Consumption of concrete mortar for floor screed – how to correctly calculate the amount?

For any construction project, figuring out how much concrete mortar is needed for a floor screed is essential. It guarantees that you have adequate supplies to finish the task without wasting any extra. The foundation layer of flooring is made of concrete mortar, which offers a level surface on which tiles, carpets, or other floor coverings can be installed. Knowing what you need to cover is the first step towards doing calculations correctly.

Measure the floor space’s length and width in meters to get started. To determine the total area in square meters, multiply these dimensions. An area of 20 square meters, for example, would be a room that is 5 by 4 meters. The basis for figuring out how much concrete mortar you’ll need is this easy calculation.

Next, think about how thick you want to apply the screed. Generally, the thickness of floor screeds varies based on the project specifications. Standard thicknesses are between 25 and 40 mm, however for certain uses, thicker applications might be required. Once the thickness has been determined, multiply the thickness by the entire area to get the required volume of concrete mortar in cubic meters.

When estimating your needs, it’s critical to take waste and uneven surfaces into consideration. To account for these factors, it’s generally recommended to add 10% to 20% to your calculated volume. This guarantees that you have adequate mortar to cover unforeseen variations in surface level and permits small adjustments to be made while applying the mortar.

It is advisable to speak with your supplier about the kind of concrete mortar that will work best for your project before making a purchase. Various mortar compositions and strengths are available based on the intended application and load-bearing specifications. By being aware of these variables, you can choose the ideal mortar mixture to produce a stable and long-lasting floor screed.

Accurately estimating the amount of concrete mortar needed for your floor screed not only reduces waste but also assures the longevity and structural soundness of your flooring. Even though it’s a simple procedure, floor screeding preparation is an essential part of any building or remodeling project.

Why do you need to calculate the DSP??

To attain the following outcomes, the amount of concrete mixture needed to mix floor screed in an apartment, private residential building, office, public building, or industrial building must be calculated:

• Determining the exact amount of the main components of concrete – cement, sand, plasticizers and water for pouring into the structure.
• Drawing up estimates for agreement with the customer.
• Use of cost overruns when an error is discovered in the specification for the working design transferred from the customer or architect.
• Possibility to place the purchase of all necessary materials in one purchase order at a single point of sale or on the construction market.
• Calculation of the cost of construction and installation work for laying this material in a screed after preparation.
• The ability to organize the delivery of all components in one trip, which significantly reduces the cost of product logistics.
• In some cases, transfer of information to the designer in the form of technical specifications to determine the payloads on the floor slabs when drawing up a design diagram.

After the screed is installed, if the property owner or a professional finisher makes a calculation error, there might be extra material left over, or vice versa. In this case, the investor would need to purchase more cement, sand, or plasticizers, which would result in exorbitant material costs and the need to schedule repeated delivery.

What tools and equipment will be needed for counting??

In order to determine the quantity of concrete needed for mixing and applying floor screed in different types of rooms, you’ll need to assemble the following tools and supplies:

• Laser level for determining the required stitch height and size of defects on the floor slab.
• Laser rangefinder for precise calculation of the linear dimensions of the room.
• A regular construction tape measure with a steel blade for measuring protrusions and niches in the walls.
• A calculator for performing arithmetic operations.
• Scales for determining the mass of the initial substance of each ingredient, and comparing this value with the volume to obtain the density.
• Marker for applying marks on the walls.
• A bubble level with a length of at least 2000–3000 mm for checking the height of floor defects, as well as the curvature of the wall, which will allow you to calculate the error in the calculations.
• A notebook and pen for recording intermediate calculation results.
• If necessary, a simple pencil for sketching the space of a complex room for the purpose of subsequently dividing it into elementary geometric figures.

It should be mentioned that every tool needs to be of the highest caliber, purchased from reliable suppliers, kept in excellent shape, dust- and dirt-free, and ready for use.

Step-by-step instructions with examples and formulas

Using the following algorithm, you can accurately determine how much main and auxiliary material is needed for a concrete floor screed:

1. Calculate the linear dimensions of the room using a laser tape measure.
2. The thickness of the future screed is determined from the project.
3. Linear dimensions are multiplied to obtain the area of ​​the room.
4. The area is multiplied by the height of the screed in the room to get the volume of the mixture.
5. Additionally, the quality of the floor slab is examined, average chip depths are calculated, as well as the height of protrusions and sagging.
6. The obtained indicators, based on the results of defect diagnostics, are divided into 2.
7. The value is also multiplied by the area to obtain the additional volume of concrete.
8. The resulting volume is divided by the density of the screed material.
9. Knowing the proportions of all ingredients in concrete or sand-cement mixture, the user can easily find the mass of each of them.
10. At the final stage, the resulting mass is divided by the amount of substance in a bag or other packaging container to obtain the final number of product units for placing an order or for drawing up a detailed estimate.
11. It should also be taken into account that when mixing the mixture, dosing the material, or when laying it and subsequent shrinkage during hardening, part of the concrete is consumed, which requires the use of a safety factor, which ranges from 7% to 10%.
12. If the work is carried out according to the project, after independent calculations, you should check the data with the specification and estimate documents, and then, in case of discrepancies, raise the issue of adjusting the drawings.

Every enclosed space should have its own calculation if multiple rooms have different thicknesses of screeds finished to meet structural or space-planning requirements.

How many cubes of concrete are needed per 1 m2?

The following provides a detailed explanation of how to calculate the amount of concrete and its constituent parts needed to install a screed in a standard living room measuring 6 by 3 meters with a rough floor structure thickness of 70 mm. This is based on the step-by-step instructions provided above.

1. The area of ​​the room is S = axb = 6 mx3 m = 18 m 2 .
2. The average height of slab defects according to SNiP is 5 mm.
3. In total, the height difference between depressions, chips, shells and protrusions is 10–12 mm.
4. Thus, the average height of the additional layer of screed, taking into account defects, is 6 mm (total value T = t/2 = 12 / 2).
5. The screed volume V is calculated, which is equal to (t (screed thickness) + T (total height of defects))xS. V = (T + t)xS = (0.006 m + 0.1 m)x18 m 2 = 0.106×18 = 1.908 m 3 .
6. Considering that water completely evaporates into the atmosphere when the screed hardens, and during the process of mixing the substance, it is added according to consistency, this ingredient is not involved in calculating the amount of concrete.
7. When mixing a high-strength screed, which contains both fine and coarse aggregate, add 30% Portland cement, 55% sand, and 15% fine crushed stone with a granulometric composition of 5–10 mm.
8. Thus, this screed contains the main ingredients in the following quantities:
9. Portland cement – ​​1.908 / 100×35 = 0.668 m 3 .
10. Medium grain sand, quartz – 1.908 / 100×55 = 1.049 m 3 .
11. Fine crushed stone, on granite – 1.908 / 100×15 = 0.286 m 3 .
12. Next, according to the table from GOST, the average density of each ingredient is determined:
13. Cement – ​​1200–1400 kg/m3 .
14. Sand – 1500–1600 kg/m3 .
15. Crushed stone (in a loose state) – 1400–1500 kg/m 3 .
16. Thus, the mass of each ingredient required for screeding in the room is the following:
17. Cement – ​​M = 0.668×1400 = 935.2 kg.
18. Sand – M = 1.049×1600 = 1678.4 kg.
19. Crushed stone – M = 0.286×1500 = 429.0 kg.
20. Taking into account the safety factor, which is 10%, each of these values ​​has the following final value:
21. Cement – ​​M = 935.2×1.1 = ~ 1030 kg.
22. Sand – M = 1678.4×1.1 = ~ 1850 kg.
23. Crushed stone – M = 429.0×1.1 = ~475 kg.
24. Considering that sand and crushed stone are supplied by weight, by truck, cement usually has to be purchased in bags weighing 50 kg. Thus, for the room considered in the example, the owner needs to buy 1030 / 50 = 21 bags of cement to mix the required volume of concrete for the screed.

The floor is typically divided into sections if the room has radius walls or bay windows. Next, using the common geometric formulas for triangles, circles, semicircles, trapezoids, and other shapes, the area of each of them should be computed.

Possible errors and difficulties

The owner of an apartment or private home may run into a number of challenges when independently calculating the cubic capacity of concrete and the mass of the primary ingredients for installing a floor screed, which will have a detrimental outcome:

• Incorrect calculation of room area.
• Neglecting the curvature of walls or floors, floor slabs.
• Using low-precision metrological equipment instead of a laser range finder.
• Errors in determining the thickness of the screed.
• Errors in calculating the proportions of cement and sand in concrete.
• Accounting for water in the total volume, since it evaporates during hardening and cannot take part in the calculation.
• Recalculation of the number of bags of cement based on volume rather than mass.
• Incorrect use of the formulas above.
• Incorrect calculation of the density of basic and auxiliary materials.
• Neglecting safety factors.
• Neglecting to take into account niches in the walls, as well as pilasters, columns and other local structures that affect the floor area and screed volume.

To prevent such errors, it is advised that you familiarize yourself with master classes and video lessons from experts who frequently share their experience with other open access users before beginning any analytical or fainting work.

Their consequences

If the aforementioned advice is disregarded and computation errors are accepted, the property owner may experience the following issues:

• Incorrect calculation of the amount of basic ingredients for concrete before screeding.
• Formation of a large amount of residues after screeding.
• Insufficient amount of materials, which requires their purchase.
• The need to complete a small retail purchase, which increases the cost of screed materials
• The need to re-pay for the delivery of cement or inert materials to the site.
• Incorrect calculation of the estimate, which may result in an erroneous amount in the contract and, as a result, loss of profit or overspending of the investor’s funds.
• Impossibility of preparing a concrete mixture in accordance with the selected recipe.
• Violation of the quality of the result when adding excess material of one category and lack of another ingredient.
• Changes in physical-mechanical and space-planning design parameters due to a decrease or increase in the thickness of the cement floor screed in the room.

It should be mentioned that mistakes can compound when doing maintenance and finishing work in structures with a lot of rooms. This results in large material losses, which raises labor costs and creates unanticipated expenses and schedule disruptions. It also necessitates multiple material purchases.

Precisely estimating the quantity of concrete mortar required for floor screed in the realm of building and remodeling is essential for productivity and economy. The purpose of this article is to demystify the process by outlining precise instructions on how to determine the appropriate amount of concrete mortar. Acquiring proficiency in this computation guarantees more efficient project management, reduces material waste, and maximizes financial resources. It involves comprehending surface area measurements as well as accounting for depth needs and waste.

Useful video

How to figure out how much mixture to use for floor screed:

The proper calculation of concrete mortar quantity for a floor screed is an essential task for any building or remodeling project. It guarantees that you have just the right amount of material, saving you money and effort. First, precisely measure the floor’s area, accounting for any deviations or irregularities. The basis for your computations is this first step.

Next, think about the screed’s desired thickness. A thinner layer or one that is thicker will depend on the particular needs of your project. This thickness has a direct impact on the amount of concrete mortar required. Knowing this guarantees that the screed will be strong and adhere to structural specifications.

Determine the volume of the screed after determining its area and thickness. Multiplying the area by the thickness is required here. Don’t forget to allow for any extra depth required to fit insulation, pipes, or other fixtures. Here, precision helps to avoid underestimating the quantity of concrete required, which can cause delays or rework.

Once the volume has been determined, add the concrete mortar mix ratio. Cement, sand, and aggregate ratios may vary depending on the project. Seek advice from experts or trustworthy sources to ascertain the right combination for your particular use. This guarantees that the screed will be strong and long-lasting, meeting the needs of your project.

Finally, order a little bit more concrete mortar than you anticipated in order to account for variations in mixing and pouring or unanticipated waste. It is preferable to have extra than to experience delays because of insufficient supplies. In addition to saving money, accurate planning and calculation facilitate a more seamless building process overall.

Video on the topic

floor screed calculator