Reinforcement of the rough floor screed on the ground. Proper reinforcement of the floor slab on the ground. Hydro and thermal insulation device

During the construction of a private house or during overhaul the question of reinforcing the screed inevitably arises. Anyone who wants to save money does only concrete screed, and someone wants to create a surface "for centuries" using concrete floor reinforcement.

Depending on the purpose and location, the construction of a concrete floor can be divided into several types:

  • rough screed resting on the ground or slab;
  • leveling screed (self-leveling floor);
  • construction based on floor slabs;
  • screed with layers of heat and sound insulation.

Reinforcing floors made of concrete is advisable in cases of formation and with a multi-layer screed with a layer of thermal insulation. Reinforcement in such cases is simply necessary, since the floor is not arranged on a fixed (monolithic) basis, and tensile and bending loads act on it.

Reinforcement can be used to reduce if the calculations assume that its layer is too thick. There are several types of reinforcement. The appropriate one is selected according to the project and operating requirements only after the calculation has been completed. Make your own calculations, taking into account all building codes, is rather difficult, and the probability of error is high. Therefore, to resolve this issue, it is better to use the help of design organizations.

Used to reinforce concrete floors the following constructions and materials:

  • reinforcement cage;
  • mesh made of wire rod;
  • mesh welded with cells from 50-200 mm;
  • fiberglass mesh;
  • polymer mesh;
  • special additives for fiberglass concrete.

Regardless of the method of reinforcement, work to strengthen concrete floors must be done according to certain rules.

Types of reinforcement based on the characteristics and purpose of your floor.

  1. Before pouring, the reinforcement material must be strictly distributed over the surface of the construction site using props (except for fiberglass additives).
  2. Reinforcement should not interfere with the distribution of concrete.
  3. The concrete and the reinforcement material used must have good adhesion. To do this, contamination with oily substances should be avoided.
  4. To avoid corrosion, rotting or oxidation, the concrete must completely cover the reinforcement.

Frame or monolithic reinforcement is necessary in cases where the foundation and floor of the house are a single system for holding the building, or when reinforcement is necessary on the basis of calculations or due to the unreliability of the soil on which the house will be based. In this case, the construction of the entire structure must be carried out taking into account the following indicators:

  • reinforced concrete structure thickness - more than 100 mm;
  • the height of the reinforcement frame is more than 50 mm.

Monolithic option

With this method, the reinforcing frame is built from reinforcement. The fittings used can have a diameter of 6-40 mm. It depends on the project or the required strength of the structure. Reinforcement of concrete floors of private houses in most cases is carried out with reinforcement having a diameter of 10-20 mm.

The reinforcing mesh is “knitted” with a steel wire 2-3 mm thick. Moreover, during its formation, cells with dimensions of 100-200 mm are made.

Then several layers of mesh (mostly two) are attached to the lifting ribs. It is better to use whole pieces of reinforcement for work, both in length and in width. If the consumption of reinforcement is too high, then trimmings can be used, but at the same time, the fastening is overlapped with an overlap of at least 0.5 m. Then the reinforced frame is poured with concrete.

Welding can also be used to form a frame from reinforcement. But for the production of such works with your own hands, you need to have welding machine and work experience. Disturbed work technology often leads to thinning of the reinforcement at the joints.

Reinforcement with meshes

Less complex type reinforcing the floor structure is a reinforcing mesh made of wire. In this way, it is possible to reinforce a concrete floor having a thickness of less than 80 mm (used to form a multi-layer base on the ground or to reinforce a floor screed in places subject to special loads, for example, in a bathroom, kitchen, garage or hallway). The reinforcement system practically does not differ from monolithic reinforcement. The result - the grid installed at a height of 20-30 mm is poured with a concrete solution.

Mesh execution can be both welded and knitted. There are also ready-made metal meshes for reinforcement. It will be enough to lay them in a layer on the floor surface with an overlap of 1-2 cells and tie them with wire. The cost of such a grid in monetary terms is not much higher than with self-manufacturing. This saves time and increases reliability.

Polymer nets

The use of polymer mesh is one of the most simple ways reinforcement. This method is often used not to strengthen the floor structure, but to prevent cracking of concrete during drying and with small deformations. The mesh is installed directly on the floor base, especially if it is covered with a film located on the embankment (cushion) or on thermal insulation to prevent cracks from appearing on the back of the screed.

Polymer meshes are widely used for reinforcing poured concrete floors. This is due to the ease of installation and technological features poured floors. The formation of floors using polymer meshes significantly reduces the volume required concrete and the thickness of its final layer.

Additives for concrete

Today, in construction, the use of fiberglass, which is a polymer fiber with a thickness of about 15 microns, is becoming increasingly popular. When added to concrete, the screed layer is strengthened and the appearance of microcracks during drying is prevented.

Even with small violations of the conditions proper drying and the formation of microcracks is significantly reduced.

In this article, we will analyze in detail the design and construction of a monolithic concrete floor on the ground. Under the "floor on the ground", further in the article, we will understand the concrete floor, made inside the contour of the foundation, right on the ground. Consider FAQ associated with this floor, and the structure itself from the ground to the finish coating.

With what types of foundations can you make a floor on the ground

The concrete floor on the edge can be used for strip foundation, and with a columnar foundation (or a foundation using TISE technology). slab foundation itself (by its design) is immediately a floor on the ground. With a strip foundation, the floor structure, as a rule, adjoins the foundation wall.

Rice. 1. Adjoining the floor on the ground to the strip foundation


Rice. 2. Adjoining the floor on the ground to column foundation with a low grillage

With a columnar foundation or a foundation using TISE technology, the floor structure on 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, they are not removed, Figure 3.


Rice. 3. Adjoining the floor on the ground to the columnar foundation in the case of a high grillage

The height of the floor device on the ground relative to the strip foundation


Rice. 4. Floor on the ground on the tape extension


Rice. 5. The floor on the ground is adjacent to the wall of the strip foundation


Rice. 6. The floor on the ground is located above the foundation tape


Rice. 7. Floor on the ground adjacent to the top of the tape

There are no constructive mandatory recommendations regarding the mark (height) of the floor device on the ground. It can be arranged 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 front door will be in height. 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 need to then cut an opening in the tape under the door.


Rice. 8. Height difference between the floor on the ground and the doorway


Rice. 9. Floor on the ground flush with the doorway

Note: opening under front door it is better (more correct) to foresee at the stage of pouring the tape. Just do not flood this place, insert boards or polystyrene there, so that an opening remains in the tape. If you forgot to leave the opening, then you will either have to make the entire floor higher (and this will increase the cost of backfilling), or cut an opening in the finished tape, cut the reinforcement in it, loosen it, etc.

Thus, if the opening under the front door is made correctly (at the stage of pouring the tape), then we arrange the floor on the ground so that the top of the floor is flush 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 from what mark you need to start its construction, you need to understand what all its layers will be in thickness, what it depends on. More on this later.

There are no such cases. Even when the groundwater level is high, it is more correct to arrange a monolithic floor on the ground than a floor on logs, for example. The type of soil, seismic, freezing level - all this also does not affect the possibility of constructing such a floor.

Note: We do not consider situations when the house is raised above the ground on piles, it is clear that then such a floor is not suitable.

Floor construction options on the ground


Rice. 10. Floor construction on the ground at ground water level higher than 2 m (with waterproofing)


Rice. 11. Floor construction on the ground at low groundwater level, below 2m, with backfill


Rice. 12. Floor construction on the ground at low groundwater level, below 2m, without filling, with pouring instead of a rough screed


Rice. 13. Floor construction on the ground at low groundwater level, below 2m, without filling, with a rough screed


Rice. 14. Floor construction on the ground in combination with a warm floor

Note: Figure 14 shows underfloor heating pipes and a reinforcing mesh above them. Between the floor pipes and the reinforcing mesh, - no gap, just drawn for clarity.

Description of the main layers of the floor on the ground

Let's analyze the main layers (pie) of the floor on the ground. We consider the design from the bottom - up. We will describe all the layers that may be, without reference to a specific pattern.

  • compacted soil- the basis for the device of a floor, has to be qualitatively condensed;
  • Backfill layers(sand 7-10 cm and gravel 7-10 cm). Backfill layers can be made to protect against capillary rise of water and can be made as a leveling layer. Crushed stone in the bedding layer should be of a fraction of 30-50 mm (large). The sand in the bedding layer can be any, both river and quarry (ravine). It depends on the purpose for which the backfilling is done, whether it is possible to replace crushed stone with expanded clay, 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 layers of backfill are well compacted. There are conditions when a bedding device is mandatory, and when it is not. You can read about this in the paragraph What determines the design of the floor on the ground, in the same article, below;
  • Rough floor screed on the ground. This is a layer on top of the bedding or compacted soil. Executed by polyethylene film(it spreads on the ground or bedding), the thickness of the rough screed is 5-7 cm. It can not be reinforced. Sometimes rough screed replace with a spill. About spilling - in the next paragraph, about when it is possible to replace a rough screed with a spill - in the paragraph Is it possible to replace a rough screed with a spill, in the same article, below. Crushed stone in the design of the rough screed should be a fraction of 5-10 mm (fine). The sand in the design of the rough screed must be river, not quarry (ravine);
  • Spilling (filling) the floor on the ground. It is arranged by spilling a layer of bedding with a solution. The thickness of the pouring is equal to the thickness of the bedding layer. It is arranged without a plastic film;
  • Waterproofing. It is arranged from roofing material, 1-2 layers. Roofing material can be taken the most common, without sprinkling. There are conditions when waterproofing is required. You can read about this in the paragraph What determines the design of the floor on the ground, below;
  • . We recommend using EPS with a density of 28-35 kg / m 3, or polystyrene with a density of 30 kg / m 3 and higher as a heater for the floor on the ground. The thickness of the insulation is determined by calculation (depending on the climatic zone);
  • Finishing screed. Thickness finishing screed 7-10 cm. Crushed stone in the construction of the finishing screed should be a fraction of 5-10 mm (fine). The sand in the construction of the finishing screed must be river, not quarry (ravine). A finishing screed (unlike a rough screed) is necessarily reinforced. Reinforcement is carried out 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. Finishing floor covering on the ground can be any. Accordingly, the details of the device are different for each type of coverage.

The presence and sequence of floor layers on the ground

What determines the design of the floor on the ground:

  1. From the level of occurrence of groundwater;
  2. From whether these floors will be with heat carriers (warm) or not;
  3. From operational loads on the floors.

How exactly the construction of the floor on the ground depends on these factors, we will analyze below.

1. By the presence of waterproofing. Our recommendations: to arrange waterproofing from roofing material (1-2 layers), if the groundwater level lies closer than 2 m from the bottom of the floor along the ground. In addition, when the groundwater is located closer than 2 m, we recommend that you make sure to add sand and gravel, Figure 10. If the level is lower than 2 m, then you can make the floor without waterproofing. At a level lower than 2 m, sand and gravel filling is not required, Figure 11, 12, 13.

Note: You need to focus on the highest level of groundwater that can be on a particular construction site. That is, to watch how high the water rises in spring, during floods, etc., and this is the level to take into account.

2. If there are heat carriers in the floor structure on the ground, it is necessary to make a gap between the walls and the floor, 2 cm. This requirement is the same for both water and electric underfloor heating. The gap is made at the level of the finishing screed (with coolant). All layers below the finishing screed are placed to the walls without a gap, Figure 14. You can read more about installing a water-heated floor in the article.

3. If it is planned that something heavy (heavier than 200 kg / m 2) will be placed on the floor on the ground, then we reinforce the finishing screed with a mesh with a wire diameter of 4 mm. If the load is up to 200 kg / m 2, then it can be reinforced with a wire mesh with a diameter of 3 mm.

Important points when installing a floor on the ground

These important points I would like to sort it out on the basis of questions that, as a rule, readers of our portal have when installing a floor on the ground.

Can interior walls be placed on this floor?

Yes, it can be placed on a 4 mm wire-reinforced screed internal walls from brick (to brick), from a partition block (100 mm), and a wall half a block thick. By "block" is meant any block (expanded concrete, shell rock, aerated concrete, foam concrete, etc.)

Can crushed stone in the bedding layer be replaced with expanded clay?

Backfilling is performed, as a rule, in order to break the capillary rise of water. Expanded clay swells from water, and, as a bedding material, is not suitable. That is, if the bedding was planned as additional protection from water - such a replacement cannot be done. If the backfill was planned not as a 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 crushed stone can be replaced with expanded clay for flooring on the ground.

Can crushed stone in the bedding layer be replaced with broken bricks, building materials waste?

It is forbidden. If the bedding was planned as additional protection against water, then broken brick and other waste will not fulfill their task in the bedding. If the backfill was planned not as a protection, but simply as a leveling layer, then we also do not recommend such a replacement, since these materials are of different fractions, it will be difficult to compact them with high quality, and this is important for the normal operation of the floor structure.

Is it possible to replace crushed stone in the bedding layer with expanded clay, pour more of it, and then not put insulation?

To replace 50-100 mm of EPPS (that's how much on average is needed to insulate the floor on the ground), you will need 700-1000 mm of expanded clay. Such a layer cannot be compacted with high quality, so we do not recommend doing this.

Is it possible not to reinforce the screed?

You can not reinforce the rough screed. It is imperative to reinforce the finishing screed.

Is it possible to reinforce the screed with a non-mesh? Is it possible to put just metal bars in the screed instead of a reinforcing mesh, without tying them together, or other metal parts?

No, in order for reinforcement to work, it must be performed by a mesh.

Can waterproofing be laid directly on the layers of backfill?

No, the waterproofing must be laid on a flat and solid foundation(in our case, this 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 layers of backfill?

For waterproofing dismantled in the paragraph above. Insulation must also 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 spill instead of a rough screed?

Let's analyze what we mean by "rough screed" and "pouring". A rough screed is a layer on top of the bedding or compacted soil. It is carried out on a polyethylene film (it spreads on the ground or bedding), the thickness of the rough screed is 5-7 cm. The thickness of the pouring is equal to the thickness of the bedding layer. It is arranged without a plastic film. Now about whether it is possible to replace the rough screed with a spill. If the water is closer than 2 m, and the bedding (sand and gravel) was carried out as a layer that prevents capillary rise, then watering cannot be done. Because the spilled rubble will not cut off 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 do the spill instead of the rough screed. If there is no backfill at all, and the screed is carried out directly on the compacted soil, then both a rough screed and a spill can be done. It only turns out that it makes no sense to do the spill, since for it you still have to pour sand about 3 cm and crushed stone about 10 cm, and the sand in this case is river, and the crushed stone is about 10 mm fraction. In general, it is easier to perform 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 layers of backfill or into the ground. This layer is purely technological, it does NOT replace the main waterproofing (roofing material over the rough screed). If the water is deeper than 2 m, then waterproofing (roofing material) is not needed, but this does not mean that we “replaced” it with polyethylene. It's just that these layers have a different function, 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 it correct to place the reinforcing mesh in the finishing screed?

Does it matter where exactly the reinforcing mesh is located in the finishing screed layer (bottom, top or center)? If the screed is without heat carriers, then the mesh should be located 3 cm from the top of the screed (that is, approximately in the middle). If the screed is with heat carriers, then the mesh must be on top of the pipes, plus 2-3 cm of the protective layer.


Rice. 15. Finishing screed without coolants, reinforcement


Rice. 16. Reinforcement of the finishing screed with coolants

When arranging the main floor in private buildings, in warehouses or in trading floors, a rough floor screed is popular. It can be arranged regardless of what kind of soil is under it, as well as the possibility of being in the groundwater zone. All requirements for the use of materials and surface preparation are prescribed in the design and estimate documentation. At self-fulfillment work must adhere to technology in order to get an excellent result.

Device diagram

If we take into account the location of the floor to such factors as the level of the soil, the foundation, the location of the groundwater zone, then certain options can be distinguished that allow the installation of the screed:

There is no way to choose any universal way arrange . The main condition here is that you should first plan the location door frame and only then proceed with the installation. The threshold level must match the level of the poured screed (top coat).

Ground Options

No builder has classic version pouring a rough floor screed, and approach the choice depending on the specific conditions. The optimal one is soil that is carefully compacted, a layer of sand, a layer of crushed stone (sand and crushed stone should have different height). Subsequently, a polyethylene film is laid and the screed is installed in a draft form. Reinforcement is not always used and also comes from individual indicators.

The circuit can be simplified if ground water located below two meters from the ground. Pouring a rough screed can even be carried out directly on the ground. Concrete is not afraid of moisture, therefore, the film in this case contributes to the retention of cement laitance. Strength in this case will increase markedly.

Training

A very important and initial stage is to carry out activities to study the base where the subfloor will be performed. It should not have bright protruding elements or depressions. They have to be dealt with. After that, marking work is carried out when optical or laser levels are used.

In this case, a zero mark is set, the level of the floor surface, the relief is determined. If you do without tamping the soil, then in the future you may encounter subsidence, which will affect the state of the arranged screed. Tamping also allows you to avoid the appearance of cracks on the surface of the subfloor, its cracking with the ensuing consequences.

The completed screed is the basis for subsequent masonry floor covering any kind. But at the same time, it serves to level the surface, creating a hard layer. If desired, it can mask any kind of communications in the building.

It is possible to compact the soil on their own. But it is very problematic to achieve a positive result and energy-consuming. The optimal case is the use of special equipment (ramming machines).

Then it is poured on a layer of soil river sand certain thickness. The selected layer is different from the one that is poured onto the surface. The latter should be about a quarter larger. This is all done for the reason that river sand is moistened and compacted by special machines (skating rink, vibro-rammers). As for special equipment, everything will depend on financial opportunities. With their help, you can perform any amount of work with high level quality, but even the cost of rent is quite high.

To compact the sand base, an additional layer of expanded clay or gravel can be poured. Everything will depend on the final layer of the rough floor screed, the base errors.

Waterproofing

When filling the subfloor in the house, it is not enough to arrange only the base and proceed with the installation. In addition to this, other very important layers should be organized. Among them, one of the most important is the waterproofing layer.

Laying waterproofing on the floor serves to protect against the ingress of moisture from the concrete screed into the base, as well as the reverse process - pulling moisture from the existing soil. As a material for the device of this layer, polymer membranes or bituminous materials in rolls are used. Another alternative to the materials described above is a thick polyethylene film. All this can be easily purchased at any hardware store.

Waterproofing can be arranged only on a solid and even base. This will save the service life. Therefore, it is necessary to qualitatively compact the soil and the layers of the fill.

The selected material should be placed on the base with sheets with an overlap of 10-15 cm. The sheets are joined together using construction tape. We must not forget about the institution of a layer of waterproofing on the wall to a height of 15-20 cm. You should not be afraid to make a larger flooring, since later the excess is removed without problems. Waterproofing the concrete floor is mandatory to achieve the desired result.

Reinforcement and beacons

When waterproofing was dealt with without problems, you can think about high-quality reinforcement of the future. This will increase the strength characteristics of the floor. As a material, a reinforcing mesh is usually chosen, having cells with a step of 50 * 50 or 100 * 100 mm. The thickness of the rods in the grid is within 5 mm. All the necessary reinforcement parameters for a rough screed can be found in the store, where everything is implemented with a complete set for work. An alternative to steel mesh is a polymer mesh, which has a much lower weight, which is very important when installing a screed on floor slabs. Here you will need to comply with the requirements for the maximum weight of the finished structure.

We must not forget that the metal mesh should not be laid directly on the base, since in this case it will not bring the desired result. It is usually located on special elements in the form of a poured mortar or concrete fragments, approximately in the middle of the thickness of the future rough screed.

Technology does not stand still. Pouring a rough screed can be done using together steel mesh. Fiber allows you to noticeably reduce total weight used in the work of the solution, and also gives it certain additional properties and qualities, which include high strength and excellent ductility. All this helps to get rid of the possible appearance of cracks on the surface, shrinkage after complete drying. In addition, the cost of using such a material in a solution will be somewhat lower than a steel mesh, when calculated per meter. square square premises. The final choice will depend on the artist.

The future rough screed will turn out to be more even and practical if you set the beacons correctly in terms of level. They can be performed different ways and options. The most common are special profiles, called beacon profiles. They are fixed to the base on cement protruding elements from the finished solution.

Ground screed installation

For mounting the screed, you can independently prepare the solution, observing the proportions of all the components used. If there is no time and desire to spend energy on this event, then you can order from construction companies in the right amount. When there is a limitation in financial plan, then it is necessary to make calculations in each individual case and decide on a specific option.

The density of the mixture for a rough concrete screed should be medium. This will allow it to spread over the surface on its own and require virtually no leveling effort. In this case, you can even do without beacons.

When the concrete subfloor is poured, you can start caring for it. For several days, the surface requires moistening for quality and strength characteristics. In the next two weeks, concrete will be able to gain about 50% of the strength of the maximum. This allows you to continue to carry out all kinds of construction works. Floor screed on the ground is not particularly difficult. The main thing is to follow the technology of mounting the screed and perform all the steps in sequence.

FAQ

When performing work, the main thing is to understand how to properly fill the subfloor. There are subtleties and nuances here. It will not be superfluous to answer some questions of interest that will avoid difficulties in the process.

Is it possible to replace crushed stone with broken brick, other construction waste?

Answer: By no means. Crushed stone, unlike broken brick, is able to protect the rough screed from excess water. Expanded clay is also not suitable for backfilling in this case, as it will begin to swell from moisture. Even if protection from moisture is not required, it is difficult to compact broken bricks due to the different fractions of the elements.

Is it possible not to reinforce the rough screed?

Answer: Mandatory reinforcement is provided for the finishing layer of the concrete screed. Therefore, this layer can be dispensed with under certain conditions.

Is there enough waterproofing layer under the rough screed?

Answer: Under the rough screed, a film of polyethylene or other material only helps to retain the milk in order to obtain a better strength of the solution during the drying process. A waterproofing layer is also required after installation, before laying the finish layer.

Which optimal location reinforcing mesh?

Answer: The approximate distance from the base of the location of the metal mesh in the thickness of the concrete screed is 30 mm. But you should focus on the total thickness of the fill and place a layer of reinforcement in its central part.

Despite their high strength, concrete screeds may need additional reinforcement. This is relevant in conditions of high mechanical loads, when pouring unrelated structures, in case of shrinkage and deformation of concrete.

Reinforcing concrete floors are not always implemented. But, reinforced structures win 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 device of a reinforced concrete floor is reasonable in order to protect the structure from mechanical pressure, vibration loads. In general, we can talk about long-term operation.

When a reinforced concrete floor is laid:

  • if the project will lay a floating screed. This issue is especially relevant in the presence of loose substrates, in the presence of a large number 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 heat-insulating layers based on expanded clay;
  • current building codes and regulations dictate mandatory reinforcement in underfloor heating systems. Without reinforcement, such structures are more susceptible to deformation, due to constant temperature changes;
  • concrete flooring is always reinforced in industry, especially in areas with high traffic and under heavy equipment.

Reinforcement is a mandatory stage of work with a concrete layer height of more than 50 mm

Materials used

When pouring concrete screeds, only those reinforcing materials are used that are approved for use by the current rules and regulations.

This group includes:

  • steel meshes (reinforcing, wire);
  • fiberglass - for bulk reinforcement;
  • fiberglass meshes;
  • grids based on modern polymeric materials.

Certainly the most durable structures created on the basis of metal fittings. They have been successfully used in industrial premises, in garages, warehouses, open street areas. The solution is suitable for the installation of screeds on the ground.

Fiberglass and polymers are optimally matched to the requirements of underfloor heating screeds. They are not suitable for the construction of structures on the ground. Such materials are light, do not give an additional load on the overlap, but do not work well for breaking. It can be said that this perfect solution for places with small loads.

Volumetric strengthening with fiberglass provides protection against shrinkage deformations, 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.

The nuances of reinforcing concrete floors

For concrete floor structures, which will account for high and ultra-high loads, it is better to choose metal reinforcement. The diameter of the bar is determined depending on the operating conditions and loads. In practice, this is 6-12 mm. The most common cell size is 10*10, 20*20 mm.

Reinforcing mesh can be bonded in single system knitting wire or by welding. Both options work successfully in screeds on the ground. Current regulations Allow installation of a grid in two layers. The cost of reinforcement depends on the mesh size, material consumption, and bar diameter.

Finished wire mesh is available in sheets and rolls. The basis is a wire of class VR-1 and d 2-6 mm. The material is suitable for the device of rough screeds in conditions of moderate loads. Cell dimensions can vary within 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 delamination, dirt, dust;
  • the detected cracks need to be expanded, dedusted, treated with soil and repaired with a repair mortar;
  • the base is primed in 2-3 working approaches;
  • hydro and sound insulation flooring is carried out with gluing of overlaps and access to the walls;
  • marking is carried out using the level;
  • the reinforcing mesh is laid on stands so that the material is in the concrete body, observing an overlap of one cell;
  • 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, alignment is carried out using the rule;
  • when the concrete has set, the guides are dismantled, 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 meshes

If a concrete structure it is arranged on floor slabs and too high loads are not expected, it makes sense to turn to plastic reinforcing meshes. This is the optimal solution for strengthening screeds up to 80 mm thick, including when implementing self-leveling systems and underfloor heating.

The advantages of such materials are much lower mass compared to steel, high elasticity. Plastic is able to stretch, which works to preserve the integrity of the structure under the action of shrinkage processes.

The material is sold in rolls, at an affordable cost (from 120 r / sq.m.). You can count on convenient transportation, installation, cutting. Plastic is not subject to corrosion, 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 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 aluminoborosilicate glass.

If we talk about the benefits, they are identical to their polypropylene counterparts. The scope of application is the same as plastic nets. Fiberglass is an easy to carry, lightweight, elastic material, but it does not withstand the action high temperatures(limit 200 degrees) and is not suitable for areas with an increased risk of fire.

Features of bulk 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 has gained strength, a monolithic coating is formed, which is minimally prone to cracking.

The choice of material type is based on the purpose of the screed. So, for lightweight structures, polypropylene and fiberglass are required. For higher loads, it makes sense to pay attention to metal varieties. If the structure is to be used in difficult conditions or at outdoors, apply basalt fiber.

When mixing the solution, the fiber is filled up 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.

Concrete floor works

The device of the concrete floor is implemented using the following technological operations:

  • pouring a reinforced concrete slab of the appropriate thickness, or compacting the soil, installing a sand and gravel cushion;
  • reinforcement in one layer;
  • pouring concrete along guides, class not lower than B22.5. Guides are arranged using an optical level. Alignment is realized by an aluminum rule (5-7 m). Without guides, they work on liquid beacons using a vibrating screed. The sealing of the screed is realized by deep vibrators;
  • grouting is carried out by concrete trowels 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 the hardening of the solution is removed. Work is carried out 3-6 hours after laying the solution at t not lower than +20 degrees;
  • the second grouting and smoothing with the blades of the trowel to a mirror finish;
  • distribution of roller care products;
  • filling the seams with sealing profile materials.

It is necessary to cut expansion, temperature-shrinkage seams with a cutter to a depth of 1/3 of the thickness of the structure

Detailed list of works

The compacted soil base is filled with sand. The average layer thickness is 200 mm. Layer-by-layer compaction with vibrating plates is carried out. The sand must be compacted in accordance with the design marks, which is controlled by a level. Another technology involves the construction of reinforced concrete slabs.

Installation of formwork, guides

Concrete floor is being laid separate sections- cards. These are rectangular zones of the required size. The actual parameters of the pour maps depend on the total surface area and the ability to lay mortar in one work shift.

Along the perimeter of the cards, formwork is installed under the mark of the finishing floor. Material - wooden plank 50*100 mm. In the boards, holes should be pre-drilled for the reinforcement pins in increments of 50 cm. The formwork lines should overlap the pattern of expansion joints.

If the installation will be carried out along the guides, they are arranged on the basis of metal profiles, or a steel corner 50 * 50 * 3 mm, or a profile pipe 40 * 20 * 2 mm.

Guide rails are welded to rebar posts with a diameter of 12 mm. Evenness is controlled by an optical level. All places where the surface adjoins load-bearing structures pasted over damper tape based on polyethylene foam, for example, Izolon 4 mm thick.

Profiles should be treated with engine oil before filling. The rough base is moistened with water.

Reinforcement

AT concrete floors reinforcement is carried out in accordance with the project, based on the expected loads. You can use a welded road mesh with a diameter of 4 mm, a cell size of 20 * 20 cm. The material is laid in one layer, overlaps are provided. Reinforcement clamps are mounted - chairs to ensure protective layer in 20 mm.

All overlaps are fixed with a knitting wire with a diameter of 1.2 mm. Overlaps and protective layer are checked. Before laying the reinforcing mesh frame on the base, it is recommended to put a polyethylene film. This will reduce moisture loss from concrete mix and provide waterproofing.

If the project requires laying a 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.

Upper - mounted on special strip clamps, taking into account gaps in the areas of shrinkage and technological seams. For work, strip fixators FP 60-4.0 are taken. They are connected to the mesh with a tie wire and provide a protective layer of 25 mm.

Concrete laying

When laying concrete according to the maps, there should not be long technological breaks, that is, more than 60 minutes

After the installation of reinforcement and formwork, it is the turn of pouring the concrete mixture. The choice of material is based on the type of construction, method of installation and transportation. When working on floors, a class not lower than B22.5 is applied.

If the area and working conditions do not allow the mixer to drive close to the object, concrete pumps are used. With a small amount of work, concrete mixers are used. The filling must be continuous, otherwise the risk of cracking is high.

In order 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

Compaction of the solution is carried out by deep vibrators. For leveling along the guides, a rule is taken. Work with the surface is carried out in 3 technological approaches. If the concrete shrinks, the mortar is added with a shovel in the required quantities.

Control over the correctness of laying is implemented using a level, which corresponds to SNiP 3.04.01-87.

If the guides were planted on liquid beacons, they act as deep vibrators and vibrating screeds. The work is carried out in 2 working approaches. With this technology, plasticity and workability of the solution are required, for which it is recommended to introduce plasticizing additives C-3. Concrete is laid and leveled so that the top is slightly above the level of the screed. Next, the tool is pulled along liquid beacons.

Under the action of vibration, the solution settles to the required level and is leveled. But, it is required to ensure that the tool constantly slides over the surface. If the 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 it will be possible to safely step on its surface without leaving marks deeper than 3 mm. They start processing with a trowel with disks in several technological approaches. Where concrete adjoins building envelopes, 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, a dosing trolley is taken and dry topping is applied. Quantity - 50-60% of total expense. On average, it is 1-1.5 kg/sq.m. The total consumption is in the range of 2.5 kg/sq.m., but may increase equivalent to an increase in floor loads.

When the composition absorbs moisture from concrete slab, which can be traced by darkening, the first grouting is carried out by concrete finishing machines with a disc. Work begins near walls, columns, doorways . Work is continued until a uniformly mixed mixture is formed on the surface.

Topping should be completely saturated with cement milk and connect to the surface

Second application of hardener

When the first grouting is completed, the remainder of the mixture is spread immediately. This will allow the topping to absorb the moisture from the laitance before the water evaporates. The application is carried out in such a way as to compensate for the possible uneven application of the first layer.

When moisture has been impregnated, which is traditionally traced by darkening, proceed to the second grout. They work until the topping is completely saturated. If additional compaction is required, the treatment can be duplicated.

smoothing

Finishing grout is realized by blades. Based on the state of the surface, the interval between approaches is determined. The concrete should become opaque without getting your hands dirty when touched. Work is completed when a smooth, even surface is formed.

Now you can cover the concrete with polymer compounds. The material is applied with rollers. This will prevent too rapid loss of water.

Cutting of thermal shrinkage seams

For 2-3 days after completion of work, shrinkage and technological seams should be cut. To determine the readiness of concrete for work, a trial cutting is required. The edges of the seam should not crumble and be painted.

Seams are required to compensate for shrinkage and temperature processes occurring in the structure during concrete hardening. Plus, they prevent linear thermal deformations that occur during operation.

Joint cutting map: from 2.5*2.5 m to 3*3 m. The pattern must match the axes of the columns. In the area of ​​​​the columns, the cutting is made in the form of a rhombus. They act in such a way that the glass of the column is located inside the rhombus. Cutting depth - 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 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, 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 a large amount of work.

The quality of the mortar, the presence and type of reinforcement affect not only costs, but also General characteristics 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 unnecessarily reinforced reinforcement will increase the load, and with the slightest error, this will lead to a loss in the durability of the coating.

The presence of upper reinforcing layers has a very significant effect on the cost of the floor.. But against the background of such costs, the durability of the system increases.

Layers protect the floor from excessive moisture, mechanical damage

conclusions

The quality of the concrete floor is directly dependent on the quality of the concrete. Choosing the optimal solution, they are guided by the strength, durability, moisture resistance of the material, therefore, work on the construction of the structure begins with the choice of concrete class, as applied to each specific object. It is important to organize proper training, backfilling and tamping of the lower layers of the structure.

If we talk about reinforcement, the rule applies here - a lot does not mean good. The reinforcement system must be designed taking into account the operational loads and working conditions. Otherwise, you can count on excessively high costs and excessive loads on the base.

Otherwise, the production of concrete floors requires the participation of conventional building materials and equipment: concrete mixers (if not ordered finished material), brushes, rollers, shovels, polyethylene films, reinforcing additives, etc.

The process of reinforcing the floor under a concrete screed is shown in the video:

The rough floor screed on the ground is laid under the finishing one, therefore, flaws are allowed with it and it may not have an absolutely flat surface. A rough screed is poured to level the differences in the base of the floor along the ground and to prepare a finishing one. The finished floor on the ground without screed is the first coating that serves the same purpose.

Floor device.

How to make a rough screed with your own hands

To properly make a rough floor screed on the ground, you must follow the instructions:

  • is first determined highest point and beacons are set along it;
  • the floor is being prepared for pouring;
  • the solution is being prepared;
  • the solution is poured;
  • when the rough screed is ready, you need to follow it until it hardens.

Rules for installing beacons

Draft wet floor on the screed.

Debris must be removed from the area before starting work. After that, you can proceed with the installation of beacons according to the following sequence:

  • piles are placed on the wall in one line cement mortar with a step of 0.5-1 m from each other;
  • then beacons are installed on the heaps, it can be a metal profile or a pipe;
  • putting the profile on the heap cement composition, it is slightly pressed to the ground, drowning in a solution; having brought the level to the desired height, that is, until a single plane is formed, the lighthouse is fixed with several more portions of cement;
  • the required height of the beacon - when its highest point is on the same level with the screed;
  • to make the alignment of the first lighthouse easier, two self-tapping screws are screwed into the place of their connection and a fishing line is pulled over them; subsequent beacons can be straightened along this line.

After installing the first beacon, all the others are set in the same order. If the installation went correctly, then the last profile should be opposite the first.

Preparatory stage

Types of subfloor device.

In order for the adhesion of the screed to the base of the floor to be sufficient, a number of preparatory measures should be carried out.

  1. The first stage of preparation is alignment. If there are cracks, holes, irregularities in the base, then they are sealed with a solution.
  2. The second stage is cleaning. The place where the screed will be laid is cleared of debris and dirt.
  3. After cleaning, the surface is primed for better adhesion.

While the screed is being laid, all holes must be sealed with plugs. Before hiding pipelines and other engineering Communication, they should be attached to the floor with dowels, wrapped in front of this isolon. A rough floor screed on the ground is an economical design. The components of the solution itself are inexpensive.

Completion of the rough screed

Scheme of subfloor construction on a combined screed.

Typically, the solution is prepared in a ratio of 1 to 3 (cement and sand, respectively). For 1 kg of dry mix, usually take 0.5 liters of water. If the specified proportions are not observed, then the composition will not come out as strong as required. Subject to all the rules, the mixture should be homogeneous and plastic in consistency. To prepare it, you need the following tools:

  • shovel;
  • buckets;
  • suitable container;
  • concrete mixer;
  • robe.

Next, the process of laying the screed begins. The space between two nearby lighthouses is filled with mortar with a shovel. When the profiles are covered with a mixture, it is necessary to take the rail and, putting it on the beacons with both ends, remove it with wave-like movements upper layer solution to the mark. If voids begin to form under the rail or rule, then the solution is reported in them and leveled again. There are several professional tricks to make the screed more even:

  • in order to avoid displacement of the beacons during pouring under them, all empty spaces must be filled with mortar in advance;
  • it is better to prepare cement in several passes in order to have time to fully use it before it hardens;
  • it is better to pour the screed in one day so that the surface is homogeneous, without cold bridges.

How to monitor the screed in the early days

The device of a dry subfloor on the logs on the floor slab.

During the drying time, the screed shrinks, so you need to look after it. The first days of drying do not walk on it. The room where the screed is laid should be darkened and closed to prevent drafts. All activities are aimed at creating the same microclimate throughout the room, so that the evaporated liquid is distributed evenly everywhere. A day later, the screed is covered with a film and waiting for its complete hardening. This will take 2 to 5 days. It all depends on the thickness of the layer.

If a rough screed is used to level the floor on the ground, then some irregularities are allowed. If the floor on the ground is planned to be warm, then the rough screed should be leveled. This is due to the fact that heating element floors on the ground are placed between the screeds, and if the rough screed is not leveled, then the main floor screed will turn out with height differences at various points, that is, the heating of the room will be uneven.

A rough floor screed on the ground is an economical option, but very laborious, that is, the materials for such work are inexpensive and it is not a problem to buy them, but the work process itself is long and rather difficult. When laying a layer of cement-sand mortar, sand is poured under it and rammed. After tamping, the floors are covered with rubble. If you pour the screed on a layer of rubble, then it will not settle or crack over time.

Concrete parameters

Comparative characteristics of base concrete.

The floor on the ground is designed mainly for country houses and cottages, as it is believed that this is the most economical and reliable option. In the context of the floor on the ground is a layer cake. First, a layer of earth cleared of grass is taken and the sole is prepared from it. Sand is poured on it, set waterproofing film, pour a rough screed, which includes a reinforced metal mesh. After that, the materials for insulation are laid, then a film is again installed to protect against moisture, and finally, a cement-sand screed, on which the floor will rest. Various conditions imply different Constructive decisions, which entails an increase or decrease in the number of layers.

If the building project was conceived with heating with a liquid coolant, then in this case a rough concrete screed with a thickness of 80-100 mm is made on the ground. Wherein cement strainer will have a thickness of 50-70 mm. The floor on the ground with the underfloor heating system does not differ from the warm floor, but has a thinner screed.

It is believed that a rough concrete screed or a cement-sand screed must be reinforced. In construction terminology, this layer is called the underlying layer. In construction guides there are several points about the underlying layer:

  1. Non-rigid subfloor layers made of asphalt concrete, stone materials, selected earth compositions, slag, crushed stone or gravel require mandatory mechanical compaction.
  2. Rigid underlying layer - concrete, reinforced concrete, reinforced concrete - can be made of class B22.5 concrete. If the floors have increased loads directed to the underlying layer, then it is allowed to use class B7.5 concrete. In this case, a screed with concrete B12.5 is performed.
  3. The thickness of the underlying floor layer is determined by the calculation of the loads acting on it in millimeters, for example, for sand - 60 mm, for slag, gravel, crushed stone - 80 mm, for concrete in residential premises - 75 mm; the same in working conditions- 100 mm.
  4. If the concrete underlayment is used as a covering without screed, its thickness should be increased by 20-30mm.

Usually there are no direct instructions for reinforcing the floor on the ground. But in the list of materials there is a reinforced floor on the ground with both concrete and rough screed. This issue is being resolved by design organizations and bureaus.

In addition to the rough screed, the floor on the ground has two types of finishing screed device. Before proceeding with laying the final floor screed on the ground, you need to set its zero level. Usually the floor is leveled on the ground using a laser level gauge.

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