the solution cools. If you use ready-made products (pre-packed) for the screed, you should always read the instructions on the package. Usually the most accurate data and the calculation of the building material are indicated. In most cases, the estimated flow rate is equal to an interval of 14 to 21 kg per 1 m2 of space. These numbers are valid for a selected layer thickness of 1 cm.

With a layer thickness exceeding 1 cm, the calculation is made according to another scheme:

• the volume (the product of the length, width and thickness of the layer) is calculated;
• the volume value in the calculation is transferred to the expression obtained from the proportion: the required quantity of kilograms = the obtained volume multiplied by 490 (the number of kg in 1 cubic meter) and divided by 50 kg (the mass of a standard bag of cement-sand mixture).

It is very convenient to use the table of consumption of cement, taking into account its brands and solution:

Cement, brand	Mortar, brand
	25	50	75	100	150
200	190	320	440
300	320	220	310	380	500
400	440	170	240	300	400

As a result, it turns out that the construction cost is 9 bags of cement, that is 450 kg, as well as 1300 kg of sand. It is possible to impart a higher strength by adding a small amount of PVA-glue - from 4 to 19 liters per 1 cubic meter. m. It will serve as a plasticizer.

Nuances in calculating

Screed on the surface of the floor - this is a special solution, which includes sand, water, and cement, all of them must be in strictly defined proportions. The quantity and consumption of basic materials are directly proportional to the requirements that the final product must possess. Calculation of flow rates is very important to carry out correctly, as this directly affects the quality of the screed. The main calculation for the solution should be carried out only taking into account all the parameters for 1 m2 or m3, rather than the entire area of ​​the room.

When carrying out work, cement solutions of various grades can be used, it all depends on the surrounding conditions. A solution of M100 grade for the creation of a base of M400 cement consumes about 400 kg. If you convert to m2, you get about 45 - 50 kg - cement consumption - with a layer thickness of 10 mm. It is considered to be the traditional brand, the most popular in the construction of screed. Mark M200 - more reliable and durable - is used to level the base of the floor in warehouses or in garages.

When the screed hardens, as well as completely drying, the initial volume begins to unevenly decrease.

This can lead to strong detachment and considerable cracking of the substrate. In order to avoid this in the course of work, it is required to wet the room of cracking periodically with water at room temperature.

Separately, I would like to focus your attention on the choice of supplier of building materials. We categorically do not recommend buying cement from the contractor, so you will not know in what conditions it was stored, how much it was in the warehouse or the car.

Due to long storage, due to lack of storage conditions, cement can lose up to 15% of its activity per month. After all, his most dangerous enemies, moisture and carbonic acid, are in the atmosphere. The decline in activity inhibits the process of hydration of cement.

Here we should pay attention to the fact that the higher the initial activity, the faster it is lost. Let's consider an example. You bought cement brand 500. Two months stored in the warehouse. And he can already show the brand 400 ... Keep another six months .... And you just throw it away ...

Of course, a simple philistine can object, and if you store cement under ideal conditions: in moisture-proof packaging and dry premises. Alas, this process can not be completely stopped, you can only slow down. For this, the appropriate storage conditions for cement are necessary: ​​the type of storage, the humidity of the ambient air.

The ideal place of purchase is, since they take cement for orders, directly from the manufacturer's warehouse, and accordingly they do not deposit.

Retail chains have warehouses, and the chain, manufacturer-storage warehouse, - transportation to the warehouse of the retail network, again storage in the warehouse until the moment of sale, then again transportation, already to the seller, is already included.

The risks of getting a poor-quality product increase, 2 storage points, plus 2 transportation.

Buying an online store cuts off one link, cement is brought to you directly from the factory, unless the seller is a small intermediary, usually the role of the seller is performed by the contractor, offering turnkey work with their material.

The delivery is very well adjusted, and the cement is guaranteed to come fresh from the producer to the customer

in Moscow, Yekaterinburg, Perm, Surgut, Nizhny Tagil and Chelyabinsk.

Before we derive the necessary formulas for calculations and compare the obtained data with real materials, we consider it extremely important to clarify what the screed is. This is one of the most important and difficult stages in construction, as during this process, there is leveling of surfaces, such as the floor or foundation tapes under the masonry and so on. Depending on the quality of the screed, such will be the main work on construction and finishing.

But even if you have a huge experience in leveling the screed, its quality is also determined by the consistency of the mortar itself and the correct proportions of materials, as well as the proper cement consumption for the screed.

How to correctly calculate the consumption of cement?

Recall that one of the main materials and a binder for all other components of the screed is a solution. This is, first of all, a mixture that consists of sand, water and cement in certain proportions. It must also be taken into account that the number of components can vary, depending on the properties that builders wish to receive from the finished product, which will change the consumption of materials on the screed, and, accordingly, the calculations.

One of the main shortcomings that lead to a poor quality screed is a cement consumption that does not meet the standards, while manufacturing the flow. It is important to take into account that the required number of components for the screed is calculated per one cubic meter of the finished solution. Different mortar conditions are applied with solutions of different grades. The mortar grade is a clear definition of the strength of the future screed and it directly depends on the amount of cement in the mixture.

For example, the consumption of cement grade M400 per cubic meter of M150 for creating and laying the screed will be equal to 490 kilograms. If we take into account the square of the rooms, then literally one square meter will leave about 50 kilograms of cement M400 with a thickness of 1 cm.

This brand of screed solution is one of the most common, so you are sure to use this universal brand of mortar for screed. But often for premises of warehouses, garages and other non-residential premises, cement is used in mortar M200, which gives the screed greater strength and reliability.

Features of screed from cement mortar

Cement mortar for floor screed and other surfaces is particularly suitable for leveling the filled surfaces. After that, the floor covering is laid on the future floor covering. We distribute the mortar to be spread over the entire floor surface and, if necessary, create a slope or simply create an even substrate for the floor covering. The composition of the screed, or rather the components and their consistency, must be calculated before the solution is created to give the floor the necessary useful properties, and it is important to take into account those features that incorrect calculations can lead to cracks and punctures on the surface of the coating after complete drying.

With the curing and drying of the screed, its volume decreases, and this process is uneven and can occur both in area and in volume. This leads to the fact that the coupler cracks and flakes. To prevent this from happening, there are a few tricks. For example, wetting a lot of water screed in places where it begins to exfoliate.

Formulas for calculating the consumption of cement on the screed

But back to what was at the beginning of our article - the material consumption on the screed. Experienced builders have many formulas, thanks to which you can calculate the ideal proportions and, accordingly, get a screed without damage.

If the cement screed is made in a residential building, then the calculation takes place according to the formula 1 to 3, that is, 1 kg of M500 cement is 3 kg of sand and a half liter of water is added to the mixture. Thus, we get a solution of M200 grade.

In order to calculate how much solution is needed to create a screed in a certain room we use another formula - V = length width of the screed thickness (m³). And now we proceed to the main thing - the resulting number is added to the proportion:

1 m³ - 490kg

V m³-X (kg)

From it we find X (kg) = 490 V / 1 (kg).

Taking into account the peculiarity that the packaging of cement mixtures takes place only for 50 kilogram bags, the number under the "X" sign is divided by 50 and we get the necessary result.

Using these formulas, you can achieve the ideal consistency of the screed, and, accordingly, you have a great chance of making a perfectly flat floor. Further, everything will depend on your ability to level the grout and the correct laying of the floor covering. Best of luck with this!