Subfloor on a strip foundation. Proper installation of floors on the ground - nuances of technology

In contact with

Classmates

When planning construction frame house The first step is to choose the type of foundation for the future home.

Among the variety of choices, it is worth paying attention to the one with a monolithic slab.

This type of foundation, with sufficient depth excellent for construction on floating, sandy and peat soils – where other types will not be reliable.

A monolithic slab on a strip foundation is a solid iron concrete structure resting on the base belt type along the perimeter.

In this case, the following options are possible: with the slab supported on the ground, and without support. In the second case, the monolithic slab rests on a strip base, reminiscent of a foundation using floor slabs.

Which is better: strip foundation or monolithic slab? It is impossible to answer the question unequivocally, because both designs complement each other perfectly.

With this type of foundation possible arrangement ground floor or underground garage under frame house. In both cases, this design allows you to connect the strip-type foundation into a single whole.

A monolithic slab on a strip foundation is used:

• during the construction of buildings on unstable, “floating” soils where the use of a different type of foundation is impractical or unprofitable;
• When the structure of the building is intended to be heavy, for example, made of brick or monolithic reinforced concrete;
• When it is planned to construct a single basement floor under the entire building– a monolithic slab on a strip foundation will be indispensable for the construction of partitions in other rooms.

Important! When planning a foundation using a monolithic slab, it must be remembered that maximum length its span in a hanging state should be no more than 6 meters without additional supports.

Construction technology

House without a basement

The peculiarity of this type of foundation is that the slab rests on the ground over its entire area, creating additional support for the building.

A monolithic slab on a strip foundation is constructed with your own hands by pouring a concrete mixture into a prepared pit and includes a layer of heat-insulating material.

1. First of all, a width of 40 cm and a depth of 40 to 70 cm, depending on the type of soil and climatic conditions of the area.

When installing reinforcing mesh, it is necessary leave the ends of the reinforcement sticking out vertically with a diameter of 12–14 mm along the entire length of the strip foundation every 40–50 cm. They will serve to connect the foundation - strip and monolithic slab.

Important! The external formwork should be higher than the foundation being poured to the height of the future monolithic slab - 20–25 cm.

2. After the strip foundation has hardened (1-2 weeks), you need to remove the formwork and prepare the entire internal space for the future slab. A pit 50–60 cm deep is dug manually or with an excavator. The bottom of the pit must be level.

3. A layer of sand is poured 15–20 cm thick. The sand is wetted and thoroughly compacted using a vibrating plate until no traces of shoes remain on the surface.

4. On the sand a layer of geotextile is laid to prevent mixing of sand and crushed stone during foundation operation. Geotextile strips must be sewn together with a special machine. Along the perimeter of the pit, geotextiles should protrude by 40–50 cm and extend onto the strip foundation.

5. Top crushed stone is poured, the layer thickness of which must be at least 20 cm. Carefully leveled and compacted as far as possible. A layer of crushed stone is poured with cement laitance in such a way as to fill all the voids and leave a layer of mortar of 3–5 cm on top.

6. The resulting cake after the solution has hardened covered with a layer of waterproofing. All seams must be carefully soldered with a torch or blowtorch.

Important! ends roll waterproofing should extend to the ends of the foundation by 30-40 cm.

7. Top sheets of heat-insulating material are laid. Its layer should be flush with the level of the strip foundation. It is advisable to use dense grades of penoplex. Joints between sheets of insulation coated with mastic or foamed with a mounting gun.

8. Next stage - styling reinforcement cage . The rods should be 12–14 mm thick, the distance between the rods should be no more than 20 cm.

The mesh is formed in 2 layers, the distance between which is 10–15 cm. The layers are connected to each other by crossbars made from sections of reinforcement. Stands are installed underneath the mesh so that the distance from the bottom row of reinforcement to the insulation is 5–6 cm.

The rods of both rows of reinforcement are rigidly connected to the protruding ends of the reinforcement rods of the strip foundation.

9. The slab is being poured. The process is carried out evenly over the entire area. The level is leveled by outside formwork, but with the condition that the distance to the top row of reinforcement must be at least 5 cm.

Complete crystallization of concrete occurs in 28 days. After this, you can begin building the house. The foundation and slab must be poured simultaneously - intermediate hardening of the layers is not allowed.

Important! Before installing a monolithic slab, it is necessary to lay all underground communications. Joints with heat-insulating material needs to be sealed. The design technology excludes the installation of internal communications after pouring concrete.

House with ground floor

How to pour a monolithic slab on a strip foundation if the building is planned to have a basement?

The manufacturing technology of such a monolithic slab is somewhat more complicated than the previous one, however less material is required due to the smaller thickness of the “pie” of the structure.

1. A strip foundation is being made, identical to that described earlier.

2. A deck is installed at the level of the upper boundary of the foundation. It is a single horizontal shield, usually made of wooden boards.

The deck is supported from below wooden blocks with a cross section of 5*5 cm and a pitch of 0.7–0.8 m. Beams of 10*5 cm are installed on the upright bars. Purlins are placed on top of the beams and secured - 5*5 cm bars.

Deck boards with a thickness of at least 2.5 cm are already laid on them and secured with screws or nails.

Important! The resulting structure must be stable and support sufficient weight.

3. On deck holes are cut and basement communications are laid– heating pipes, sewer pipes, grooves for wires. Right here hatch is installed to enter the basement.

4. Whole area covered with plastic film to protect against dehydration and seal cracks in the deck.

5. Monolithic strip foundation slab: reinforcement- carried out in the same way as in the case of a monolithic slab without a base.

6.Poured concrete mortar , vibrates evenly using deep vibrators. Insulation of such a floor is carried out when installing the floor of the first floor, or directly in the basement.

Important! Dismantling is prohibited support posts and decks until complete crystallization of the cement, which is 28 days, in order to avoid deformation of the structure.

Floor installation

Depending on the purpose, personal preferences and climate, a monolithic floor on a strip foundation can be made in various ways.

Floor on joists

What to do monolithic ceiling on a strip foundation, first on a flat base a layer of waterproofing is laid. It can be roofing material, bitumen mixture or ordinary dense polyethylene.

Then, strictly according to the level, they are installed wooden joists 15*5 cm. If the room is large enough, Wooden spacers should be placed in the center between the joists to avoid deformation of the board.

All free space is tightly filled with insulation. If used mineral wool, it is necessary to lay insulation on top vapor barrier film. When using polymer insulation, this is not necessary.

Plywood is sewn on top of the joists 16 mm thick or floor strip.

Self-leveling floor

A waterproofing film is laid on the monolithic slab. On top is a layer of polymer insulation, preferably polystyrene foam or dense foam grades.

The joints between the plates are carefully coated or foamed.

It is poured onto the insulation cement strainer 3–5 cm thick using reinforcing mesh. On such a base you can lay tiles, porcelain stoneware or self-leveling floors.

With this design it is possible easy to implement heated floors, laying them in a cement screed.

Floor directly onto slab

When implementing monolithic slab technology without a base, when thermal insulation is already included in the base cake, you can lay floors directly on the slab, having previously laid a layer of waterproofing and a special fabric layer, the purpose of which is level out the smallest irregularities in the slab.

Monolithic slab on a strip foundation: technology says that on such a layer with the help of glue you can lay ceramic tiles, and laminate and parquet boards.

Advantages and disadvantages

Advantages of the MZFL slab foundation design:

• ease of installation - can be done alone;
• reliability and durability – service life up to 100 years;
• resistance to ground and surface waters;
• independence from ground movements;
• possibility of arrangement of the ground floor;
• there is no need to build a ground floor floor.

Minuses:

• high cost of materials;
• impossibility of laying additional underground communications without significant dismantling work.

Useful video

What a combined foundation looks like: monolithic slab + tape, is clearly shown in the video below:

conclusions

The foundation is a monolithic slab on a strip base and is rightfully one of the most reliable, durable and justified in construction, especially on unstable soils. Its application in construction frame houses will not only be economically justified, but will also solve many problems during the operation of the building.

In contact with

There are three construction options floor base in a house built on a strip foundation. The first is wooden floors, laid according to load-bearing beams or lagam. The second is a floor on the ground on a strip foundation. The third is a floor slab in finished factory form or poured over a reinforcing frame made of steel reinforcement.

All three designs are often used today, but if we talk about a field on the ground, then it is usually used with a low base part of the foundation, because the space from the ground to the upper ends of the tape must be filled, leveled along horizontal planes.

What is a ground floor

Purely structurally, the structure is a multi-layered cake made of different building materials. Each of them has its own purpose. And the absence of one of them leads to a decrease in quality general design. If we consider the cake from bottom to top, here is the sequence of layers:

Rules for the technology of pouring floors on the ground

A sand cushion is not only a leveling layer, it is an opportunity to cut off negative impact underground water onto the concrete floor. Sand has the property of capillary raising of water only to a height of 30 cm. If you pour it under any building structure precisely this layer, then water simply will not be able to reach it.

Attention! Sand should be poured in layers of 10-15 cm, compacting each one. If the level groundwater on the site does not exceed 2 m, then the sand layer can be laid with a thickness of 15-20 cm.

Subbase and waterproofing layer

The subbase serves as both a base for the next layers and a waterproofing barrier. Fill it with concrete grade M100 or M150 without reinforcement. There are no strict requirements for the evenness of its surface, but there should not be strong differences. It is recommended to fill the screed in one go without long breaks, so that cracks do not form at the joints later. It is better to load this layer after a couple of weeks, when the concrete has dried well.

The waterproofing layer is assembled from roll materials. This can be traditional roofing felt or roofing felt, today they are increasingly used polymer films and membranes. Optimal solution– lay a water vapor barrier.

Here are some installation requirements:

• rolled material is laid in strips with overlapping edges of 10-12 cm;
• the edges are secured with construction tape; if roofing felt is used, it is coated with hot bitumen or bitumen mastic(cold);
• waterproofing the floor on the ground is two layers laid in strips perpendicular to each other;
• the material is laid with an approach to the foundation strip to the height of the floor being poured, that is, the construction of the floor base itself is a floating structure that is not in contact with the foundation.

Thermal insulation layer

The next layer is insulation. The thickness is selected based on the selected thermal insulation product. If these are polystyrene foam boards, then 10 cm will be enough. If expanded clay, then at least 25-30 cm, perlite can be laid 15-20 cm thick.

Attention! If polystyrene foam boards are chosen as insulation, then they must be laid with offset sheets, preferably in half a panel, like brickwork. This makes it possible to evenly distribute the loads acting from the floor.

A few more points regarding waterproofing and floor insulation.

1. The expanded clay or perlite layers must be covered with a waterproofing film on top. Expanded polystyrene boards there is no need to close, because they practically do not change their properties when interacting with moisture.
2. If expanded clay is used as insulation, then there is an option to combine the base and thermal insulation material. That is, expanded clay is added to the concrete solution as a filler. And this mixture is poured over the pillow with a thickening of up to 20 cm.
3. If the groundwater level is below 2 m and the foundation structure itself has stood for 3 years, then the sub-base need not be filled.

Finishing screed

The last layer that forms the floor on the ground is concrete mortar grade M200, laid with a thickness of at least 10 cm. The floor screed is poured with mandatory reinforcement, where any metal grid(chain-link, plaster, expanded) with cells 5x5 cm. You can make a mesh structure yourself from wire with a diameter of 4-6 mm, by connecting rods with knitting wire or by welding.

Attention! It is necessary to ensure that the steel reinforcing frame is located inside the body concrete screed. Therefore, the mesh is placed on stands in the form of stones or metal profiles, cut into small pieces. Pieces of mesh are connected to each other with knitting wire.

Now you need to set the level of the poured layer. To do this, several threads are stretched between the opposite walls of the foundation with a step of 1-2 m between them. It is at their level that it will be necessary to pour the concrete solution to form the floor.

If the house is planned to have a heated floor heating system, then installation must be carried out before pouring the concrete. plastic pipes. The latter are attached to the reinforcing mesh or knitting wire, or with special metal or plastic clamps.

Video: Do-it-yourself floors on the ground when building a cottage

Alternative solutions

Floors on the ground in a private house on the ground floor can be constructed in a different way. There are many proposed technologies, among them there are quite unique ones that require minimum costs and not very much experience in construction operations. One of them - super floor from Knauf. This technology is otherwise called dry screed.

The beginning of the work is associated with three layers, as in conventional technology construction of floors on the ground. That is:

• pillow filling,
• pouring the base,
• laying waterproofing.

The rest of the technology is very different from the previous one:

Acoustic Group company, producing soundproofing materials, offers virtually the same floor design. Only instead of expanded clay, it contains mineral wool mats, which are factory glued to gypsum fiber board sheets. These panels are called ZIPS - soundproof panel systems. Basically, such slab material is intended to improve soundproofing properties the structure on which they are installed. But mineral wool is excellent insulation, therefore, ZIPS panels laid on the floor insulate the base, increase its noise insulation characteristics, and level it.

The only point that needs to be taken into account is the low load bearing capacity this gender. Therefore, according to GVL sheets It is recommended to additionally lay plywood with a thickness of at least 16 mm.

is a basic type of foundation, one of the most proven and deeply studied types of supporting structures.

The history of the construction of the belt goes back many centuries, so the statistics and design features have been worked out as closely and in detail as possible.

The strip foundation is harmoniously combined with units of other types of foundation or with structural elements of the building itself, allowing them to be implemented in various ways.

One such option is flooring on the ground, a simple solution that does not require long work and does not load the walls.

The technique is quite widespread and deserves a detailed description.

Floors on the ground are a technology for creating a subfloor resting directly on the underlying layers of soil. This technique is available in the absence of a basement or basement.. It is simple and economical, used mainly in auxiliary and outbuildings - garages, storage facilities, bathhouses, etc.

For residential buildings, this technology is used less frequently, as it requires high-quality, and ideally, installation of a “warm floor” system.

It should be borne in mind that the technique of installing floors on the ground is only suitable for traditional types of strip foundation and is not suitable for combined types supporting structures, such as pile-tape, etc.

Exist different types rough floors on the ground:

• Concrete screed supported on load-bearing walls.
• Layer supported concrete screed soil backfill and serves as a supporting platform for the walls.
• Boardwalk on joists.
• Dry screed with floating floor, etc.

Different design options require their own methods and composition of the floor pie on the ground. Flood It is impossible to apply directly onto the backfill layer; it is necessary to create appropriate preparatory layers that provide rigidity, resistance to loads and thermal insulation.

Wood flooring is easier to install, but also requires significant preparatory work.

Advantages and disadvantages

The advantages of flooring on the ground include:

• Simplicity and cost-effectiveness of creation.
• Ability to withstand high loads.
• Absence or low values ​​of loads on the walls.
• Durability, high maintainability.
• Ability to combine with any type of finishing coating.
• Possibility of installing a heated floor system.

There are also disadvantages And:

• The need for high-quality insulation.
• The device is not possible if the backfill layer is too thick (more than 0.6-1 m).
• Dependence on hydrogeological conditions in the region, impossibility of development in flooded areas or in regions with unstable groundwater levels.
• The need for a competent approach during construction.

All qualities of ground floors have been sufficiently well researched, which allows us to rely on technology and carry out work in strict accordance with its requirements.

What is the device (by layers)

For wood subfloors, creating a complex pie is not necessary. A mandatory layer of sand backfill is sufficient, on top of which geotextiles are laid and insulation is laid or poured. The composition of the cake for a concrete floor on the ground is more complex.

Typically the following layers are created:

• Sand backfill.
• A reinforcing mesh made of metal or fiberglass is laid.
• A rough layer of concrete screed 10 cm thick.
• Waterproofing layer.
• Insulation (expanded clay, polystyrene foam or, better, specialized penoplex).
• Additional layer of waterproofing.
• Clean concrete screed.

It is also recommended to reinforce the last layer to eliminate the possibility of cracks forming during drying. If necessary, water heated floor pipelines can be poured into it to obtain an effective and economical system heating the home.

What you need to know before construction

Before you start constructing a floor on the ground, you need to get enough full information about the composition of soil layers on the site, groundwater and the extent of seasonal fluctuations in their level.

This data will allow you to decide whether it is possible to create floors on the ground with a sufficient degree of safety for the building and its inhabitants. It is recommended to create a high-quality drainage system that can ensure the removal of soil moisture if its level increases.

Then you should decide on the thickness of the preparatory layers of backfill. This issue is of particular importance since they must be thoroughly compacted. The thicker the layer, the more difficult it is to achieve sufficient compaction.

At the same time, it is impossible to achieve the natural compaction density of the backfill layer in practice. The preparatory layer will certainly give some shrinkage, the amount of which will be directly proportional to its thickness.

It is recommended to pour a layer of footing concrete (rough screed) onto a geotextile fabric. This will preserve water in the array and ensure normal crystallization of the material. If you pour directly onto the preparatory layer, moisture from the concrete will be absorbed into it and disrupt the hardening process, which will result in a weakening of the screed.

When pouring all concrete layers, it is necessary to fully comply with the period necessary for the crystallization of the material and the development of technological strength. Otherwise, there is a risk of deformation or destruction of the underlying layers, the occurrence of defects in the geometry of the floor pie and loss of overall strength.

Before starting work, you must make sure that all communications passing under the floor level have been entered. After creating a floor pie on the ground, entering communications will be difficult and will require more complex methods for solving the issue.

Construction technologies on strip foundations

There are several methods for creating floors on the ground, involving the use of different techniques and materials. They all have their own advantages and disadvantages, and have sufficient efficiency and load-bearing capacity.

The choice of methodology is made based on a comparison of the features of the technology and the conditions that exist in reality. Besides, important factor are the capabilities and preferences of the home owner.

Let's consider the procedure for creating different technological options:

Concrete screed

Creating a concrete screed is the most labor-intensive and time-consuming process, requiring the use of “wet” solutions.

This feature must be taken into account in advance, since the specifics of the materials will require certain conditions:

• The air temperature is not lower than +5° (room temperature is optimal).
• No exposure to the scorching rays of the sun. If there is no roof, you can use a net or canopy for protection.
• Site prepared for work.

Work order:

• Creating a sand cushion layer. Up to 0.6 m of sand is poured (optimally - about 20 cm). The layer is carefully compacted to a state of maximum density. As a guide, you need to achieve density like on a country road.
• The next layer is backfilling with crushed stone. The thickness of the layer is the same as that of the previous sand layer - about 20 cm. Tamping allows not only to increase the strength of the crushed stone layer, but also makes it possible to further compact the sand layer.
• Laying geotextile fabric. The strips of material are overlapped by about 15 cm with an overlap on the walls of the foundation strip.
• Along the perimeter of the room on a tape damping tape is installed, providing mechanical decoupling of the floor and foundation.
• The reinforcing mesh is laid and the rough concrete screed is poured. It is maintained for the required time according to the technology until the material completely hardens.
• Applying a waterproofing layer. Used either double layer roofing felt coated with bitumen mastic, or various impregnations.
• Laying insulation. The best option- penoplex for foundation work, characterized by density and resistance to external influences.
• Laying steam-waterproofing film. The strips are laid with an overlap on the walls (over the damping tape) to a height of about 20 cm. The film is overlapped by 10-15 cm with sizing with construction tape.
• Laying reinforcing fiberglass mesh.
• Pouring finishing screed. Its thickness is usually 5-10 cm. If a heated floor system is used, then the installation and laying of pipelines, checking the strength of the connection under pressure and other previous operations are carried out first.

The total thickness of the floor pie along the ground is selected in such a way that the floor level is as convenient as possible for installation doorways and other building elements. It is best to carry out work in the warm season, when the conditions for hardening the concrete layers allow you to get the best results.

Dry screed

The technology for creating a dry screed makes it much easier and faster to get a high-quality result. The initial stages of work are the same as in the previous version - creating layers of sand backfill and rough concrete screed.

After this the following steps are performed:

• Laying waterproofing film using conventional technology - creating a sealed sheet of film strips folded in rows with a 10 cm overlap with the joints taped with adhesive tape. The edges of the canvas are placed on the wall to the approximate height of the dry screed.
• Installation of beacons. The recommended option is plaster profiles. They will serve as guides for creating a horizontal and level plane.
• Filling a layer of expanded clay. The material is aligned along the beacons, forming a horizontal plane.
• Subfloor slabs - plasterboard, plywood, etc. - are laid on top of the expanded clay. The most recommended option is tongue-and-groove plasterboard, which has a special profile along the side edges for connection.
• After this, the final finishing coating is laid.

Wood flooring

This option is considered the most budget-friendly. The simplest and most reliable design rests on pillars of bricks stacked in a well. The columns are placed in such a way that a support system is formed for installing the logs.

The columns are filled with expanded clay or, alternatively, left air gap to ensure dry wood, which requires the creation of ventilation holes.

The joist system is carefully leveled horizontally and forms an even supporting plane. Then a wooden subfloor is laid. A layer of waterproofing film is installed on top, a standard substrate is laid and a finishing coating is laid - linoleum, laminate or other material to the owner’s taste.

Which construction technology is best to choose?

The choice of technology is a matter of preference and capabilities of the home owner. Concrete screed allows you to get a durable and strong floor, but its maintainability will be extremely low. Failure of, for example, a heated floor system will create serious problem with a very complex and costly solution.

Dry screed is much simpler and allows for repairs without special costs and problems, but this option is only suitable for people who are not afraid of repair work.

NOTE!

A wooden floor is a traditional solution, but the specifics of wood as a material have too many undesirable aspects, so this option is increasingly being abandoned in favor of other methods.

Conclusion

Creating a floor on the ground is an option suitable for buildings that do not have a basement or basement.

For housing, this method is used less frequently, since most users consider it unreliable and dangerous in relation to ground moisture.

When deciding to use this technique, you need to weigh all the pros and cons, think through the procedure and perform all the preliminary work - entering communications, creating, etc.

This will allow you to obtain a result that is optimal in quality and performance capabilities.

In contact with

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 high level groundwater, then 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. She gets comfortable without polyethylene 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:

1. From the groundwater level;
2. It depends on whether these floors will be with heat transfer fluids (warm) or not;
3. 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 can be in 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

These important points I would like to analyze 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 from brick (into brick), from septal block(100 mm), and the walls are 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 for laying 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, the waterproofing must be laid on a level 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 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

As a rule, in order to install a floor on the ground on a strip foundation, you should know many nuances that will be useful in constructing a concrete structure. The type of building material will directly depend on the wishes of the owner and the method of application.

Installation of flooring material can be carried out in the same way on concrete base screeds, wood or monolithic slab. If a concrete slab is made, it must be attached to the foundation using reinforcement, or it will be floating. In the case of installing a floor on the ground itself, a primary gravel cushion is made.

What the developer needs to remember

Properly insulate the base and floor along the ground, otherwise most of heat will go into the soil

The design has enhanced operational capability. But for this you will need to choose the right material.

To make it easier to understand the structure of the pie from the inside, you will need to study the factors that affect the concrete slab:

In connection with the above factors, it is necessary to focus Special attention laying the cake in the case of a strip base. Thanks to this, the reliability of the entire structure as a whole will significantly increase.

It is important to remember when building the foundation that engineering structures after some time they may fail, and it will not be possible to replace them. To solve this problem, you can install a backup engineering type system.

Main installation options

Nowadays you can install flooring on the ground using two technology options to choose from. In this case, all these actions are performed different ways execution. The first method is considered the most financially effective and not too labor-intensive.

Layout of a floor on the ground

An option for this design is installing the floor using wooden beams. Can be replaced if desired wood material steel beams. However, such a choice cannot help but hit your finances.

Let's move on to consider the negative aspects of this gender:

The second method is considered the most expensive, but expensive does not always mean bad. This method is a poured floor, while it is insulated and a layer of waterproofing is laid. This method is considered the most reliable and effective.

Preparatory stage

Before installing the insulated screed, make markings

This stage of work involves preparing the soil for upcoming loads and installing an insulated screed. To do the work yourself, there is the following procedure:

1. Performing markings. Measure the floor of the basement; if it is missing, then measure the first floor. These marks will serve as the starting point of the overlap, and this surface will also be the place on which you walk. The threshold of the room, be it a basement or the entrance to a private building, will be the starting point. Thickness is subtracted from the reference point concrete slab. On next stage The work is carried out by making several marks on the foundation. Thus, the points of the lower and upper parts of the floor become known. You can perform all actions using a level; with its help, accuracy will increase and the work process will significantly speed up.
2. Further preparatory actions. For a concrete slab, or rather a floor, the base is basement there will be dense layers of soil. You can use a vibrator to compact the soil. However, for use this mechanism availability will be required special tool. Also, compaction of the soil structure can be done using a bulk mass, which is a log with a diameter of at least 30 cm. To perform this important task, a wide platform is attached to the tree trunk. Under its influence and the total weight of the wood, the soil is compacted.
3. Preliminary actions in relation to monolithic slab strip base is an additional bedding throughout the basement area. To make it you will need the following Construction Materials as: sand or crushed stone of medium fraction. When purchasing material for powdering, you should remember that sand must be selected at least average size. The size of the bedding layer should not exceed 50 cm. Sandy view pillows play a role drainage system, which evenly transfers mass from the building to the ground. In some situations, in order to make the layers denser, they are watered with a small volume of water, after which they are sprinkled and compacted again.
4. An important component of a strip-type foundation is the installation quality protection from humidity. Most often, ordinary film is used for this, which is made of polyethylene or membrane types of materials with high density. Pouring the concrete screed can only be done after the waterproofing has been laid out around the entire perimeter of the room. It is important to remember that all connections waterproofing material must be connected exclusively with an overlap. The film must be made larger than the area of ​​the room, this is necessary in order to bend the edges. For details of preparation and laying on the ground, see this video:

It is important to remember during the period of pouring the screed that the floor structure can be made warm. This action can be performed using a heated floor design. It runs on electricity, and consumes a small amount of energy, but heats the entire area well.

The final stage in arranging the floor on the ground

In order to make a concrete structure for a reliable floor, the pouring process must be carried out in several stages. If the concrete consistency will be made with your own hands, then the following material will be useful:

• cement grade 300 or 400;
• fine sand;
• water;
• medium small crushed stone.

All of the above elements should be thoroughly mixed in an electric concrete mixer, adhering to certain proportions. If this is not available construction tools, can be made wooden box. You can mix concrete consistency in it. Answers to basic questions about the device of this type watch the floors in this video:

Fill the concrete mixture along the beacons

Level beacons are installed in the room. The floor will be poured along them. A well-mixed solution is poured from the extreme corners of the room, while tamping is performed. This is necessary so that there is no porosity, that is, air formations, in the structure of the concrete consistency.

Levels out concrete mixture indoors using a special long aluminum rule. After pouring concrete, the room should be left for 30 days. This time will be enough for the structure to fully harden.

After this period, a specialized mixture is poured over the structure, which is necessary for quality leveling errors.