Do-it-yourself interfloor overlapping is important to install correctly, gradually applying construction technology. It is necessary to delve into all the details of the construction of buildings.

At the first stage, it is important to determine the thickness of the main load-bearing walls of the first and second floors; the thickness of the future floor will depend on this. According to the standard for houses made of brick or aerated concrete, the interfloor ceiling can be installed from 15 to 20 cm, in houses made of more brittle materials thickness decreases. Technology floors depends on the selected materials, the height of the future structure and the weight of the entire structure.

Formwork and formwork installation

start with the formation of formwork. It is installed between floors, designed for stable fastening of the transverse beams. If there are old wooden planks their use would be appropriate. Initially, having formed a coating of boards, it is necessary to install a support. Often used stable logs. A layer of waterproof plywood is laid over the formed structure. Next, check the quality of the structure for sagging. When eliminating shortcomings and bends, you must immediately eliminate them. In the future, the design must be stable, withstand the additional load of furniture, distributing the load.

The device of interfloor overlapping is divided into several main types:

• Reinforced concrete;
• Monolithic;
• prefabricated;

Do-it-yourself reinforced concrete flooring is popular in stone and brick buildings. A design feature is the laying of hollow panels. When seams are formed, they are completely filled with mortar. The disadvantage of the formation of overlaps reinforced concrete type is the massive weight and the need to use lifting equipment. In addition, the plates have a standard size. With the perimeter of a house different from standard project, it will be difficult to correctly install the support of each plate.

Do-it-yourself wooden interfloor ceiling built if you want to save money and time for construction. At the same time, it is important to correctly determine the type of overlap and the ability to carry out installation without the involvement of additional equipment, renting forklifts and a team of specialists.

Monolithic cover. Main characteristics

The device of interfloor overlapping monolithic type is a homogeneous solid structure, the mass of which is distributed on the load-bearing walls. The application of the monolith is different undeniable dignity in the absence of the need to use construction equipment. This coating is effective in that it makes it possible to implement modern architectural solutions handmade without additional costs. Before starting installation, it is advised to prepare building beams that will serve as a support. The steel surfaces of the beams are mounted on wooden partitions.

Typical formwork includes the presence of elements:

• Special telescopic racks;
• Holding tripods;
• Flooring;
• Main moisture resistant plywood;
• Frame and fittings.

The nuances of laying reinforcement with your own hands

Installation of interfloor ceilings carried out as far as possible without touching the surface of the formwork. The dimensions of the reinforcement range from 6 to 12 mm. At the same time, the structure is fixed with certain clamps. The formed frame leaves cells 10 * 10 cm. A wire is used to tightly bind the frame to the cells. Beams can be applied various types from wood to aluminium. Further, the entire surface of the layer is densely filled with mortar, forming a uniform surface.

It is quite difficult to completely fill the ceiling with your own hands. The main nuance is in the implementation of the casting layer no more than 10-12 hours from the previous one. To create a uniform layer, the solution must not be allowed to dry completely. The technology of interfloor overlappings makes it possible to obtain reliable adhesion of the monolith to the surface of the overlapping and mortar, fastening the entire structure. This way of creating an overlap with your own hands is the most reliable, safe and easy to install. Complete solidification of the entire layer occurs no earlier than 28 days after the last pour. Uneven drying leads to the subsequent destruction of the surface, the formation of chips, cracks and additional dust. If it is necessary to eliminate the resulting defects, it is important to simultaneously fill the entire surface with a small amount of water and leave to dry completely.

Overlappings of prefabricated monolithic type and their differences

The prefabricated-monolithic type of flooring is the most relevant and in demand in the cottage-type construction market. The combination of support beams on one side and hollow blocks on the other has many advantages. The device of beams of interfloor ceilings must be evenly poured with concrete and the interfloor structure is ready. Weight standard design quite low and is no more than 19 kg per square meter. It is somewhat more difficult to make a prefabricated monolithic floor in time, however, it is not required to rent lifting equipment and all stages can be carried out independently. Wire reinforcement of the entire structure is created no more than 6 mm in diameter.

Removal of formwork and installation of interfloor ceilings

When mounting the main floors, the formwork is removed. Removal of the side surfaces is permitted when the main floor is completely frozen and has formed a solid structure. It is necessary to carefully check the entire surface from all sides.

Strength concrete structure determined by indicators:

• Bearing elements whose span is less than 2 meters make up 50%.
• Slabs with a span of 6 meters or more - 70%.
• Reinforced types of structures no more than 25%.

How to determine the strength of the hardened concrete of the installed floor slab?

The concrete surface increases the strength of the coating from the moment the last layer is poured over time:

• Day 3 strength is about 30%.
• Day 7 increases to 60%.
• Day 14 is 80% or more.
• Day 28 is about 100%.
• The 90th day is increased by 30%.

The curing time of the concrete floor depends on the air temperature and humidity level. environment. There are special additives that help speed up the process of hardening of concrete on the floor surface.

Installation of interfloor ceilings can be time-consuming, in case of difficulties, InnovaStroy specialists recommend contacting experienced craftsmen.

Do-it-yourself wooden interfloor ceiling

Wooden ceiling structure responsible for building sustainable floor covering the top floor and a smooth, reliable ceiling ground floor. The main mass is taken by the bearing walls of the building. The device of wooden floors is the most popular and in demand in modern construction country houses. Due to the ease of construction, the quality of the resulting floor, environmentally friendly materials and economical costs. wooden bars tightly connect the elements of the structure, horizontally carrying out the load on all the main supporting walls.

Benefits of installing wooden floors

• Increased level of thermal insulation;
• Preservation of the acoustic properties of the room (if necessary);
• Simplicity and ease of installation with your own hands;
• Carrying out work in all weather conditions;
• Use of any type of overlap: basement, interfloor, attic, attic.

When using wooden floors in areas prone to moisture accumulation (bathroom, basement, pool area, baths, etc.), it is recommended to use an additional level of waterproofing material.

General characteristics and arrangement of wooden floors

The device of interfloor overlapping on wooden beams requires attention to the possibility of bearing weight. Own weight wood flooring is about 250 kg, while the weight of the additional load is taken into account at least 200 kg.

When choosing the dimensions of the beams, it is necessary to clearly determine:

• The thickness of the beam (according to the standard, at least 5 cm);
• Height 15 cm or more;
• When laying wooden beams with a step of 50 meters or more, it is necessary to use a mineral-type insulating material.

The list of necessary tools for the installation of ceilings with your own hands:

• Availability anchor bolts;
• Keys;
• Staples;
• Hammer;
• Screwdriver;
• Keys;
• Strong rope;
• Nails;
• Hacksaw for wood;
• Roulette;
• Axe;
• Rigid construction cord.

Owning the stages of technology, essential tool installation of interfloor overlapping is carried out quite easily. Installation wooden floors starts with laying the beam. Professionals advise using a glued look with a length of 12 meters or more.

Differences of a wooden ceiling:

• Used when creating individual design of cottages .
• The cross section of the material used depends on the width of the opening and the weight of the future structure, the ability to hold the load of the building foundation.
• When purchasing material for the formation of interfloor ceilings, it is important to pay attention to the quality of the timber. Additional drying for more than 4 months and antiseptic treatment will keep the original quality for a long time.
• In the event of suppuration of wood, the formation of chips and cracks, it is forbidden to use timber!
• All dimensions must be checked and adjusted to the required. The use of beams and bars of various levels is not recommended.
• Fire safety wood flooring required additional processing to form a sustainable impact of open fire.

Sometimes masters recommend using rough bars, which are installed on the edges of the beam elements. Next, a roll is formed and a dense rough coating is formed. Arrangement of ventilation also plays a significant role in creating a cozy interfloor overlap. free circulation air currents between floors allows you to maintain a comfortable climate inside the building.

The InnovaStroy company specializes in the construction of houses according to individual orders"Full construction". High-quality interfloor ceilings are the main task of creating comfortable multi-level housing.

Video existing species do-it-yourself interfloor ceilings, offered for viewing by InnovaStroy.

It was in October, it was constantly raining, such weather will give the best hydration of concrete, the main thing is not to pour concrete in the rain itself.

The budget was approaching zero, or rather, it was almost non-existent, we had to borrow funds, in order to save on reinforcement, a mesh of 14 reinforcement was used 1 layer instead of two, but we additionally reinforced the frame with crossbars for rigidity.

First of all, crossbars were knitted.

For the convenience and speed of knitting the crossbars, 4 fittings were hammered into the wall of the house.

In advance, a part of the reinforcement was released from the concrete belt to connect it with the floor reinforcement.

In places interior walls, belts and additional reinforcement were not made.

Before attaching the boards, a frame was made, logs with supports from a bar of 150 × 50 mm.

(loadposition adsense)

First of all, you need to beat off the level in each room and nail a beam of 50 × 50 mm perpendicularly under the lags along it. Nails 100-150 mm. We nailed straight to concrete belt while it was damp, the nails entered it well. Additionally, planks were nailed under the 50th. with a bar about a meter apart with a consumption of about 6 nails per plank, since the walls are made of shell rock and the nails in it do not hold very tightly, it all depends on the density of the stone.

The supports were also fixed by nailing 2 nails obliquely to the lags.

At the bottom, they also made soles for props and fixed them with nails, as they would easily drown in the damp screenings covered with cheese.

When the formwork was completed, they started knitting the frame, the frame was made of the 14th reinforcement, the cells were 20 × 20 cm. Before the frame was knitted, the film was laid out on a wooden floor.

On top of the finished mesh of reinforcement, a crossbar was tied every meter.

The height and width of the crossbar is 10 cm.

We left a place for the future hatch to the second floor, the size was random, 1000 × 2000 mm.

That's all monolithic concrete floor ready. The ceiling was poured in 3 days, the volume of concrete was 14 cubic meters, approximately 800 kg of reinforcement. The concrete was kneaded by hand in a trough with a volume of 0.4 cubic meters. You can walk on a fresh floor the very next day, but in no case do not load it with materials until it is completely hardened, microcracks may form. The formwork was demolished in April.

5 Comments

Hello Eugene! Thank you for noticing my pipes! The ceiling dimensions are 8.600x9.200 m, the thickness of the ceiling is 200 mm, the longest span is 6 meters. If you are interested in any other details, I will be happy to answer.

Hello Vitaly! I was pleasantly surprised by your promptness. Looking through the photos of the overlap and explanations for them, I realized that despite any difficulties, you are optimistic about the future.
And I'm happy for you. I am building a house on my site and this month it is necessary to fill in the ceiling - 125 sq.m. I need 17.6 cubic meters of concrete. Now we are laying the frames of the beams, the reinforcement of the mono-belt, and then the reinforcing mesh of the plates, but the thickness of the plate is 8 cm, and the beams are 10x25 cm, with a span of 4.4 m, the reinforcement is 8-10 mm. And who prompted you to choose such a type and such dimensions? I think that 8 cubic meters of concrete could be enough for you, and this is a big savings, and the load on the shell rock would decrease by 14.5 tons. But it's done and it's good. And the last question. Will you talk about the new stages of construction? All the best Vitaly.

Hello Eugene!
I confess honestly at the time of construction, no special calculations were made, they did it “like everyone else”. Regarding the overlap, 80% of the overlap area is a span of 6 meters, if you count from the bearing to the bearing wall, I do not take into account the partitions, since I have a soil of chernozem 1-1.5 m and the foundation for the partitions is cast separately with a depth of about 60- 80 cm
Regarding the thickness of the overlap, they usually make a calculation where the span length is divided by 25-32, hence the thickness. With a smaller thickness of the slab, deflections greater than the allowable ones are possible (only from the weight of the slab itself), if the slab is not pre-stressed. The 12.7 cm thick regular heavy concrete slab meets most fire and fire safety regulations.
I will also add that in our area the seismic is 9 points, so I did not spare the material, since in the future I plan to put the house into operation.
Yes, of course, I will publish materials in the "With my own hands" thread, there is a photo, it remains only to prepare the text, but at the moment I'm busy with work (covens), I'm doing interior decoration, closer to the autumn I will take a closer look at the site. I can also publish your works by making a separate section or “blog” for this, I think your experience will definitely be useful to other users of the site.

Hello Vitaly. I'm thinking about solving a similar problem. House 2 fl. Inner size 9x11. The capital wall of 1 brick divides 11 meters into 4.5 and 6.5 meters. Overlapping ceiling after the 2nd floor. I also plan to make concrete from reinforcement in 2 layers, the bottom layer of 14 mm, upper layer 10 mm. Internal walls The rooms in the brick floor have already been driven out. The largest room is 4.2 square. If 4200:32=131 mm is the overlap thickness. Thicker would not want to load the foundation. There are no rails. What can you say about the thickness of the overlap?

Thank you.

Concrete was ordered M300. Supplier - titanbeton. en
Two drivers who visited me do not understand Russian, do not have maps, do not know the area. The first one had to be fished out in a neighboring town, according to his unintelligible tips, something like "I'm standing at the store, I don't remember what I was passing through." Basically, it got on my nerves. They carry 5 m3. Well, if there really was 4.5 m3.

Separately, a few words about the concrete pump. Initial price - 18 tr. Arrow 32m, poured through the fence without any problems without leaving the asphalt. The driver is a good man, although at the end he asked for 2tr more than what was allegedly claimed for the "move", but he explained and told everything about the filling process itself. The unit itself is very difficult to work with. Although the carrier tried to supply concrete intermittently with one “pumping” of the pump, the pressure and flow rate required great efforts to turn the sleeve back and forth, directing everything inside such a narrow formwork, evenly distributing concrete in layers of 30 cm.

In total, 17 cubic meters of concrete were ordered, the possible refusal of the last mixer at RBU was agreed in advance, payment was made on the spot. After pouring 2.5 mixers, that is, 3/4 of the total volume, after thinking and thinking, we decided to hang up on the concrete unit, we were afraid that the formwork would not survive. They began to vibrate in the old fashioned way, with reinforcement bars - for the same reason. As it turned out, not in vain.
The concrete ran out, the last mixer left. In the receiver of the concrete pump, as expected, there are 200-250 liters of concrete left. The carrier said to point the sleeve somewhere in order to swing something else. Throwing your sleeve on thin wall partitions, we did not expect that in a couple of seconds he would spit out another 70-90 liters there almost to the top. And then the formwork cracked ... everyone froze. On M10 studs of medium height, washers with a diameter of 30 mm were pressed 0.5-1 cm on each side into wooden racks and as it turned out, one of the studs broke the nut. Thus, the formwork has become wider by these centimeter and a half. There was no further destruction, I exhaled. Geometry violations are not critical. After removing the formwork, they are not noticeable at all.
The remaining concrete was poured onto the platform next to the gate onto the bedding film. We also dragged this concrete into the formwork in buckets, leveling the level more or less everywhere, just up to the windows. Having done everything once more, they parted on this.

The next couple of days, periodically pouring concrete, on the ground closer to the pit, a formwork was assembled that could accept a 5-cube mixer. According to estimates, a volume of 4.8-4.9 m3 was needed. Having agreed with four working crests nearby, I made an order in TitanBeton. I made several portable ladders around the formwork, through which concrete could be poured immediately from the wheelbarrow. The mixer arrived and unloaded. We started to carry. Two people are constantly raking concrete with shovels, one carries it on a wheelbarrow, two more stand inside and pass buckets to each other. I don't remember exactly how long it took. But the concrete did not have time to rise. 2.5-3 hours, I think we managed. However, the concrete was not enough and well. All vibrated. I drove to the market for cement, leaving myself one assistant, they made about 9 more batches of 400 liters. I ran great. Covered everything with a film, left.

After waiting a few days, I began to slowly disassemble everything. I dismantled the trough for concrete, scaffolding, tore off the film. The weather was rainy, so I was not afraid for the concrete to dry out.

Pouring a monolithic floor slab is not the easiest, but a truly universal and time-tested method. In this article, we will cover the main structural features and stages of flooring, as well as types of formwork, including fixed formwork.

Building typology and scope

The main scope of monolithic floors are buildings with load-bearing walls made of brick, block masonry or concrete panels, as well as domed houses. The requirements for the solidity of the overlap may be due to:

• non-standard building plan;
• the need to significantly increase the bearing capacity of the floor;
• increased requirements for hydro and noise insulation;
• the need to provide free planning;
• reducing the cost of interior decoration.

Filling is carried out, as a rule, after the completion of the construction of the walls of the first floor. However, there are options for pouring monolithic ceilings already in buildings with a roof, if weather or other conditions so require. In this case, I-beams are mounted on the masonry of the lower floor and a crown is poured along the perimeter of the bearing walls to the height of the ceiling. Also, to strengthen mechanical bonds, with inside the crown is released by 40-50 cm of embedded reinforcement. Its total cross section cannot be less than 0.4% of the cross section of the longitudinal section of the crown.

Design calculations of the supporting structure

When choosing the span length, it should be related to the thickness of the slab as 30:1. However, with independent design, there is practically no point in making an overlap thicker than 400 mm, since load bearing capacity structure rises along with its own weight and static stresses. Therefore, the permissible load on self-made ceilings rarely exceeds 1500-2000 kg / m 2.

The situation can be corrected by including in the supporting structure I-beams steel beams laid on a concrete-leveled masonry surface of the bearing walls. Another way to increase the length of the span while maintaining relative freedom of layout is to support the ceiling on columns. With a thickness of a monolithic structure up to 400 mm and a span in four directions from the columns up to 12 meters, the cross-sectional area of ​​​​the support is 1-1.35 m 2, provided that the cross section of the embedded reinforcement in the column is at least 1.4%.

Calculation of reinforcement of a monolithic slab

In general, the thickness of the plate is determined by the amount of reinforcing steel that is embedded in it. Reinforcement density, in turn, depends on the limit permissible load and fracture resistance. Avoiding special cases, one can give general example design that demonstrates full compliance regulatory requirements with a sufficiently high margin of safety.

In private construction, reinforced concrete is reinforced with reinforcement with a periodic profile of class A400, aka A-III.

Diameter of rods in slabs thick:

• up to 150 mm - not less than 10-12 mm;
• from 150 to 250 mm - not less than 12-14 mm;
• from 250 to 400 mm - at least 14-16 mm.

The reinforcement is laid in two meshes with a mesh size of 120-160 mm, the thickness of the concrete protective layer from the edges of the slab is at least 80-120 mm, and at least 40 mm above and below. The direction of laying four rows of reinforcement, starting from the bottom: along, across, across, along. For ligation, galvanized wire with a thickness of at least 2 mm is used.

Installation of formwork of various types

Formwork must withstand a load of 500-1100 kg/m 2 , including the dynamic impact of falling concrete. To create a formwork plane, you can use:

1. Plastic sheets of reusable formwork.
2. Moisture resistant plywood 17-23 mm thick.
3. OSB 20-26 mm thick.

The edges of the slabs should fit snugly against the walls; it is not allowed to use formwork with gaps at the joints of more than 2 mm, unless it is planned to cover the surface with a waterproofing film.

Sometimes it is reasonable to make the formwork permanent, using profiled sheets for this, orienting them with a narrow shelf down. They are placed along the slab so that the waves form numerous stiffeners during pouring. The calculation of the thickness is carried out from the bottom edge, thus saving concrete mix is 20-25%. In this case, the height of the ridge should not exceed a third of the total thickness of the slab. If the formwork is not planned to be removed, self-tapping screws with a rubber washer are screwed into it and tied with a thin wire to the reinforcement.

Formwork installation begins with the placement of racks: these can be either steel telescopic racks with a tripod and a unifork, or wood without defects with a cross section of at least 100 cm 2. Each post must be connected to two adjacent inch board slanted braces. The racks are mounted along the lines of the beams, the distance between which, depending on the thickness of the plate 150-400 mm, is:

• 190-240 cm with plywood thickness up to 20 mm;
• 210-260 cm with plywood thickness from 21 cm.

In this case, the distance between the uprights of one beam, depending on the gap between them, is:

• from 140 to 200 cm with a span of up to 150 cm;
• from 120 to 180 cm with a span of 160-210 cm;
• from 100 to 140 cm with a span of 210-250 cm.

The main beams, as a rule, are made of timber 100x100 mm. On them across with a step of 500-650 cm, secondary beams are laid, which have a cross section of 50% of the main ones. If the formwork is made of profiled sheet, the step of the secondary beams is equal to 3.5 distances between the waves.

Vertical formwork is mounted from retaining panels attached to outer wall building. Often, aerated concrete blocks 80-100 mm thick are laid around the perimeter to hide the floor belt.

Reinforcement and strapping

After the formwork is installed, it is lubricated with an anti-adhesive compound and the laying of the reinforcement begins. On the crowns and supporting ribs, the rods are tied into a square, keeping the minimum allowable protective layer. The main array of overlap is reinforced with mesh. bottom layer stacked on plastic "crackers" that control the preservation of the lower protective layer. The mesh is tied up at the intersection of every third rod.

After tying the lower mesh, intermediate clamps are installed on it after 100 cm in checkerboard pattern. To strengthen the support on the walls, end clamps are mounted. These elements help maintain the design distance between two reinforcement planes.

The mounted upper mesh is connected to the lower connecting brackets. After completion of the installation, the reinforcing structure should be as one piece and easily take the load from people walking on it.

Pouring concrete

Monolithic floors are poured with concrete grade B20-B30, prepared in factory conditions. Filling monolithic floors should be carried out in one stage, so filling the space with small doses is not recommended. If it is impossible to perform the entire amount of work at once, sections of the slab must be cut with a mesh with a cell of 8-10 mm.

The supply of the mixture to the ceiling can be carried out by a concrete pump or a bulk bucket lifted by a crane. After feeding to the top, the mixture is evenly distributed, seated by vibration and left to harden.

Further actions

Concrete gains sufficient strength after 4 weeks, all this time it needs periodic wetting and protection from rain for the first 2 days. After drying, the formwork can be removed and the walls can be erected.

During the construction of houses, garages, cottages, and other structures, there comes a stage when it is necessary to complete the floors. Ceilings can be interfloor, or ceiling, while made of wood, using wooden beams, using concrete slabs or by pouring concrete. Each of these floor installation methods has its own legal right to exist, supported by economic feasibility applications specific option, in each individual case. In this article, we wanted to talk about a specific case, namely the pouring of concrete interfloor (ceiling) floors. Before talking about the methods of installation of these ceilings, we would like to touch on the topic of application and installation of poured concrete ceilings, let's talk about their feasibility and advantages over other similar ceilings.

Advantages of poured concrete slabs (monolithic concrete slabs)

First of all, cast-in-situ concrete floors should be considered as an alternative to slab floors. Wooden floors are too different from concrete-monolithic floors, primarily in price, monolithic ones are much more expensive, secondly, in strength, they are much stronger, thirdly, in terms of durability and other not so significant differences. That is why it is worth comparing, first of all, with slab ceilings. So, in some cases, monolithic (concrete) floors are cheaper, which is indisputable advantage while having similar strength properties. Another important advantage is that jellied monolithic concrete ceilings can be made in any complex shape, almost anywhere, which is sometimes impossible for standard, factory-made concrete products.

An example of the installation of concrete, monolithic floors

Next, we give a specific example of the installation of concrete floors. IN this case, This particular example, possible improvements that could be made to improve the quality of the overlap, we will describe as alternative solutions. So, first of all, it is necessary to build a support for poured concrete mix and formwork.

After that, it is necessary to mount the armature.

It is best to install with a mounting wire and lay two layers of grating.

One reinforcing grid should be at the bottom, the second, laid through the "frogs" should be at the top. Such a monolithic floor will more correctly perceive the bending load, due to the work of the reinforcement in the most stressed places, which will significantly increase the strength of the floor.

Then we start pouring concrete. It is best to buy the planned volume of concrete for this operation in order to carry out the entire pour at one time, since only in this case you can guarantee the equal strength of the entire monolithic floor structure.

Also, do not pour all the concrete in one place to prevent subsidence and collapse of the formwork for the floor. It is best to apply the concrete mixture evenly over the entire area, in extreme cases, quickly distribute it over this area in any alternative way.

The final stage will be the curing of the concrete mixture under certain conditions (temperature and humidity), which will ensure the technological hardening of the mixture and its quality.

So in more detail about the process of solidification of the concrete mixture can be found in the article "How to pour concrete screed gender." After we dismantle the formwork, and our concrete floors are ready for use.

Calculation of the formwork holding monolithic, concrete floors during pouring

Someone with a certain construction can install a concrete floor based on their life experience, or as they say "by eye". We would like to offer you another, albeit not an institute calculation, but which to a high degree will become your successful guarantee of successful work.

Calculation of formwork for this type of overlap should be carried out according to the main three parameters:

1. For longitudinal load on the supports holding the formwork. Initially, it is necessary to calculate the cross section of the supports for the holding formwork.

How to pour the concrete floor between the floors of a private house yourself?

Is this value not so critical? as subsequent parameters, which is why you most likely will not have problems with it. σ = N/F ≤ Rс where σ are internal normal stresses arising in the cross section of the compressible beam, kg/cm2; N - the mass of our formwork and poured mixture, kg; F - area cross section columns cm2; Rc is the design resistance of wood to compression in terms of yield strength, kg/cm2. (For pine, the design resistance is 140 kgf/cm2)

2. For bending supports from the load Also, do not forget the factor that the bending stiffness of the beam changes with its length. So with an increase in the length of the retaining beam, its flexibility also increases, and the rigidity decreases accordingly. In order to take this factor into account, it is necessary to take the cross-sectional area of ​​the beam with a correction factor φ

σ = N/φF ≤ Rc

the coefficient will depend on the ratio of diameter to length, to facilitate calculations, it can be taken from the series below

L/d = 5 10 20 30 40 50
φ = 0.9 0.85 0.5 0.25 0.15 0.08

3. To ensure the integrity of the formwork base The last thing to pay attention to is the strength of the retaining formwork onto which the concrete will be poured. So the formwork must withstand not only the static mass of concrete, but also the dynamic load during its pouring. Also, do not forget about the possible temporary overflow of concrete to a specific local place and the mass of the worker who will distribute the concrete in it. As a result, the permissible thicknesses of plywood formwork, with a margin of 1.5, with a span of not more than 1 m, can be taken from the range below.

Plywood thickness 18 mm 21 mm

The thickness of the poured layer of concrete floor up to 9 cm up to 12 cm

Now you can not only pour the concrete floor, but also pre-calculate the auxiliary technological elements for its installation.

Pour the interfloor ceiling correctly

• Formwork installation
• What are the types of covers?
• How is reinforcement installed?
• When to remove formwork?
• We determine the strength of concrete
• Let's calculate the cost and expenses

It is very important to fill the floor between floors correctly.

After all, it will be a reliable floor of the first floor in your house, and it will also be a durable ceiling for the basement floor that does not sag under any weight. We will consider step by step how you can properly make monolithic ceilings or floors between floors with your own hands and what we need for this.

Structural scheme of prefabricated-monolithic overlap.

Firstly, we will need skillful hands, a beam, concrete, since we are considering the option of overlapping in a private brick or block house, therefore, in order to successfully complete this business with our own hands, it is necessary to delve into all the details, because we are going to do the overlap with our own hands.

To begin with, we need to determine the thickness of the walls, since the thickness of our overlap between floors will depend on this. Usually, for walls in a private house made of bricks or blocks, a ceiling thickness of 15 to 20 cm is used, for thin walls, such a ceiling thickness cannot be used, and it would be better to use a completely different option.

Formwork installation

The next step will be formwork. It is installed between floors and is designed to fasten the beam. When making formwork with your own hands, you can use old boards. Having laid the boards, they must be supported from below with something, for example, logs. This will prevent sagging of this wood floor. On top of the laid boards, you can put plywood (waterproof). Nessesary to use building level to determine surface irregularities, so that our wooden floor turns out to be even and, in cases of sagging, to eliminate this drawback. This method of filling is called beamless.

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What are the types of covers?

Table where you can compare different types overlays and choose the most suitable for yourself.

There are reinforced concrete, monolithic reinforced concrete and prefabricated monolithic floors.

The former are especially popular for overlapping in brick houses. For their installation, solid panels or multi-hollow panels are usually used, which are laid on cement mortar, the seams between the plates are filled with mortar.

The disadvantage of this method is the need to use lifting equipment, standard sizes ready-made slabs are also a disadvantage, as they may not always fit the size of your house. The advantage of this method is the strength reinforced concrete slabs, and the fact that concrete is not afraid of moisture, unlike wooden floors.

Monolithic concrete floors are solid slab, which relies on bearing wall. The advantage of such a monolithic structure is the ability to carry out work without loading and unloading technical work, wherein concrete surface more durable, sealing seams is not required. More this way makes it possible to resort to bold architectural solutions.

For the installation of this ceiling, it is necessary to use steel beams that are installed on a wooden formwork.

Such a formwork includes several constituent elements: a unifork into which the beams are inserted, the beams themselves, telescopic racks that are held with tripods, flooring and plywood. Plywood sheets are laid on the formwork with a wooden floor, which are the basis for further pouring of the concrete floor of the first floor. Next, a frame of reinforcement is installed.

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How is reinforcement installed?

Fire resistance limit 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.

The reinforcement is laid in such a way that it does not come into contact with the formwork surface.

Reinforcement will need 6-12 mm.

How to make reinforced concrete floor yourself?

To do this, use special clamps (chairs). The laid reinforcement frame should be 10x10 cm cells. With the help of a wire, the reinforcement frame is connected with each other with their own hands. In this method of overlapping, you can use not only a wooden overlap, but also aluminum beams. Everything is ready, now it remains to fill the entire floor area with a solution.

The disadvantage of this type of construction is the need to install wooden formwork over the entire area of ​​​​such a ceiling.

Since we are going to pour our prepared surface with our own hands, we may need to crane or a special trolley with an opening bottom. The concrete floor must be poured correctly. After all, it will not be possible to quickly pour it with our own hands, and therefore we need to take into account that the intervals between fillings should be no more than 12 hours so that the solution does not have time to dry, otherwise there will be no monolith, since the solution will not bond with each other.

Complete bonding or adhesion of the solution occurs in about 3 to 4 weeks or 28 days. Uneven drying of the solution leads to cracks. If this happens, it is necessary to pour water on this surface.

Prefabricated-monolithic flooring of the floor is the most modern device floors.

In this type of flooring, the space formed between one beam to another is filled with hollow blocks.

When all spaces are filled with such blocks, it remains only to fill the entire area of ​​\u200b\u200bthis structure with a concrete solution. This type the structure is assembled by hand without the use of lifting equipment, since the weight of 1 meter of the beam is 19 kg. In terms of time and method of laying, this flooring is more labor-intensive than other types of floors. Before pouring this design, it must be reinforced with wire 5-6 mm in diameter.

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When to remove formwork?

Scheme of small-panel collapsible formwork on frames for monolithic ceilings.

After meeting certain requirements, the formwork is removed from concrete monolithic structures. Side formwork elements that are least subjected to the load from the weight of the monolithic structure are allowed if concrete pavement reached its maximum strength. It is worth being more careful when removing the bearing formwork of monolithic concrete structures.

This action must be performed when all the standards for achieving concrete pouring, the so-called design strength: load-bearing elements of a monolithic structure with a span of up to 2 m - 50%; bearing structures beams, girders, arches, crossbars and slabs with a span of 2 to 6 m - not less than 70%; load-bearing structures with a span of 6 m or more - at least 80%; load-bearing structures reinforced with load-bearing frames - not less than 25%.

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We determine the strength of concrete

Concrete gains its strength by 30% approximately on the 3rd day, on the 7th day the concrete strength will be 60%, on the 14th day - about 80% and on the 28th day the concrete strength is considered to be 100%. However, concrete continues to gain its strength even after 28 days. On the 90th day, the strength of concrete increases by another 30-35% from 100% on the 28th day.

The overlap must be rigid, that is, under the action of loads, it must not deflect (allowable from 1/200 for up to 1/250 of the span for interfloor).

The optimum temperature for hardening a concrete monolithic composition is considered to be 20-25 degrees. Optimum humidity is not higher than 90%. Of course, when building a structure with your own hands, it is difficult to make appropriate measurements of the strength of concrete, but we can still focus on weather and accordingly draw certain conclusions about the strength of our design.

For example, on days when the air temperature is 10 degrees, concrete gains strength by 40-50% on the 7th day, if the air temperature is only 5 degrees, then concrete will gain its strength by 30-35%. In hot weather of 30 degrees, the strength of concrete for 3 days will be 45%. At negative temperatures floor pouring concrete mortar do-it-yourself is not recommended, since concrete in such conditions does not gain any strength at all.

There are special additives in the concrete solution for such cases, but we build for ourselves and with our own hands, so it's better to wait. For now, you can only lay beams, make wooden floors between floors, build and install a reinforced frame, but it is better to postpone pouring concrete. But if you poured beams and reinforced frames with concrete mortar with your own hands, and then the air temperature dropped below zero, then do not rush with the decision to dismantle the formwork, wait for spring and warm weather.