How to pour a slab

For staircases of internal communications there is an opening. It can be partially filled with a board for comfortable walking when pouring, leaving a small hatch with a temporary ladder. Using multilayer plywood reduces installation time, but the estimate is doubled.

At the last stage the contours of partitions and walls are placed with paint. This will improve the accuracy of the passage of electricians, other engineering systems.

Install side shields

Flanging overlap is made by hand from a board with a thickness of 4 cm minimum, you can use a board 5 cm, bought at the initial stage. In order to avoid deformations on the external planes of the walls, pieces of timber are mounted, which are the stops for the formwork side shields.

The maximum strength of the interface plates / walls get the following way:

  • the masonry leaves a longitudinal groove in the middle of the wall
  • three rows before the ceiling, reinforcing rods protruding 40–60 cm above the ceiling are laid in the perimeter walls
      How to pour a slab

This reinforcement is later bent, communicating with the bars of the lower, upper grid of the slab. For bending at right angles with the required radius, a tubular hammer is used.

Communications, void formers, electrics

Within each ceiling, communications are carried out that are easier to install before pouring than to hammer a slab with a perforator afterwards. Traditionally, the maximum concentration of engineering systems is observed in the overlap of the basement / basement:

  • exhaust hoods in every room
  • electrician in all rooms
  • sewage for outdoor network
  • cold-water risers
  • boiler chimney
  • technological openings for low voltage systems, gas line

To install them with your own hands, it is best to use socket fittings for internal sewage with plugs. They are mounted in accordance with the marking of the walls, the plugs are fixed with screws from the bottom of the formwork (through), side shields (for ventilation outlets).

Electric cables are marked with electrical tape, tags, and other convenient ways. It is forbidden to lay a corrugation of the cable along the bottom layer of the armored belt under it. This will reduce the protective layer, weaken the slab in this area. Therefore, after reinforcement wiring electrics must be checked.

Structural reinforcement

In 90% of cases, the floor slab is reinforced with two continuous reinforcing meshes, which causes material overspending. The middle part of the slab does not practically work at compression, therefore a discharged grid with large cells can be used here. However, this requires an accurate calculation of the bar pattern in each grid. Mounting technology with their own hands, see below.

Lower belt

The cells are formed during installation, the rods are tied with wire directly at the place of operation. This allows you to provide the same protective layer (usually 4 cm) on all sides. The main requirements are:

  • break-up of joints when extending the bar in adjacent rows from 60 diameters
  • 3 cm high pads with a minimum size of 10 x 10 cm (concrete, polymer)
  • bend down at right angles along the perimeter for a bundle with walls
  • binding of bent rods protruding from the walls

It is forbidden to put crushed stone, pieces of pipes, fittings, wooden bars under the grid.

Upper belt

Clamps, manufactured independently, are cheaper, taking into account the dimensions of the plate, the specific operating conditions. They are bent with the same fixture that was used to bend the bars in the walls.

Upper mesh knits from rods, laid on the tables. In the middle part of the cell is allowed to increase according to the calculations. The angles of technological openings for internal stairs increase diagonally. In the formwork openings release the rods of the lower grid.

Seam Jumpers

Filling in one go is extremely inconvenient in the absence of external scaffolding around the entire perimeter of the building. Therefore, more often the overlap is made in stages. Vertical lintels are mounted in the following way:

  • cuts at the bottom for first belt reinforcement
  • cuts at the top for second belt reinforcement
  • installation of the shield in place with the installation of reinforcement in the slot
  • foaming of slots in the slots for rods
  • escapes from the flooring through 60 cm

To ensure the connection of two floor slabs, poured in stages, it is possible to make a cut in the first plate. To do this, it is sufficient to fix the longitudinal plank inside the lintel in its middle part between the reinforcement belts, without relying on the lower rods.

Fill the first section

Concrete is ordered from the manufacturer or is made in the building spot. It must be fed, stacked, sealed with a deep vibrator with interruptions not exceeding 2 hours. After this period in the concrete begins hydration, it loses its mobility, does not form a monolith with a previously laid layer.

The dismantling of the technological weld septum is possible on the 4th – 7th day after pouring. The shield can be transferred to the next section to continue work on the same day.

Middle plate

Fill subsequent overlap sections in the same way as the above method. When vibrocompaction should focus on the cessation of bubbles, the appearance of cement jelly, conceal the liquid solution of large gravel. All these factors indicate a normal seal, you can move the tip of the vibrator to the next place.

The area with a staircase is usually filled in last, when you can walk around the rest of the surface with buckets, a leveling tool. The seams are processed after 70% of curing (in the summer on the fourth day). For alignment of the plane, grinding of possible flows, the angle grinder with diamond equipment of the plate type is used. Stripping is possible in a week or two depending on the weather. The first three days the concrete needs moistening without pressure.

The given step-by-step instruction guarantees the greatest possible operational resource. The quality of floors is almost identical to the factory plates. The increase in thickness is due to the inability to prestress the armored belt at home. On the other hand, communications are laid in reinforced concrete at operational sites, which dramatically reduces labor costs, the budget for finishing works.

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Monolithic ceiling do it yourself

The construction of the house and a number of other buildings implies a mandatory arrangement of interfloor or attic floors. Often wood is used to accomplish this task. Wooden floors are easy to install, but if you need to provide high-quality insulation and sound insulation of the room, give preference to concrete floors. Monolithic ceiling of concrete can be made independently. Study the instructions and proceed.

Monolithic ceiling of concrete can be made independently

Content step by step instructions:

Ceiling laying rules

Before starting to perform any work, it will be useful to familiarize yourself with the rules for laying monolithic slabs. The main recommendations are as follows:

  • the length of the span can be no more than 900 cm. This is the maximum allowable length of one monolithic plate;
  • for lifting plates, you must use special equipment. In accordance with this requirement, hinges should be installed in the slab, catching which the crane can lift the product to the desired height. Actually for those situations when the plates are bought in finished form or are made independently, but on the ground;
  • plates can be laid exclusively on pre-aligned walls. There should be no significant distortions and differences;
  • from each edge of the plate should be based on the wall at 9-15 cm;
  • The plates are stacked with the obligatory sealing of technological joints and, in general, all the cracks with the help of mortar. “Dry” styling is not allowed;
  • in the process of mounting the plates, it is necessary to constantly monitor the flatness of their installation. Plumb level and level are used for testing;
  • plates can be laid exclusively on the bearing walls. All kinds of piers are erected strictly after the completion of the ceiling;

    In the process of mounting plates, you must constantly monitor the flatness of their installation.

  • if in a monolithic slab you need to make a hatch, it is allowed to cut it exclusively at the junction of two concrete slabs. Arrangement of the hatch in one w / w product is unacceptable;
  • Contribute a better translation

  • the plates are stacked with a 2-3 cm gap.

    Plates are stacked with a 2-3 centimeter gap

    If the length of one plate is not enough to cover the entire span, you can use one of the two available options:

    • Lay the plates close, leaving gaps along the edges of the room. At the end, the gaps will need to be filled with concrete blocks;
    • Lay the plates not close, but with even intervals (20-30 mm). At the end, fill the gaps with concrete, pre-fixing the formwork under the ceiling so that the mortar does not fall down.

    Installation of formwork

    The technology of arrangement of overlap involves the mandatory use of horizontal formwork. You can rent a finished formwork from a specialized company or you can assemble the necessary construction yourself.

    The first option is more simple and convenient. Finished factory formwork comes with telescopic supports, which allows you to save time on the manufacture of props.

    The second option is more budget. For self-assembly of formwork, use a cut board with a minimum thickness of 2.5-3.5 cm. You can use moisture-resistant plywood with a thickness of 2 cm.

    Boards should be knocked down as closely as possible. If there are noticeable gaps between the boards, the formwork is necessarily lined with a waterproofing film.

    Formwork installation kit

    Prepare the following formwork fixtures:

    Formwork installation

    First step. Install vertical support legs. The best option – adjustable telescopic racks made of metal. In their absence, suitable and wooden logs with a diameter of 80 mm.

    Racks set with meter steps. The distance between the walls and the racks nearest to them should be at least 200 mm.

    The second step. Lay the crossbars on top of the support legs. This is a longitudinal beam, due to which the whole structure placed above will be supported.

    The third step. Place the formwork over the crossbars. First lay the transverse wooden beams on the longitudinal bars, on them – boards or plywood.

    Select the dimensions of the formwork so that its extreme edges abut against the walls without creating cracks.

    Construction formwork monolithic floors

    Fourth step. The upper edge of the formwork should be strictly at the same level with the upper edge of the lined wall. To meet this requirement, adjust the height of the support legs.

    Fifth step. Install vertical construction elements. Due to the fact that the edges of the slab should go on the wall, place a vertical fence at an appropriate distance from the inner edges of the walls.

    Sixth step. Check the flatness of formwork installation with a level. Correct the deviations if they are detected.

    To connect the formwork elements use convenient fasteners, for example, pins or nails.

    For the convenience of subsequent work, the formwork can be covered with waterproofing material.

    Telescopic racks are preferable to their wooden counterparts because metal is much more reliable than wood. Each telescopic stand is capable of withstanding loads of up to 2000 kg without the appearance of deformations and cracks, as can happen in the case of a wooden bar.

    Video – Installation of floor formwork

    Reinforcement order

    Monolithic slab is subject to mandatory reinforcement.

    Floor plate reinforcement

    First step. Prepare the armature. The appropriate diameter of the bars should be selected in accordance with the design loads. In most cases, rods with a diameter of 1.2-1.4 cm are used.

    The second step. Lay the first reinforcing mesh at the bottom of the future monolithic slab. First lay the longitudinal and then the transverse rods. The optimal cell size of such a grid is 120-150 mm. If the overlap has a small area, you can increase the cell size to 200 mm.

    The third step. Tie the bar joints with steel wire.

    Fourth step. Lay on top of the second reinforcing mesh similar to the first. Tie both nets with wire.

    If the length of one rod is not enough, tie an additional rod with an overlap equal to not less than 40 diameters of reinforcement. That is, if you use rods with a diameter of 12 mm, the overlap should be at least 480 mm.

    Bar joints are recommended to be placed in chess. The ends of the reinforcing rods must lie on the supporting beams.

    Concrete preparation

    A standard concrete mortar is prepared for the initial cast. The recipe is as follows:

    • 2 pieces of sifted clean sand;
    • 1 part of coarse aggregate – can use both gravel and gravel;
    • 1 part of cement M400-M500;
    • water.

    Water add so much that the consistency of the solution was close to the consistency of liquid sour cream. Sparse solution perfectly fills all internal cavities and cracks, so that the plate will become truly monolithic.

    The solution is most conveniently prepared in a concrete mixer. First load the dry and hard ingredients, and then gradually, if possible without ceasing to stir, add water.

    In the absence of a concrete mixer, you can prepare a solution in a large trough, but this is too long and rather difficult, especially in the absence of assistants.

    Slab pouring

    The process of casting monolithic overlap can be divided into 2 stages: spilling and finishing fill.


    At this stage, the initial layer of concrete is poured. Pour the solution slowly and measuredly, sudden movements are unacceptable, because the formwork can be twisted because of this.

    Casting monolithic overlap

    Do not spill too thick. The main task of this layer is to fill all available cavities.

    Ready casting “iron” the shovel over the entire surface. Do it smoothly and carefully. So you remove excess air and finally fill even the smallest cavities.

    Monolithic slab thickness

    Finish fill

    At this stage you need to prepare a separate solution. The recipe is the same as in the previous case. The only difference is that you need to take less water to make the concrete more thick.

    First step. Fill the concrete layer with such thickness that it remains about 20-30 mm to the calculated thickness of the finished monolithic slab. Pour slowly and evenly.

    The second step. Smooth out with a shovel like in the previous part of the manual. Leave the concrete for a couple of days and proceed to the next stage.

    The third step. Prepare a solution of 1 part cement and 3 parts sand. Large aggregate is not needed at this stage. Add water to obtain a solution of medium thickness.

    Fourth step. Fill the stove with the solution prepared in the previous step. In the process of pouring, level the slab with a rule until a perfectly smooth surface is obtained.

    At this fill monolithic overlap completed. You will only have some time to monitor the state of the pouring, so that the concrete will freeze and gain strength without any problems.

    Concrete care after pouring

    Monolithic floor slab

    In the process of hardening of concrete, a large amount of heat will be emitted, under the influence of which intensive evaporation of moisture will begin. Lack of moisture will cause cracking of the concrete. Therefore, during the first few days after pouring, you will need to regularly moisten the stove with water.

    You can pour water in buckets (2-3 buckets per call) or through a hose with a spray. You can pre-put old rags on the dried concrete (sackcloth is better) and pour water on them. In the heat poured concrete cover with polyethylene, because due to too fast drying the plate may crack.

    The formwork can be removed for about 10 days after the last wetting. In general, the plate will gain strength 3-5 weeks. After this period, it will be possible to proceed to the implementation of further planned construction work.

    Thus, it is possible to arrange a monolithic overlap by yourself. At the same time, you will spend much less money on arranging the necessary structures than in the case of buying ready-made factory-made slabs. Follow the instructions and everything will turn out.

    Video – Monolithic overlap with their own hands

    Sources:, rukami /,

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