The simplest and in an accessible way execution rough coating For a room of any purpose, it is necessary to install a concrete floor on the ground. Although the procedure does not require special skills, the quality of the final floor directly depends on compliance with certain technical aspects associated with its arrangement. We will discuss below how to make a concrete floor on the ground and how to pour a concrete floor on the ground.
Characteristics and components of a concrete floor on the ground
When installing any floor on the ground, the main thing is to ensure high-quality thermal insulation. It is precisely because of its installation that in the end it is possible to obtain a multi-layer floor, called a pie.
The production of floors on the ground directly depends on the type of soil and its characteristics. The first and most important requirement for the soil is the level at which groundwater is located, which should be at least 500-600 cm from the surface. In this way, it will be possible to avoid movement and heaving of the soil, which will be reflected on the floor. In addition, the soil should not be loose.
For more high-quality execution All work should determine the requirements for installing thermal insulation, which are as follows:
- prevention of heat loss;
- intrusion protection groundwater;
- providing sound insulation;
- prevention of vaporization;
- ensuring a comfortable and healthy indoor microclimate.
A warm concrete floor on the ground contains the following components and stages of work:
1. Cleaning the soil from the top layer. In addition, the surface is carefully leveled.
3. Then a bed of gravel or crushed stone is installed on the sand. It is this area that prevents the rise of groundwater, in addition, it additionally levels the surface. The thickness of the filler layer is about eight centimeters.
4. The next layer is the use of reinforced steel mesh. It is an excellent fixer for concrete bases. In addition, it is a place for fixation metal pipes. Reinforced mesh It is not used in all cases, but only when additional strengthening is necessary.
5. The next layer is more than 5 cm thick and is the subfloor. Concrete solution is used for its arrangement. After it gains strength within 2-3 weeks, the next layer of “pie” is installed on the surface.
6. This layer contains a special membrane or waterproofing film, which prevents the risk of absorbing excess liquid concrete base. The film is laid with an overlap; to avoid the appearance of cracks, construction tape is used to seal all joint areas.
7. Next stage- installation of insulation, which is recommended to use foamed polystyrene foam or high-density polystyrene coated with foil. If there is too much load on the floor, it is better to use insulation in the form of slabs.
8. Next, waterproofing or roofing felt is installed. After which the construction of the true screed is carried out. This is where the final finishing coat will be installed. The thickness of this layer is from 8 to 11 cm. This screed requires mandatory reinforcement.
Concrete floor in a house on the ground: advantages and disadvantages of arrangement
Among the advantages of making a concrete floor on the ground are:
- security reliable protection bases from the effects of low temperatures, the soil on which the floor is installed always differs only in temperature above zero;
- a variety of thermal insulation materials for floor insulation allows you to build a structure with good performance preventing heat loss;
- the resulting floor is finished with any of the existing floor coverings;
- no special calculations are required for the floor, since the entire load is taken by the ground covering;
- installing heated floors perfectly heats the room; in addition, they heat up quickly enough, and the heat is distributed evenly throughout the room;
- heated floors on the ground have good sound insulation characteristics;
- In addition, mold and dampness practically do not form on such a floor.
Among the disadvantages of a rough concrete floor on the ground are:
- when using a multi-layer floor, the height of the rooms is significantly reduced;
- if problems occur, dismantling work will require a lot of material resources;
- arranging a floor on the ground requires a large investment of material, physical and time resources;
- If the groundwater is too high or the soil is very loose, it is not possible to install such a floor.
Construction of a concrete floor on the ground: selection of materials
As mentioned earlier, to install a concrete floor on the ground you will need to build multilayer construction. It is recommended to use as the first layer river sand, then crushed stone or expanded clay.
After their installation, the rough screed is installed, waterproofing film and thermal insulation. Next, a finishing screed is installed, which is the basis for laying finishing materials.
The main function of sand and crushed stone is to protect the room from moisture penetration. When using crushed stone, it must be thoroughly compacted, and the crushed stone must be treated with bitumen.
If the soil is too wet, the use of expanded clay is unacceptable. Because it absorbs excess moisture and then changes its shape. After covering the layer with a polyethylene-based film, a rough screed is poured in a layer of about eight centimeters. Next, waterproofing is installed on it from two polyethylene layers laid overlapping. Please note that the polyethylene must be very tightly connected to each other to prevent moisture from entering the room.
- extruded polystyrene foam;
- mineral wool;
- foam glass;
- polystyrene foam, etc.
After this, a finishing screed is constructed, which is necessarily reinforced. To ensure the evenness of the screed, it is recommended to use beacons.
Concrete floor on the ground manufacturing technology
The construction of the floor should begin only after the walls and roof have already been erected. Manufacturing procedure concrete covering on the ground includes the following stages:
- carrying out work to determine the height of the floor and marking it;
- cleaning the top layer of soil and compacting the base;
- installation of gravel or crushed stone;
- hydro- and thermal insulation works;
- strengthening concrete screed;
- installation of formwork for pouring mortar;
- direct filling.
The ground floor is built so that it is flush with the doorway. Markings should be applied around the perimeter of the building. To do this, marks are placed on the walls at a distance of 100 cm from the bottom of the opening. When the marking is completed, you should lower it back one meter. This line will become a guide for pouring concrete. To make marking easier, you should install pegs in the corner parts of the room on which the ropes are tensioned.
The next stage of work involves clearing the base from the top layer of soil. First you need to get rid of any debris on the floor. Gradually remove all of the top soil. The concrete floor on the ground has the appearance of a structure, up to 35 cm thick. Therefore, the soil that is removed from the surface must be exactly this thickness.
Using special equipment, such as a vibrating plate, the surface is compacted. If it is not available, it is enough to use wooden log, with handles previously nailed to it. The resulting base should be even and dense. There should be no marks left on it while walking.
If the soil is located lower than the doorway, only the upper part is removed, the surface is compacted well, and then covered with sand.
Next, work is carried out on the installation of gravel and crushed stone. After compacting the base layer, gravel is backfilled; the thickness of this layer is about 10 cm. Tip: After filling, the surface is watered and compacted again. To simplify control over the evenness of the surface, it is necessary to drive pegs into the ground, set in relation to the level.
After the gravel layer, leveling is done with sand. The layer should have the same thickness, about 10 cm. In order to control the evenness of the surface, use the same pegs. To construct this layer, it is recommended to use ravine sand, which has various impurities.
Crushed stone is laid on the sand, with a fraction of 4x5 cm. Next, it is compacted, and the surface is sprinkled with sand, leveled and compacted. Lay the crushed stone in such a way as to avoid the appearance of protruding edges on the surface.
Please note that each of the layers laid on the floor must first be checked for horizontalness. Therefore, during the work, use a building level.
Thermal and waterproofing of concrete floors on the ground
To create a waterproofing layer, it is enough to apply polyethylene film or membranes. The waterproofing material should be rolled out along the entire perimeter of the floor; try to extend its outermost sections a few centimeters beyond the zero markings. The sheets are overlapped and fixed to the surface with tape.
In order to improve the thermal insulation of the floor and prevent the ground from freezing, it is recommended to treat the floor with mineral wool.
Features of reinforcing a concrete floor on the ground
In order for concrete to acquire the required strength, it must be reinforced. To perform this process, it is recommended to use a metal or plastic mesh, reinforcement bars or reinforcing wire.
To install the reinforcing frame, special stands should be equipped, the height of which is about 2.5 cm. Thus, they will be located directly on the concrete floor.
Please note that using a plastic mesh involves stretching it over previously hammered pegs. When using wire, the manufacture of a reinforcing frame will require welding and skill in working with it.
In order for the pouring procedure to go quickly and the result to be of high quality, the guides should be installed and the formwork mounted. Divide the room into several equal sections, the width of which is no more than 200 cm. Install guides in the form of wooden blocks, the height of which is equal to the distance from the floor to the zero mark.
To fix the guides, use thick cement, clay or sand mortar. Formwork is installed between the guides, which forms cards filled with concrete mortar. It is recommended to use moisture-resistant plywood or wooden boards as formwork.
Please note that the guides and formwork are brought to zero and aligned with the horizontal surface. In this way, it will be possible to obtain a base that is even. Before installing the guides and formwork, they should be treated with a special oil, which will facilitate the procedure of pulling them out of the concrete mixture.
Technology of pouring a concrete floor on the ground
Filling is carried out once or maximum twice. Thus, it will be possible to build a homogeneous and powerful structure. In order for the concrete floor on the ground to serve its owners with their own hands for a long time, it is best to order a special concrete solution from the factory. Its strength and quality are much higher than those prepared at home.
To make your own solution, you will need a concrete mixer, cement grade of at least 400, river sand and filler in the form of crushed stone.
In order to prepare a concrete solution, you should mix one part of cement, two parts of sand and four parts of filler, and, based on the total amount of ingredients, half of the part of water will be required.
All ingredients are mixed in a concrete mixer, make sure that all ingredients are mixed well together. Start pouring the floor from an area opposite to the entrance to the room. Fill three or four cards at once, and then use a shovel to level the composition over the entire surface.
To ensure good adhesion of concrete to the surface, it is recommended to use a hand-held concrete vibrator.
After most of the cards are filled, it is necessary to perform a rough leveling of the surface. For these purposes, you will need a rule two meters wide, which stretches smoothly across the floor. This rule will help get rid of excess concrete that ends up in empty cards. After leveling, remove the formwork and fill the remaining areas with mortar.
After leveling the entire floor area, cover the floor with polyethylene film and leave for a month. Please note that after several days, the surface is constantly moistened with water to avoid drying out of the concrete, the formation of cracks and looseness of the base.
The final stage involves treating the floor using mixtures on a self-leveling basis, which are used to equip the screed. It is the mixture that will help make the base perfectly smooth and eliminate minor surface irregularities.
Work also begins from the corner opposite the door; it is recommended to use a shovel to apply the solution, and a rule to level the base.
The floor is left to settle for 72 hours. Next, the floor is ready for laying finishing materials for flooring. It is this type of concrete floors on the ground in a private house that will provide a strong and durable foundation.
Concrete floors on the ground video:
Despite their high strength, concrete screeds may require additional reinforcement. This is relevant in conditions of high mechanical loads, when pouring unconnected structures, in case of shrinkage and deformation of concrete.
Work on reinforcing a concrete floor is not always carried out. But reinforced structures benefit in terms of operational and technical specifications. Steel protects the screed from cracking that occurs during the maturation of concrete due to natural shrinkage.
The construction of a reinforced concrete floor is reasonable in order to protect the structure from mechanical pressure and vibration loads. In general, we can talk about long-term operation.
When installing a reinforced concrete floor:
- if the project includes a floating screed. This issue is especially relevant in the presence of loose substrates, in the presence large quantity layers (steam, hydro, thermal insulation);
- if the floor is laid on the ground, which is due characteristic features soils (heaving, etc.), especially in the presence of expanded clay-based thermal insulation layers;
- current building codes and the rules dictate mandatory reinforcement in underfloor heating systems. Without reinforcement, such structures are more susceptible to deformation, which is due to constant temperature changes;
- concrete floors are always reinforced in industry, especially in areas with high traffic loads and under heavy equipment.
Reinforcement is a mandatory stage of work when the height of the concrete layer is over 50 mm
Materials used
When pouring concrete screeds, only those reinforcing materials are used that are permitted for use by current standards and regulations.
This group includes:
- steel mesh (reinforcing, wire);
- fiberglass – for volumetric reinforcement;
- fiberglass mesh;
- meshes based on modern polymer materials.
Certainly the most durable structures are created based on metal fittings. They are successfully used in industrial premises, garages, warehouses, and open street areas. The solution is suitable for installing screeds on the ground.
Fiberglass and polymers optimally meet the requirements of screeds for heated floors. They are not suitable for building structures on the ground. Such materials are lightweight, do not put additional load on the floor, but do not have good tensile strength. You could say that this is perfect solution for places with light loads.
Volumetric strengthening with fiber fiber provides protection against shrinkage deformations and blocks the formation of microcracks. The material is introduced into the concrete formulation, but is not suitable for working on soils (or is used in combination with traditional reinforcement).
In addition, fibrous varieties do not provide protection against bending and tensile stresses.
Nuances of reinforcement of concrete floors
For concrete floor structures that will bear high and ultra-high loads, it is better to choose metal reinforcement. The diameter of the rod is determined depending on operating conditions and loads. In practice this is 6-12 mm. The most common cell size is 10*10, 20*20 mm.
The reinforcing mesh can be connected into a single system using knitting wire or by welding. Both options work successfully in ground screeds. Current standards allow the installation of mesh in two layers. The cost of reinforcement depends on the mesh size, material consumption, and rod diameter.
Ready-made wire mesh is available in sheets and rolls. The base is wire of class VR-1 and d 2-6 mm. The material is suitable for constructing rough screeds under moderate load conditions. Cell sizes can vary between 50*50 – 200*200 mm.
Principles of working with metal reinforcing mesh:
- Regardless of the technology used, the mesh must be placed in the thickness of the concrete. This will protect the steel from corrosion;
- the base is cleaned of peeling, dirt, dust;
- discovered cracks must be expanded, dust-free, treated with primer and sealed with repair mortar;
- the base is primed in 2-3 working approaches;
- hydro- and soundproofing flooring is carried out with gluing of overlaps and going onto the walls;
- markings are made using a level;
- the reinforcing mesh is laid on supports so that the material is in the body of the concrete, observing an overlap of one cell;
- the joints are tied with knitting wire;
- Beacons are mounted on top of the reinforcement layer using metal U-shaped profiles;
- a solution is laid out between the beacons, and alignment is carried out using the rule;
- When the concrete has set, the guides are dismantled and the resulting voids are filled with mortar.
The screed is protected by a covering material and is protected for 5-7 days
Features of reinforcement with plastic mesh
If the concrete structure is installed on floor slabs and too high loads are not expected, it makes sense to turn to plastic reinforcing mesh. This is the optimal solution for strengthening screeds up to 80 mm thick, including when implementing self-leveling systems and heated floors.
The advantages of such materials are much lower weight compared to steel and high elasticity. Plastic is capable of stretching, which helps maintain the integrity of the structure during shrinkage processes.
The material is sold in rolls at an affordable price (from 120 rubles/sq.m.). You can count on convenient transportation, installation, cutting. Plastic is not subject to corrosion and is resistant to aggressive environments. The reinforcement technology is identical to the previous one.
Features of the use of fiberglass materials
Only fiberglass that has been treated with a special impregnation works with concrete. This prevents the destruction of the material in an alkaline environment, which is typical for cement mortars. The most common reinforcing meshes are woven on the basis of aluminoborsilicate glass.
If we talk about the advantages, they are identical to their polypropylene counterparts. The scope of application is the same as that of plastic mesh. Fiberglass is an easy to transport, lightweight, elastic material, but it does not withstand high temperatures (maximum 200 degrees) and is unsuitable for areas with an increased risk of fire.
Features of volumetric reinforcement
The basis of such amplification is a mixture fibrous materials. It can be polypropylene, metal, basalt, fiberglass. The material is introduced into the concrete formulation during the preparation of the solution. After the screed gains strength, a monolithic coating is formed that is minimally susceptible to cracking.
The choice of material type is based on the purpose of the screed. Thus, lightweight structures require polypropylene and fiberglass. For higher loads, it makes sense to pay attention to metal varieties. If the structure will be used in difficult conditions or on outdoors, basalt fiber is used.
When mixing the solution, the fiber is poured at the stage of mixing the dry components, after which mixing with water is carried out. The composition is laid out on the base and aligned along the guides. Volumetric reinforcement is easily combined with traditional reinforcement.
Concrete floor installation work
The construction of a concrete floor is realized using the following technological operations:
- pouring a reinforced concrete slab of appropriate thickness, or compacting the soil, installing a sand-crushed stone cushion;
- reinforcement in one layer;
- pouring concrete along guides, class not lower than B22.5. The guides are arranged using an optical level. Leveling is carried out using an aluminum rule (5-7 m). Without guides they work on liquid beacons using a vibrating screed. The screed is compacted using deep vibrators;
- Grouting is carried out using concrete troweling machines when the base gains strength and can withstand the weight of a person and equipment. During the operation, the film formed as a result of hardening of the solution is removed. Work is carried out 3-6 hours after laying the solution at a temperature not lower than +20 degrees;
- second grouting and smoothing with the blades of a trowel to a mirror shine;
- distribution of care products using rollers;
- filling the seams with sealing profile materials.
It is necessary to cut expansion and temperature-shrinkage seams with a cutter to a depth of 1/3 of the thickness of the structure
Detailed list of works
Sand is poured over the compacted soil base. The average layer thickness is 200 mm. Layer-by-layer compaction is carried out using vibrating plates. The sand must be compacted in accordance with the design marks, which is controlled by a level. Another technology involves the installation of reinforced concrete slabs.
Installation of formwork, guides
The concrete floor is laid separate sections- cards. These are rectangular zones of the required size. Actual fill map parameters depend on total area surfaces and the possibility of laying mortar in one shift.
Formwork is installed along the perimeter of the cards below the finished floor mark. Material – wooden board 50*100 mm. Holes for reinforcement pins should be pre-drilled in the boards in increments of 50 cm. The formwork lines should overlap the pattern of expansion joints.
If the installation will be carried out along guides, they are arranged on the basis metal profiles, either a steel angle 50*50*3 mm, or a profile pipe 40*20*2 mm.
The guides are welded to reinforcement posts with a diameter of 12 mm. Evenness is controlled by an optical level. All places where the surface adjoins load-bearing structures are covered with damper tape based on foamed polyethylene, for example, Izolon 4 mm thick.
Before filling, the profiles should be treated with engine oil. The rough base is moistened with water.
Reinforcement
IN concrete floors reinforcement is carried out in accordance with the design, based on the expected loads. You can use welded road mesh with a diameter of 4 mm and a cell size of 20*20 cm. The material is laid in one layer, overlapping is provided. Reinforcement clamps - chairs - are installed to ensure protective layer at 20 mm.
All overlaps are fixed with tying wire with a diameter of 1.2 mm. Overlaps and protective layers are monitored. Before laying the reinforcing mesh frame on the base, it is recommended to place a polyethylene film. This will reduce moisture loss from the concrete mixture and provide waterproofing.
If the project requires laying reinforcing mesh in two layers, you can use a road mesh with a diameter of 5 mm and a cell size of 15 * 15 cm. The bottom layer is mounted on plastic clamps (support 35-50), which will give a protective layer of 35 mm.
The upper one is mounted on special strip clamps, taking into account gaps in the areas of shrinkage and technological seams. For work, use strip clamps FP 60-4.0. They are connected to the mesh with a knitting wire and provide a protective layer of 25 mm.
Concrete laying
When laying concrete according to maps there should be no long technological breaks, that is, more than 60 minutes
After installing the reinforcement and formwork, it is time to pour the concrete mixture. The choice of material is based on the type of structure, method of installation and transportation. When working on floors, a class of at least B22.5 is used.
If the area and working conditions do not allow the mixer to approach the object closely, concrete pumps are used. For small jobs, concrete mixers are used. Filling must be continuous, otherwise there is a high risk of cracking.
To increase the plasticity and workability of the solution, it is permissible to introduce C-3 plasticizers into the formulation (in the factory).
Leveling and compaction
The solution is compacted using deep vibrators. To level along the guides, use a rule. Work with the surface is carried out in 3 technological approaches. If the concrete shrinks, the solution is added with a shovel in the required quantities.
Control over the correctness of installation is carried out using a level, which complies with SNiP 3.04.01-87.
If the guides were mounted on liquid beacons, they operate with deep vibrators and vibrating laths. The work is carried out in 2 working approaches. This technology requires plasticity and workability of the solution, for which it is recommended to introduce plasticizing additives C-3. The concrete is laid and leveled so that the top is slightly higher than the level of the vibrating screed. Next, the tool is pulled along the liquid beacons.
Under the influence of vibration, the solution settles to the required level and is leveled. But, you need to make sure that the tool constantly slides over the surface. If material settles below the level, it is added with a shovel.
Grout
Before grouting, a technological break is arranged. The structure must gain the required plastic strength. Final time depends on humidity and temperature environment. As a rule, 2-7 hours are enough.
During this time, the material will gain strength so that you can safely step on its surface without leaving marks deeper than 3 mm. They begin processing with a trowel with discs using several technological approaches. Where concrete is adjacent to enclosing structures, walls, doorways, columns, grouting is carried out first. This is due to the fact that in these areas the solution gains strength faster than in the main area.
Primary application of dry hardeners
After grouting, take the dosing cart and add dry topping. Quantity – 50-60% of total consumption. On average, this is 1-1.5 kg/sq.m. The total consumption is within 2.5 kg/sq.m., but can increase equivalent to an increase in floor loads.
When the composition absorbs moisture from concrete slab, which can be seen by darkening, the first grouting is carried out using concrete finishing machines with a disc. Work begins near walls, columns, doorways . Work continues until a uniformly mixed mixture is formed on the surface.
The topping must be completely saturated with cement laitance and bond to the surface.
Second application of hardener
When the first grout is completed, the remainder of the mixture is immediately spread. This way the topping will have time to become saturated with moisture from the cement milk before the water evaporates. Application is carried out in such a way as to compensate for possible uneven application of the first layer.
When impregnation with moisture has occurred, which is traditionally indicated by darkening, the second grouting begins. Continue until the topping is completely saturated. If additional compaction is required, processing can be duplicated.
Smoothing
The final grouting is carried out using blades. Based on the condition of the surface, the interval between approaches is determined. The concrete should become matte without staining your hands when touched. The work is completed when a smooth, even surface is formed.
Now you can coat the concrete with polymer compounds. The material is applied with rollers. This will prevent too rapid loss of water.
Cutting temperature-shrinkable seams
2-3 days after completion of work, cutting of shrinkage and technological seams should be carried out. To determine the readiness of concrete for work, a test cutting is required. The edges of the seam should not crumble or become painted.
Seams are required to compensate for shrinkage and temperature processes occurring in the structure during concrete hardening. Plus, they prevent linear temperature deformation that occurs during operation.
Map for cutting seams: from 2.5*2.5 m to 3*3 m. The pattern must coincide with the axes of the columns. In the area of the columns, cutting is done in the shape of a diamond. They act in such a way that the glass of the column is placed inside the rhombus. The cutting depth is 1/3 of the thickness of the screed. Width – no more than 3-5 mm. Next, the recesses are filled with sealing cords. It is better to use a special profile seal.
What determines the price of a reinforced concrete floor?
The overall level of costs is based on a number of factors, the main of which are the presence of upper protective layers, area, number of layers, type of reinforcement, and quality of concrete.
Area is practically the only factor that cannot be influenced in any way. The larger the room, the more expensive the work will cost. However, large companies offer discounts for large volumes of work.
The quality of the mortar, the presence and type of reinforcement affect not only costs, but also the overall characteristics of the finished structure. Trying to save on price will result in the floor having to be repaired or replaced. Conversely, an excessive number of layers and unreasonably reinforced reinforcement will increase the load, and with the slightest mistakes this will lead to loss of durability of the coating.
The presence of upper reinforcing layers has a very significant effect on the cost of the floor.. But against the backdrop of such costs, the durability of the system increases.
The layers provide protection to the floor from excess humidity, mechanical damage
conclusions
The quality of a concrete floor is directly dependent on the quality of the concrete. When choosing the optimal solution, they focus on the strength, durability, and moisture resistance of the material, therefore work on the construction of the structure begins with the selection of the class of concrete, as applied to each specific object. It's important to organize proper preparation, backfilling and compaction of the lower layers of the structure.
If we talk about reinforcement, the rule here is that too much does not mean good. The reinforcement system must be designed taking into account operational loads and operating conditions. Otherwise, you can expect excessively high costs and excessive loads on the foundation.
Otherwise, the production of concrete floors requires the participation of conventional building materials and equipment: concrete mixers (unless ordered ready material), brushes, rollers, shovels, polyethylene films, reinforcing additives, etc.
The process of reinforcing a floor under a concrete screed is shown in the video:
In this article we will analyze in detail the design and construction of a monolithic concrete floor on the ground. By “floor on the ground”, further in the article, we will mean a concrete floor made inside the contour of the foundation, directly on the ground. Let's consider FAQ associated with this floor, and the structure itself from the ground to the finishing surface.
For what types of foundations can a floor be made on the ground?
A concrete floor along the edge can be used with a strip foundation, and with a columnar foundation (or a foundation using TISE technology). The slab foundation itself (by its design) is also a floor on the ground. With a strip foundation, the floor structure is usually adjacent to the foundation wall.
Rice. 1. Connection of the floor along the ground to the strip foundation
Rice. 2. Connection of the floor along the ground to columnar foundation with a low grillage
With a columnar foundation or a foundation using TISE technology, the floor structure along the ground can be adjacent to the grillage (if the grillage is low), or located below the grillage (if the grillage is high).
In the case of a high grillage, the gap between the floor structure and the grillage is closed when the floor is filled, for example, with boards (can be unedged). These boards remain in the structure and are not removed, Figure 3.
Rice. 3. Connection of the floor along the ground to the columnar foundation in the case of a high grillage
The height of the floor on the ground relative to the strip foundation
Rice. 4. Floor on the ground on the expansion of the belt
Rice. 5. The ground floor is adjacent to the wall of the strip foundation
Rice. 6. The ground floor is located above the foundation strip
Rice. 7. The ground floor is adjacent to the top of the tape
There are no constructive mandatory recommendations regarding the mark (height) of the floor installation on the ground. It can be installed at any height shown in Figures 4-7 above. The only thing you need to pay attention to when choosing this option is where the height of the front door will be. It is advisable to attach to the mark of the bottom of the door so that there is no difference between the bottom of the door and the floor, as in Figure 8, or so that you do not then need to cut an opening in the tape for the door.
Rice. 8. Height difference between the ground floor and the doorway
Rice. 9. The floor is level with the doorway
Note: Opening under front door it is better (more correct) to provide for it at the stage of filling the tape. Just do not fill this place, insert boards or foam plastic there, so that there is an opening in the tape. If you forgot to leave the opening, then you will have to either make the entire floor higher (and this will increase the cost of bedding), or cut an opening in the finished strip, cut the reinforcement in it, weaken it, etc.
Thus, if the opening under the front door is made correctly (at the stage of filling the tape), then we arrange the floor on the ground so that the top of the floor is level with the opening under the door (taking into account the finishing coating). In order to correctly calculate the thickness of the floor structure, and determine at what point you need to start its construction, you need to understand what the thickness of all its layers will be, what this depends on. More on this later.
There are no such cases. Even when the groundwater level is high, it is more correct to install a monolithic floor on the ground than a floor on joists, for example. The type of soil, seismicity, level of freezing - all this also does not affect the possibility of installing such a floor.
Note: We do not consider situations where the house is raised above the ground on stilts; it is clear that then such a floor is not suitable.
Options for floor construction on the ground
Rice. 10. Floor construction on the ground with a ground water level higher than 2 m (with waterproofing)
Rice. 11. Floor construction on the ground at low ground water level, below 2 m, with bedding
Rice. 12. Floor construction on the ground at low ground level, below 2 m, without bedding, with pouring instead of rough screed
Rice. 13. Floor construction on the ground at low ground level, below 2 m, without bedding, with a rough screed
Rice. 14. Construction of the floor on the ground in combination with a warm floor
Note: Figure 14 shows the underfloor heating pipes and the reinforcing mesh above them. Between the floor pipes and the reinforcing mesh, - no gap, just drawn for clarity.
Description of the main floor layers based on the ground
Let's analyze the main layers (pie) of the floor according to the ground. Let's look at the structure from the bottom up. We will describe all the layers that may exist, without reference to a specific drawing.
- Compacted soil- the base for the floor must be well compacted;
- Bedding layers(sand 7-10 cm and crushed stone 7-10 cm). Bedding layers can be used to protect against capillary rise of water and can be used as a leveling layer. The crushed stone in the bedding layer should be of a fraction of 30-50 mm (large). The sand in the bedding layer can be of any kind, both river and quarry (gully). Whether the crushed stone can be replaced with expanded clay depends on the purpose for which the bedding is made; you can read about this in the paragraph Is it possible to replace crushed stone with expanded clay, in the same article, below. It is important that the bedding layers are well compacted. There are conditions when a bedding device is necessary and when it is not. You can read about this in the paragraph What determines the design of a floor on the ground, in the same article, below;
- Rough floor screed on the ground. This is a layer on top of bedding or compacted soil. Performed by plastic film(it spreads on the ground or bedding), the thickness of the rough screed is 5-7 cm. It does not need to be reinforced. Sometimes rough screed replaced by pouring. About pouring - in the next paragraph, about when you can replace the rough screed with pouring - in the paragraph Is it possible to replace the rough screed with pouring, in the same article, below. The crushed stone in the construction of the rough screed should be of a fraction of 5-10 mm (fine). The sand in the construction of the rough screed must be river sand, not quarry (gully);
- Pouring (pouring) the floor over the ground. It is arranged by pouring a solution onto the bedding layer. The thickness of the pouring is equal to the thickness of the bedding layer. It fits without plastic film;
- Waterproofing. Constructed from roofing felt, 1-2 layers. You can take the most ordinary roofing material, without sprinkling. There are conditions when waterproofing is mandatory. You can read about this in the paragraph What determines the design of the floor on the ground below;
- . As insulation for floors on the ground, we recommend using EPS with a density of 28-35 kg/m 3, or polystyrene foam with a density of 30 kg/m 3 and higher. The thickness of the insulation is determined by calculation (depending on the climate zone);
- Finishing screed. The thickness of the finishing screed is 7-10 cm. The crushed stone in the construction of the finishing screed should be of a fraction of 5-10 mm (fine). The sand in the construction of the finishing screed must be river sand, not quarry (gully). The finishing screed (as opposed to the rough screed) must be reinforced. Reinforcement is performed with a mesh with a wire diameter of 3-4 mm. How to choose, 3 mm or 4 mm, is written in the paragraph What determines the design of the floor on the ground below;
- Finish coating . The final finish of the floor on the ground can be anything. Accordingly, the details of the device are different for each type of coating.
Presence and sequence of floor layers on the ground
What determines the design of the floor on the ground:
- From the groundwater level;
- It depends on whether these floors will be with heat transfer fluids (warm) or not;
- From operational loads on floors.
How exactly the construction of a floor on the ground depends on these factors will be discussed below.
1. By the presence of waterproofing. Our recommendations: install waterproofing from roofing felt (1-2 layers) if the groundwater level lies closer than 2 m from the bottom of the floor along the ground. In addition, if the groundwater is located closer than 2 m, we recommend making a backfill of sand and crushed stone, Figure 10. If the level is lower than 2 m, then the floor can be made without waterproofing. At a level lower than 2 m, backfilling with sand and crushed stone is not necessary, Figure 11, 12, 13.
Note: You need to focus on the highest groundwater level that may be at a particular construction site. That is, look at how high the water rises in the spring, during a flood, etc., and take this level into account.
2. If there are coolants in the floor structure on the ground, you need to make a gap between the walls and the floor, 2 cm. This requirement is the same for both water and electric heated floors. The gap is made at the level of the finishing screed (with coolant). All layers below the finishing screed are placed against the walls without a gap, Figure 14. You can read more about the installation of a water-heated floor in the article.
3. If it is planned that something heavy will be placed on the floor on the ground (heavier than 200 kg/m2), then we reinforce the finishing screed with a mesh with a wire diameter of 4 mm. If the load is up to 200 kg/m2, then it can be reinforced with a wire mesh with a diameter of 3 mm.
Important points when installing a floor on the ground
I would like to analyze these important points based on the questions that, as a rule, arise among readers of our portal when installing a floor on the ground.
Can interior walls be placed on this floor?
Yes, you can install a screed reinforced with 4 mm wire interior walls made of brick (in brick), from a partition block (100 mm), and a wall half a block thick. By “block” we mean any block (expanded clay concrete, shell rock, aerated concrete, foam concrete, etc.)
Is it possible to replace crushed stone in the bedding layer with expanded clay?
Backfilling is usually done in order to interrupt the capillary rise of water. Expanded clay swells with water and is not suitable as a bedding material. That is, if the bedding was planned as additional protection from water - such a replacement cannot be made. If the backfill was not planned as protection, but simply as a leveling layer, and the water is far away (deeper than 2 m from the base), and the soil is constantly dry, then you can replace crushed stone with expanded clay to install a floor on the ground.
Is it possible to replace the crushed stone in the bedding layer with broken bricks and waste construction materials?
It is forbidden. If the bedding was planned as additional protection from water, then broken brick and other waste will not fulfill its purpose in the bedding. If the bedding was not planned as protection, but simply as a leveling layer, then we also do not recommend such a replacement, since these materials have different fractions and will be difficult to compact well, and this is important for normal operation floor designs.
Is it possible to replace the crushed stone in the bedding layer with expanded clay, pour more of it, and then not put insulation?
To replace 50-100 mm of EPS (this is the average amount needed to insulate a floor on the ground), you will need 700-1000 mm of expanded clay. It is impossible to properly compact such a layer, so we do not recommend doing this.
Is it possible not to reinforce the screed?
You don't have to reinforce the rough screed. The finishing screed must be reinforced.
Is it possible to reinforce the screed with something other than mesh? Instead of reinforcing mesh, is it possible to simply put metal rods in the screed without tying them together, or other metal parts?
No, for reinforcement to work, it must be done with a mesh.
Is it possible to lay waterproofing directly on bedding layers?
No, waterproofing must be laid on a flat and solid base (in our case it is a rough screed), otherwise it will quickly become unusable due to uneven loads.
Is it possible not to make a rough screed and put waterproofing or insulation (if there is no waterproofing) directly on the bedding layers?
We discussed waterproofing in the paragraph above. The insulation also needs to be laid on a flat and solid base. This base is the rough screed. Otherwise, the insulation may move, and subsequent layers too, and this may lead to cracks in the floor.
Is it possible to do a wash instead of a rough screed?
Let's look at what we mean by “rough screed” and “shedding”. A rough screed is a layer on top of bedding or compacted soil. It is carried out over a polyethylene film (it is spread on the ground or bedding), the thickness of the rough screed is 5-7 cm. The pouring is done by pouring the solution onto the bedding layer. The thickness of the pouring is equal to the thickness of the bedding layer. It fits without plastic film. Now let’s talk about whether the rough screed can be replaced by pouring. If the water is closer than 2 m, and the backfill (sand and crushed stone) was used as a layer that prevents capillary rise, then watering cannot be done. Because spilled crushed stone will not interrupt the capillary rise of water. If the backfill was carried out for leveling purposes, and the water is deeper than 2 m, then you can use a backfill instead of a rough screed. If there is no bedding at all, and the screed is done directly on the compacted soil, then you can do both a rough screed and a pour. It just turns out that there is no point in doing the pouring, since for it you will still have to pour about 3 cm of sand and about 10 cm of crushed stone, and in this case the sand is river sand, and the crushed stone fraction is about 10 mm. In general, it is easier to do a regular rough screed.
Does polyethylene under the rough screed replace waterproofing?
The function of this layer is to prevent concrete milk from going into the bedding layers or into the ground. This layer is purely technological; it does NOT replace the main waterproofing (roofing felt on top of the rough screed). If the water is deeper than 2 m, then waterproofing (roofing felt) is not needed, but this does not mean that we “replaced” it with polyethylene. It’s just that these layers have different functions and do not replace one another. When installing a rough screed and water deeper than 2 m, a layer of polyethylene is still needed.
Where is the correct place to place the reinforcing mesh in the finishing screed?
Does it matter where exactly the reinforcing mesh is located in the finishing screed layer (at the bottom, at the top or in the center)? If the screed is without coolants, then the mesh should be located 3 cm from the top of the screed (that is, approximately in the middle). If the screed contains coolants, then the mesh must be on top of the pipes, plus 2-3 cm of a protective layer.
Rice. 15. Finish screed without coolants, reinforcement
Rice. 16. Reinforcement of finishing screed with coolants
Some may say that concrete screed is not particularly reliable and always remains cold. And its advantages include, perhaps, cost-effectiveness, environmental friendliness and fire resistance. This was the case before, but the application modern materials and advanced technologies makes the service life and reliability of the screed significantly higher, and heat insulators provide a comfortable surface temperature.
The construction of a concrete screed on the ground is not always rational decision. There are certain restrictions that must be taken into account:
- lack of a basement or ground floor;
- the occurrence of groundwater at a depth of at least 4-5 meters;
- the presence of heating in the house, since freezing of the soil can lead to deformation of the screed due to the higher load on the foundation.
Having decided to create a concrete floor on a soil foundation, you need to make sure that the house is not in danger of flooding. You can start arranging the screed only after the walls and roof of the structure have been erected.
Concrete pavement on an earthen base consists of several layers, each of which performs an important function. Layers are created from various materials; as a rule, the “pie” includes the following components:
- sand layer;
- crushed stone or gravel layer;
- waterproofing material;
- rough concrete floor;
- steam and heat insulation layer;
- clean concrete floor.
As a finisher flooring can be any commercially available material that matches stylistic direction interior and most harmoniously fits into the design of the home.
Under no circumstances should you start pouring concrete directly onto the ground, because the first two layers of the “pie” prevent the penetration of moisture from the soil into the floor covering, which can occur by capillary action. Creating a concrete screed is not the easiest or fastest process. The main difficulty is that the work takes place in several stages. There is no need to cut corners, because the end result should be a high-quality coating that is not prone to dust formation, is sealed and can withstand loads.
The layered structure is the key to a long service life of the screed and its wear resistance. Modern technology for creating concrete screeds can be divided into two big stage: preparatory work and direct arrangement of the concrete surface. Each of these stages consists of several parts.
Video - Floor screed on the ground
Preparation for laying a concrete screed on the ground
Preparatory work is a mandatory stage in creating a concrete floor; it is they that take up the lion's share of time in the process of arranging the screed. But it’s impossible to do without them, unless, of course, you want to get a low-quality result.
Filter layer
First of all, it is necessary to deal with the compaction of the earth in the base, which will help prevent its subsidence and, accordingly, possible cracking of the screed. Concrete floors on the ground are often installed in combination with strip foundation at least 1-1.5 meters deep, filled with sand inside.
But this approach is not acceptable if the house is located on a clay plot. After all, clay retains moisture, therefore, if there is sand inside the foundation, stagnation of water will form and a real “pond” will appear under the building. That is why drainage is required in clayey areas.
The most optimal procedure in this case is the following:
- The clay extracted during the creation of the pit is filled with its lower part;
- performed internal thermal insulation home and external insulation foundation. These actions are aimed at leveling soil heaving even in the absence of heating in the building;
- gravel is poured onto the prepared soil and then thoroughly compacted. The quality of tamping in this case is very great importance, since we are talking about preventing the formation of voids. It is carried out using special tamping mechanisms;
- sand is poured onto the gravel, which is also carefully compacted and smoothed.
The thickness of the filter layer depends on the characteristics of the soil; as a rule, sand and gravel beds are no thicker than 15-20 cm each.
Waterproofing layer and rough screed
After filling the foundation, you can begin arranging the waterproofing of the future screed. The most popular materials for this purpose are polyvinyl chloride and bitumen-polymer membranes. If the moisture level for the house is within normal limits, then you can get by with a regular polyethylene film 250 microns thick, which is laid in two layers.
The edges waterproofing material should be slightly higher than the expected level of the finished concrete screed. Special attention It is worth paying attention to laying waterproofing in the corners, since it is through them that moisture most often penetrates. If the material does not completely cover the perimeter of the room, then its elements are overlapped and fixed with tape.
The optimal material for rough screed is “lean” concrete, to which crushed stone has been added. The resulting surface does not have to be perfectly flat, and high requirements are not applied to her. It is quite enough if it does not have differences in height of more than 4 mm. In this case, its thickness should be about 4 cm.
Thermal insulation layer
Insulation of concrete screed - important stage Therefore, a lot of attention is paid to the choice of thermal insulation material. He must have the following qualities:
- high strength;
- low thermal conductivity;
- fire resistance;
- ease of use.
Most often, preference is given to foam, polystyrene foam or a layer of mineral wool. Required thickness The material is determined by the location of the house. For example, in central Russia, slabs 10 cm thick can be used for insulation, in less warm regions - up to 20 cm.
The laid thermal insulation material must be covered with a polyethylene film on top, which serves two purposes at once: it prevents penetration concrete mortar into the space between the insulation elements and provides a vapor barrier.
Stages of arranging a concrete screed on the ground
Preparatory work ends after the creation of the thermal insulation layer. However, you cannot immediately proceed to pouring concrete - you need to take care of the strength and reliability of the future structure.
Screed reinforcement
The next step is laying reinforcement, which will give the concrete coating additional strength and durability. Traditionally, road mesh is used for this purpose; the diameter of the bark rods varies between 5-6 mm. The dimensions of the cells are 100*100 mm or 150*150 mm. Such reinforcement will prevent the appearance of cracks in the screed during shrinkage.
It is best to place the reinforcing layer a few centimeters above thermal insulation material, since this way it will end up inside the concrete covering. If the operational load of the floors is very high, then a reinforcement cage is used to strengthen them.
The photo clearly shows the mesh laid on the waterproofing
Creating formwork
Before the construction of the final concrete screed begins, guides and formwork are installed. This technology allows you to more accurately maintain a given level. The available area is divided into equal sections, the width of which does not exceed 2 m. After this, guides are installed, their height must correspond to the desired level of the screed. The guides are attached using a cement solution into which clay and sand are added.
Then formwork is laid in the space between the guides, thereby dividing the base into rectangular parts, which are then filled with cement mortar. The guides and formwork are brought to the desired level and leveled horizontally, serving as a guarantee of the evenness of the future coating. After pouring, they will be removed from the concrete, which is quite difficult to do, so to simplify this process they are coated with a special oil.
In order to obtain a monolithic surface, the screed is poured in several passes:
- work begins from the corner located on the opposite side of the door. After filling several rectangles, the solution is distributed over the entire area using a spatula;
- then the time comes rough alignment, which is carried out by movements towards you, while excess concrete is removed;
- in the treated areas, the formwork and guides are removed, and the resulting voids are filled with a cement mixture.
This procedure is maintained until the entire floor area is filled. For sealing concrete surface You can use a special vibrator, which will speed up the process and remove all voids. When the screed is completely ready and leveled, it is kept under film for 3-4 weeks and periodically moistened. A leveling screed made of concrete M-100 and higher can be poured over the finished monolithic surface.
Creating a floor screed on the ground is a task that even home craftsmen can do. Modern technology The process is simplified as much as possible, the main thing is to follow the stages of work, do everything efficiently and listen to the advice of specialists:
- The screed level is set taking into account existing or planned doorways. Level markings must be carried out along the entire perimeter of the base. Stretched cords will help make orientation easier;
- if in preparatory work If a clay layer is involved, then it should be moistened and then compacted - such an obstacle will become almost insurmountable for groundwater;
- concrete screed on an earthen base - a multi-layer “pie”, each of the layers in which must be carefully aligned horizontally;
- the thermal insulation characteristics of a concrete floor can be improved using an expanded clay, cork or plywood layer;
- the thickness of the rough screed should be about 8 cm, and the thermal insulation layer should be at least 10 cm;
- while creating reinforcement cage for a concrete floor that will have to withstand severe operating loads, it is best to use rods with a diameter of 8 mm;
- The concrete surface is prone to cracks; to avoid this problem, expansion joints. After cutting, they must be sealed;
- To prevent the appearance of dust on the screed, special impregnations are used, which are applied no later than 7 hours after compaction of the concrete layer.
It is very important to use high-quality materials when arranging a concrete screed, especially for the “filling”, that is, insulation and waterproofing. If they fail, the entire structure will lose its strength and will not last long. You should not save on screed materials, otherwise you will subsequently have to spend significantly more money on repairs.
The result of carrying out competent work with quality materials will be the appearance of a reliable and durable concrete floor. It will not only withstand high operating loads, but will also serve as an ideal base for applying any of the topcoats on the market today.
Floors with a properly installed concrete screed will last for many years, or even decades. Observing technological sequence and paying due attention to all its stages, even an amateur who has very modest knowledge about the repair process and has minimal skills can cope with the creation of the screed.
Tables
| Concrete grade | Mass composition, C:P:SH, kg | Volumetric composition per 10 liters of cement P/Shch, l | |
|---|---|---|---|
| 100 | 1: 4,6: 7,0 | 41/61 | 78 |
| 150 | 1: 3,5: 5,7 | 32/50 | 64 |
| 200 | 1: 2,8: 4,8 | 25/42 | 54 |
| 250 | 1: 2,1: 3,9 | 19/34 | 43 |
| 300 | 1: 1,9: 3,7 | 17/32 | 41 |
| 400 | 1: 1,2: 2,7 | 11/24 | 31 |
| 450 | 1: 1,1: 2,5 | 10/22 | 29 |
| Concrete grade | Mass composition C:P:SH, kg | Volumetric composition per 10 liters of cement P/Shch, l | Amount of concrete from 10 liters of cement, l |
|---|---|---|---|
| 100 | 1: 5,8: 8,1 | 53/71 | 90 |
| 150 | 1: 4,5: 6,6 | 40/58 | 73 |
| 200 | 1: 3,5: 5,6 | 32/49 | 62 |
| 250 | 1: 2,6: 4,5 | 24/39 | 50 |
| 300 | 1: 2,4: 4,3 | 22/37 | 47 |
| 400 | 1: 1,6: 3,2 | 14/28 | 36 |
| 450 | 1: 1,4: 2,9 | 12/25 | 32 |
| Styrofoam | Polyurethane foam | Min. plate |
|---|---|---|
| Open cell structure | There is both open and closed cell structure | Fibers randomly located in vertical and horizontal directions |
| Poor moisture permeability | Almost impermeable to moisture | Almost does not absorb moisture |
| Lightweight material | Lightweight material | Medium-light material |
| Average strength | Low strength | Low/medium strength |
| Average compressive strength | Low compressive strength | Low to medium compressive strength |
| Non-toxic | Non-toxic, emits carbon monoxide and carbon dioxide at a temperature of 500 degrees | Non-toxic |
| Not suitable for use under high load | Not all slabs are suitable for use under high loads |
Concreting carried out with high speed over large areas, is the most economical way to level the old and install a new floor. After hardening smooth surface becomes the ideal basis for any finishing coating. To increase the service life of the screed, reinforcement of the concrete floor is used. This process is carried out using various materials and designs made from them.
According to the functions performed and location, the screed is divided into the following types:
- rough - rests on the ground;
- multilayer - includes heat and sound insulating gaskets;
- leveling - laid on a rough layer, serves as the basis for a floor covering or tubular insulation;
- construction - lies on the floor slab.
It is advisable to reinforce a self-leveling concrete floor when constructing rough and multi-layer screeds (in the absence of a monolithic support, the effect of tensile and bending loads is enhanced), as well as to reduce the design layer of concrete.
Types of reinforcing structures and materials
1. Frame made of rods. Most often it is laid in two layers, made from rods with a diameter of 6 to 40 mm. Used when coating thickness is more than 8 cm.
2. Steel wire mesh. Used for multi-layer screed on the ground or to strengthen the coating in the garage, hallway, kitchen.
3. Polymer mesh. It does not strengthen the screed, but only prevents cracking during the concrete hardening process. Used for self-leveling floors, reducing cement consumption. The mesh is installed directly on the base or on the heat-insulating layer.
4. Reinforcing fiber for concrete. There are two types: metal and polypropylene. Polymer fiber gives concrete resistance to cracking during shrinkage, temperature fluctuations, and enhances water-repellent properties.
Metal fiber increases the resistance of concrete to vibrations. Replacing reinforcing mesh steel fiber, save time (elements are introduced directly into the mixer), reduce the thickness of the screed. In this case, microcracks lose their ability to expand.
5. Combined reinforcement. In addition to the frame mounted in the lower section of the covering, it upper layer filled with fiber - this is how the concrete floor screed is protected from cracks. The method is applied to the entire surface or in areas of increased loads (where the floor is adjacent to walls or columns). Fiber should be dosed according to the instructions.
The main stages of concrete pavement reinforcement
The most labor-intensive is the construction of a concrete floor with a soil base. First, according to technology, a gravel-sand mixture is laid, then a foundation slab, parabarrier film, thermal and waterproofing. Next, a reinforced layer of concrete is installed.
1. Depending on the thickness of the screed, in private construction it is reinforced with a frame made of rods or wire mesh. The diameter of the reinforcement for reinforcement is taken from the range from 8 to 20, and the wire - from 4 to 6 mm. The cell size ranges from 10 to 20 cm.
2. A frame made of solid rods is knitted using wire with a diameter of 2 - 3 mm, the layers of the frame are attached to the ribs. If scraps of material are used, they are overlapped with an overlap of half a meter.
Wire mesh is purchased ready-made (cells 5 - 20 cm) or knitted by hand. Purchased products are connected with wire with an overlap of 1 - 2 cells.
3. Finished design placed on clamps (“chairs”) at a level of about 3.5 cm from the base. When pouring, the steel elements must be in the middle of the concrete layer - in this case, the loads are evenly distributed over the surface of the coating, its mechanical resistance is ensured, and there is no metal corrosion.
Reinforcement consumption for floor reinforcement
Table 1 shows data for the mesh version of the reinforcement, and Table 2 shows data for single reinforcement with steel rods from 10 to 16 mm.
Material, per 1 m2 of floor |