Floor screed calculator - calculate the required amount of material. Screed calculation Consumption of cement floor screed per 1m2 calculator

When starting to repair or install a floor covering, there is often a need to level the surface and pour a screed, which will be the basis for the final finishing of the future floor. This important event must be carried out in full accordance with technology. It is important to know how to calculate the material for a screed without errors in order to avoid unnecessary costs.

Calculation of the required amount of materials

When installing a floor screed, it is easy to find out the material consumption.

Calculations are made in the following order:

Let's say you need to calculate a floor screed 5 centimeters thick for a surface whose area is 40 square meters. In this case, you will need 40x0.05 = 2 cubic meters of mixture.
Next, in accordance with the proportion 1:3, you can find out the required amount of cement and sand. In this example, there will be 0.5 cubic meters of cement and 1.5 cubic meters of sand.
True, it is not entirely convenient to calculate the amount of sand concrete for a screed in cubic meters, so they should be converted to kilograms. Since the average weight of a cube of cement is 1300 kilograms, we get: 0.5x1.3= 6.5 or 650 kilograms.

Using the above example of screed calculation, you can determine the amount of materials for each room by substituting the data into the formula. It should be remembered that during the preparation process the filling composition tends to decrease in volume. To find out how much mixture is needed for floor screed, you need to know that its cubic meter yields 0.69 cubic meters of solution. This means that you will have to adjust the amount of building materials.

Composition of screed solutions

Typically, the composition of the screed solution includes:

cement(M400 is most often used);
sand, from which debris, shells and pebbles are removed by sifting. It should not be wet before making the mixture;
plasticizer, improving the properties of the material;
supplements(mineral and polymer), giving the mixture various properties. So some of them speed up the hardening process, others help level the surface or facilitate finishing.

Mixtures in which gypsum is the binding agent rather than cement are also commercially available. This composition is distinguished by the fact that it dries faster, almost does not shrink, and is applied even in a thin layer. But gypsum also has a drawback - it is less resistant to moisture, so this composition is used exclusively for dry rooms, for example, living rooms.

Experts advise: when purchasing cement, carefully look at the production date of the product, since during long-term storage the material begins to absorb moisture, as a result of which the brand of the product is reduced.

Of course, purchasing a completely ready-made mixture is easier than making it yourself. In addition, thanks to information from manufacturers on the product packaging, you can easily understand what specific work the composition is intended for. At the same time, the cost of the finished mixture is much higher than that of cement.

Preparation of solutions for screed

The service life of the coating and its appearance depend on how well the solution for pouring the screed is prepared.

When the amount of mixture for floor screed has been calculated and building materials have been purchased, the preparation of the solution begins in the following sequence:

Dry components (cement, sand and, in some cases, fillers) are mixed in a special container. In this case, you should adhere to the required proportion, which is indicated on the manufacturer’s packaging. For example, cement grade M400 is mixed with purified sand in a ratio of 1:3 (more details: "").
In another container, the liquid components (plasticizer plus water) are mixed. Typically, 190 grams of plasticizer need to be added to a 50-kilogram bag of cement. As a result, the liquid should make up a third of the weight of the cement.
When all the ingredients (liquid and dry) are prepared, start mixing them. The mixture of dry materials is poured into the liquid gradually and thoroughly mixed until the mass becomes a homogeneous consistency without the slightest lumps.
To make it easier to prepare the solution, use power tools, such as a drill with an attachment or a special mixer, in which case the mixture will turn out better.

Stages of screed arrangement

When creating the base for the floor covering, the weight of the floor screed is of no small importance, depending on the condition of the interfloor covering. In old buildings with wooden joists, a concrete base is not currently laid.

Filling a screed, such as in the photo, is done in stages:

prepare the subfloor;
install beacons;
mix the solution;
pour the mixture.

Naturally, before starting work, you should correctly calculate the dry mixture for floor screed.

Preparatory process

In preparation for pouring the screed:

cracks and chips are eliminated on the surface of the base;
remove dust and debris;
apply a primer, which is selected depending on the type of surface.

Fixing beacons for screeds

Lighthouses are placed in one horizontal plane of the floor. Such beacons for leveling the floor are special landmarks made of guide rails. It is along them that the filling process is carried out as a rule and thus a smooth and even surface is obtained.

The installation of beacons should be done carefully and accurately, since the horizontalness of the base for finishing depends on this. The guides can be made from a special aluminum profile.

The beacons are mounted in a certain sequence:

The zero level is determined, usually it is 5 centimeters above the highest point of the surface of the rough foundation.
At a distance of 30-40 centimeters from the walls, draw a line, at the ends of which holes are drilled using a hammer drill, choppers are placed in them and screws are screwed in so that their heads are at the zero level.
Then a profile is placed on the caps and a rule is applied to it. If necessary, adjust the height of the screws to achieve a horizontal profile.
A strong position of the beacons is ensured using a small amount of gypsum mixture. The gaps between the landmarks should not exceed the length of the building rule plus a 10-20-centimeter margin on each of its sides.
After completing the fixation of all beacons, use a level to once again check the horizontalness of the base surface in all directions.

Pouring floor screed

In recent years, sand concrete has been used to prepare the solution. It is a mixture of Portland cement, various additives (mineral and natural) and sand.

After you have calculated how many bags of sand concrete are needed to screed the floor and prepared the solution, as well as installed the beacons, you need to immediately start pouring.

The mixture is laid out in strips, focusing on the guides. Using smooth movements, they usually follow the slats towards themselves, moving from the wall opposite the entrance.

After the solution has set, the beacons are dismantled, and the strips from them are sealed with the solution and leveled with a spatula. The presence of protrusions or depressions is indicated by light spots that appear on the surface of the cement screed, which are removed with a solution and a rule.

The concrete base must dry well. It is necessary to understand how long it takes for a floor screed to dry so as not to spoil the work done. During the first 10 days, its surface should be moistened with water to prevent cracks from occurring.

Arrangement of dry screed

This technology differs in many ways from traditional concrete screed, since it does not require the use of cement and so-called “wet” work.

To equip a dry screed, you will need the following building materials:

waterproofing;
thermal insulation, for example, polystyrene foam boards;
bulk (fine slag, expanded clay, sand);
slabs (chipboard, moisture-resistant GVP, asbestos-cement).

Before starting work, you need to make a calculation of the bags for the screed and the other materials listed above.

Creating a dry screed is carried out in stages:

Laying a layer of waterproofing and thermal insulation.
Filling of bulk materials and their compaction.
Installation of slabs.

The costs of installing a dry screed depend on the type of materials used. It is laid only in dry rooms.

We present to your attention an online floor screed calculator, this program is indispensable for builders, especially those who prefer to do everything themselves. Perhaps for a master who does similar work every day, it won’t be difficult to calculate on a piece of paper how much sand, cement mixture and water is required to form the required amount of mortar. But most often, in order to calculate the cement for the screed, even a professional will need to look at the reference book. Our online calculator allows you to quickly and with maximum accuracy determine the required amount of building material and save money even at the planning stage.

Calculation of floor screed taking into account differences

You need to measure the difference in each corner of the room in relation to the top point “0”;
The calculator will calculate and display the required value.
The cost savings are obvious...

More details about the screed:

A screed is a layer of floor covering (most often a cement-sand mortar) that serves to level the surface and impart rigidity. The screed can be either reinforced or without a reinforcing frame, depending on its thickness and the load, which will subsequently be distributed to the floor covering.

The usual (standard) composition of the screed is a cement-sand mixture, in other words, it is cement mixed with sand and water in certain proportions. Not many people know that if you mix the solution without observing the required proportions, this can lead to dire consequences, for example, if you significantly reduce the amount of sand, the screed will become very fragile and this will lead to it starting to crumble and peel off.

In order to avoid such consequences, we have developed a calculator for floor screed. Using the data obtained, you can easily independently calculate the required building material, mix the mixture and perform installation.

What brand of mortar should I choose for the screed?

There are different screeds: leveling, for heated floors, for garages, for basements, etc. Of course, the leveling screed cannot be made from the same mortar as the garage screed, since the loads are different. But in order not to complicate things, you can resort to generally accepted rules:

The brand for all ties must be M 100-200, for garages and rooms with large “pressure loads” M 200-300. The table shows the ratio of cement and sand in the screed mortar, converted into volume for convenience. In other words, 1 bucket of cement/3 buckets of sand is a universal recipe for a good mortar

This online calculator is designed to calculate not only the cement-sand mixture. If you plan to use a ready-made mixture, using this program, you can determine in advance the amount you will spend on installation. This will allow you to account for all costs up front.

Sometimes, in order to perform a complete calculation of a floor screed, it is necessary to take into account not only the mixture, but also the reinforcement frame. Most often, a ready-made mesh is used for reinforcement in a screed. And not everyone knows the rules of its construction, the required diameter and overlap. This online calculator allows you to calculate the number of reinforcing mesh you need. This will also allow you to take into account the additional costs of installing a floor screed at the planning stage.

Carrying out finishing and repair activities begins with preparing the workplace, drawing up a work plan and making the necessary calculations. The calculator provided on this page will help you calculate the components of the cement mortar according to the given parameters.

Calculations on the calculator for the components of the mortar used for screeding and leveling the floor are carried out according to the standard formula - 1: 3.5, where 1 part is cement, 3.5 parts are fine-grained sand.

This value for the mass fraction of sand is taken on the basis of the average value between the classical proportions - 1: 3 and 1: 4. That is, for most types of work performed in suburban and private construction, these proportions and values are quite sufficient, without taking into account additives, plasticizers and reinforcing substances.

M500 cement and river fine-grained sand with a bulk density of 1630 kg/m3 were taken as the starting materials used in the calculator formula. This grade of cement is sufficient to produce a mortar (depending on the VC) of grade M200 or M300, which is most often used for pouring screeds in residential premises.

Basic materials for preparing a quality mixture

To perform calculations on the calculator, you will need to enter the length and width of the room, the thickness of the screed, the desired water-cement ratio and select the presence or absence of reinforcing materials.

When entering the thickness of the screed, it is advisable to take into account that only the thickness of the leveling layer is available for input, which does not include the depth and volume of potholes, sinkholes and chips. That is, for heavily damaged concrete foundations, you should, first of all, take care of the restoration and correction of the foundation, and only then carry out work aimed at pouring the screed.

The water-cement ratio shows how much or volume of water will be used to mix the mortar. It should be understood that solutions with low water content are difficult to distribute and may contain dry parts of sand or lumps of cement.

Permissible and minimum screed thickness

When entering data into the cement floor screed calculator forms, you will notice that the minimum value for the thickness of the screed or leveling layer should be at least 30-35 mm.

According to building codes and regulations, in residential buildings, it is not advisable to reduce the thickness of the fill, as this can lead to emergency situations and a reduction in the service life of the leveling layer.

In many ways, the choice of minimum thickness is individual and depends on what kind of coating it is poured on and what its technical condition is, what components are used to obtain the solution, whether reinforcement is used and what are the requirements for the future coating.

For example, when insulating the floor on a balcony using polystyrene foam, it is recommended to fill in a leveling layer of at least 4-5 cm. To eliminate a height difference of 15 mm in a living room, a 30-35 mm layer above the highest point in the room is sufficient.

To install an insulating layer when installing heated water floor systems, the minimum value is taken to be 30 mm above the surface of the heating elements.

The maximum permissible thickness of the cement screed is 10-12 mm. In the floor screed calculator, this value is limited to 30 cm. When installing a leveling layer more than 12-15 cm thick, it is recommended to use sand concrete. For fills with a thickness of more than 15-20 cm, it is desirable to add expanded clay with different fraction sizes.

When installing cement screeds, you should understand that pouring cement mortar is only advisable when leveling a floor with height differences or damage depths of more than 20 mm. In other cases, you can use special leveling mixtures designed to eliminate small differences.

The influence of the water-cement ratio on the quality of the mixture

If the proportions of water and cement are observed, the composition has good plasticity and is easily distributed

The water-cement ratio is one of the most important characteristics that determines the quality and performance characteristics of the mixture after its hydration.

The most important qualities that are directly dependent on the VC are the strength and impermeability of concrete. The first affects the scope and service life of concrete after hydration. The second determines the speed and degree of moisture penetration through the capillaries of concrete after it has completely dried.

Regarding the cement screed, for its digestible appearance, a water-cement ratio of at least 0.3 is taken, which means that to prepare the solution, an amount of water will be taken equal to 30% of the mass of the cement taken.

In the online floor screed calculator, the minimum VC coefficient is 0.30, and the maximum is 0.70. Reducing the amount of water will lead to the fact that such a mixture will be problematic to distribute over the surface, which can lead to poor filling of the volume, the formation of voids and failures.

Increasing the value will lead to a decrease in the grade and class of the resulting mixture, which will directly affect its strength.

Nuances of choosing materials for screed

Ready-made dry mixtures consist of sifted sand and cement of a certain brand

The brand, strength class, porosity and other important characteristics of the mixture directly depend on the quality of the selected components and the technological aspect of preparing the screed.

When purchasing components, you should not rely entirely on the data obtained by the online calculator - these are indicative indicators that do not include unforeseen costs, errors and damage to the material.

When choosing and purchasing components for cement screed, you should focus on the following:

cement is a fundamental component that determines the strength and density of the screed. To obtain a solution of a higher grade and strength class, cement of a higher grade should be used. When purchasing, you should pay attention to the release date of the batch, since caked, wet or old cement will certainly affect the quality of the mixture only for the worse;
sand – for work in private construction, it is desirable to use fine-grained river sand with a fraction size of no more than 2 mm. For rough or primary leveling, you can use a mixture with a fraction of up to 2.5-3 mm. It is desirable to use sand without foreign impurities in the form of foreign objects, clay, silt, pieces of crushed stone;
water – along with plasticizers, is the main binder. The water must be clean, without including earth, silt, or clay. It is unacceptable to use process water, which may contain fatty substances, petroleum products, etc.

Otherwise, the selection and purchase of components for the mixture is no different from the purchase of other types of building materials and is based on the quality and price of the product.

Materials for reinforcing floor screeds

Screed reinforcement is an increase in the load-bearing characteristics of the cement layer by using materials of increased strength. The traditional material for reinforcing cement screeds is steel reinforcement bars, which are “knitted together” to form a strength frame.

Fiber fiber is a direct alternative to classic reinforcement

The only disadvantage of using traditional reinforcement is the large weight of the finished structure.

For private construction and work carried out in apartments, the use of reinforcement is irrational, since the leveling layer does not have the capabilities of constructing an already massive structure. Instead of reinforcing bars, it is customary to use a metal mesh with 10x10 cm cells or fiberglass.

When entering data into the forms of the screed mortar component calculator, you can choose one of two materials for reinforcement.

The main difference between steel mesh and reinforcing fiber is the impact with cement mortar. That is, the steel mesh provides sufficient strength of the leveling layer only after the mixture is completely hydrated.

Fiber fiber more actively adheres to the particles of the solution and protects the leveling layer from cracking, the formation of voids and other possible problems that can be caused by external factors, already during the process of drying and evaporation of moisture.

From a practical point of view, if the technology of adding and mixing microfiber into the mixture is followed, its use is more preferable, since it fills the entire volume of the solution and practically does not exert additional load on the base.

In order to level the floor as best as possible, use. And some kind of floor covering is applied on top of it. To avoid excess consumption of material, it is necessary to make certain calculations that will help save a lot of money. But not many people know how to calculate a floor screed.

Solution distribution

In order for the calculation to be correct, it is necessary to take into account all the features of the screed, so we will consider them. The solution with which the rough layer will be poured must be distributed over the entire surface of the room in such a way that it is ideal. After all, the base is often made not only with defects, but also at the wrong angle.

Here you need to know that after the solution has completely dried, its volume can decrease significantly. And also unpleasant surprises may arise in the form of uneven drying. This can cause the floor to crack and begin to peel off. But this process can be changed. To do this, many professionals generously moisten the damaged areas with water.

For use, the thickness should be 40 mm, for use - 50 mm, and for water - from 70 to 100 mm. So take this factor into account when making calculations.

Based on the rules of SNiP, the minimum height of the filling solution should be 40 mm, but those that do not require increased heat, for example, a pantry, hallway and the like. In these rooms, you can reduce the height of the base to 30 mm, but not lower, otherwise the strength and durability will leave much to be desired.

Video: DIY floor screed installation

If you want to increase, then you will need to fill twice. The first layer is 20 mm, the second - more than 20. Insulation or material that promotes sound insulation is placed between such a screed, and a special film is placed on top of them.

Compound

The components and consistency of the solution should also be calculated in advance. The composition includes not only cement, water and sand, but also various additives that perform specific functions. Although most often they are used to reduce the cost of expensive cement.

For example, polystyrene in granules or expanded clay, which also has insulating properties, can be added to the solution. Whatever filler you choose, always expect a 50% to 50% filler to cement percentage. Only in relation to cement, and not to other components of the solution.

Level determination

First of all, in order to screed the floor, it is necessary to set the zero level. An ordinary water or laser device will help with this: a level. You will need to move it around the perimeter of the room, while fixing it with marks, which you will subsequently need to connect with lines. This is how the horizontal plane is revealed.

From the line, that is, the same zero level, measure the distance. Write down all the indicators and determine the maximum height. So, the smallest value will mean the highest point and, accordingly, vice versa.

Based on these data, you must calculate the height of the screed. For example, the highest height is 1 cm, and the lowest is 0.7, which means the difference between them (1-0.7 = 0.3) will be the average thickness that needs to be taken into account. The layer will be 3 cm, which means 3+0.3=3.3. In total, you buy the mixture at the rate of 3.3 cm per width.

How to calculate the amount of sweep for a floor screed

Each package of the finished mixture must indicate the average consumption, which should be used as a guide. Let's say you need to fill 20 mm of base for the entire volume, the consumption is 2 kg/m² with a thickness of 1 mm. It follows from this that you need to multiply 20 by 2, it turns out 40 kg per 1 m². Next, we calculate the amount of mixture per room area: 40 × 20 (area) = 800 kg. Typically, dry mixtures are packaged in bags of 50 or 25 kg, so we divide 800 by 50 (25) and get 16 (32) bags.

Consumption

Method one

In fact, it is not at all complicated and to implement it you need to adhere to certain formulas. For example, you need to make a screed in a room of 20 m², and the base should have a thickness of 25 mm. You need 20×0.25=0.5m³ of solution.

Since cement is mixed with sand in a ratio of 1:3, we can calculate the amount of each. To do this, we divide 0.5 by 4, we get 0.125, which we multiply by 3. As a result, it turns out that we need 0.125 cubic meters of cement and 0.375 cubic meters of sand.

If you are confused by the formula in cubic meters, you can convert it to kilograms. Knowing that 1 m³ of cement is equal to 1300 kg, we get the following result: 0.125×1300 = 162.5 kg of cement.

Now you know how to make the calculations correctly, just keep in mind that when the solution is diluted and when it dries, it decreases slightly in volume, so buy the material with a small margin.

Method two

There is another calculation method. To do this, you need to calculate the amount of dry cement mixture. In general, the average density of cement screed is 1800 kg/m³, so if you don’t need to add fillers, then calculating this is as easy as shelling pears.

The area of the room must be multiplied by the thickness of the layer. Then, when the volume is determined, calculate the required dry weight of the solution.

If you add filler, then subtract the amount of additive from the total volume, and then convert it to dry weight.

If there are differences

In the modern world, many people use different ones in one room, and in this case it is worth thinking about ensuring that there are not too large differences when laying them. Therefore, it is very important to calculate where the joints will be so that the floor is on the same level. After all, you must agree that the thickness of tiles differs from laminate, linoleum, and so on.

In order to avoid this, you need to correctly calculate the floor screed. Let's say you use mastic, glue, plywood and parquet, but for ceramic tiles, all you need is glue and the tile itself. That is, the thickness is completely different.

We do the calculation in the following way:

Parquet - 15 mm, glue - 1 mm, plywood - 10 mm and mastic - 2 mm. In total, it turns out to be 28 mm.
The tile is 10 mm and the adhesive is 5 mm. This is equal to 15 mm.
Further, 28-15 = 13 mm, which means that at the junction of two materials the difference should be 13 mm.

Experts with extensive experience in this matter still advise adding a couple more millimeters, since practice shows that during the process, it may rise a little. If this happens, you can level the tiles.

One of the main types of construction and repair work is cement screeds, which can serve different purposes and are structurally very different from each other.

But for all of them, the main main parameter is the consumption of cement for the screed.

Scheme of a cement floor screed: 1 - Base, 2 - Sand layer, 3-4 - Layers, 5 - Concrete screed, 6 - Tile adhesive, 7 - Tiles, 8 - Separating edge layer.

Main functions and types of screeds

Let's start by looking at the main functions of the screed

leveling the surface for flooring (parquet, linoleum, laminate);
improving the heat and sound insulation properties of the floor: absorption of household, impact, air noise and insulation of floors;
concealment of pipelines and utilities;
distribution of heat energy in floors with built-in heating;
giving coatings a given slope.

by design: single-layer (one layer for the entire thickness) and multi-layer (includes heat-, hydro- and sound-proofing layers);
by composition: cement-sand, concrete, self-leveling synthetic resins and mosaic (on top of a concrete screed), gypsum;
according to the method of fastening to the ceiling: bonded screeds (directly bonded to the base), on a separating layer (additional waterproofing layer) and “floating” (laid on top of heat and sound insulating material).

In each of these types, the consumption varies depending on the selected brand of binding material, its quantity per unit of solution, and the technology for preparing the mixture. Failure to comply with certain regulatory rules and instructions in these matters can lead to delamination of the mixture, cracks on the surface, large pieces of screed falling out and the formation of voids.

Calculation algorithm

According to construction rules, kilograms of screed are produced per cubic m (1m3) of mortar. Sometimes it is more convenient to calculate the amount of binding material per cubic meter of sand. To calculate the total amount of the mixture, you need to know the total need for the solution (in cubic meters) for the working surface. Let's look at the screed using examples.

1 m3 of solution. Single-layer cement-sand screed. Recommended brand of mortar M200 (cement/sand ratio 1:3);
for 1 m3 of M200 mixture, according to the standard (see table), 410 kg of M500 cement is required;
let the surface area be 12 m2, and the thickness of the screed be 30 mm. Calculation of the volume of the solution (multiply the surface area by the thickness): 12 * 0.03 = 0.36 m3;
cement consumption: 410 * 0.36 = 147.6 kg, or 3 bags of 50 kg (regular packaging). This quantity is one part;
calculation of sand and water. To obtain the finished mixture, add 3 parts of sand (3 * 147.6 = 442.8 kg - 9 50 kg bags) and 0.5 parts of water (147.6 * 0.2 = 73.8 l - 7.5 buckets) ;

Add water to the well-mixed dry mixture in small portions, constantly stirring the solution with a trowel, spatula or shovel. So, for a room with an area of 12 m2 and a screed 3 cm thick, we will need 3 bags of M500 cement, 9 bags of sand and 7.5 buckets of water. Cement standards for various brands of mortar can always be found either in the instructions supplied with the cement on the packaging or bags upon purchase, or on the Internet pages in the codes of practice of the joint venture “Preparation and use of mortars” (see table).

When using concrete, fillers are added to the known components cement, sand, water: crushed stone, gravel or lime paste in various proportions and the calculation is made according to the specified algorithm.

Note that to improve waterproofing, sand and cement for screeds are used together with bitumen paper, roofing felt or polyethylene film (no more than 300 microns thick). Increased strength is provided by cement for screeds, laid on a reinforcing mesh with cells of 100 * 100 and 150 * 150 mm, and good soundproofing properties are provided by materials: mineral wool, foam plastic, polystyrene, polyurethane, laid first on the base of the floor.