Fixed formwork from a professional sheet for overlappings. Lightweight monolithic overlap on a profiled sheet - constructive, experience of portal participants

Today, in the process of modern individual housing construction, as a rule, when constructing floors, reinforced concrete ones, especially monolithic floors on corrugated board, are becoming more and more popular.

During concreting, the corrugated board is used as a fixed formwork, and during operation it provides external reinforcement.

What is it, how is it different and what are its advantages in comparison with standard ceilings, how is it installed?

Flooring from corrugated board is used in a wide variety of areas of construction work: the construction of a garage, terraces and other buildings.

Ceilings: profile or reinforced concrete?

Monolithic overlap on corrugated board, in contrast to reinforced concrete, which implies pouring using a specially designed formwork, it helps to obtain a finished ceiling upon completion of the work, which does not require additional modifications and / or finishing. Decking, as already noted, will carry out reinforcement.

The possibility of using various types of profiled sheets when equipping floors should be noted as a very important advantage, since the section can be made ribbed if desired or necessary. Due to this moment, the strength and reliability of the ceiling are significantly increased, in addition, it is possible to reduce the consumption of reinforcement and concrete during the construction process.

The overlap device using a profiled sheet implies that the flooring in question performs the function of non-removable formwork, to which concreting will be applied in subsequent stages, and the metal frame, consisting of metal columns and beams, will be perceived as a support. Such a design allows (one might even say requires) the use of light building materials of low strength during the installation of walls.

Loads on the frame

This technology has gained the right to exist due to the fact that the load of interfloor ceilings using a profiled sheet does not fall on the wall, but on a completely durable and reliable metal frame.

When using the overlap according to the profiled sheet as building material for walls, a foam block or gas block can be recommended, which are also used for thermal insulation.

There is an interfloor ceiling made of profiled sheet and another no less significant advantage.

The construction of a large building involves the use strip foundation, for construction materials for which significant costs are required.

But the previously noted transfer of loads to the frame, which entails the possibility of lightening the walls, leads to a decrease in loads on the foundation. As a result, instead of a material-intensive strip foundation, you can choose a different type of foundation (for example, a column foundation), which will spend significantly less money and time, and, possibly, even labor costs will be less. It is worth noting that in the column foundation, each individual column will take the load from only one column of metal frames.

At the head of such a foundation, it is necessary to cut out a small grillage, the calculation of the section of which is carried out using the given wall thickness and the estimated step between the foundation columns.

Thus, analyzing the above, the installation of ceilings according to the profiled sheet entails a significant reduction in the cost of labor and financial resources, as well as temporary ones, because the process of building a building is significantly accelerated.

The device of overlappings using a profiled sheet

The design of monolithic ceilings for corrugated board must be carried out in accordance with the requirements of SNiP 2.03.01-84 "Reinforced concrete and concrete structures”, SNiP II-23-81 “Steel structures”.

Initially, regardless of whether corrugated board is chosen as a building material or not, planning must necessarily include the calculation of the future floor, which requires data such as:

• the exact dimensions of the structure being built;
• load calculations that are made directly by the floor.

With the help of these data, it is possible to correctly determine the dimensions of metal columns, beams, etc.

Columns, as a rule, are made of metal pipes, both round and square. For the production of blocks, the presence of metal I-beams and channels is often used.

It is worth paying attention: the distance between the beams during the laying process and the determination of their cross section are directly dependent on the type of profiled sheet used in the flooring device. The greater the height of the wall profile sheet, the smaller the step between the beams.

In order to independently perform the most accurate and correct calculation of the beam laying step, it is better to contact either the implementer or the manufacturer of the corrugated board for the required information. They can provide information on the necessary parameters of the building material, on the main types of profiled sheet, its characteristics, load-bearing capacity, etc.

Consider an approximate calculation

We take the following data as a basis: the gap between the beams is 3 m, the profiled sheet of the TP-75 brand is selected, the thickness is 0.9 mm.

1. The most high-quality fastening of corrugated board to the metal bases of the beams is considered to be the use of 32 mm self-tapping screws with a reinforced drill (so-called armor-piercing), through which it becomes possible to drill channels without first using a drill.
2. Fixation must be carried out at each junction of the profiled sheet and the overlapping beams. Therefore, if the corrugated board is laid on 3 beams, then it must be fastened at 3 points, if laying is carried out on 2 beams - at 2 points.
3. In addition to fixing the profiled sheets to the beams, it is also necessary to fix them at the junctions with each other. For this, you can also use the indicated armor-piercing self-tapping screws, but shorter, for example, 25 mm. They are screwed at a distance of about 400 mm from each other.
4. When the corrugated formwork is completed, the next step is concreting. With regard to floors, it is always necessary to take into account its minimum thickness, which, as a rule, is not more than 8 cm without the thickness of the profiled sheets themselves. Concreting is recommended to be used with concrete grade M-25 (another designation is M-350).
5. Before laying concrete, it is necessary to prepare profiled sheets. To do this, below, in the center of each span, between the beams, it is necessary to establish the presence of temporary supports (sticks can be used as them) from the floor directly to the profiled sheet. These actions help to prevent the possibility of subsidence of the corrugated board under the load of the laid concrete. As soon as the concrete mortar dries, the stick supports can be removed.

Do not forget that the essence of the profiled sheet in the process of subsequent operation is reinforcement. Therefore, the thickness of the concrete masonry is calculated based on the strength and deformation of the profiled sheet. The minimum is 30 mm, if there is no concrete screed, the calculation is 50 mm. The profiled sheet is laid with wide corrugations down. In the case of a hole size up to 500 mm across the flooring, it is necessary to reinforce the ceiling in the form of longitudinal rods. Otherwise, along the contour of the hole, it is necessary to provide additional elements of the beam cage in order to transfer the load from the weakened areas to the girders.

First of all, it is necessary to determine the required length of the corrugated sheet, for which it is best to take into account the support not according to the standard version on 2 beams, but on 3 - this will allow for the deflection of the profiled sheet during operation.

It should be noted: if concrete is laid in several passes, it is necessary to take into account how many days this or that section has dried. Then additional supports from under the spans with dried concrete will be removed in a timely manner. At the same time, keep in mind that concrete will reach 80% strength no earlier than 10 days from the date of laying, subject to warm weather. In the cold season, concrete masonry can dry up to one month.

In hot weather conditions, during the period of flooring on corrugated board, concrete should be regularly moistened, which will prevent premature accelerated evaporation of moisture as a result of strong heating of profiled sheets due to high temperature environmental air.

Like many other construction works, the technology for implementing a monolithic floor using corrugated board is not particularly difficult and does not require specially acquired skills.

The most important stage is the development of the theoretical part, which includes:

• determination of the frame material of the metal structure;
• correct determination of the types and sizes of profiled sheets;
• competent calculation of the sections of the reinforcement required in the process of manufacturing the frame, etc.

An important factor is the availability of the necessary tools:

• screwdriver and self-tapping screws, preferably 32 with a drill;
• drill and the presence of drills;
• rule;
• knitting hook and wire.

These are various levels, a plumb line, a lace, a square and a tape measure. If concrete is poured manually, then a concrete mixer and a mortar container will be required.

If the entire direct construction process can be performed independently, then it is still recommended to entrust the calculation for each parameter to a highly qualified professional.

The device of ceilings from corrugated board should be carried out strictly according to the developed and approved plans and drawings, in accordance with the above requirements.

Nevertheless, in order to prevent all sorts of errors and inaccuracies in the performance of construction work, you can invite a team of qualified specialists, but it is first recommended to ask about their reputation and feedback about them.

5 / 5 ( 1 voice )

Use of progressive building methods and application modern materials increase the rate of construction of new buildings. Overlapping according to the profiled sheet is in demand and popular today in the construction of objects - terraces, garages, residential buildings, enterprises.

Traditionally, concrete slabs were used in the construction of buildings. With their help, high-rise buildings were built. The lifting of heavy plates was carried out by lifting equipment, heavy physical labor of workers was used. Ceilings from corrugated board have reduced the complexity of operations. Would you like to know how to apply a profiled sheet for floors? This work can be done independently by reading the material of the article.

At present, during individual construction, during the installation of floors, a monolithic floor is increasingly being made along the corrugated board

Basic information

Filling floors with a profiled sheet base is the creation of a monolithic slab with increased strength and safety margin. In the manufacture, a galvanized profiled sheet is used, a material with polymer protection, which is the basis. It performs the function of a stationary formwork, poured with concrete mortar. The power load is perceived by metal frames.

Ceilings based on profiled sheet and concrete mortar, with proper calculation and in accordance with all design rules, have a long service life and high strength. Compliance with all necessary requirements and proportions determines the reliability of the building and the safety of people in the building.

Advantages of corrugated board

When planning to use corrugated board for structural floors, you should familiarize yourself with the characteristics of this material, namely:

• wide range of applications. Profiled sheets are used as facing, roofing material, as well as for the purpose of arranging fences;
• corrosion resistance. The production technology of corrugated board provides for the application of a special anti-corrosion coating that increases the service life up to 25 years;

Overlappings of this type are used in the construction of multi-storey public and industrial buildings with non-standard spans.

• light weight. The mass of the profiled sheet does not exceed 8 kilograms, which reduces the load on the load-bearing structure;
• workability and manufacturability. Sheets of material are easily attached, can be cut;
• increased strength. The professional flooring maintains the raised efforts;
• acceptable price. Its low cost has made it a material accessible to the masses;
• aesthetics. Different colors of corrugated sheets allow you to harmoniously fit them into the exterior;
• transportability. Light weight and compact dimensions make it easy to transport the material;
• environmental friendliness;
• resistance to natural factors. Decking is not affected by weather conditions. Possesses the increased resistance to the alkaline and acid environment.

Features of a monolithic design

Interfloor overlapping from corrugated board differs from the usual design by special formwork reinforcement, which allows you to get a finished ceiling that does not require additional finishing.

The possibility of using various types of profiled sheet in the construction of ceilings is quite an important advantage.

Advantages:

• the possibility of reducing the consumption of concrete mix, associated with the presence of "waves" of various sizes;
• reduction in the amount of material for reinforcement;
• increasing the strength of the base;
• weight reduction of the structure;
• uniform redistribution of the load;
• ability to use the lungs wall materials, including foam and aerated concrete blocks.

The profiled sheet for ceilings has been used relatively recently. The method of overlapping on corrugated board involves the use of formwork and concrete. In a short period of time, the technology has become in demand.

One of the distinguishing points is the possibility of constructing a column foundation for the structure, replacing the traditional tape one. The load that each column will take is transmitted only by a specific part of the frame.

The monolithic reinforced concrete base is a solid slab concreted on a profiled sheet. Structural supports - brick walls, concrete, reinforced concrete elements, steel frame. The slab is poured with a span of 1.5 to 6 meters in length. The size of the concrete shelf above the surface of the sheets is determined by calculation and is at least 30 mm. If openings are made in the surface to be concreted, reinforce a monolithic array around them by welding additional reinforcement in the places of the holes.

The profiled sheet used as reinforcement must have a galvanized or some other coating that will provide it with resistance to corrosion.

Preparatory stage

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, a slightly updated version of the first version. 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 it comes to industrial premises, such exterior finish more than enough. According to the developers of the service station, lightweight ceilings along the profile compared to the usual 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 an overlap with a stairway is planned, 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 an alternative option - an unsupported monolithic ceiling along a 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 a non-removable formwork, and the reinforced reinforcing cage takes the main loads. 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 thoroughly 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 through a meter and inserted pieces of wire 6 mm thick, 10 mm long into them, and instead of asterisks 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.

Formwork is a kind of form for cement-sand mixture, which allows you to form the correct geometry of the walls. Builders use both removable/temporary and non-removable/permanent formwork for the foundation. The second option allows you to save time and energy on dismantling work, as well as insulate and / or strengthen walls, so it is increasingly used not only in industrial, but also in private construction.

Basic requirements for fixed formwork for the foundation

Consider what properties a fixed formwork should have.

• Moisture impermeability of material and tightness of seams. In the absence of this characteristic, the formwork will let concrete through, which will lead to overspending of the mixture and make it impossible to build a wall.
• Structural strength. This is necessary so that the formwork can withstand the pressure of the concrete mixture from the inside and the earth outside (at the foundation level) without deformation and cracking.
• The correct geometry of the elements. From blocks of different thicknesses or with irregular angles, it would be impossible to build even walls and 90-degree joints between them.
• Long period of operation. The longer the formwork is potentially able to last, the higher the likelihood of a long life of the whole house. If the formwork collapses quickly, the unsupported walls may not be able to bear the structural loads. In cases where the formwork does not have load-bearing properties, its destruction will lead to deterioration appearance due to delamination decorative finishes facade.

Fixed formwork is an important element of an energy-efficient home

Table: advantages and disadvantages of fixed formwork

Fixed metal formwork

To ensure uniform wall thickness, sheets of metal formwork are connected with metal studs.

Metal formwork is one of the most expensive, therefore it is used mainly in industrial construction. It is made from sheets of aluminum or steel 1–2 mm thick on a metal frame and connected with anchors, pads or locks. The type and number of clamps are calculated in such a way that when the concrete is poured and hardened, the sheets do not bend either inward or outward.

When the formwork is made to order for a specific building, the manufacturer's foremen themselves carry out a test assembly of the structure, and only after confirming the suitability and completeness of all parts, the order is sent to the buyer.

Metal formwork has the most precise geometry. Permissible deviation in the parallelism of the sheet faces - no more than 2 mm over 1 m of the length of the product.

In order to prevent premature oxidation and destruction of the metal due to contact with concrete and groundwater, the sheets of the future formwork are carefully coated with paint and grease during production. Often, galvanized steel is also used, or a method is used powder coating, which forms a dense polymer film on the sheet. But if welding is used during installation (welding sheets to the frame or reinforcement to sheets), it will be necessary to reapply a protective compound (grease, mastic, paint) on the places damaged by temperature.

Powder coating of metal sheets is one of the most effective methods their protection against corrosion

Metal is well suited for buildings with complex geometry, since thin sheets are easy to bend at any desired angle, make a round or arch. The finished walls are very neat and smooth, if desired, they can be left without decorative finishes. Architects recommend using metal formwork in areas with complex loose soils.

In order to prevent the flow of concrete, the joints of the metal formwork are connected especially carefully.

But experts note some disadvantages of metal formwork:

• significant weight of steel sheets, which requires the use of special equipment;
• the need for additional thermal insulation of walls and foundations;
• sheet grease is easily wiped off and stains workers.

Installation of aluminum sheets for wall formwork under the force of a pair of workers

Aluminum sheets with the addition of silicon, which weigh much less than steel sheets and do not require protection from the external environment, will help minimize labor costs for the transportation and installation of metal formwork.

Fixed formwork made of reinforced concrete blocks

Reinforced concrete formwork blocks are recommended for large construction projects, at least a three-story private house. Since they have increased strength characteristics, in smaller buildings such a margin of safety will be redundant. Thin-walled blocks are great for arranging the foundation of a capital fence.

Reinforced concrete formwork blocks are installed with an offset

Reinforced concrete formwork blocks have the following advantages:

• allow you to save cement-sand mortar, due to the significant wall thickness;
• suitable for the construction of basements of any depth, as well as interfloor ceilings;
• mounted with minimum width seams;
• provide a building service life of several hundred years.

The best formwork is obtained from reinforced concrete blocks with indicators F75 (frost resistance), W4 (water permeability), 6% (water absorption), 350 kg / cm 2 (mechanical strength).

An example of the location of the reinforcement in the formwork of reinforced concrete blocks, designed for two rods

Among the shortcomings of reinforced concrete blocks, there are:

• high weight (a block of 510x400x235 mm weighs 30 kg), due to which it is transported only by trucks, and only workers with a crane mount it;
• high price - about 500 rubles per unit.

Claydite-concrete blocks do not have such shortcomings. Providing high strength of the walls, these analogues of reinforced concrete blocks also do not require insulation of the house, since they already contain a heater - expanded clay.

Fixed plywood formwork

Moisture-resistant plywood is most often used for formwork, but even in this case, this material is usually used to create a temporary form. After all, the service life and weather resistance of a laminated plywood sheet is an order of magnitude lower than the same parameters of a concrete wall.

Permanent plywood formwork is acceptable in the following cases:

• in the manufacture of a temporary structure (for example, little house, in which the owner lives during the construction of the main house);
• during the construction of non-residential buildings (chicken coop, barn, wood storage);
• when it is necessary to save on construction as much as possible;
• if the walls and foundation are insulated along the outer contour and the plywood is completely protected from external influences.

In addition to dubious durability and strength, plywood formwork will require both a lot of labor and careful handling. Since the sheets do not have a tongue-and-groove system and special joints, you will have to assemble the structure with self-tapping screws, additionally seal each joint and make an external crate with supports (so that the plywood does not bend). In addition, non-waterproof plywood swells and peels from water, and laminated plywood repels the concrete mixture and never forms a monolithic wall with it, so it is very important to find a waterproof material with good adhesion.

Technoblock - an example of the successful use of plywood in formwork

Designation in the picture:

• 1 - decorative facing layer;
• 2 - a layer of insulation;
• 3 - plastic supports for fittings;
• 4 - concrete pouring (a cavity is provided for it in the block);
• 5 - plywood sheet.

As a result, despite the cheapness and environmental friendliness of plywood, experts recommend using it only for temporary formwork. For a permanent one, it is better to use a technoblock - a composite product with an inner plywood layer.

Fixed formwork made of wood concrete

Arbolite is a relatively new, but already time-tested material. Formwork blocks made of concrete and wood chips began to be made recently, but such a mixture was used to insulate floors in Soviet times. Arbolite blocks are much cheaper and lighter than reinforced concrete blocks, so they are actively used in individual low-rise construction.

In some models of wood concrete blocks, a layer of insulation is provided - stone wool or polyurethane foam

Compared to other types of fixed formwork, wood concrete blocks:

• they are easily cut with tools for working with wood, which allows them to be adjusted on the spot to the desired parameters: cut corners, make arched roundings, cut out fragments for better adhesion of walls at the corners of the building, reduce height / length;
• mounted quickly and without special equipment (1 m 2 of the wall is only 8 blocks);
• provide high strength, sound absorption and thermal insulation with a smaller wall thickness (compared to brick and polystyrene foam);
• safe for the health of others, waste can be industrially processed;
• strong enough for fixing drainpipe clamps and loaded elements of facade systems (guides for hanging siding, etc.);
• are not afraid of fires (can withstand up to 90 minutes of open fire);
• frost-resistant, suitable for regions with a harsh climate.

The disadvantage of wood concrete is its water permeability, therefore it is recommended to use it for building walls on a ready-made waterproofed strip or slab foundation. The use of wood concrete for arranging the foundation is undesirable, since it will need to be very carefully protected from moisture.

An example of the arrangement of formwork from wood concrete and brick

Arbolite is produced in the form of hollow blocks and panels. In the second case, the panel serves only as the inner contour of the wall, and the outer one must be equipped with bricks. The cavity between the materials is filled with concrete and reinforced, as with other types of formwork. This option is more difficult to install, but the finished house turns out to be warm (wood concrete), beautiful (brick) and durable (merging the strength characteristics of the three materials).

When buying blocks and slabs of wood concrete, pay attention to the eco-label, as some manufacturers use binders that are harmful to health (phenol, naphthalene). Be careful, plasticizer toxins can be released from the material even at room temperature.

Manufacturers of wood concrete formwork blocks offer options for both high-rise buildings and small buildings. Be sure to consult with a consultant so as not to spend extra money on concrete for pouring thin-walled blocks or not to mistakenly take blocks with too small voids.

Fixed formwork made of CSP

DSP (cement particle board) or sawdust concrete is another variation of a mixture of cement and crushed wood. It differs from wood concrete in the type of binder and the addition of sand. Therefore, DSP is a denser, stronger and heavier material, and its thermal insulation is worse than that of wood concrete.

Cement particle boards can serve as a finishing material when covered with decorative mineral chips.

Among the advantages of wood concrete formwork:

• the material breathes, so the house does not need to be equipped with forced ventilation and deal with the greenhouse effect in other ways;
• DSP is able to withstand fires, its fire resistance is confirmed by laboratory studies;
• plate consists of natural materials therefore does not harm nature and health;
• gives the house high strength: with a thickness of 25 cm, the wall is able to withstand three times more loads than a brick wall of the same thickness;
• DSP is resistant to sudden changes in temperature, therefore it is suitable for regions with a sharply continental climate;
• the material has sufficient stability and geometric stability so that the distance between the floors can be 2.8–3 m;
• you can build houses using cement-bonded particle boards even in winter, until the temperature drops below -20 ° C;
• DSP requires minimal finishing, inside the house it can be painted or wallpapered without putty.

An example of creating a reinforced foundation formwork from cement-bonded particle boards

European builders have been using CSP fixed formwork for more than 25 years, so there are many houses that confirm the durability and reliability of this material. Cement particle boards are well suited for both individual and multi-storey buildings, even in the harsh northern climate.

Fixed formwork from profiled sheet

A profiled sheet, profiled sheet or corrugated board has also found its use as a fixed formwork, although it is much more often used for the manufacture of fences, roofs, and outbuildings. Important: the profiled sheet is only suitable for arranging composite floor slabs and for large spans (from 5 m) requires additional temporary supports. For the construction of walls, this material is not used because of its small thickness, which reduces its resistance to mechanical stress in a vertical position.

An example of a ceiling structure with a profiled sheet base

Formwork made of this material attracts builders with such features:

• the metal is completely protected by galvanization and / or a polymer layer, so it does not rust;
• in industrial buildings, the material can be left without decorative finishes, the ceiling is visually pleasing and practical;
• profiled sheet performs not only the function of a form for concrete, but also serves as sheet reinforcement;
• corrugated board transfers the load to the metal frame of the building, so the internal walls do not carry heavy loads and it becomes possible to save money by building them from lightweight materials (aerated concrete, sandwich panels);
• sheets of small thickness are simply cut with scissors for metal, formwork of any shape can be created from them.

To ensure good adhesion to concrete, choose special profiled sheets with teeth for formwork.

It looks like an interfloor overlap based on corrugated board from the inside of the building

Fixed formwork made of profiled sheet is used mainly in industrial construction, as it requires construction metal frame building and metal floor beams. It is not suitable for an individual house, as it will be unreasonably expensive.

Fixed formwork made of expanded polystyrene

Expanded polystyrene / polystyrene is the most popular material for fixed formwork. Its demand is due to factors such as:

• light weight, which makes it easy to transport;
• tongue-and-groove connection system for the most simple installation;
• speed of laying (foam blocks of fixed formwork are larger than concrete ones, so work progresses faster);
• variety of types (reinforced, with protective impregnations);
• thermal insulation properties, due to which the house does not need additional insulation;
• soundproofing;
• biological inertness that prevents the development of mold, moss, etc.

Examples of polyurethane foam formwork blocks of different configurations

Opponents of polystyrene formwork point to its fire hazard and low degree of environmental friendliness. Even if you buy eco-labeled materials, this does not guarantee that the formwork will not harm your health or nature.

It is also important to keep in mind that foam formwork will be a good choice for buildings with a simple shape, since the range of corner and rounded blocks does not yet satisfy all consumer needs.

Fixed formwork made of glass-magnesite

Glass-magnesite sheets or LSU have been used as permanent formwork since the middle of the 20th century for the purpose of constructing heat-insulated houses. The material consists of a mixture of magnesium oxide and chloride, perlite, sawdust, fiberglass and polypropylene fabric. Not all components of glass magnesite are natural, but the finished composition is completely safe for people.

Different options of glass-magnesite sheets with decorative finishes

LSU is a great option for building or renovating a house with a weak foundation. Since the sheets themselves and those used for pouring are light concrete mixtures weigh much less than bricks, reinforced concrete blocks and other traditional materials, they do not load the structure of the building so much.

Among the advantages of glass magnesite:

• multifunctionality: it is suitable for creating foundations, walls, ceilings, fences, etc.;
• high thermal insulation, which is associated not only with the properties of the formwork itself, but also with the advantages of the filler (fiber foam concrete grade D250-D320, concrete with polystyrene foam balls M300);
• fire resistance;
• complete moisture resistance, which makes the material suitable for the construction of baths and saunas, use in areas with a humid climate and in wetlands;
• small wall thickness with LSU formwork will save space inside the house;
• the rough surface of the sheets is easy to veneer with clinker tiles, decorative plaster or any other finishing material;
• the sheet can be slightly bent if necessary for the construction of a half-tower or other decoration of the house (the radius of curvature is 3 m).

If you plan to cut LSU boards on site, purchase spare jigsaw blades. This material wears out nail files several times faster than wood concrete and plywood.

Glass-magnesite sheets will come to the court at all stages of building a house

Glass-magnesite sheets, like arbolite, often form only the inner contour of the formwork, while the outer one is most often built from decorative bricks. As a result, the exterior finish is unnecessary, and a thin layer of putty will be enough inside. The technology is suitable for building houses up to 5 floors on a ready-made strip / slab foundation. In addition, it requires more time and effort than the use of expanded polystyrene or CSP formwork (excluding decorative finishes).

So far, glass-magnesite sheets are produced only in China and Korea; LSU quality control is also carried out there. There are no domestic analogues of this material.

Installation instructions for fixed formwork from prefabricated blocks

We will consider the technology of building a foundation from ready-made hollow blocks using the example of lightweight concrete products. Unlike reinforced concrete blocks for high-rise buildings, these "bricks" can be installed by hand without a crane and a manipulator.

1. Prepare a pillow under the block foundation by filling and tamping down layers of sand and fine gravel. A thin screed should be poured over the pillow to simplify the further laying of the blocks, as well as to avoid concrete leakage when pouring the foundation.
   

   Before installation, a sand and gravel cushion must be shed with a thin layer of concrete

2. Pull the thread along the trench and lay the first layer of blocks on the pillow, trying not to deviate from this guide. It is necessary to mount so that the gap between the elements is minimal. If the gap increases significantly throughout the trench, the cause may lie in the unevenness of the pillow. In this case, the row needs to be disassembled and a more even base made.
   

   Due to the correct geometry of the blocks, the foundation tape is smooth and clear.

3. Connections between walls should be provided with special blocks of slightly greater length. If there are none, a recess should be made in the universal blocks, as in the picture. This will ensure reliable adhesion of perpendicular foundation tapes.
   

   At the junctions of internal and external walls, you need to put special corner blocks

4. Lay metal or fiberglass reinforcement in the slots of the blocks. For low-rise construction two parallel rods are enough, but if necessary, three can be arranged.
   

   The blocks have special grooves for reinforcing rods.

5. At the junction of the walls, the bars must overlap so that the length of the free end is at least 2 cm.
   

   Pay attention to the location of the upper and lower rods in relation to each other, they should form a regular square

6. When the length of the rod is not enough, it can be increased by tying a new rod with a special thin wire. It is advisable to make 2-3 dressings in different areas of the overlap.
   

   Bandage the reinforcement should be with an overlap of 15-20 cm

7. Install the second row of concrete blocks exactly on top of the first. Do not allow even small deviations, if necessary, trim the position of the block with a mallet.
   

   Install the second row of hollow blocks on top of the first

8. Pour the prepared formwork with a liquid cement-sand mortar so that the concrete level does not reach the grooves for the reinforcement.
   

   The concrete level should be slightly above the middle of the top row of blocks.

9. Before the concrete begins to dry, try to expel excess air by piercing the space inside the formwork with a reinforcing bar from top to bottom. After that, place the reinforcement vertically, especially carefully strengthening the outer corners and joints of the walls.
   

   Vertical reinforcing bars can be installed one by one at a distance of 1.5 m from each other

10. After the concrete has dried, proceed to build the foundation. Install and bandage the reinforcement, mount two new rows of blocks and fill the formwork with concrete. Continue like this until the foundation reaches the height you want.
    

    New reinforcement is installed on top of the concrete screed

11. The last row of foundation blocks is poured until a flat horizontal surface is formed. While the concrete is not dry, it can be trimmed with a small board or a long trowel for plaster.
    

    The foundation is ready for the construction of the walls of the future house

The foundation of concrete hollow blocks for a private house according to the described technology is mounted by two workers in 2–3 days, taking into account the time for setting the concrete of the first layers.

Comparison of the costs of creating a foundation from solid and hollow reinforced concrete blocks and a monolithic one with temporary formwork

The comparison shows that a foundation made of hollow concrete blocks is 18% cheaper than a solid one and 36% cheaper than a strip monolith filled with temporary wooden formwork. This is achieved by saving on the amount of reinforcement, reducing labor costs, the amount of concrete, etc. But building walls from reinforced concrete blocks will turn out to be too expensive (compared to polyurethane foam, wood concrete), it is better to use it only for the foundation.

Do-it-yourself fixed formwork

Consider the process of creating fixed formwork from sheet materials with independent cutting using the example of EPS (extruded polystyrene foam).

1. Dissolve the sheets into fragments corresponding to the width and length of the compacted trench. From the remains, cut out strips for sides 20–25 cm high. The total length of the sides should correspond to the double perimeter of the trench + 20% for overlap at the corner points.
   

   You can cut sheets of expanded polystyrene not only with power tools, but also with a hand saw

2. Lay the sheets in the trench so that the sides rest on the XPS layer and do not touch the ground. Secure the sheets at the corners by piercing the material with CBT system plastic ties.
   

   When laying XPS sheets in a trench, try to minimize gaps

3. Install the halves of plastic ties between the vertical sheets and fasten them together. If the system does not click tight enough, seal the connections with pliers.
   

   Plastic ties are easy to install by hand

4. Install reinforcing bars above and below the horizontal braces. To keep the metal in the thickness of the concrete, place pieces of polystyrene foam under the bars. Special grooves on plastic ties will help maintain the same distance between the reinforcement bars throughout the foundation.
   

   Both metal and fiberglass reinforcing bars are suitable for reinforcement.

5. Tie the rods together with a thin wire folded 2-3 times. In the same way, the reinforcement can be tied to plastic ties.
   

   Installed reinforcing rods must be tied with a thin wire, welding is unacceptable

6. Build up the foundation with whole sheets of XPS, after attaching narrow strips of the same material to them with plastic clips. Arrange the prepared sheets as shown in the picture. When installing, pay attention to the location of the grooves and ridges on the sheet.
   

   We begin to increase the height of the foundation

7. Attach the vertical sheets to each other with ties, install and tie up the reinforcement according to the technology described above. You should get at least two plastic-reinforcing belts, approximately at a distance of 10 cm from the top and bottom edges of the sheet.
   

   Plastic spacers between the plates are installed in the same way

8. Fasten the stopper plate to the sharp ends of the plastic ties and cut off the ends that are left free.
   

   The protruding tails of the screeds are easy to cut with wire cutters

9. Fill the reinforced formwork with cement-sand mortar. To prepare concrete, you can use your own concrete mixer, but you will need a lot of mortar. If you doubt that you can pour the entire foundation in a day, it is better to use the services of an industrial concrete mixer tank.
   

   Pouring concrete foundation

10. Remove air bubbles with a construction vibrator and level the concrete surface. In this case, it is impossible to expel air with a reinforcing bar, since the metal will damage the formwork, easily piercing the XPS sheet.
    

    The upper plane of the concrete layer must be at the level of the outer layer of the formwork

After the concrete of the foundation has completely hardened, you can continue pouring the walls using the same technology, but such a foundation can also be used with other materials.

Video: technology for building a house with fixed formwork from chip blocks

When giving preference to one of the fixed formwork options, consider not only your financial capabilities and labor costs, but also the purpose. For example, in areas with swampy soil, you should not use blocks based on wood chips, and in cold regions, you should pay attention to a material with a minimum thermal conductivity. In this case, you can quickly build a warm house without extra financial costs.

Do you need high-quality corrugated board for floors, screeds or formwork? In the company "Metallotorg" you can buy at low prices sheets 0.5-0.8 m in size made of high quality steel from leading manufacturers. We will deliver as soon as possible in Moscow, Moscow Region and Central Federal District. Self-delivery is possible - the warehouse is located near the Moscow Ring Road.

For formwork, creating floors, if you focus on the brand of rolled products, a carrier is used corrugated board with H and HC marking. For these purposes, it is the ideal material. Strong steel of different thicknesses, sufficient for the design loads, having a shape that provides the desired rigidity of the material, is able to reliably cover large surfaces. And at the same time, with minimal cash and labor costs.

Monolithic ceiling on corrugated board is easy to install. It does not require high qualifications and the use of special devices. The desired shape is easily and quickly assembled and fixed without damaging the sheets with self-tapping screws (with rubber gaskets). Joints in the most important areas can be glued with silicone sealant. It is the simplicity of creating structures that has become one of the reasons for the great popularity of this type of rolled metal. But this is not its only merit.

Decking for formwork:

• has a special relief shape with a high corrugation (for example, sheets of the HC35, H60, H75, H114, etc. brands);
• has increased strength due to high quality metal and additional stiffeners;
• in the presence of galvanization on the surface, the material is not subject to damage due to atmospheric influences.

Formwork and screed on a profiled sheet - aesthetics, reliability, durability

The creation of a fixed formwork from a profiled sheet significantly reduces the time of installation of additional structures. The corrugated board used as formwork (holds concrete until the mixture hardens within the desired shape) can have different geometries. Facades of non-standard shapes are created from it. Profiled sheets for formwork help to save on interior decoration, in particular, industrial buildings. This durable and convenient metal material is used in structures flat roofs, interfloor ceilings, as a fixed formwork for ceilings. Usually, sheets H60, H75 and H114 are used for these purposes. The choice of thickness and brand of the bearing profiled sheet is made at the design stage.

The screed on corrugated board is used where it is impossible to pour a thick screed. It turns out to be much thinner and exerts a significantly lower load on the base. Such a screed is quite strong. Profiled metal sheets can act as an additional base, prevent deformation and hold the poured new monolith in place. This method of screeding is advisable on the first floors of private houses, in which there is soil under the flooring. And also on the balcony in a residential apartment, where more significant loads are planned for the coating. You can check with our specialist what brand of corrugated board for fence formwork, ceilings or screeds you need. Important parameters are: steel thickness, profile and sheet size. It is recommended to purchase sheets of a suitable size right away, since the material loses its valuable properties at the incision sites, due to the fact that the protective layer is broken.