Often ribbed prefabricated monolithic ceilings. Basic rules for the installation of monolithic floors Stage #8. Sheathing of the ceiling from below and from above with finishing coatings

Monolithic reinforced concrete floors are still of limited use due to their high labor intensity. They are used in cases where it is necessary to cover an atypical room with atypical dimensions, as well as in monolithic buildings.

Monolithic floors are made of beams (ribbed) and beamless in the form of a smooth slab (Fig. 5.4).

Fig.5.4. Structural schemes of monolithic reinforced concrete floors:

a - ribbed; b - caisson; in - beamless; 1 - plate; 2 - beams; 3 - columns; 4 - column capital

5.1.4. Ceilings by beams

Beam ceilings are used in low-rise construction (in wooden and stone buildings), in the reconstruction of old buildings by replacing wooden beams with more durable metal or reinforced concrete ones.

According to the material, the beams are divided into wooden, reinforced concrete and metal.

Ceilings on reinforced concrete beams. Ceilings on reinforced concrete beams consist of beams laid on load-bearing walls with a distance in the axes of 600, 800, 1000 mm, inter-beam filling and floor (Fig. 5.5).

The depth of support of the ends of the beams on the walls or girders is taken at least 150 mm. The ends of the beams on the supports are anchored, and the gaps between the beam and the nest walls to a depth of 40-60 mm are sealed with mortar. Inter-beam filling (Fig. 5.6) consists of a run-up, which is a flooring of lightweight concrete slabs and a soundproof (heat-insulating) layer. The seams between the rolling elements and the beams are carefully filled with mortar or glassine is laid on top of the rolling. Soundproofing is usually performed from a layer of slag or sand with a thickness of at least 60 mm. From below, the roll and beams are rubbed with mortar. This design is used for plank floors along the logs. When installing other types of floors, such as cement, requiring a continuous gesture

Fig.5.5. Prefabricated reinforced concrete beams and details of their support:

a - plan for the location of floor beams; b - general form beams; 1 - beam;

2 - steel anchor; 3 - steel structure; 4 - mounting loop; 5 - concrete embedment

After some preparation, the space between the beams is filled with slag, along which a layer of cinder concrete with a thickness of at least 40 mm and a floor are laid (Fig. 5.6d). More appropriate in these cases are rolls of double-hollow lightweight concrete stones - liners that have sufficient soundproofing properties and require only careful filling of the joints with mortar (Fig. 5.6 e).

Overlaps by metal beams. Currently, metal beams are used only in exceptional cases in the repair and reconstruction of buildings.

Steel beams (usually I-beams) are located at a distance of 1-1.5 m from each other. The depth of support of their ends on the walls is 200-250 mm.

Fig.5.6. Prefabricated beam construction

reinforced concrete elements:

a - general view; b - lightweight concrete slab; c - lightweight concrete stone insert; d, e - floor options with mineral floors; 1 - reinforced concrete beam; 2 - reel from lightweight concrete slabs; 3 - waterproofing layer; 4 - sound insulation; 5 - soundproof gasket; 6 - log; 7 - plank floor; 8 - slag; 9 - slag concrete thickness

40 mm; 10 - cement floor 20 mm thick; 11 - grouting with mortar

To increase the area of ​​pressure on the masonry in order to protect it from collapse, concrete pads or steel linings are placed under the ends of the beams. The ends of the beams are anchored into the masonry of the walls and, if necessary, insulated with felt, followed by sealing the gaps around the perimeter of the nest with concrete (Fig. 5.7).

Inter-beam filling can be made of reinforced concrete prefabricated or monolithic slabs, and in some cases from brick vaults.

Fig.5.7. Ceiling construction on steel beams:

a - supporting the ends of the beams on the walls; b - anchor fastening detail; c - overlap with filling with a reinforced concrete monolithic slab; g - the same, brick vaults;

1 - steel beam; 2 - steel anchor; 3 - concrete pad; 4 - bolt; 5 - sealing with cement mortar; 6 - reinforced concrete monolithic slab; 7 - lightweight concrete; 8 - ceramic tiles over a layer of cement mortar; 9 - brick vault; 10 - soundproof layer; 11 - two layers of roofing; 12 - plank floor along the logs; 13 - steel mesh; 14 - plaster with cement mortar

Overlaps by wooden beams. At present, wooden floors are allowed only in low-rise buildings and only in areas where wood is a local building material. Their advantages are the simplicity of the device and the relatively low cost. Disadvantages - combustibility, the possibility of decay and relatively low strength.

All wooden floor elements are made from coniferous forests (pine, larch, spruce, etc.). Beams are made mainly in the form of rectangular bars, the dimensions of which are established by calculation. (Fig. 5.8). The distance between the axes of the beams is taken from 600 to 1000 mm.

To support the inter-beam filling, bars with a section of 40 x 50 mm, called cranial, are nailed to the sides of the beams (Fig. 5.8). The depth of support of the ends of the beams in the sockets of the stone walls must be at least 150 mm (Fig. 5.9). The ends of the beams are antiseptic with a 3% solution of sodium fluoride or coated (except for the ends) with resin, and when embedded in the outer walls, they are additionally wrapped with two layers of roofing paper. On internal walls ah or runs under the ends of the beams, two layers of roofing felt on tar mastic are laid. The gaps between the walls of the nest and the ends of the beams to a depth of 40-60 mm are tightly sealed with mortar. The location of the wooden floor beams, as well as their anchoring, are similar to reinforced concrete beam-type floors (Fig. 5.1 c).

The filling between the beams (Fig. 5.10) consists of a board board run, lubrication on the top of the run with a clay-sand mortar 20-30 mm thick and a soundproof layer of slag or calcined earth 60 mm thick. The floors are made of boards along the logs with the device in them at the corners of the premises of metal ventilation grilles. Ceilings are plastered with lime-gypsum mortar along the strips or hemmed with sheets of dry plaster.

Fig.5.8. Structural solutions of wooden beams:

1 - bar single beam; 2 - beam composite of two bars of solid wood; 3 - a beam of glued wood; 4 - cranial bar

Rice. 5.9. Details of supporting wooden floor beams on

stone walls:

a - on outer wall; b - on the inside; 1 - external load-bearing wall; 2 - external self-supporting wall; 3 - internal load-bearing wall; 4 - wooden beam; 5 - thermal insert; 6 - two layers of roofing paper on tar mastic or antiseptic zone of the beam; 7 - an anchor made of strip iron; 8 - crutches or nails

Fig.5.10. Floor construction on wooden beams:

a - with a plank shield roll; b - the same, from hollow blocks; c - the same, from lightweight concrete blocks (slabs); d - floors in bathrooms; e - types of rollovers; 1 - beams; 2 - reel (shield); 3 - plaster; 4 - clay lubricant; 5 - backfill; 6 - log; 7 - soundproof gasket; 8 - plank floor; 9 - hollow lightweight concrete block; 10 - cranial bar; 11 - solution; 12 - gypsum board; 13 - ceramic tile floor; 14 - cement screed 20 mm; 15 - concrete preparation; 16 - two layers of roofing material on mastic; 17 - plank floor; 18 - plates; 19 - boards; 20 - false ceiling

In this article we will talk about what are the methods of erecting a monolithic floor, and you will also learn about the advantages and disadvantages of these methods. The article will talk about the basic requirements for the thickness and reinforcement of reinforced concrete floor elements.

Reinforced concrete is an almost eternal material. It creates a multitude structural elements- beams, walls, lintels. One of the most difficult, at first glance, products is overlapping. However, the complexity of the construction is fully offset by the operational properties of the finished product.

Advantages of a monolithic floor:

1. The highest load-bearing capacity of known materials.
2. The most durable of widely available materials.
3. Relatively cheap raw material (for concrete).
4. To perform the work, high qualification of the entire team is not required (1-2 leading specialists are enough).
5. Combined functions: the base of the floor of the second floor, the armored belt, the connection of all walls to each other.
6. A properly arranged monolithic structure eliminates the appearance of deformation defects (“steps”, distortions, cracks).

Disadvantages of concrete floors:

1. Labor intensity of construction. The work is connected with the installation of horizontal formwork of high strength and rigidity.
2. Accompanying material is involved, which after concreting may become unusable - plywood, flanging board, racks (wooden).
3. The heavy weight of the structure requires powerful walls and a foundation.
4. High thermal conductivity of concrete - all areas open from the outside must be insulated.
5. Concrete flooring is possible only on stone walls.

Reinforced concrete floors are suitable for permanent buildings designed for a long service life, as well as for premises that provide for a significant static and dynamic load - workshops, hotels, hostels (with partitions made of stone material).

In private construction, monolithic floor slabs are usually arranged along brick walls, since concrete walls are much more difficult to erect than brick ones.

The thickness of the monolithic slab

Due to the big specific gravity concrete (2400 kg / m 3), products from it are heavy. The mass of the product can be reduced by reducing the part of the concrete in the structure, that is, simply making it thinner. Rigidity is compensated by reinforcement. Sufficient thickness of reinforced concrete elements:

• load-bearing walls - 160 mm
• floors - 200 mm
• partitions - 100 mm

The thickness of these elements will be considered sufficient only if the rules of reinforcement are observed. Calculations and many years of practice have shown that there is an optimal balance of mass, volume, section and bearing capacity of reinforced concrete elements. Read about this below in the section "Reinforcement of floors". The sufficient thickness of the brick wall is 380 mm (1.5 bricks).

Floor formwork

Like any reinforced concrete element, the ceiling requires the installation of a form for concrete - formwork. Since the overlap has a significant area and is at a height, the formwork for it has the form of a table: a solid plane that fills the space between the bearing walls (and columns) on a spatially rigid frame of racks and slopes. There are three types of formwork, but one requirement is invariable for any of them - a reliable foundation.

Inventory formwork

Factory kit, which includes:

1. Racks - screw retractable jacks, up to 4 m long.
2. Equipment for racks - “tripods” at the bottom for the stability of a free-standing jack and a “crown” at the top for landing table beams.
3. Wooden beams - factory glued products of an I-profile 200 mm high and up to 4.2 m long.
4. Laminated plywood - sheets of plywood 18-24 mm thick, 1220x2440 mm in size, covered with a stable film, designed to create a floor plane. The coating withstands up to 40 concreting cycles.

Such a set is professional - high-rise residential buildings are built with inventory formwork. It is reliable, comfortable and designed for continuous use. The purchase of a set for the installation of one floor will not justify itself - all steel products are not cheap. Formwork rental can be a solution. The company's specialists will calculate required amount each of the elements for your object.

The undoubted advantages of this approach are the speed of formwork installation and ease of use, as well as the quality of the plane. The disadvantages include the risk of delaying the lease term.

Homemade formwork

All elements of the "table" for overlapping can be made independently from wood and some metal parts.

This method is used when the main elements - racks, beams and plane material (plywood or board) are available. This is the main advantage of the method - the use of improvised material. Obvious disadvantages:

1. Labor-intensive construction requiring advanced carpenter skills.
2. Large waste of material - up to 20% will become unusable.
3. Problematic height adjustment (“horizontal” installation).

Combined method

Provides for the partial use of inventory formwork and lumber.

In this case, you can use the factory racks with tripods and crowns, and make the beams and formwork flooring from the board. Or rent laminated plywood, and assemble the frame of the "table" from the wood at hand. There can be many combinations.

Floor reinforcement

For the installation of a reinforcing cage of a hanging reinforced concrete floor with a thickness of 200 mm, a mirror mesh of reinforcement A3 Ø 16 mm with a cell of 150-180 mm is used. When using concrete prepared on site, we recommend reinforcing the frame by using a smaller rod spacing of 150 mm. If the concrete is factory, a step of up to 200 mm is allowed. In places of support and junction of elements (support on a wall, column, capital), we recommend making reinforcements - adding rods.

Floor concreting

There are concreting rules that must be observed unquestioningly so as not to subject the structure to destruction in the future:

1. The laying of concrete in the ceiling must be done in one go. If the concrete is not placed for a long period of time, the laid concrete may seize and the new concrete will not be able to mix with it. The result is a boundary along which a crack can go.
2. When concreting in a cool period (0...+5 °C), use special anti-frost additives. Read more about winter concreting in this article.
3. Be sure to use vibrators - deep or surface. Without vibration, concrete has 40-50% of the design strength. You will find more information about concreting in our article.
4. The ceiling formwork is dismantled no earlier than 28 days after concrete is laid.

Ceilings from prefabricated reinforced concrete (floor slabs).

	To date, reinforced concrete slabs are the most commonly used type of interfloor ceilings. According to their bearing capacity, they are divided into three main groups: Bearing capacity: 400 kg/m2 or 4 load Bearing capacity: 600 kg/m2 or 6 load with a capacity of 800 kg / m2, with very rare exceptions, you can find 600 kg / m2 and not find 400 kg / m2 at all. And along with this, there is SNIP 2.01.07-85 "Loads and Impacts", which determines the necessary and sufficient bearing capacity of floors, depending on the type of premises. In accordance with SNIP (clause 3.11 table 3), the bearing capacity of the floors of an apartment in a residential building is 150 kg / m2, and the most great importance is 500 kg/m2 and is allocated for book depositories, archives, stages of entertainment enterprises, stands for standing spectators, as well as for premises for raising cattle. Now let's figure out what the bearing capacity of 800 kg / m2 means in relation to the house in question. Let's take for example the most loaded room, namely the Kitchen-Living Room (with an area of ​​27.3 m2). When using reinforced concrete slabs, the bearing capacity of this room will be: 27.3 m2 * 800 kg / m2 \u003d 21,840 kg if we subtract the weight of furniture and interior elements from this value (maximum 500 kg), then we get a residual bearing capacity of 21,340 kg. Now let's determine how many people can withstand such an overlap with an average person weighing 100 kg. Number of people = 21,340 kg / 100 kg = 213 people! It is clear that such a number of people in this room is simply not fit. If we talk about the possibility of this room from the point of view of the people present, then this is no more than 20 people at the "peak" load. In other words, you get a safety factor of 10! In civil engineering, the safety factor does not exceed 0.5, and for military designers / builders it does not exceed 5!

	In fact, using reinforced concrete slabs, you get a high bearing capacity, the value of which exceeds the standard by 5 times! At the same time, under no circumstances will you use a high bearing capacity "for its intended purpose", since there is not enough space in the room to place a significant load on it. From point of view fire safety, sound insulation, thermal insulation, the option of reinforced concrete slabs does not stand out in any way relative to other types of floors. It is on the basis of the foregoing that the standard for bearing capacity for apartments in residential buildings is prescribed at the level of 150 kg / m2. If we carry out similar calculations, but in accordance with the standard value, then we will get: 27.3 m2 * 150 kg / m2 = 4,095 kg if we subtract the weight of furniture and interior elements from this value (maximum 500 kg), then we will get the residual load-bearing capacity 3,595 kg. Now let's determine how many people can withstand such an overlap with an average person weighing 100 kg. Number of people = 3,595 kg / 100 kg = 36 people! It is clear that such a number of people in this room is simply not fit. If we talk about the possibility of this room from the point of view of the people present, then this is no more than 20 people at the "peak" load. In other words, you get a safety factor of 1.8! Let me remind you that in civil engineering the safety factor does not exceed 0.5, and for military designers / builders it does not exceed 5! That is why the standard of 150 kg / m2 is sufficient for the normal operation of residential premises! P.S. When designing lightweight economical floors from LVL beams, we lay down the bearing capacity of 180 kg / m2, thereby slightly exceeding the standard and getting a safety factor of at least 2!

Calculation of costs for the installation of a precast concrete floor over a cold underground using floor slabs of the PNO series. The calculation also includes materials for thermal insulation and leveling the base under fine finish gender.

1. Plate PNO 1m2 / 1125 rubles 2. Mortar for joints M200 0.126tn / 315 rubles 3. Leveling screed M200 thickness 50mm 0.100 tons / 250 rubles 4. Extruded foam 5. Vapor barrier film 1m2 / 22 rubles 6. Reinforcing mesh 200x200x5mm 1m2 / 60 rubles 7. Leveling screed M300 thickness 50mm 0.100tn / 260 rubles 8. Finishing screed 5mm 0.0075tn / 203 rubles Total, the cost of materials for 1m2 = 2,969 rubles

1. Installation of PNO plates 1m2 / 600 rubles 2. Concreting of joints of slabs 1pc / 288 rubles 3. Performing a leveling screed M200 thickness 50mm 1m2 / 400 rubles Total, the cost of work for 1m2 = 2,488 rubles

Total materials and work for the installation of prefabricated reinforced concrete floors: 5 407-00 rub / m2.

Ceilings from monolithic reinforced concrete.

Scope: Interfloor overlappings in construction.

We consider the cost of erecting 1m2 of the floor structure.

Calculation of expenses for the device of overlapping from monolithic concrete above the cold underground. In addition to the material of the supporting structure, the calculation also includes materials for thermal insulation and leveling the base for finishing the floor.

1. Ready-mixed concrete B 25 1m2 / 880 rubles 2. Fittings (12mm and 6mm) 0.02tn / 500 rubles 3. Extruded foam listirol, thickness 150mm 0.150m3 / 734 rubles 4. Vapor barrier film 1m2 / 22 rubles 5. Reinforcing mesh 200x200x5mm 1m2 / 60 rubles 6. Leveling screed M300 thickness 50mm 0.100tn / 260 rubles 7. Finishing screed 5mm 0.0075tn / 203 rubles 8. Formwork rental for a month 1 unit / 400 rubles Total, the cost of materials for 1m2 = 3,059 rubles

1. Installation / dismantling of formwork 1m2 / 600 rubles 2. Installation of arm. frame 0.02 tons / 200 rubles 3. Concrete placement taking into account cost of a concrete pump 1m2 / 580 rubles 4. Laying extruded foam polystyrene, thickness 150mm 1m2 / 100 rubles 5. Laying vapor barrier films 1m2 / 100 rubles 6. Installation of reinforcing mesh 1m2 / 150 rubles 7. Performing a leveling screed M300 thickness 50mm 1m2 / 600 rubles 8. Finishing screed 1m2 / 200 rubles Total, the cost of work for 1m2 = 2,530 rubles

Total materials and work for the installation of a monolithic ceiling: 5 589-00 rub / m2.

Ceilings on wooden beams.

Below is a cost estimate for a ceiling device using a classic edged lumber - wooden beam. The span between the supports is 4.7 meters. In costing also included are materials for thermal insulation and leveling the base for finishing the floor. wooden elements roof structure made of coniferous wood with moisture no more than 20%, pre-treated protective compounds in accordance with the requirements SNiP 2.03.11-85 "Protection of building structures against corrosion", chapter 3 " wooden structures", as well as the requirements of SNiP 2.01.02-85 “Fire safety standards”, clause 1.8. For a span of 4.7 meters, with a center distance of 500mm when using a wooden beam 200 * 100 mm, the following overlap indicators are provided: Bearing capacity 300 kg/m2, Weight of floor structures 140 kg/m2 total "free" bearing capacity of the floor 160 kg/m2 (according to SNiP ”Loads and impacts” for residential buildings the standard is 150 kg/m2). In the calculation below, the center distance between the beams is assumed to be 625 mm to ensure waste-free laying of the DSP slab, 1250 mm wide. Lumber of natural moisture is deformed in the process of shrinkage and loss of moisture, while the height difference of the floors reaches 10 mm / 1 linear meter, therefore, the calculation provides for leveling screed 50 mm thick.

We consider the cost of erecting 1m2 of the floor structure.

Calculation of costs for the installation of a wooden beam ceiling over a cold underground. In addition to the material of the supporting structure, the calculation also includes materials for thermal insulation and leveling the base for finishing the floor.

1. Lumber 1.97 m3 / 15760 rubles 2. Fasteners 1pc / 3600 rubles 3. Fire bioprotection 1pc / 7800 rubles 4. TsSP 20mm 39m2 / 13380 rubles 5. TsSP 10mm 39m2 / 8350 rubles 6. URSA PureOne 200mm 7.8m3 / 11270 rubles 7. Vapor barrier and adhesive tape 1pc / 2000 rubles 8. Leveling screed M300 thickness 50mm 3.9 tons / 10140 rubles 9. Finishing screed 5mm 0.29tn / 7920 rubles Total cost of materials for 39.25 m 2 = 80,220 rubles

1. Installation of the frame of floors 350 rubles / 13650 rubles 2. Fire bioprotection 200 rubles / 7800 rubles 3. Installation of DSP 10mm 200 rubles / 7800 rubles 4. Installation of DSP 20mm 200 rubles / 7800 rubles 5. Laying PureOne insulation 200 rubles / 7800 rubles 6. Laying vapor barrier. films 100 rubles / 3900 rubles 7. Performing a leveling screed M300 thickness 50mm 600 rub / 23400 rub 8. Performing the finishing screed 200 rubles / 7800 rubles Total cost of workfor 39.25 m 2 = 79,950 rubles

Total materials and work for the installation of floors on wooden beams: 4 081-00 rub / m2.

Ceilings on beams from LVL beams.

Scope: Interfloor overlappings in construction, frame housing construction, truss system.

Below is a cost estimate for a floor installation using LVL beams. The span between the supports is 4.7 meters. The calculation also includes materials for thermal insulation and leveling the base for finishing the floor. For a span of 4.7 meters, with a center distance of 625mm when using a beam LVL beam 240*45 The following coverage indicators are provided: Load bearing capacity 300 kg/m2 Weight of floor structures 55 kg/m2, total "free" bearing capacity of the floor 245 kg/m2 (according to SNiP "Loads and Impacts" for residential buildings standard 150 kg/m2). In the calculation presented below, the center-to-center distance between the beams is assumed to be 625 mm to ensure waste-free laying of the DSP slab, 1,250 mm wide To simplify the calculations, the following costs are given for a room of 8.3x4.7 m.

We consider the cost of erecting 1m2 of the floor structure.

Calculation of costs for the installation of a ceiling from LVL beams over a cold underground. In addition to the material of the supporting structure, the calculation also includes materials for thermal insulation and leveling the base for finishing the floor.

Total materials and work for the installation of flooring on beams from LVL beams: 2 942-00 rub / m 2.

What's in the dry matter?

The cost of erecting a floor structure for a house according to project 83-08.

Basement floor area 124 m 2

Option 1. Precast concrete floors = 5,407 rubles / m 2 * 124m 2 = 670 468 rub

Option 2. Ceilings made of monolithic reinforced concrete = 5,589 rubles / m 2 * 124m 2 = RUB 693,036

Option 3. Floors on wooden beams = 4,081 rubles / m 2 * 124m 2 = RUB 506,044

Option 4. Overlapping on beams from LVL timber \u003d 2,942 rubles / m 2 * 124m 2 \u003d 364 808 rubles!

It is worth noting:

• glued beams do not create squeaks
• in our projects, the ends of the beams are not walled into the body of the wall, the beams are fastened on brackets, even capillary suction of moisture from the wall structure is excluded, the floor materials always remain dry, as a result - the service life of the ceiling is equal to the service life of a stone house
• the space between the beams is completely filled with mineral wool non-combustible material, the subfloor, as well as the filing of the beams, is carried out using materials that do not support combustion, DSP, fire-resistant drywall, this design has high fire resistance, because. around the beam there is no free air necessary for the combustion process.

The statement that wooden floors have the lowest cost,is a delusion.

To date, LVL timber has the best price / quality ratio. It is this material that is preferred in many private and public facilities, for example, the balconies of the Mariinsky Theater or the supporting frame of the dome of the new Oslo airport are made of LVL timber.

Additional benefits of choosing modern building technologies.

Application in construction modern materials and solutions such as LVL floor beams and truss system or porous ceramic blocks Caiman30 for external load-bearing walls, allows you to get savings not only within the current technical solution, and without degrading the necessary and sufficient consumer properties and characteristics, but also significantly reducing costs at other stages, as well as obtaining a higher quality of construction.

An example is the situation when the replacement of reinforced concrete floors with floors using LVL timber and 44 ordinary ceramic blocks for heat-efficient ceramic blocks Cayman30, for external and internal walls, significantly reduces the weight of the house.

Difference within house project 83-08 is:

• by floors 147.8 tons
• along the walls 37.9 tons,

total 185.7 tons or 30% reduction in the load on the base), which allows at the foundation stage to be limited to an economical and sufficient design option, namely a monolithic reinforced concrete pile-grillage foundation, the construction costs of which are 4-5 times lower than for the construction of a monolithic strip foundation!

Replacing a monolithic strip foundation with a monolithic pile-grillage foundation will also lead to an overall reduction in the load on the foundation, by about another 99 tons.

The total total weight reduction of building structures, and as a result of pressure on the base, is 284.7 tons.

In this article, we will consider the main types of floors and the materials from which these floors are constructed. So what are overlays? Ceilings are a structure that separates adjacent rooms in height, that is, it forms floors and separates them from attics and basements.

Basic requirements for floors

• Ceilings must have sufficient strength to withstand the load both from its own weight and useful (furniture, equipment, people in the room, etc.).The value of the payload per 1 m2 of flooring is set depending on the purpose of the room and the nature of its equipment. For attic floors, the payload should be no more than 105 kg / m2, and for basement and interfloor overlap 210 kg/m2.
• The ceiling must be rigid, that is, under the action of loads, it must not deflect (permissible value from 1/200 for attic floors to 1/250 of the span for interfloor floors).
• When installing the ceiling, a sufficient degree of its sound insulation should be provided, the value of which is established by the norms or special recommendations for the design of buildings for one purpose or another. To do this, it is necessary to carefully close the gaps at the joints of the material, in order to avoid the passage of sound from neighboring rooms located above or below.
• Ceilings separating rooms with a temperature difference of 10 Gdadus (for example, separating cold cellar from the first floor or attic from the first floor) must meet the requirements of thermal protection, that is, it is necessary to increase the thermal insulation layer.
• No floor structure, especially wood, can withstand prolonged exposure to fire, but each material has its own fire resistance value. Fire resistance limit of reinforced concrete floors - 60 min; wooden floors with backfill and lower plastered surface - 45 min; wooden floors protected with plaster, about 15 minutes; there are even fewer wooden floors not protected by fireproof materials.

Types of floors at home

• interfloor (separating residential floors, including the attic),
• basement (separating the basement from the residential floor),
• basement (separating the residential floor from the cold underground),
• attic (separating the residential floor from the unheated attic).

According to its constructive solution, the bearing part of the floors can be divided into:

• beam, standing from the bearing part (beams) and filling;
• beamless, made of homogeneous elements (flooring slabs or flooring panels).

Types of floors for the house

Beam ceilings

In beam ceilings, the supporting base is made up of beams located at the same distance from each other, on which fill elements are laid that perform enclosing functions. Beams can be wooden, reinforced concrete or metal.

Ceilings from wooden beams

In private housing construction, wooden beam ceilings are most popular, usually used in wooden and frame houses.

For wooden beams there is a limitation on the width of the span (room). They can be used for:

• interfloor ceilings - with a span width of 5 meters;
• for attic floors (with an unused attic room) with a span width of up to 6 meters. Metal beams can be used for any span width.

Wooden flooring is made of wooden beams of coniferous and hardwood. On the upper side of the beams, a flooring is made, which at the same time is the floor. The design of the beam ceiling consists of the beams themselves, the roll, the floor and the insulation.

With a rectangular plan of the house, it is advisable to block the span in the direction along the short wall.

Scheme of laying floor slabs along a short wall

So that the beams do not bend under the weight of the floor, they must be laid at a certain distance (see table). The cross section of the beam is determined based on the load attributable to it.

For example: You need to build a ceiling with a size of 3.0 * 4.0 m. Wooden beams (section 6x20) are laid along a wall equal to 3.0 meters. If the floor is interfloor, the beams are laid at a distance of 1.25 m from each other, if the attic floor is 1.85 m. loads.

The thickness of the floor boards also affects the distance between the beams. If they are 28 mm thick or less, the distance between the beams should not exceed 50 cm.

Advantages of a wooden floor:

• The main advantage is that the wooden floor is quickly and easily mounted in any (even difficult) place, without the use of any special tools, that is, you can do without a crane and other equipment. Wood flooring is light and relatively inexpensive.

Disadvantages of wood flooring:

• The main disadvantage of wooden floors is the increased flammability, sometimes the possibility of decay and infection with bark beetle.

Technology of installation of wooden floors:

Beam installation: Before installing the beam, it must be treated with an antiseptic solution. If the beams are supported by stone or concrete wall, then its ends must be wrapped with two layers of roofing material. The beam is brought into the nest prepared during the construction of the wall. When inserted into the nest, the beam should not reach the back wall by 2-3 cm. The end of the beam is made beveled.

Beam installation scheme

(1 - beam, 2 - roofing material, 3 - insulation, 4 - solution).

Left in the nest free space fill with insulation, you can fill it mounting foam.

Roll setting: Bars (section 4x4 or 5x5), which are called cranial, are nailed to the side faces of the beams.

Scheme of rolling wooden shields

(1 - wooden beam, 2 - cranial bar, 3 - roll-up shield, 4 - vapor barrier, 5 - insulation, 6 - clean floor finish, 7 - ceiling finish).

These bars are attached to the reel of wooden shields. The reel is made from boards from longitudinal boards or boards from transverse boards. The reel plates must be tightly pressed against each other. They are attached to the cranial bar with self-tapping screws. The roll serves as a preparation for attaching a "clean" ceiling.

Insulation pad: An integral part of the wooden beam ceiling is insulation, which in the interfloor ceiling performs, first of all, the role of sound insulation, and in the attic floor also the function of thermal insulation. First of all, you need to decide what material to use. Mineral wool, foam plastic, slag, perlite, expanded clay, as well as dry sand, sawdust, shavings, straw, tree foliage can serve as a material for insulation. Mineral wool - the material is light, easy to use, unlike polystyrene "breathes", has sufficient heat and sound insulation, in general, in most cases, wool is suitable for warming interfloor and attic floors. Expanded clay (fraction 5-10 mm) - the material is heavier mineral wool, which makes the structure heavier (the weight of 1 m2 of expanded clay is from 270-360 kg).

After fixing the roll, a layer of thermal insulation is placed on top of it. First, a layer of roofing paper, glassine or vapor barrier film is laid between the beams, bending it about 5 cm onto the beams and proceed to thermal insulation. The thickness of any insulation for interfloor floors should be at least 100 mm, and for attic floors, that is, between a cold and heated room - 200-250 mm.

Cost and consumption of materials: Timber consumption for traditional wooden floors is approximately 0.1 m3 per 1 m2 of floor at a depth of 400 cm. And the cost of the boards will cost you about $ 200 per cubic meter. The cost per 1 square meter of flooring on wooden beams is from $ 70 and more.

Ceilings on metal beams

Compared to wooden ones, they are quite reliable and more durable, and also have a smaller thickness (save space), but such floors are rarely erected. To fill the openings between the beams, you can use lightweight concrete inserts, lightweight reinforced concrete slabs, wooden shields or wooden deck. The mass of 1 m2 of such an overlap often exceeds 400 kg.

Advantages:

• A metal beam can cover large spans (4-6 meters or more).

• The metal beam is non-combustible and resistant to biological influences (rot, etc.).

But overlappings on metal beams are not without drawbacks:

• in places of high humidity, corrosion forms on the metal.

• In addition, such ceilings have reduced heat and sound insulation qualities. To mitigate this shortcoming, the ends of the metal beams are wrapped with felt. In such ceilings, the supporting element is a rolled profile: I-beam, channel, corners.

Rolled profile

Prefabricated reinforced concrete hollow slabs 9 cm thick are laid between the beams. A layer of slag and reinforced concrete screed 8-10 cm thick is applied over the reinforced concrete slabs. Steel consumption is high - 25-30 kg / m2, depending on the steel grade from which the beams are made.

Scheme of the design of a precast concrete floor slab on metal beams

1 - "clean" floor; 2 - boardwalk; 3 - beam; 4 - prefabricated reinforced concrete slab; 5 - waterproofing; 6 - plaster mesh; 7 - plaster.

Material cost: Price steel profile ranges from 7 to 18 USD/rm. The cost of lightweight reinforced concrete slabs - from $ 110 per piece. For 1 square meter of flooring on metal beams, you will spend from $ 100 and more.

Ceilings from reinforced concrete beams

Arranged on spans from 3 m to 7.5 meters. The work is complicated by the need to use lifting equipment. The weight of such beams is 175 - 400 kg.

Advantages:

• With the help of reinforced concrete beams, it is possible to cover larger spans than with the use of wooden ones.

Flaws:

• For installation of ceilings on reinforced concrete beams, it is necessary to use lifting equipment.

Installation: Reinforced concrete beams are laid at a distance of 600-1000 mm. The filling of the inter-beam space is arranged in the form of lightweight concrete slabs or hollow lightweight concrete blocks (with plank or parquet floors, slabs are used, and with linoleum or parquet floors on a concrete base, hollow blocks are used).

Scheme of the design of a floor slab from a lightweight concrete slab on reinforced concrete beams

(1 - reinforced concrete beam, 2 - light concrete slab, 3 - cement screed and substrate, 4 - parquet, laminate)

Scheme of the design of a floor slab from hollow blocks on reinforced concrete beams

(1 - reinforced concrete beam, 2 - hollow blocks, 3 - cement screed, 4 - linoleum)

The seams between the beams and slabs are filled with cement mortar and rubbed. Attic floors they must be insulated, interfloor soundproofing, basement ceilings are also insulated.

Floor slabs from hollow blocks on reinforced concrete beams

Cost: For one linear meter of a beam, you will have to pay from $ 25. The price for one lightweight concrete block is from $1.5. As a result, you will spend from 65 dollars per 1 square meter of reinforced concrete beams.

Beamless floors

They are homogeneous elements (slabs or panels) laid close to each other or a solid monolithic slab, which simultaneously serve as load-bearing and enclosing structures. Depending on the implementation technology, beamless ceilings can be prefabricated, monolithic or precast-monolithic.

Precast concrete floors

The most popular, especially in brick houses. For the installation of reinforced concrete floors, two types of panels are used: solid (they are produced mainly from lightweight concrete) and multi-hollow. The latter have round holes, a kind of "stiffening ribs". Panels are selected depending on the width of the overlapped span and bearing capacity.

Advantages:

• Reinforced concrete slabs have high strength and are designed for a payload of over 200 kg/m2.

• Unlike wood, concrete is not afraid of moisture and does not require any maintenance.

Flaws:

• When installing the ceiling of reinforced concrete slabs, lifting equipment is required.

• It is not always possible to buy ready-made plates of the right size, since they are made in standard sizes at the factory.

Beamless floor scheme for the house

Installation: Floor slabs are laid on a layer cement mortar grade 100. The support of the plates on the walls (wall more than 250 mm thick) must be at least 100 mm. The seams between the slabs must be cleaned of debris and carefully filled with cement mortar.

Approximate cost of the material: The cost of one floor slab is from $110. For 1 square meter of reinforced concrete slabs, you will spend at least 35-40 dollars.

Monolithic reinforced concrete floors

Can be various shapes. Monolithic reinforced concrete floors are a solid monolithic slab 8-12 cm thick made of concrete grade 200, based on load-bearing walls. The weight of a square meter of a monolithic ceiling with a thickness of 200 mm is 480-500 kg.

Photo of reinforcement of a monolithic reinforced concrete floor

Installation of monolithic ceilings is carried out in four stages:

• Installation of steel load-bearing beams in prepared places;
• Installation of suspended wooden formwork from unedged boards (suspended from steel beams);

Hanging wooden formwork from unedged boards

• At laying reinforcement (diameter 6-12 mm);
• Concreting of the floor slab with M200 concrete.

Advantages of a monolith:

• Absence of expensive loading and unloading operations and higher quality of the concrete surface that does not require grouting, as well as the possibility of implementing complex architectural and planning solutions.

The disadvantages of monolithic floors include the need to install wooden formwork over almost the entire area of ​​\u200b\u200bthe future floor. However, this does not mean that the formwork must be set all at once. Overlapping can be done in separate spans, transferring the formwork as the concrete sets.

Installation: Before proceeding with the installation of the ceiling, it is necessary to build a formwork (it is bought ready-made or rented), which consists of telescopic racks, tripods, uniforks, beams, flooring and plywood. Formwork made of wooden and aluminum beams allows for the formwork of ceilings of any configuration - rectangular, cantilevered and even round. Sheets of plywood are superimposed on the upper wooden part of the beam, forming a formwork for pouring concrete. Next, install and fasten the reinforcing cage. The ends of steel rods 60-80 cm long are bent and tied with wire with reinforcement. Then, over the entire floor area, concreting is carried out to a height of 10-30 cm. Complete adhesion of concrete occurs after 28 days.

Formwork for a monolithic floor slab made of wooden flooring and plywood

Installation of a reinforcing cage in the formwork for the installation of a monolithic reinforced concrete slab

Approximate material cost: The cost of slab formwork, with wooden and aluminum beams, is from $40. The approximate consumption of reinforcement per floor is 75-100 kg / m3 of concrete. The cost of 1 ton of rebar is $650. The cost of 1 cubic meter of finished concrete is from $130. As a result, the price for 1 square meter of a monolithic floor will cost you from $ 45 and more (excluding the cost of formwork).

Prefabricated monolithic ceiling

A more modern solution for the installation of floors. The bottom line is that the space between the floor beams is filled with hollow blocks, after which the entire structure is poured from above with a layer of concrete.

Prefabricated monolithic ceiling for the house

Advantages:

• Mounting without application lifting mechanisms, improvement of heat-insulating properties, the possibility of arranging complex-shaped ceilings, reducing construction time.

Flaws:

• The disadvantages are that prefabricated monolithic construction has a labor-intensive (manual) laying process, which is not advisable when building a house of 2-3 floors.

Installation: During installation, the beams of the prefabricated monolithic floor are laid on the walls with a step of 600 mm. Weight running meter beams do not exceed 19 kg. This allows, in most cases, the installation of beams without the use of a crane. Hollow blocks are manually laid on the beams. Weight expanded clay concrete block- 14 kg, polystyrene concrete - 5.5 kg. As a result, the own weight of one square meter of the original floor structures is 140 kg for expanded clay concrete blocks and 80 kg for polystyrene concrete blocks.

The floor structure prepared in this way performs the function of a fixed formwork, on which a layer of monolithic concrete of class B15 (M200) is laid.

Before pouring concrete, it is necessary to reinforce the structure with a reinforcing mesh with cells measuring 100x100 mm from wire with a diameter of 5-6 mm.

The weight of one square meter of finished flooring is 370-390 kg for expanded clay concrete blocks and 290-300 kg for polystyrene concrete blocks.

Expanded clay concrete block for prefabricated monolithic floor

Approximate cost: The cost of prefabricated-monolithic floor structures (beams and blocks) will cost you 40-50 dollars / m2. The cost of structures of the finished floor (beams + blocks + mesh + concrete) - 70-75 dollars / m2.

Heat and sound insulation of floors:

The thermal protection of the ceiling must be such that the temperature on the floor surface is close to the temperature of the indoor air and does not fall below it by more than 2 ° C. To avoid dampness between heated and unheated rooms, to protect the insulation layer from moisture, a layer of glassine should be placed above the thermal insulation.

Scheme of laying heat and sound insulating materials in the ceiling

(1 - wooden beam, 2 - cranial bar, 3 - rolling, 4 - insulation layer, 5 - vapor barrier film or glassine, 6 - boards)

In addition to good thermal protection, ceilings must also provide sufficient sound insulation of the premises. In accordance with current regulations (RF data), the insulation index Rw must be equal to or greater than 49 dB.

For hollow core reinforced concrete slabs with a thickness of 220 mm, the insulation index is Rw = 52 dB.

For wooden floors (insulation layer 280 mm + one layer of drywall 12 mm), the sound insulation index is 47 dB.

Now a little about heaters. Ready-made mineral wool slabs proved to be good as thermal insulation. In addition to the well-known insulation with ready-made mineral wool slabs, there are alternative options that are performed on site. For example: It is possible to pour slag or ordinary sawdust on a roofing material lined with roofing material or covered with a clay solution with the addition of sand (the solution must dry well). By the way, they are 4 times lighter than slag and at the same time provide 3 times better thermal insulation with the same layer thickness. So, at a winter temperature of -20 ° C, the backfill from slag should be 16 cm thick, shavings - 7, and from sawdust - only 5 cm.

Sawdust concrete slabs for the same purpose can be made independently. To do this, you can take 1 volume part of sawdust, 1.5 parts of lime mortar or 4 parts of clay, 0.3 parts of cement and 2 to 2.5 parts of water. The finished slabs are dried in the shade, laid on a roofing material, the seams are sealed with clay or lime mortar. Square meter such a plate weighs about 5-6 kg with a thickness of 10 cm.

What flooring to choose for your home. It all depends on the type of house, as well as on the installation technology and the price of this floor. As a conclusion to this article, I will give a table in which you can compare different types overlays and choose the most suitable for yourself.

Attention: In this article the prices are presented for the period of 2008. Be careful!

reinforced concrete slabs, monolithic ones are also popular among private developers. Their advantages include not only the solidity and durability inherent in the same plates, but also the ability to cover rooms of any configuration. At the same time, the disadvantages include a large mass of plates, requiring a reinforced base and wall materials of increased strength, and the need to assemble the formwork. Therefore, many self-builders, including the craftsmen of our portal, prefer a lightweight variety - monolithic ceilings on a profiled sheet, which will be discussed in the material. Consider:

• What is a monolithic overlap on a profiled sheet.
• Technology of the device of steel-reinforced concrete floors.
• The experience of the portal participants in the installation of unsupported monolithic ceilings according to the profiled sheet.

Monolithic overlap on a profiled sheet

Initially, NIIZhB (Research Institute of Concrete and Reinforced Concrete) of the USSR State Construction Committee developed a method for pouring monolithic reinforced concrete floors with steel (SPN) for industrial buildings and structures. The first recommendations for the design of monolithic reinforced concrete floors with SPN were developed in 1987, after almost two decades, STO 0047-2005 appeared, in fact, slightly updated version first option. However, for those who want to understand the technology and make calculations on their own, without resorting to the services of a pro, our old-timers are advised to first study the training manual from the Land of the Soviets.

Yury

If you want to understand without extra costs, read the recommendations for the design of monolithic reinforced concrete floors with steel profiled decking, NIIZhB, 1987.

The essence of the technique lies in the fact that the corrugated board serves both as an external reinforcement of the plate, as well as the finishing layer.

When talking about industrial premises, such exterior finish more than enough. According to the developers of the service station, lightweight ceilings along the profile, compared to a conventional monolithic slab, have a number of advantages:

• Reducing the amount of steel on beams - by 15%.
• Reducing labor costs - by 25-40%.
• Reducing the mass of the plate - by 30-50%.
• Increasing the rigidity of floors (to horizontal loads).
• Simplification of communications wiring - placement of highways in corrugations.
• The absence of wooden formwork - an increase in the speed of work.

The use of steel-reinforced concrete floors in the construction of industrial and private buildings is permissible under the following basic conditions:

• slightly aggressive and non-aggressive operating environment;
• humidity conditions up to 75%;
• the temperature in the room is not higher than + 30⁰С;
• used concrete without potassium chloride and other chlorine-containing additives.

That is, the main contraindication to this type of flooring is high humidity, which is why they are usually used as interfloor and are not used between the basement and the first floor or the basement and the first floor.

al185 FORUMHOUSE Super Moderator

The profiled sheet in the base will rot, who are interested in the timing, look with a search. On the protection of the wheel arches, galvanized self-tapping screws rust in a couple of months.

For pouring slabs, it is allowed to use both heavy and light concretes, but the compressive strength class for heavy concrete on fine-grained aggregates is from B15 (M200), for lightweight concrete on porous aggregates - from B12.5 (M150). The minimum layer of concrete above the profile flooring is 30 mm, if a finishing screed is provided, if without a screed - from 50 mm. The flooring is made of load-bearing profiled sheets (H), with a corrugation height of 44 mm.

For the reinforcing cage, reinforcing bars of a periodic profile, class A-III, and class Bp wire are used. If it is planned to overlap with a stairwell, then it is necessary to reinforce the reinforcing cage around the perimeter and install side formwork. Steel beams of the load-bearing frame are either rolled or composite profiles.

Technology for the installation of steel-reinforced concrete floors

In the original version, the profiled sheet is laid not only on the walls, but also on the frame of steel beams (girders), which is the carrier. The number and parameters of the beams are calculated individually, based on the dimensions of the overlapped span and the expected loads, the average step is from 1.5 to 3 m, but each sheet should have three support points - in the center and along the edges. Single-layer reinforcement - mesh, wire diameter from 3 mm, pitch 200 × 200 mm, thickness of the protective layer over the mesh is at least 15 mm.

Profiled sheets are laid across the long side of the span, with wide corrugations down, along the length on the overlap runs, at least one wave, butt-to-width. Between themselves, the waves are fixed with rivets or self-tapping screws with a step of no more than 500 mm. In order for the profile and runs to work as one system, the flooring is fixed with rod anchors that are welded to the beams. Next to the load-bearing walls, the anchor must pass through each wave, on intermediate beams through one. In addition, the flooring is fixed to the beams by means of self-tapping screws or dowels.

However, the use of steel beams is not the most attractive option for self-builders, so many of the craftsmen of our portal prefer Alternative option- unsupported monolithic overlap along the profile sheet.

The experience of the portal participants in the installation of unsupported monolithic ceilings according to the profiled sheet

winder

Overlapping along a profiled sheet can be without I-beams or channels.

Instead of a frame, a bearing profiled sheet is used with a wave height of 60 mm or more, a thickness of 0.7 mm, and reinforced reinforcement - lower, upper, transverse and mesh. In this case, the profiled sheet is fixed formwork, and the main load is taken by the reinforced reinforcing cage. The sheets are laid with a narrow corrugation down and, just as in the method with beams, they are oriented in waves across the long side of the span. It turns out a kind of ribbed monolithic overlap, only the ribs are formed not by removable formwork, but by corrugations. Unlike a steel-reinforced concrete slab supported by beams, this slab is not recommended to be poured with lightweight concrete, and the compressive strength class should be increased to B22.5 (M300).

winder

It is reinforced concrete that holds the load, neither foam concrete nor expanded clay concrete have the necessary strength. Strengthening the reinforcement in this case is useless.

When pouring, be sure to carefully vibrate the solution. If necessary, props are placed from below, which are removed after the concrete has gained strength.

One of our craftsmen decided to use the profiled sheet not only as a formwork, but also as an additional power frame.

worodew

I make a monolithic ceiling according to the H75 profiled sheet, 0.7 mm thick. In order not to lose its bearing capacity, after pouring, I decided to include it in joint work with concrete. I did this: with a puncher (drill 6 mm) in each ridge I punched holes every meter and inserted pieces of wire 6 mm thick, 10 mm long into them, and instead of stars I put and tied reinforcement on it, plus a mesh on top. Even stiffness has increased, I compare before and after knitting reinforcement.

Spans of 3.6 and 2.0 m, in a wave reinforcement 12 mm, on top - a wire mesh 5 mm thick, with a cell of 100 × 100 mm. From below, he closed the waves with cut-off gas block and sealed the slots with mounting foam, one cylinder was enough for 70 m². The flooring rests only on the outer walls and on bearing wall in the middle. The slab was poured with a concrete pump, the ceiling thickness was 130 mm, the area was 76 m², about 7 m³ of mortar (M300) was taken. After a few hours, it was possible to cut off the bumps, focusing on the rule, the next day I moistened the slab and polished it.

The underfloor heating system is usually mounted in a finishing screed, but if desired, you can combine a warm floor and a monolithic ceiling along a profiled sheet.

Toha71

Is it possible to install TP pipes directly into the poured slab? Will the presence of TP pipes in it not weaken such an overlap? And if possible, how much thickness to add under the 20 pipe? As I understand it, the TP must be placed between the layers of reinforcement so that the top layer of reinforcement in concrete is not “drowned” for its normal operation? I would like to try once and pour the concrete evenly so that only the finishing self-leveling floor remains and you do not have to load the slab with an additional screed.

The method has the right to life, subject to an increase in the thickness of the overlap and the presence of certain experience.