Schemes for installing a floor on the ground in a house, basement, garage or bathhouse

In houses without basements, the floor of the first floor can be made according to two schemes:

• supported on the ground - with a screed on the ground or on joists;
• supported on walls - like a ceiling over a ventilated underground.

Which of the two options will be better and easier?

In houses without a basement, floors on the ground are a popular solution for all rooms on the first floor. Floors on the ground are cheap, simple and easy to make; it is also beneficial to install them in the basement, garage, bathhouse and others. utility rooms. Simple design, the use of modern materials, the placement of a heating circuit in the floor (warm floor), such floors are made comfortable and attractively priced.

In winter, the backfill under the floor always has a positive temperature. For this reason, the soil at the base of the foundation freezes less - the risk of frost heaving of the soil is reduced. In addition, the thickness of the thermal insulation of a floor on the ground may be less than that of a floor above a ventilated underground.

It is better to abandon the floor on the ground if backfilling with soil is required to a height that is too high, more than 0.6-1 m. The costs of backfilling and soil compaction in this case may be too high.

A ground floor is not suitable for buildings on a pile or columnar foundation with a grillage located above the ground surface.

Three basic diagrams for installing floors on the ground

In the first version concrete monolithic reinforced floor slab rests on load-bearing walls, Fig.1.

After the concrete hardens, the entire load is transferred to the walls. In this option, a monolithic reinforced concrete floor slab plays the role of a floor slab and must be designed for the standard load of the floors, have the appropriate strength and reinforcement.

The soil is actually used here only as temporary formwork when installing iron concrete slab ceilings This type of floor is often called a “suspended floor on the ground”.

A suspended floor on the ground has to be made if there is a high risk of shrinkage of the soil under the floor. For example, when building a house on peat bogs or when the height of the bulk soil is more than 600 mm. The thicker the backfill layer, the higher the risk of significant subsidence of the fill soil over time.

Second option - this is a floor on a foundation - a slab, when reinforced concrete monolithic slab, poured onto the ground over the entire area of ​​the building, serves as a support for the walls and a base for the floor, Fig.2.

Third option involves the installation of a monolithic concrete slab or the laying of wooden logs in the spaces between load-bearing walls supported on bulk soil.

Here the slab or floor joists are not connected to the walls. The load of the floor is completely transferred to the bulk soil, Fig.3.

It is the latter option that is correctly called a floor on the ground, which is what our story will be about.

Ground floors must provide:

• thermal insulation of premises in order to save energy;
• comfortable hygienic conditions for people;
• protection against penetration of ground moisture and gases - radioactive radon - into premises;
• prevent the accumulation of water vapor condensation inside the floor structure;
• reduce the transmission of impact noise to adjacent rooms along the building structures.

Backfilling the soil cushion for the floor on the ground

The surface of the future floor is raised to the required height by installing a cushion of non-heaving soil.

Before starting work on backfilling, be sure to remove the top soil layer with vegetation. If this is not done, the floor will begin to settle over time.

Any soil that can be easily compacted can be used as a material for constructing a cushion: sand, fine crushed stone, sand-gravel mixture, and at a low level groundwater– sandy loams and loams. It is beneficial to use the soil remaining on the site from the well and (except for peat and black soil).

The cushion soil is carefully compacted layer by layer (no thicker than 15 cm.) by compacting and pouring water onto the soil. The degree of soil compaction will be higher if mechanical compaction is used.

Do not place large crushed stones, broken bricks, or pieces of concrete into the cushion. There will still be voids between large fragments.

The thickness of the bulk soil cushion is recommended to be in the range of 300-600 mm. It is still not possible to compact the fill soil to the state of natural soil. Therefore, the soil will settle over time. A thick layer of fill soil can cause the floor to settle too much and unevenly.

To protect against ground gases - radioactive radon, it is recommended to make a layer of compacted crushed stone or expanded clay in the cushion. This underlying captage layer is made 20 cm thick. The content of particles smaller than 4 mm this layer should contain no more than 10% by weight. The filtration layer must be ventilated.

The top layer of expanded clay, in addition to protecting against gases, will serve as additional thermal insulation for the floor. For example, a layer of expanded clay 18 cm. corresponds to 50 in terms of heat-saving ability mm. polystyrene foam To protect against crushing of insulation boards and waterproofing films, which in some floor designs are laid directly on the backfill, a leveling layer of sand is poured on top of the compacted layer of crushed stone or expanded clay, the thickness of which is twice the size of the backfill fraction.

Before filling the soil cushion, it is necessary to lay water supply and sewerage pipes at the entrance to the house, as well as pipes for the ground ventilation heat exchanger. Or lay cases for installing pipes in them in the future.

Construction of floors on the ground

In private housing construction, the floor on the ground is arranged according to one of three options:

• ground floor with concrete screed;
• ground floor with dry screed;
• ground floor on wooden joists.

A concrete floor on the ground is noticeably more expensive to construct, but is more reliable and durable than other structures.

Concrete floor on the ground

Floors on the ground are a multi-layer structure, Fig.4. Let's go through these layers from bottom to top:

1. Placed on a ground cushion material that prevents filtration into the groundmoisture contained in freshly laid concrete (for example, polyethylene film with a thickness of at least 0.15 mm.). The film is applied to the walls.
2. Along the perimeter of the walls of the room, to the total height of all layers of the floor, fix separating edge layer from strips 20 – 30 thick mm, cut from insulation boards.
3. Then they arrange a monolithic concrete floor preparation thickness 50-80 mm. from lean concrete class B7.5-B10 to crushed stone fraction 5-20 mm. This is a technological layer intended for gluing waterproofing. The radius of concrete joining the walls is 50-80 mm. Concrete preparation can be reinforced with steel or fiberglass mesh. The mesh is laid in the lower part of the slab with a protective layer of concrete of at least 30 mm. For reinforcing concrete foundations it can alsouse steel fiber length 50-80 mm and diameter 0.3-1mm. During hardening, the concrete is covered with film or watered. Read:
4. For hardened concrete floor preparation weld-on waterproofing is glued. Either two layers of rolled waterproofing or roofing material on a bitumen base with each layer placed on the wall. The rolls are rolled out and joined with an overlap of 10 cm. Waterproofing is a barrier to moisture and also serves as protection against the penetration of ground gases into the house. The floor waterproofing layer must be combined with a similar wall waterproofing layer. Butt joints of film or roll materials must be sealed.
5. On a layer of hydro-gas insulation lay thermal insulation slabs. Extruded polystyrene foam will probably be the best option for insulating floors on the ground. Foam plastic with a minimum density of PSB35 (residential premises) and PSB50 for heavy loads (garage) is also used. Polystyrene foam breaks down over time upon contact with bitumen and alkali (these are all cement-sand mortars). Therefore, before laying foam plastic on a polymer-bitumen coating, one layer of polyethylene film should be laid with an overlap of sheets of 100-150 mm. The thickness of the insulation layer is determined by thermal engineering calculations.
6. On the thermal insulation layer lay the underlying layer(for example, polyethylene film with a thickness of at least 0.15 mm.), which creates a barrier to moisture contained in freshly laid concrete floor screed.
7. Then lay a monolithic reinforced screed with a “warm floor” system (or without a system). When heating floors, it is necessary to provide in the screed expansion joints. The monolithic screed must be at least 60 thick mm. executed from concrete class not lower than B12.5 or from mortarbased on cement or gypsum binder with a compressive strength of at least 15 MPa(M150 kgf/cm 2). The screed is reinforced with welded steel mesh. The mesh is placed at the bottom of the layer. Read: . For more thorough surface leveling concrete screed, especially if the finished floor is made of laminate or linoleum, a self-leveling solution of factory-made dry mixes with a thickness of at least 3 is applied on top of the concrete layer cm.
8. On the screed installing finished floor.

This is a classic ground floor. On its basis it is possible various options execution - both in design and in the materials used, both with and without insulation.

Option - concrete floor on the ground without concrete preparation

Using modern building materials, concrete floors on the ground are often made without a layer of concrete preparation. A layer of concrete preparation is needed as a base for the sticker roll waterproofing on a paper or fabric base impregnated with a polymer-bitumen composition.

In floors without concrete preparation As waterproofing, a more durable polymer membrane specially designed for this purpose is used, a profiled film, which is laid directly on the ground cushion.

The profiled membrane is a sheet of polyethylene high density(PVP) with protrusions molded on the surface (usually spherical or in the shape of a truncated cone) with a height of 7 to 20 mm. The material is produced with a density from 400 to 1000 g/m 2 and is supplied in rolls with widths ranging from 0.5 to 3.0 m, length 20 m.

Due to the textured surface, the profiled membrane is securely fixed in sandy base without deforming or moving during installation.

Fixed in a sand base, the profiled membrane provides hard surface, suitable for laying thermal insulation and concrete.

The surface of the membranes can withstand the movement of workers and machines for transporting concrete mixtures and solutions (excluding crawler-mounted machines) without breaking.

The service life of the profiled membrane is more than 60 years.

The profiled membrane is laid on a well-compacted sand bed with the spikes facing down. The membrane spikes will be fixed in the pillow.

The seams between the overlapping rolls are carefully sealed with mastic.

The studded surface of the membrane gives it the necessary rigidity, which allows you to lay insulation boards directly on it and concrete the floor screed.

If slabs made of extruded polystyrene foam with profiled joints are used to construct a thermal insulation layer, then such slabs can be laid directly on the ground backfill.

Backfill of crushed stone or gravel with a thickness of at least 10 cm neutralizes the capillary rise of moisture from the soil.

In this embodiment, the polymer waterproofing film is laid on top of the insulation layer.

If upper layer If the ground cushion is filled with expanded clay, then you can dispense with the insulation layer under the screed.

The thermal insulation properties of expanded clay depend on its bulk density. From expanded clay with bulk density 250–300 kg/m 3 it is enough to make a thermal insulation layer with a thickness of 25 cm. Expanded clay with bulk density 400–500 kg/m 3 to achieve the same thermal insulation ability, you will have to lay it in a layer 45 thick cm. Expanded clay is poured in layers 15 thick cm and compacted using a manual or mechanical tamper. The easiest to compact is multi-fraction expanded clay, which contains granules of different sizes.

Expanded clay is quite easily saturated with moisture from the underlying soil. Wet expanded clay has reduced thermal insulation properties. For this reason, it is recommended to install a moisture barrier between the base soil and the expanded clay layer. A thick waterproofing film can serve as such a barrier.

Large-porous expanded clay concrete without sand, encapsulated. Each expanded clay granule is enclosed in a cement waterproof capsule.

The base for the floor, made of large-porous sand-free expanded clay concrete, will be durable, warm and with low water absorption.

Floor on the ground with dry prefabricated screed

In ground floors, instead of a concrete screed as the top load-bearing layer, in some cases it is advantageous to make a dry prefabricated screed from gypsum fiber sheets, from sheets of waterproof plywood, as well as from prefabricated floor elements from different manufacturers.

For residential premises on the first floor of the house more than simple and cheap option There will be a floor on the ground with a dry prefabricated floor screed, Fig. 5.

A floor with a prefabricated screed is afraid of flooding. Therefore, it should not be done in the basement, as well as in wet rooms - bathroom, boiler room.

The ground floor with a prefabricated screed consists of the following elements (positions in Fig. 5):

1 — Flooring- parquet, laminate or linoleum.

2 - Glue for joints of parquet and laminate.

3 - Standard underlay for flooring.

4 - Prefabricated screed from ready-made elements or gypsum fiber sheets, plywood, particle boards, OSB.

5 - Glue for assembling the screed.

6 - Leveling backfill - quartz or expanded clay sand.

7 - Communications pipe (water supply, heating, electrical wiring, etc.).

8 - Insulation of the pipe with porous fiber mats or polyethylene foam sleeves.

9 - Protective metal casing.

10 — Expanding dowel.

11 - Waterproofing - polyethylene film.

12 - Reinforced concrete base made of class B15 concrete.

13 - Foundation soil.

The connection between the floor and the outer wall is shown in Fig. 6.

The positions in Fig. 6 are as follows:
1-2. Varnished parquet, parquet, or laminate or linoleum.
3-4. Parquet adhesive and primer, or standard underlay.
5. Prefabricated screed from ready-made elements or gypsum fiber sheets, plywood, particle boards, OSB.
6. Water-dispersed adhesive for screed assembly.
7. Moisture insulation - polyethylene film.
8. Quartz sand.
9. Concrete base - reinforced concrete screed of class B15.
10. Separating gasket made of waterproofing roll material.
11. Thermal insulation made of polystyrene foam PSB 35 or extruded polystyrene foam, thickness as calculated.
12. Foundation soil.
13. Plinth.
14. Self-tapping screw.
15. External wall.

As mentioned above, the soil cushion at the base of the floor always has a positive temperature and in itself has certain heat-insulating properties. In many cases, it is enough to additionally lay insulation in a strip along the external walls (pos. 11 in Fig. 6.) in order to obtain the required thermal insulation parameters for a floor without underfloor heating (without heated floors).

Thickness of floor insulation on the ground

Fig.7. Be sure to lay insulation tape in the floor, along the perimeter of the external walls, with a width of at least 0.8 m. From the outside, the foundation (basement) is insulated to a depth of 1 m.

The temperature of the soil under the floor, in the area adjacent to the plinth along the perimeter of the external walls, depends quite strongly on the temperature of the outside air. A cold bridge forms in this zone. Heat leaves the house through the floor, soil and basement.

The ground temperature closer to the center of the house is always positive and depends little on the temperature outside. The soil is heated by the heat of the Earth.

Building regulations require that the area through which heat escapes be insulated. For this, It is recommended to install thermal protection at two levels (Fig. 7):

1. Insulate the basement and foundation of the house from the outside to a depth of at least 1.0 m.
2. Lay a layer of horizontal thermal insulation into the floor structure around the perimeter of the external walls. The width of the insulation tape along the external walls is not less than 0.8 m.(pos. 11 in Fig. 6).

The thickness of the thermal insulation is calculated from the condition that the overall resistance to heat transfer in the area floor - soil - base must be no less than the same parameter for outer wall.

Simply put, the total thickness of the insulation of the base plus the floor should be no less than the thickness of the insulation of the outer wall. For climate zone in the Moscow region, the total thickness of foam insulation is at least 150 mm. For example, vertical thermal insulation on a plinth 100 mm., plus 50 mm. horizontal tape in the floor along the perimeter of the external walls.

When choosing the size of the thermal insulation layer, it is also taken into account that insulating the foundation helps reduce the depth of freezing of the soil under its base.

This minimum requirements to insulate the floor on the ground. It is clear that what larger sizes thermal insulation layer, the higher the energy saving effect.

Install thermal insulation under the entire floor surface for the purpose of energy saving, it is only necessary in the case of installing heated floors in the premises or building an energy-passive house.

In addition, a continuous layer of thermal insulation in the floor of the room can be useful and necessary to improve the parameter heat absorption of the floor covering surface. Thermal absorption of the floor surface is the property of the floor surface to absorb heat in contact with any objects (for example, the feet). This is especially important if the finished floor is made of ceramic or stone tiles, or other material with high thermal conductivity. Such a floor with insulation will feel warmer.

The heat absorption index of the floor surface for residential buildings should not be higher than 12 W/(m 2 °C). A calculator for calculating this indicator can be found

Wooden floor on the ground on joists on a concrete screed

Base slab made of concrete class B 12.5, thickness 80 mm. over a layer of crushed stone compacted into the ground to a depth of at least 40 mm.

Wooden blocks - logs with a minimum cross-section, width 80 mm. and height 40 mm., It is recommended to lay on a layer of waterproofing in increments of 400-500 mm. For vertical alignment, they are placed on plastic pads in the form of two triangular wedges. By moving or spreading the pads, the height of the lags is adjusted. The span between adjacent support points of the log is no more than 900 mm. A gap of 20-30 mm wide should be left between the joists and the walls. mm.

The logs lie freely without attachment to the base. During the installation of the subfloor, they can be fastened together with temporary connections.

For the installation of a subfloor it is usually used wood boards— OSB, chipboard, DSP. The thickness of the slabs is at least 24 mm. All slab joints must be supported by joists. Wooden lintels are installed under the joints of the slabs between adjacent logs.

The subfloor can be made from tongue-and-groove floorboards. This kind of floor quality board Can be used without floor covering. The permissible moisture content of wood flooring materials is 12-18%.

If necessary, insulation can be laid in the space between the joists. Mineral wool slabs must be covered with a vapor-permeable film on top, which prevents microparticles of insulation from penetrating into the room.

Rolled waterproofing made of bitumen or bitumen-polymer materials glued in two layers onto the concrete underlying layer using the melting method (for fused rolled materials) or by sticking on bitumen-polymer mastics. When installing adhesive waterproofing, it is necessary to ensure a longitudinal and transverse overlap of the panels of at least 85 mm.

To ventilate the underground space of floors on the ground along the joists, the rooms must have slots in the baseboards. Holes with an area of ​​20-30 are left in at least two opposite corners of the room. cm 2 .

Wooden floor on the ground on joists on posts

There is another structural floor scheme - this wooden floor on the ground on joists, laid on posts, Fig.5.

Positions in Fig.5:
1-4 - Elements of the finished floor.
5 —
6-7 - Glue and screws for assembling the screed.
8 - Wooden joist.
9 — Wooden leveling gasket.
10 - Waterproofing.
11 - Brick or concrete column.
12 - Foundation soil.

Arranging the floor on joists along columns allows you to reduce the height of the ground cushion or completely abandon its construction.

Floors, soils and foundations

Ground floors are not connected to the foundation and rest directly on the ground under the house. If it is heaving, then the floor can “go on a spree” under the influence of forces in winter and spring.

To prevent this from happening, the heaving soil under the house must be made not to heave. The easiest way to do this is the underground part

Design of pile foundations on bored (including TISE) and screw piles involves the installation of a cold base. Insulating the soil under a house with such foundations is a rather problematic and expensive task. Floors on the ground in a house on a pile foundation can only be recommended for non-heaving or slightly heaving soils on the site.

When building a house on heaving soils, it is necessary to have an underground part of the foundation to a depth of 0.5 - 1 m.

In a house with external multilayer walls with insulation on the outside, a cold bridge is formed through the base and load-bearing part of the wall, bypassing the insulation of the wall and floor.

The most rational decision For an individual developer, it is concreting the floor on the ground in the form of a floating screed. When using other options (beam-based flooring, PC slab), harmful radon can accumulate inside the underground, and there is often a lack of normal ventilation. Excess moisture leads to corrosion of concrete and biological damage to wood.

Installing a floor on the ground in a private cottage is often confused with pouring monolithic ceiling resting on a plinth or foundation elements, when the bottom permanent formwork served as backfilled but not compacted soil inside the MZLF tape. This different technologies, the differences of which will be discussed below.

The developer should understand that for specific conditions, the design of a concrete floor on the ground (PG) should be chosen correctly, based on the conditions:

• with floors on the ground, it is necessary to create a single base for laying the floor covering;
• the structure is a floating screed that does not come into contact with the walls of the building and does not go under them;

Confusion in the names of technologies occurs for the following reasons:

• the project includes a foundation whose width is greater than the thickness of the walls;
• the enclosing structures are shifted outward ( inner surface plinth, grillage or MZLF tape does not coincide with the plane of the internal walls).

In this case, the developer tries to avoid the resulting step, raises the floor level, pours the screed not only onto the ground, but also rests it on the protruding parts of the foundation. The MZLF backfill or grillage in this case serves as formwork, but is not compacted properly.

During operation, the soil under the slab or the foundation under the building itself may sag or rise due to heaving forces. Where the slab rests on the plinth, serious loads arise that are not taken into account in the calculations. The screed breaks and the flooring becomes unusable.

It is important to understand that when you make a floating screed on the ground with your own hands, it rests on tightly compacted soil and cannot sag or swell. Therefore, mesh reinforcement in one layer in the lower third of the structure is sufficient. Slabs supported on foundation/plinth elements are always reinforced in two levels. By filling the foundation/basement in this option, other problems are solved:

• the developer gets rid of the underground, inside of which it is necessary to provide natural ventilation, A low base does not allow you to make vents in it, since they will be covered with snow in winter;
• the accumulation of harmful radon gas inside the underground, freezing of the soil under the cottage is eliminated and heat loss in the floors is reduced;
• formwork costs are reduced, since the lower deck is earth, which does not need to be compacted with a vibrating plate.

There is an option for installing a floor on the ground with “support” on the foundation, but the support occurs through the foundation layer, and the soil must be well compacted, i.e. in fact, the floor does not rest on the foundation, because Due to local compression of the insulation at the point of support on the base, all movements are leveled out. That is why you should not use high-density insulation for such a design.

The floor is on the ground with “rest” on the plinth.

The concrete floor on the ground has the following design:

• backfilling - the topsoil layer must be completely removed; soil taken from the MZLF trenches can be used, but only with a minimum clay content, compacted layer by layer with a vibrating plate;
• underlying layer - necessary for additional leveling, recommended thickness 40 cm, created from sand (on dry soils) or crushed stone with geotextiles (at high ground water level), compacted with a vibrating plate (every 10 - 15 cm);
• footing - a screed is necessary to protect the waterproofing material from punctures by the sharp edges of crushed stone; it can be filled with thin (B7.5) concrete mortar;
• waterproofing - EPDM films, two-layer polyethylene or fused bitumen roll material, which prevents concrete from getting wet and corrosion of the reinforcement inside it;
• insulation - just make a 5-10 cm layer of high-density polystyrene foam (XPS or EPS);
• reinforced concrete – mesh reinforced in the lower level there is a concrete screed B15 and higher (corresponding to M200).
• damper layer - along the perimeter the screed is separated from the walls, base or foundation by a special tape or insulation installed on the edge;
• expansion joint - necessary in openings between rooms, arranged by laying special elements (corners) when pouring the structure.

Layout of expansion joints.

This is the only thing correct design PG for a private cottage. However, individual developers often try to save money on installing a floor on the ground, so the following options exist:

• V backfill Expanded clay is used instead of soil - the material is very difficult to compact, but it is light and has thermal insulation properties(but nevertheless it cannot replace a layer of insulation), instead of a concrete base, the surface is covered with cement laitance, which binds the top layer and makes it suitable for laying waterproofing;
• exception of the footing - a layer of sand with a thickness equal to two sizes of the maximum crushed stone fraction is laid on top of the crushed stone, after which the non-metallic material is compacted so that no traces of workers’ shoes remain on it, waterproofing is laid on it, but is not glued, but is sealed in places where they overlap each other .

Private residential projects often contain partitions and free-standing structures that are heavy (from 400 kg) and exert concentrated point loads.

Important! A floor on the ground is not a load-bearing structure, so for stoves/fireplaces, internal stairs and heavy partitions it is necessary independent foundation, which can be built into the floor along the ground or take the form of piles, slabs, pillars.

Foundation options for stairs.

Manufacturing technology

Before making a PG with your own hands according to the above scheme, it is not enough to know its design. The nuances of construction at each stage, given below, should be taken into account. The main misconception is that PG is only suitable for strip foundations of a private house.

In fact, a floating screed can be poured into houses with a low grillage on screw and bored piles, classic and TISE pillars. In this case, the thickness of the structure and its structure remain the same, and the PG is adjacent to the walls on a grillage.

Backfill MZLF for floors on the ground.

Preparation

The floor structure on the ground must have a base with normal bearing capacity. The PG is made inside a grillage or MZLF, the beams of which rise above the ground, creating the base part of the foundation. Therefore, it would be correct to fill the internal cavities with soil taken out of the trenches strip foundation, leaving 0.4 m for non-metallic material.

If there is a topsoil containing a large amount of organic matter, it must be removed. Even if you compact the chernozem with a vibrating plate, after 3–12 months the organic matter in it will rot and the soil will certainly sag, which is extremely dangerous for concrete, even if reinforced, but not connected to the foundation.

Important! At this stage, the elements of the grillage, plinth or foundation should be treated with waterproofing materials (plaster, built-up or coating), if this has not been done previously.

Communications

Unlike a floating foundation slab, the input nodes for engineering systems are installed with your own hands before backfilling the underlying layer. The exact location of the walls is already known, since the grillage or MZLF has already been made. Therefore, it is impossible to make a mistake with the passage of risers in close proximity to the enclosing structures.

Even with a minimum screed thickness, the maintainability of communications inside the steam generator is practically zero. Therefore, the following technology is used:

• the water supply system is buried by 1 - 1.5 m, since the soil under the cottage cannot freeze (only for all-season housing), sewerage by 0.7 - 1 m, since the wastewater leaves the house warm;
• pipes run in sleeves or corrugated pipe larger diameter, so that if they fail, you can pull out part of the circuit from outside or inside the house and replace them with new ones;
• If necessary, you can run a power cable into the cottage at a depth of 0.5 m, laying red warning tape on top of it.

Communications inside the underlying layer.

You can maximize the quality and service life of engineering systems in a private house by installing an underlying layer:

• trenches are dug for water and sewer pipes;
• geotextiles are laid, the edges of which are attached to the sides of the excavation;
• a 5–10 cm layer of sand/crushed stone is poured;
• communications are laid out;
• covered with the same non-metallic material on top and sides;
• covered with the remains of geotextiles and covered with soil.

This will compensate for possible heaving forces and maintain the integrity of engineering systems.

Substrate

Filling the top layer with nonmetallic material is a technology that eliminates heaving forces. Crushed stone and sand have drainage properties, serve as a damper layer of the floor on the ground, are normally compacted by a vibrating plate and do not sag over time.

Sand preparation of the floor on the ground.

However, these materials absorb cement laitance from concrete and do not allow the joints of rolled waterproofing to be properly sealed. Therefore, on top of the underlying layer you need to pour a footing - 3 - 5 cm of screed from a mixture of grade B 7.5.

Waterproofing and insulation

After the footing has gained strength, rolls are fused onto its surface. bituminous materials with overlapping strips of 10 - 15 cm. The edges are launched onto the vertical surfaces of the grillage or strip foundation of a private cottage to the height of the floor along the ground.

Waterproofing and insulation of PG.

The optimal insulation option for the SG design under consideration is high-density extruded polystyrene foam of the XPS or EPS grades. It does not sag, retains its properties in water and has high vapor barrier properties.

Important! With the specified “pie” of the floor along the ground, the insulation remains under the concrete, the structure has high thermal inertia (it accumulates heat, but also increases the energy consumption in the heating boiler during initial heating).

Reinforcement and heated floor

Due to the fact that a concrete floor on the ground absorbs exclusively compressive loads, its lower layer must be reinforced to compensate for destruction from tensile forces. For this purpose, a wire mesh made of rods with a diameter of 4 mm with a cell of 10 x 10 cm is used, in accordance with SP 63.13330 (reinforced concrete structures).

Reinforcement of the floor on the ground.

According to the regulations of the above joint ventures, concreting of the steam generator must be carried out in compliance with the following conditions:

• lower protective layer of concrete 1.5 cm minimum;
• to ensure this, the mesh is laid on polymer or concrete bosses; the use of metals and crushed stone is prohibited;
• when extending the mesh, the overlap is 10 cm minimum (one cell).

If the project includes a heated floor (HF), its contours are laid on top of the reinforcing mesh, and the thickness of the floating screed automatically increases.

Concreting

• it is forbidden to cut the mesh;
• to pass the rods through the partition, you will have to cut the required number of grooves in the shield;
• install the formwork in place and foam the remaining cracks;
• nail a beam on one side of the partition to create a ledge in the concrete for connection with the next piece of screed.

Before pouring, a damper layer must be installed. To do this, along the perimeter of the PG, pieces of thin (1 cm) polystyrene foam are installed vertically, close to the foundation of a private cottage, protruding beyond the design floor level, or the perimeter is covered with damper tape, which performs the same function.

Damping layer for floating screed.

The mixture is placed from the corner farthest to the concrete mixer with a ledge. Then it is compacted with a vibrating screed and leveled using the beacons.

Nuances of technology

The strength of floors on the ground is affected by the grade of concrete, the sequence of operations and the materials used. However, there are common features when concreting junction points, platforms for supporting heavy structures and light partitions.

Junction nodes

To reduce heat loss in floors as much as possible with your own hands, the insulation on the outer edge of the base and foundation must be connected to thermal insulation material inside or on walls outer surface(ventilated facade or wet facade) without cold bridges.

Insulation of the wall and base to eliminate cold bridges.

Partitions and walls

Since floors on the ground are not a load-bearing structure, under load-bearing walls and heavy partitions you need to pour a separate foundation. Another option is stiffening ribs along these walls, directed towards the ground, similar to the Swedish USHP slab.

A rather complicated case is gypsum plasterboard partitions on the floor on the ground:

• on the one hand, the PG needs to be separated from the partition by a damper layer, that is, a screed must be made after installing the partition;
• on the other hand, plasterboard systems should be erected after wet processes are completed, otherwise the material will absorb moisture and lose rigidity and strength.

Therefore, a combined technique is used:

• a profile frame is mounted on the foundation;
• a narrow strip of drywall is attached, the width of which is equal to the height of the floating screed;
• damper tape is glued to it or polystyrene foam is installed;
• The screed is poured, after which the partitions dry, they are completely sheathed with plasterboard.

Installation of the frame for the partition.

This avoids the drywall getting wet when the concrete dries and preserves the properties of structural materials.

Ladders and power equipment

Internal building structures can be significant and place concentrated loads on small areas. Therefore, for fireplaces, interfloor stairs, pumping equipment, furnaces and boilers, it is necessary to make a separate foundation or increase the thickness of the floor slab along the ground.

Thus, an individual developer can use ground floor technology for a low grillage and MZLF tape in order to reduce the construction budget and operating costs, and increase living comfort.

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Flooring is one of the most important components of any room. Today, concrete foundations are especially popular. They are durable and practical, which allows them to be used in various types of homes. A concrete floor on the ground in a private house is perfect for solving many problems. The design can withstand loads perfectly and also lasts for a long time without losing its original qualities.

Peculiarities

Concrete floors in private homes began to be used relatively recently. Previously it was believed that they were quite cold and were not able to provide optimal level insulation indoors. But today they have begun to be supplemented with warm radiators for heating.

Technically pour over the ground concrete base It’s possible even without any experience. Floors of this type are a regular screed, which is located directly on the soil or a small cushion. And so that it can withstand high loads, its thickness exceeds 10 cm. This parameter can vary greatly wide range, since it depends on several factors.

Concrete perfectly permeates moisture and temperature. Therefore, such surfaces should only be used in private houses that are heated in winter. If such a structure is left in the cold, then sooner or later the water will simply tear the material and cracks will appear. This will lead to failure of the upper decorative covering, which also begins to collapse after a certain time.

To eliminate these phenomena, it is necessary to additionally form several layers of thermal insulation on all sides of the screed.

Advantages and disadvantages

The soil itself is a moving structure that affects almost everything that is located on it. But concrete floors on soil have many advantages over other types of bases:

1. Relatively low cost. You can form a screed at any time by simply preparing a mixture from materials available in any store.
2. The surface after hardening does not require additional leveling or strengthening. It can easily be used for the installation of decorative flooring products.
3. The material adheres tightly to the soil, which eliminates the formation of fungus due to the absence of a large amount of air.
4. Durability. Concrete surfaces last much longer than wood or reinforced concrete slabs.

But the floor on the ground does not differ in unique technical characteristics, since it has several disadvantages:

1. After laying a layer of mortar, a significant amount of usable space is lost. Sometimes this figure can reach 60 cm in height.
2. The need for high-quality waterproofing. This, in turn, affects not only financial costs, but also the labor intensity of operations.
3. Floors are not compatible with columnar and pile foundation. This approach does not allow achieving high strength and protection of the material from damage.
4. If communication channels are located inside the screed, then their repair will be expensive and labor-intensive.

Floor requirements

Constructions of this type represent an important building element. Therefore, several standards and rules have been developed for it. All these standards can be found in document SNiP 2.03.13-88. Concrete floors on the ground must meet the following regulatory requirements:

• Installation of the screed is only possible on soils that are stable and high in density. It is not recommended to fill when the soil may sag under the influence of groundwater or heavy rainfall. The soil must be thoroughly compacted before installation.

• Application of bedding is only possible on compacted bases. It is correct to use sand or gravel for such purposes. Their thickness is calculated based on the loads on the floor.
• If there are many capillary channels in the soil, then it is advisable to lay waterproofing on top of the bedding. If this is not done, moisture will rise up and destroy the bottom layer of concrete in the living room. Such operations should be undertaken when the groundwater level is no deeper than 2-3 m.
• Thermal insulation is not used for unheated non-residential premises. If the house is planned to be heated, it is imperative to supplement the floor with a thick layer of thermal insulation materials.

Device

The concrete floor is a multi-layer structure. This structure allows for an optimal balance of strength and durability. This “pie” consists of the following layers:

• backfilling. The lowest layer, which is the soil itself. Please note that during the construction of floors, the turf is removed, and in its place is filled with dense soil without plant impurities. It can be compacted using special vibrating machines.
• Litter. The main components of this layer are sand or crushed stone (supplemented by a geotextile layer). Optimal thickness materials after pressing is about 40 cm.

• Footing. This layer is a concrete screed, about 10 cm thick. It is protective and supportive, and also additionally levels the base.
• Waterproofing layer and insulation. Special films based on polyethylene, as well as liquid bitumen and others are used as waterproofing. Optimal insulation Expanded polystyrene foam up to 10 cm thick is considered. It is important to use only high-density materials (EPS and so on).

• Damper tape. It is placed around the perimeter of the foundation. It compensates for the expansion of the top concrete layer.
• Top screed. This layer is made from durable concrete, which are additionally reinforced with metal mesh. To prevent rapid cracking, so-called expansion joints are formed over the entire surface of the floor.

Please note that this concrete floor structure is not always used.

Some layers may be discarded, and crushed stone, for example, replaced with expanded clay or another product.

Making a solution

The main component of the floor is concrete, which must be prepared. You can do this with your own hands at home. The algorithm for preparing the mixture manually consists of the following sequential operations:

• Preparing the container. Initially, you should find a metal bowl where the components will be mixed. Its volume is selected depending on your needs and speed of work.

• Mixing components. To do this, determine the brand of concrete you want to use. Based on these data, the ratio of all products in the future mixture is obtained. After this, they are poured into the bowl. To make mixing easier, you can arrange the components in layers. When everything is prepared, you need to thoroughly mix the sand and gravel mixture until a homogeneous mass is obtained.
• Obtaining a solution. This process involves adding water to the resulting mixture. The liquid should be poured gradually and in small portions. During this, the components are periodically mixed to a homogeneous liquid mass. Density is determined by eye. It is important that the solution is not too liquid, as it will spread.

Pouring technology

Forming a concrete floor on the ground is a rather complex procedure that requires following the following sequence of actions:

• First of all the rough foundation is being prepared. To do this, the top layer of soil is removed, and in its place is placed dense soil, which was obtained after digging a hole for the foundation. Try to completely remove soil containing organic matter, as it will rot and sag over time. After leveling, this layer must be compacted with a vibrating plate.

• At this stage they perform laying communications. This includes water pipes, which should be located directly on the ground. The wiring is carried out according to the layout, which takes into account the location of all household appliances connected to the centralized water supply. Many experts recommend hiding pipes no more than 1 m deep. During installation, it is important to constantly monitor the quality of joining of elements, since it will be difficult to repair them after filling yourself. Electrical cables can be laid in a similar way if they need to be hidden inside the floor.

• When all communications are laid, perform laying bedding. It will serve as a base for concrete. Its thickness is about 50 cm. The gravel-sand mixture is laid in layers (crushed stone, sand). It is important to compact the material with a vibrating plate after each layer placement. A screed up to 5 cm thick must be poured on top of the sand. It will act as the basis for waterproofing.

• On top of a rough concrete floor attach special bitumen sheets. At the junction points, they should form an overlap of up to 15 cm. The material must cover the foundation itself, so that the sheets do not have to be adjusted when concreting. A layer of insulation is laid on top of the waterproofing. To do this, dense polystyrene foam is cut into sheets and evenly distributed on the surface. Try to minimize the size of the gaps at the junctions of the polymer substance.

• At this stage they perform floor reinforcement by using metal mesh. It is formed from reinforcement rods, which are connected to each other with plastic clamps or metal wire. The cell size should be approximately 10x10 cm. The best option would be reinforcement with a diameter of 4 mm, which perfectly withstands compression loads. If reinforcement is not used, the floor will quickly crack and become unusable.

Please note that the bottom of the wire should not come into contact with the insulation. Therefore, the entire mesh is raised above the surface using special plastic bosses. If it is planned to form a warm floor inside the room, then all its elements must be placed directly on the fittings.

It is important that the cable does not cross itself, as this can lead to overheating and rapid failure.

• Concreting. This procedure begins with the installation of formwork. That's all for this vertical supports are located only in the middle of the room, dividing it into zones. They should not be mounted along walls. Please note that it is not recommended to trim the mesh. The wire should go into the formwork, in which cuts should be made under it along the entire length of the structure.

When everything is ready, the floor is poured from scratch. It is important here to do everything at once in order to form a monolithic structure. Alignment of the screed occurs according to previously installed beacons or relative to marks on the walls. Before pouring, be sure to secure damper tape along all walls. It can be purchased at any hardware store or made from small pieces of polystyrene foam.

Floor finishing occurs only after completely dry concrete. This period can last from 1 to 2 months depending on the thickness of the screed.

If desired, you can sand the surface and get quality foundation under laminate or parquet.

Floors on the ground - universal method installation of a warm and reliable foundation in the house. And they can be done at any groundwater level and type of foundation. The only limitation is the house is on stilts. In this article we will describe in detail all the layers of the “floor pie” and show how to organize it with your own hands.

Concrete floors on the ground imply the absence of basements or gaps for ventilation in the underground.

At its core, it is a multi-layer cake. Where the lowest layer is the soil, and the topmost is the floor covering. At the same time, the layers have their own purpose and strict sequence.

There are no objective restrictions for organizing the floor on the ground. High groundwater is not an obstacle to this. Their only weak point is production time and financial costs. But on such floors you can put brick or block walls, and even heavy equipment.

Correct “floor pie” on the ground

The classic floor pie on the ground implies the presence of 9 layers:

1. Prepared clay;
2. Sand cushion;
3. Crushed stone;
4. Polyethylene film;
5. Rough concreting;
6. Waterproofing;
7. Insulation;
8. Finish screed;
9. Flooring.

We deliberately did not indicate the thickness of each layer, so as not to set any strict restrictions. Below, approximate values ​​and influencing factors will be indicated. But first we would like to point out a very important point: The groundwater level can change very seriously in a fairly short period of time.

In our practice, there have been cases when, within 5-7 years, dry semi-basements and cellars in private houses had to be filled up, because groundwater completely flooded the underground premises. Moreover, this phenomenon was observed not in one individual house, but in an entire block of private buildings (40-60 houses).

Experts explain such phenomena by improper drilling of water wells. Such actions lead to mixing of aquifer lenses, rupture of layers and changes in aquifers. Moreover, they can drill a well quite far from your home. So pay close attention to the purpose of each layer of the floor pie on the ground and do not think that there are unnecessary elements here.

1. Prepared clay. The purpose of this layer is to stop groundwater. In general, the three bottom layers of the floor pie are intended for exactly this. Of course, if you are filming fertile layer, have reached the layer of clay, then there is no need to bring it and fill it up, only a little preparation is required. But more on that in due time.
2. Sand. There are no special requirements for sand. You can use any, for example, quarry or even unwashed.
3. Crushed stone. Large, fraction 40-60 mm.

These three layers are responsible for cutting off the capillary rise of water. A layer of clay cuts off the main access, sand weakens the capillary rise of water and weakens the pressure of the upper layers, and crushed stone does not allow water to rise at all. At the same time, each layer must be compacted. The thickness of each layer is at least 10 cm. Otherwise, there is no point in filling it up. But the maximum height needs to be explained in more detail. The fact is that tamping is most often done homemade devices. The weight of such instruments is 3-5 pounds.

It has already been empirically proven that compacting a layer of crushed stone, sand or clay more than 20 cm. hand tools impossible. Therefore, the thickness of one of the first three layers is maximum 20 cm. But, if you need to make the floor pie higher, then tamping can be carried out in two stages. First, 15-20 cm of sand is poured and compacted well. Then another layer of the same thickness is poured and compacted again.

The order of occurrence of the clay-sand-crushed stone layers cannot be changed. The reason here lies in the fact that if sand is poured on top of crushed stone, then after some time it will seep through it. Which in turn will lead to subsidence and destruction of the concrete layer, and then deformation of the entire floor.

1. Polyethylene film. Be sure to take the film with your sleeve and lay it without cutting. That is, there will actually be two layers of polyethylene. It is intended solely to prevent the concrete solution from flowing into the crushed stone.
2. Rough concreting. Minimum thickness layer 8 cm. Sand can be taken from a quarry, but it must be washed. But crushed stone is required with a fraction of 10-20 mm. This layer will be the basis for the final part of the floor on the ground. Dispersed steel fiber reinforcement is recommended.
3. . When carried out correctly preliminary work, ordinary roofing felt without powder can handle waterproofing quite well. If in doubt, you can lay roofing felt in two layers.
4. Thermal insulation. Here it is recommended to use only Extruded Polystyrene Foam (EPS). Thickness should be determined depending on the region and climatic conditions. But we do not recommend using EPS with a thickness of less than 50 mm.
5. Finish screed. Depending on the project, water heated floor pipes or electric floor heating cables can be integrated into it. Only river sand is used. This layer must be reinforced. Dispersed reinforcement with steel fiber is possible. The thickness of the screed is at least 50 mm.
6. Flooring. Concrete floors on the ground, organized in a private house in this way, have no restrictions on the use of floor coverings.

Installing a floor on the ground with your own hands

Before starting work, calculate the excavation depth. The calculation is carried out in reverse order. That is, the threshold is taken as zero front door. Then they begin to add up the thickness of each layer. For example:

• Linoleum – 1 cm;
• Finish screed – 5 cm;
• Insulation – 6 cm;
• Rough screed – 8 cm;
• Crushed stone – 15 cm;
• Sand – 15 cm;
• Prepared clay – 10 cm.

The total depth turned out to be 60 cm. But keep in mind that we took the minimum values. And each building is individual. Important: add 5 cm of depth to the result obtained for you.

Excavation is carried out to the calculated depth. Of course, the fertile layer will be removed, but clay may not always be below. Therefore, we will describe the process of organizing a floor pie on the ground in full.

Before filling the layers, draw level marks with chalk in 5 cm increments on all corners of the foundation. They will make the task of leveling each layer easier.

Soil compaction

Any clay will do for these purposes. It crumbles in an even layer and is generously moistened before compaction. aqueous solution liquid glass. The proportions of the solution are 1 part liquid glass and 4 parts water.

To compact the first three layers, you can use a one and a half meter piece of timber 200x200. But the process will be better if you do special device. To do this, to a one and a half meter segment metal pipe, A piece of channel is welded in a T-shape. The lower part of the channel should not have an area of ​​more than 600 cm2 (20 by 30 cm). To make the tamper heavier, sand is poured into the pipe.

The compacted layer of prepared clay is well moistened with cement laitance. To prepare it, 2 kg of cement is dissolved in 10 liters of water. Make sure that no puddles form on the surface of the clay. That is, it should be fairly even.

Almost immediately after the cement comes into contact with liquid glass the chemical process of crystallization begins. It goes away quite quickly, but during the day you should not disturb the crystal formation in any way. Therefore, do not walk on clay, but rather leave the work for a day for a technological break.

The main layers of the “floor pie”

Sand. After a day, you should start filling the sand. At the same time, try not to walk on the first layer. Pour sand and step on it. Chemical processes Between liquid glass and cement there will be another week and a half. But air access is no longer needed for this, and water is present in the clay. Having poured a layer of 15 cm, feel free to step on it and compact it.

Crushed stone. It is scattered in an even layer over the surface of the sand and also compacted. Pay attention to the corners. It is very important that after compacting the surface is as smooth as possible.

Polyethylene film. It is laid with a 10 cm overlap and taped. A small, 2-3 cm bend on the walls is allowed. You can walk on the film in soft shoes with extreme caution. Remember that polyethylene film is not, but only a technological layer to prevent laitance from flowing into crushed stone.

Rough concreting.“Lean concrete” is prepared in the following proportion: M500 cement – ​​1 hour + sand 3 hours + crushed stone 4 hours. For dispersed reinforcement, add steel fiber based on 1 kg. fiber per 1 cubic meter of concrete. Try to level the freshly poured solution, following the corner marks. On a flatter surface, it will subsequently be more convenient to lay layers of waterproofing and insulation.

48 hours after pouring, the concrete must be reinforced. To do this, you will need a solution of liquid glass in water (1:10) and cement. First, the solution is passed over the entire surface. You can use a roller, or you can use a spray bottle. Then they dust the concrete with a thin layer and immediately begin to rub the cement into the surface. The most convenient way to do this is by grouting.

This procedure increases the strength of concrete by an order of magnitude, and in combination with liquid glass makes it as waterproof as possible. The concrete will mature within one and a half months, but by next stage work can begin within a week.

Insulation and waterproofing

To create a waterproofing layer, the floor surface is cleaned and treated with liquid bitumen. Ruberoid is laid overlapping, with an allowance of 3-5 cm. The joints are carefully soldered using a construction hair dryer. Wall allowance 5 cm. IMPORTANT: Make sure that the roofing material fits into the corners and do not leave any voids. The second layer of roofing felt is laid offset by half the width of the roll. During waterproofing work, it is best to walk on the surface in shoes with soft soles (sneakers, galoshes).

For thermal insulation, the best option is extruded polystyrene foam. A 5 cm thick EPS layer replaces 70 cm of expanded clay. And in addition, EPS has a practically zero water absorption coefficient and quite high compressive strength. We recommend laying 3 cm thick EPS in two layers. In this case, the top layer is laid with an offset. This method guarantees the absence of cold bridges and increases the thermal insulation properties of the floor pie. The joints between the EPS boards are glued with special tape.

Proper thermal insulation of the floor pie is an extremely important component for the energy efficiency of the entire house as a whole. Up to 35% of heat escapes through the floors! Even if the floors do not produce heat themselves (warm floors), they should be thermally insulated as much as possible. This will allow you to save quite impressive amounts on heating in the future.

Floor screed

Glue along the room, 15-20 mm thick. In this case, the lower part must be glued to the EPS boards. To reinforce the floor on the ground in residential premises, use a masonry mesh with cells of 100x100 mm. Wire thickness 3 mm. The mesh must be placed on supports so that it is approximately in the middle of the screed layer. To do this, it is placed on special stands. But you can use regular PET bottle caps.

Installation of beacons is possible, but in combination with reinforcing mesh, this will create a rather bulky and extremely fragile structure. After all, if you rigidly fasten the mesh, this will require additional costs for fastening and will require violating the integrity of the EPS. And if the fittings are not fixed, then it can easily change the levels of the beacons. Therefore, it will be more convenient to fill this layer and then level it with a self-leveling screed.

For the finishing screed, the solution is diluted in the proportion of 1 part M500 cement + 3 parts river sand. The work is carried out promptly. To roughly level the surface, you can focus on the corner marks.

After pouring the finishing screed, it should be allowed to gain strength for 3-5 days. With a thickness of 5 cm, the ripening period of this layer will be 4-5 weeks. During this time, regular wetting of the surface with water is required.

Acceleration of the cement hydration process is unacceptable! After about a month, you can check the degree of readiness. To do this, in the evening, take a roll of dry toilet paper, place it on the floor and cover it with a saucepan on top. If in the morning the toilet paper is dry or slightly damp, then the layer is already ready. You can level the floor with a self-leveling screed.

The self-leveling screed is diluted according to the manufacturer's instructions and poured onto the surface of the concrete floor. When the work is carried out scrupulously, height differences do not exceed 8-10 mm. Therefore, a minimal amount of self-leveling screed is required. It dries quite quickly. And after 1-2 days the floor pie on the ground will be completely ready for laying the floor covering.

Updated: 02/19/2019

May differ from , although specific differences depend on:

• groundwater level;
• planned load on the floor;
• use of "warm floor" technology.

If The groundwater lie closer than 2 meters from the surface, then the presence of waterproofing is mandatory, as well as “pillows” made of sand and coarse crushed stone. The use of a “warm floor” implies a 2-centimeter thermal gap between the concrete and the walls, otherwise the filling may be damaged during operation.

The filling procedure must be carried out in compliance with a number of requirements:

• the soil should not be mobile;
• groundwater must be at least 5 meters away;
• the ground must be dry.

In winter, the room must be heated, otherwise the structure may deform due to soil freezing and, as a result, mechanical loads will increase.

Note! If we're talking about If the house is still under construction, then the installation of the floor should begin only after the roof is ready. This way, subsequent work will be completed to the highest possible quality.

Stage 1. Determination of the “zero” level

First, determine “zero” (mortar filling level), which should be equal to the bottom of the doorway, and mark it around the perimeter. To do this, make marks a meter from the bottom of the opening (as shown in the diagram) and transfer them to the walls of the entire room (obviously, it is better to use a laser level for this). Next, measure back 1 meter down from these marks and draw a second line - it will be the “zero” along which the floor will be filled. To simplify the procedure, hammer nails in the corners and stretch the cord.

Stage 2. Preparing the base

After determining the “zero” level, take out construction garbage and remove the fertile soil layer. The floor in our case will be a multi-layer “pie” approximately 35 cm thick. Therefore, remove soil until the depth from the “zero level” is equal to the thickness of the future “pie”.

Next, compact the surface. It is advisable to use a vibrating plate for this, although in its absence you can take an ordinary meter-long log, nail a board on the bottom, and two handles on top, and use such a tool to compact the soil. The result should be an even and, most importantly, dense base. There should be no traces left from walking on such a foundation.

Note! If it happens that the soil level is lower than 35 cm, then simply remove a little of the fertile layer, compact it and fill it with sand to the desired level. Then compact the sand itself.

To increase the waterproofing properties of the base, cover the “native” soil first with a layer of clay, then sand, add water and compact thoroughly.

Stage 3. Further backfilling

Once you've finished with the base layer, start adding gravel. Fill the material with a layer of 10 cm, water and compact. To make it easier to control the thickness, drive a number of pegs of the required thickness into the base and align them to the same level. When compaction is complete, pull them out.

Cover the sand with a similar layer of crushed stone (the fractions of the latter should be approximately 5 cm). Compact the crushed stone, sprinkle a thin layer of sand on top, level and compact. If you notice that there are protruding edges of crushed stone left on the surface, then remove them or lay them in a different way. Remember that the result should be a flat plane without any corners.

Note! Check each filled layer with a mounting level.

Stage 4. Isolation

For waterproofing, you can use an insulating membrane or ordinary polyethylene film, the thickness of which will be equal to 200 microns. Cover the entire area of ​​the room with the material, with an overlap of several centimeters, and place the edges on the walls slightly above the “zero” level. Seal all joints with tape.

There are quite a lot of materials for thermal insulation, you can choose any one. So, for a concrete floor it may be suitable:

• expanded clay;
• isolon;
• Styrofoam;
• moisture-resistant plywood;
• mineral wool, basalt wool;
• perlite;
• expanded polystyrene (both regular and extruded).

Stage 5. Reinforcement

In order for the future floor to be strong enough, it should be reinforced. You can use both metal and plastic mesh for this, and if large loads are planned, then tie together reinforcing rods 0.8-1.6 cm thick by welding.

Do not lay the reinforcement directly on the foundation pie. Use small pegs (“chairs”) - lay them in rows, placing a plate cut from asbestos under each one to raise it to a height of at least 20 mm. In this case, the reinforcement will be inside the concrete screed and forms one whole with it.

Note! Using plastic mesh, pull it onto pegs driven into the ground for a similar purpose.

Stage 6. Formwork and guides

In order to maintain “zero” and make the filling procedure easier, install guides. First, divide the room into equal sections no more than 2 m wide, then divide them with guides. To make the latter, you can use either beams or boards, or iron pipes. Make sure that the height of the guides is equal to the “zero” level. Secure them with thick cement mortar.

Then proceed to install the formwork between the guides, forming special “cards” (identical rectangles, the dimensions of which should be selected so that each of them is poured in one go). The use of “cards” will significantly simplify the work, especially over a large area, and will help maintain “zero”. To make “cards,” use fresh boards (not dry) or moisture-resistant plywood.

Note! Align the guides with the formwork to the “zero” level, otherwise the floor may turn out uneven. Use for this building level. Also treat these elements with special oil (such as Agat-S5) so that you can easily remove them from the concrete.

Stage 7. Preparing the solution and pouring

Fill the solution in a maximum of two passes, although it is advisable to do it in one. For this purpose, you can order “factory” concrete (it will be delivered immediately to large quantities) or do the cooking yourself (it will cost less). If you resort to the second option, you will need:

• shovel;
• concrete mixer (you can rent it);
• “four hundredth” or “five hundredth” cement;
• crushed stone;
• sand;
• one assistant.

Concrete grade	Mass composition, C:P:SH, kg	Volumetric composition per 10 liters of cement P/Shch, l
100	1: 4,6: 7,0	41/61	78
150	1: 3,5: 5,7	32/50	64
200	1: 2,8: 4,8	25/42	54
250	1: 2,1: 3,9	19/34	43
300	1: 1,9: 3,7	17/32	41
400	1: 1,2: 2,7	11/24	31
450	1: 1,1: 2,5	10/22	29

Concrete grade	Mass composition C:P:SH, kg	Volumetric composition per 10 liters of cement P/Shch, l	Amount of concrete from 10 liters of cement, l
100	1: 5,8: 8,1	53/71	90
150	1: 4,5: 6,6	40/58	73
200	1: 3,5: 5,6	32/49	62
250	1: 2,6: 4,5	24/39	50
300	1: 2,4: 4,3	22/37	47
400	1: 1,6: 3,2	14/28	36
450	1: 1,4: 2,9	12/25	32

Video - How to mix concrete mixture or how to make concrete

To prepare the solution, pour cement, sand, crushed stone and water into a concrete mixer in a ratio of 1:2:4:0.5 and mix everything until a homogeneous mass is obtained. Fill in ready solution from the corner opposite the entrance door. After filling several “cards”, level the solution with a shovel and distribute it around the perimeter. To compact concrete, use a vibrator - it will not only compact the mixture, but also remove air bubbles from it.

Having processed the filled cards with a vibrator, proceed to leveling. To do this, you will need the 3-meter rule - place the tool on the guides and pull it towards you. This will remove excess solution. In the leveled “cards”, dismantle the formwork and fill the resulting voids with concrete. When the entire floor is filled, cover it with plastic wrap and leave for two to three weeks to dry completely, do not forget to periodically moisten the surface with water.

After this time, you can apply a self-leveling mixture to the finished floor, which can smooth out minor defects and make the surface perfectly flat. Wait another three days for this mixture to dry.

This floor is distinguished by the presence of a layer of air between the soil and the screed, which is advisable in areas where the level of soil moisture is high, that is, if groundwater is closer than 2 meters from the surface. This technology can also be used when the site is located in the northern region of the country, and the heating system will operate periodically.

Note! It is very important that the ground level is at least 10-15 cm below the concrete floor. If the gap is large, heat loss will increase, and if it is smaller, ventilation will be less effective.

Let's look at how the flooring technology in this case differs from that described above.

Stage 1. Preparation

First prepare the soil.

Step 1. Remove vegetation layer and fill it with regular soil instead. Pour water over the soil and compact it so that the resulting layer height is approximately 15 cm.

Step 2. Fill the top with gravel and tamp again.

Step 3. Cover the finished base with a crushed stone-lime mixture (although it can be replaced with broken bricks or, for example, construction waste).

Next, at the same distance from each other (about 70-100 cm), install brick columns under the logs. Use red brick for this, but in no case silicate brick. Having installed the posts, cover each of them with roofing felt for waterproofing, and on top of it attach 3-centimeter thick bars, pre-treated with an antiseptic.

Stage 3. Lags

To make logs, use log halves, also coated with an antiseptic. The joints between the joists should be located above the columns, but place the outer joists 2-3 cm from the surface of the walls. Check the level of the joists and place them under them if necessary. wooden blocks. Remember: the maximum permissible horizontal unevenness in this case is only 3 mm.

Note! Instead of bricks for posts, you can use metal pipes.

Stage 4. Next steps

Nail the floorboard to the joists. Try to ensure that the boards fit as tightly as possible. If you wish, you can use a more reliable scheme:

• 1st layer – uncut boards;
• 2nd layer – waterproofing;
• 3rd layer – floorboards.

The subsequent stages of filling are no different from those described above.

Note! The underground requires high-quality ventilation, so make ventilation windows measuring 100x100 mm in the corners. Cover the windows with metal bars. Equip special vents in the basement (at least two per room).

Video - Arranging a floor on the ground

This set of rules applies to the design of floors in industrial, warehouse, residential, public, administrative, sports and domestic buildings. Download for free