Formwork is a kind of form for a 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 the 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 a deterioration in appearance due to delamination of the decorative facade finish.

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

Table: advantages and disadvantages of fixed formwork

Advantages	Minuses
Ease of erection, the final result is less dependent on the skill of the workers (compared to self-made removable formwork).	In houses with fixed formwork, high humidity is often observed, which makes it necessary to equip a powerful ventilation system.
Good heat and sound insulation (compared to buildings made of brick and reinforced concrete slabs).	The impossibility of construction in the cold season, since a large mass of concrete hardens poorly at low temperatures.
Ease of carrying out finishing work due to the even surface of the formwork without cracks and differences in wall thickness.	The need for additional wetting of concrete during a hot period in order to prevent cracking of the walls.
Reduced construction period compared to houses made of brick, stone, gas blocks.	Buildings with a metal reinforcement cage must be grounded as quickly as possible so as not to expose people to the risk of lightning strikes.
The durability of buildings with reinforced concrete formwork is 300 years or more.	Difficulty in dismantling during alteration and reconstruction, especially if the filling was reinforced with metal rods.
The technology is suitable for the construction of buildings of any size and number of storeys, from summer houses to shopping malls.	In case of fire, the formwork material can release harmful substances.
Minimization of construction waste (compared to construction technology with removable formwork).	With insufficient or incorrect external processing of polystyrene foam blocks, water, insects, and small rodents can get into the walls.

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 particular building, the manufacturer's craftsmen 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 powder coating method is used, 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 re-apply a protective compound (grease, mastic, paint) on the places damaged by temperature.

Powder coating of metal sheets is one of the most effective methods of 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 a minimum width of the 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, a small 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 curves, 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;
• the stove consists of natural materials, therefore it 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 corrugated sheet is used mainly in industrial construction, as it requires the construction of a metal frame of the 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 the lightweight concrete mixtures used for pouring 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 sufficient, 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 poured 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 coefficient of thermal conductivity. In this case, you can quickly build a warm house without extra financial costs.

Fixed formwork is a special design. The technology of building houses with its use has become quite widespread today, and this is no coincidence. Practice has shown that fixed formwork house- this is one of the most affordable types of building your own housing, which is distinguished by reliability, economy and ease of construction of the entire structure - building a house using this technology is comparable to the process of assembling a designer.

The essence of the technology is to assemble a single structure, that is, pre-installed blocks with special voids are assembled into grooves, reinforcement is laid on the lintels. Further, all cavities are filled with cement of a high grade of strength. Thus, the result is a monolithic reinforced concrete wall, insulated with polystyrene foam.

The construction of fixed formwork gives the result of a solid structure that does not require additional insulation. Quickly, economically, and most importantly - inexpensively.

The price of building a private house from fixed formwork is from 13,600 rubles per m 2

Stages of building a house from fixed formwork

Let's briefly consider the main stages of building a house from fixed formwork. There are six main steps in total:

1. Project selection- the most important stage, since the house is not built for one year, then the choice of layout and auxiliary factors should be approached very responsibly. Despite the fact that the construction of fixed formwork allows you to build houses up to 16 floors, it is low-rise buildings that are most widespread. Since expanded polystyrene can be easily processed, almost any design can be obtained. This makes it possible to build complex architectural forms from fixed formwork. A fixed formwork house can have various configurations, almost any layout, and includes the possibility of redevelopment, for example, adding some elements.

2. Foundation construction. The type of this construction is determined by the features of the construction of the house, the characteristics of the local soil, the level of groundwater and other factors. A fixed formwork house can be erected on a strip, columnar and precast concrete foundation. The most widely used strip foundation, as the most simple and reliable design. The depth of laying the foundation is approximately one and a half meters, below the level of soil freezing. This requires thorough earthworks, which increases the cost of building from fixed formwork. If you want to save money, you can equip the foundation without a basement. The savings will be 15% of the total cost of construction, while using a prefabricated strip-type foundation. For this type of house, waterproofing is mandatory.

3. After the foundation is ready, you can proceed to wall construction. Note that this process is as simple as possible and includes three main loops:

• - Installation of blocks;
• - Reinforcement;
• - Cementing.

The first row is attached to the foundation by vertical reinforcement. Further, according to the project, the houses begin to lay bars in the grooves of the blocks along the horizontal level. The same bars will be connected to the vertical reinforcement by twisting. The second row of blocks is laid by overlapping, which will create a solid and reliable structure. Cementing is done every two rows of blocks. Since expanded polystyrene has a high coefficient of thermal resistance, the walls can be quite thin, and additional insulation is not required. There will be significant savings on the material.

4. Stage communication includes a number of processes that are directly related to the previous ones. The project initially laid down the schemes for conducting communications to the house, while both during the construction of the foundation and during the construction of walls, these facts must be taken into account. The supply of water and gas pipes, electrical cables and other communication elements is carried out in conjunction with the construction of walls, where special inputs are equipped. All main communications can be laid inside the formwork - no boxes are required.

5. Stage exterior finish necessary, since polystyrene blocks have an unaesthetic appearance. For exterior decoration, you can choose almost any material, such as siding, natural stone, plastering with decorative types of plaster and many others - everything is limited by imagination and financial capabilities.

6. Interior decoration is a long and costly process. It is also determined by the financial capabilities of the owner of the house. The smooth surface of the blocks can significantly save on some finishing work. Walls can be plastered, painted or wallpapered. The type of finish is selected from your own preferences.

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Features of fixed formwork houses

So, we have already found out: what are the main stages of construction from fixed formwork. The main process includes the erection of walls. This is done strictly according to a certain technology. The basic principle of masonry is the displacement of each new row. The connection of polystyrene foam blocks is carried out with a slight pressure on the edges, due to which special locks are interconnected tightly and reliably. It is worth noting that the most important is the third row, which serves as a reference indicator for the alignment of the blocks along the vertical seams. After the formwork is built, the voids are cemented.

Pouring concrete in fixed formwork has its own characteristics. It is worth starting cementing from the corners, moving towards the center. This will help avoid the formation of air bubbles. A monolithic structure must be very durable. To achieve this result, it is desirable to use concrete of a strength grade of at least M200. For additional strength, gravel backfill is used with a gravel fraction of no more than 20. All pouring is done using a concrete pump. Also, construction from fixed formwork includes bayoneting - this is the process of compacting concrete (it is also carried out to remove air bubbles and more evenly lay layers). The solution is poured no more than two or three rows, while the surface is not leveled. This is necessary so that the new layer adheres better to the previous one. Note that the construction of simple walls and walls that have complex structural elements or ledges are erected equally quickly. The labor intensity does not change, while the finished house from fixed formwork will have any desired configuration.

Construction of a cottage from fixed formwork allows you to achieve significant savings in further operation. Since its heating does not require significant costs, the costs will be significantly reduced. This is due to the properties of expanded polystyrene, the material perfectly retains heat. Note that while saving on both materials and heating the house, the house will have a larger internal area, because the walls are thinner than those of a brick or other house. That is why the technology of fixed formwork is gaining more and more popularity. The effectiveness of the formwork has justified itself from a practical point of view, while the process does not include the dismantling of the formwork - the entire structure is completely monolithic. It is this fact that determines all the properties of the house from fixed formwork.

This technology is the most promising direction. In fact, it is a quick construction of a house. During construction, special tools are not required, ordinary saws, knives, shovels and containers for mixing concrete are enough. Since the blocks are very light, the walls can be built completely independently. However, this is not worth doing, since knowledge of the process is still necessary. Some unaccounted for nuances can lead to disastrous consequences. Best of all, if the house is built by professionals, the resulting housing will serve you for decades.

Building a house from fixed formwork is a reliable and fast way to get a modern, beautiful and economical home. The cost of such a house is much less than that of a brick one. The number of storeys of your house can be any, since polystyrene blocks allow you to get a fairly high house. If necessary, the house can be equipped with: a terrace, an attic, any complex architectural elements, such as a bay window and many other elements. A fixed formwork house can be reconstructed and improved, for example, by adding a terrace.

Advantages of fixed formwork

So, we found out that the technology of fixed formwork is quite simple and does not require capital investments. Let us point out some positive aspects of this technology.

Main advantage- This is the speed of building a house. In just 5 days, you can completely build walls! Such results with other technologies are unlikely to be achieved. Despite the fact that the polystyrene foam blocks are very large, their weight is relatively small. Due to this, the process of building walls is simplified as much as possible.

Further, one can note the high variability of the configuration of the walls. Styrofoam blocks can be easily processed, while some non-standard elements are already coming from the factory. This allows you to create any individual project at home to suit your needs. You can think of additional utility rooms or bathrooms. In addition, you can choose different floor options, that is, it is not necessary to make a monolithic floor, for example, you can equip either a wooden or prefabricated floor, reinforced concrete beams are also suitable.

Let's highlight some more advantages:

• - Low thermal conductivity of the walls. Home heating does not require significant costs;
• - Expanded polystyrene blocks do not absorb moisture and have high vapor barrier properties - such a house "breathes";
• - High sound and noise insulation properties make the house comfortable and protected;
• - The concrete with which the walls are poured is a symbol of strength, reliability and durability;
• - Unlimited architectural and other solutions used in the construction of the house, allow you to embody the most daring ideas and fantasies;
• - Rigidity and strength of the structure, which over time gives a minimum drawdown. The load is evenly distributed on the foundation base.
• - The service life of the house is not less than 100 years!

This is just a small number of advantages that are inherent in the construction of fixed formwork. It can also be noted that houses of this type are earthquake resistant. The operational properties are characterized by the frame structure, where there are no voids or "cold bridges". In addition, the formwork is resistant to aging and wear, temperature changes and other weather influences. In general, the construction of a house has a short time frame, since the construction scheme is clear and well-established, and has long established itself in practice. Each stage includes savings: monolithic walls are lighter than brick ones, so a solid foundation is not required; the walls are immediately insulated; since the walls have the correct geometry, they do not need to be leveled.

Disadvantages of fixed formwork

When building from fixed formwork, it is required to pay a lot of attention to the preparation of the concrete mixture. It must have a homogeneous mass. Additionally, you will have to check the brand of strength. If you choose low-quality concrete, then the walls will subsequently be less durable. It is also necessary to monitor the correct laying of the reinforcement.

Main difficulty when erecting walls from fixed formwork, this is a high-quality compaction of the concrete mixture. If these works are performed poorly, then "shells" may form in the wall, which will also affect the strength of the finished structure. This is unacceptable, as this will lead to the "floating" effect of the formwork. The last row of masonry requires special attention and a professional approach. The entire load from the roof will be perceived precisely by this row. It is important to equip the walls as vertically and rectilinearly as possible. Construction from fixed formwork requires the arrangement of scaffolding and special fasteners, which will determine the verticality of the walls and provide direct access to the height. It is unlikely that you will be able to do this on your own. Nobody needs a crooked house, so it is necessary that the construction be carried out only by professionals in this field.

When building walls, as we noted above, special tools are not required, however, some elements, if they are correctly applied during construction, are aimed at speeding up and simplifying the process. Difficulty is also noted in the arrangement of door and window openings, as well as corner openings, when making bay windows and other architectural forms. In this case, a professional approach of specialists is also required.

It is worth noting that the level of the walls directly depends on the level of the foundation. If the foundation is made poorly, then the walls will "float". If the walls are uneven, then it is impossible to compensate for the defect with the thickness of the solution - the house will have to be dismantled to the level of the foundation and rebuilt again. It is very costly both in time and money. Wall modules are sometimes additionally glued to achieve the desired strength. It also makes adjustments to the expense item.

As for the environmental friendliness of the material, it cannot be called one hundred percent, since liquid glass has its drawbacks. This requires the construction of mandatory ventilation in the house. Also of the shortcomings can be noted, the obligatory external decoration of the walls.

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We examined the features of construction from fixed formwork, its advantages and disadvantages of this technology. All this leads us to the conclusion: we need a reliable team, a quality project and a solution to other problems.

The company "Art Stroy Design" is ready to provide you with a range of services quickly, affordably and inexpensively. The accumulated experience allows us to give guarantees for all stages of construction. We employ only highly qualified specialists, which also acts as an additional guarantor for you. All details can be found on our phones.

The classic version of the form for the foundation and walls in monolithic houses is a temporary structure, which is made of wood and chipboard. Styrofoam fixed formwork is an alternative construction method that does not involve waste. This design increases the strength of the building and increases its energy efficiency, acting as thermal insulation. However, such material has some features that cannot be ignored.

Manufacturers of this material point to its many advantages over standard building formwork options. These advantages need to be known to every person who decides to use a non-removable type of polystyrene foam structure.

The advantage of a fixed formwork made of this material is, first of all, that such a structure has auxiliary functions. The main one is the organization of the form for the walls and foundation of a monolithic building. Due to its physical qualities, expanded polystyrene is a good insulation. This is a very important property, since this type of formwork is not dismantled after the concrete has hardened.

If formwork boards are used, they must be dismantled. Wood is not a thermal insulator, so Styrofoam blocks are considered a better investment. Fixed formwork made of this material allows you to build a lightweight concrete structure. Moreover, such a building retains 30-35% more heat than a building with an analogue of red brick. Thus, the use of expanded polystyrene allows you to reduce the cost of other materials from which the foundation or walls are made.

An alternative to polystyrene foam forms is plastic formwork. The price of such a design is slightly higher, but it is more reliable strength. Fixed plastic elements can be purchased at a hardware store or you can order them online.

Another advantage of such forms is that they protect reinforced concrete from moisture. In winter, this is especially important. As a result, thanks to polystyrene blocks, the service life of the foundation and walls is increased by approximately 20%. Quite often, it is this fact that pushes people to use such formwork for building a house. From expanded polystyrene, various (in shape and dimensions) elements are made.

Note! Building a building using polystyrene molds reduces financial costs by about a third.

The price of slab formwork made of expanded polystyrene, as a rule, is the determining factor in its choice. However, the most useful property of such forms is that their use allows to preserve the structure of concrete at low temperatures (but not below +5 °C). Concrete in this case hardens in the normal mode, which has a positive effect on its qualities after hardening.

In turn, pouring concrete material into a wooden form gives a completely different result. In such formwork (at low temperatures), concrete hardens faster, and its structure is broken.

Fixed formwork made of expanded polystyrene: design flaws

Such designs also have their drawbacks. Some of them are quite significant. For example, one of the most serious disadvantages is the fact that a building made using such formwork cannot be rebuilt. Therefore, it is recommended to think over its design in advance. In addition, all communications located in the structure must be laid at the construction stage.

A fixed formwork house is made subject to certain rules, which are very important to follow in order to get a reliable building that is resistant to adverse environmental factors. Blocks made of expanded polystyrene require careful installation. It is very important to maintain tightness, otherwise moisture will penetrate into the voids.

Another disadvantage of this technology for the construction of residential buildings is that polystyrene foam molds cannot be used at temperatures below +5 ° C. In such a situation, the concrete simply will not harden. In hot weather, concrete requires additional moisture, otherwise it will not harden properly.

It should also be noted that fixed formwork blocks made of polystyrene foam prevent normal ventilation of the concrete structure. The solution to the problem in this case is the installation of ventilation communications. This forced system will provide the necessary ventilation, while maintaining the high efficiency of a fixed structure.

Types of fixed formworkdepending on the material of manufacture

Before starting installation, it is necessary to study the various options for fixed formwork that can be purchased today on the construction market. The main feature by which these products are classified is the material of manufacture. The choice of raw materials depends on the complexity of the future construction and its individual characteristics. Consider what raw materials are most often used to make molds for concrete.

Styrofoam. Many people are interested in the question of what is expanded polystyrene. This material is the standard raw material used in the production of fixed formwork. The second name of expanded polystyrene is gas-filled polystyrene. It is characterized by a number of positive qualities that determine the popularity of the use of forms made from it.

Useful information! Expanded polystyrene has rather high strength characteristics and provides reliable thermal insulation of concrete.

Arbolit. This material includes 2 main components: wood shavings and concrete. Separate elements of fixed formwork made of wood concrete are represented by blocks. They have empty gaps, which are reinforced and filled with mortar during installation. The advantage of this raw material is that it has high strength. The soundproofing qualities of wood concrete are also its strength. Of the minuses of this material used for the manufacture of formwork, low thermal insulation and high cost can be noted.

Fiberboard. This raw material, like the previous one, consists of 2 components. The first of these is wood chips, which provide the fibrous structure of the individual elements of such formwork. The second component is represented by an inorganic binder. The main advantage of such formwork is resistance to temperature fluctuations.

Schepotement. Such material is considered less popular than the above options for fixed formwork. The technology of installing wood chips has its own nuances. Of the advantages of this material, it is worth highlighting very good sound insulation and resistance to temperature fluctuations.

Economical option: non-removable foam formwork

Today, there is the possibility of installing fixed formwork from foam boards. This option is quite common, as it allows you to significantly save finances when building a house. Penoplex is a material used for insulation and has good strength characteristics. This allows it to be used as concrete molds.

Penoplex plates have dimensions of 60x100 cm. The dimensions of these products prevail over the parameters of standard structures made of expanded polystyrene. In order to install the formwork around the foam house, it is necessary to perform the correct calculation of the material. It is also important to understand that such products do not have their own locking elements. Thus, before purchasing the material, it is necessary to think over the system of fastening individual parts to each other.

The use of penoplex allows you to reduce financial costs to a minimum. This is especially felt when compared with the costs required to build a standard structure. Slab formwork on telescopic props, wall panels and the use of plywood will cost significantly more.

Useful information! A common option for organizing fixing parts is the use of special jumpers, which are equipped with threads along the edges. Such elements are made of reinforcement. The main thing to remember is that the installation of such jumpers is carried out between the foam slabs.

This embodiment of the design is less expensive, but at the same time more complex due to the selection of clamps. The price of fixed formwork made of expanded polystyrene is higher, but its installation does not require any extra steps. If necessary, you can purchase clamps for foam boards, which are used when installing a polystyrene foam structure.

Fixed formwork made of foam: varieties of structural details

Formwork elements can have a different design, which is determined by their operational purpose. To date, there are such options for these products made from polystyrene foam:

• panels;

• blocks (cast and prefabricated);
• frame systems.

Frame systems are double-circuit structures, between the walls of which there is an empty space. During installation, reinforcement is laid inside such a formwork and a solution is poured. If you make a section of a finished wall made using this technology, then it will be possible to distinguish three layers: two outer ones, represented by formwork, and the middle one made of reinforced concrete.

Foam blocks are divided into two large groups: cast and prefabricated. During the assembly of the formwork, these elements are aligned in such a way that they are located on top of each other. Moreover, no adhesive mixtures (for example, glue) are used for docking. The layout of the blocks is carried out in a checkerboard pattern.

Cast products are also called thermoblocks. This is due to the fact that they have a rather high density (up to 40 kg/m³). Structural features affect the thermal insulation characteristics. A block of this type consists of 2 sheets, which are joined together by means of special jumpers. The assembly of such parts and the connection of their individual elements are carried out at the manufacturing stage. It is worth noting that such structures have one drawback: they warm up rather poorly. This is due to the location of the insulation on the inside of the wall pie.

The sizes of blocks of molded foam formwork can be different. However, products with dimensions of 1000x250x250 mm are considered the standard option. The mass of such a block is usually about 1 kg. The thickness of the insulation located on both sides (outside) is 50 mm. Accordingly, the same indicator of the concrete layer will be 150 mm.

Insulation in the forms that are used to pour concrete can be different. The future design characteristics depend on the choice of insulator material. It is important to remember that such a layer traditionally performs two main functions. The first of them is shaping, and the second is heat-insulating. Depending on the type of blocks, the cost of polystyrene foam also varies. How much do different types of forms cost? Pricing takes place taking into account the design, as well as the thickness of the insulation layer.

Note! It is not recommended to carry out concreting in more than 3 rows. The ideal option would be to lay concrete in 2.5 rows, since in this case the seam will be located in the middle of the block.

Prefabricated Styrofoam Blocks for Formwork

The formwork can be represented by prefabricated elements, which differ from the cast ones in their structure and have some application features. Such blocks consist of two sheets, which are assembled into a single structure before the start of installation work. It is important to note that such elements can be made not only from expanded polystyrene, but also from other materials. The distance between sheets 1 and 2 remains unchanged due to special components called spacers.

Building a house from a fixed formwork of this type has several features that need to be focused on. The main difference between prefabricated forms is that their use allows the use of more than 3 layers in the walls. Moreover, the combination of materials in this case does not play a role, while buildings made using cast blocks require strict adherence to the sequence of materials. Insulation in such a situation will always be located outside.

A common solution is the wall pie, which includes two cladding layers of rigid sheet material. Insulating material (polystyrene foam) is laid close to the outer sheet of this type. The second layer in this situation is reinforced concrete.

The project of the house from fixed formwork is made in advance. It contains all the necessary data indicating the design features, dimensions and individual solutions in accordance with the situation.

It should be noted that such forms have one significant advantage over cast counterparts. It lies in the fact that, if necessary, you can change the width of the internal cavity into which the reinforcement is laid and the solution is poured. The change in this indicator is made through the use of spacers. If such a need arises, you can purchase longer fixing elements.

All costs must be indicated in the formwork estimate. The device, prices, dimensions of individual elements - all this is recommended to be noted in the preliminary wiring diagram.

Design features of prefabricated forms affect the degree of heating of the wall. The absence of foam allows you to increase this figure. If necessary, collapsible structures used for the construction of buildings can be made by hand.

Installation of formwork for strip foundation: installation features

The most popular type of foundation used in the self-construction of houses and other structures is tape. Before starting the organization of such a foundation, it is necessary to carry out appropriate preparatory work. These include project development and site preparation. In addition, it is necessary to mark the place allotted for the construction of the foundation.

The formwork for a strip foundation is not particularly difficult, but there are some nuances that you need to know and follow. For example, it is recommended to fill in layers. The process itself takes place as follows: the cavity in the block is filled with a concrete solution, after which it remains only to wait for it to solidify.

Useful information! The organization of reinforcement is not a prerequisite. It fits in the event that there is a need to increase the strength characteristics of the structure.

Reinforcement binding is performed inside block elements. It is not necessary to dismantle the expanded polystyrene, as it will act as a heat insulator. It is important to remember that before starting to pour the cement mortar, you will need to check the accuracy of the location of the blocks in the ditch.

If necessary, the fixed formwork for the expanded polystyrene foundation is strengthened with the help of additional elements. It is very important to achieve the correct geometry of the base. This technology has many advantages. When using non-removable blocks made of expanded polystyrene, the cost of organizing the foundation is reduced by at least a third.

Formwork for a monolithic foundation: self-installation steps

After organizing the foundation of the future structure, you can proceed with the installation of the formwork. This operation is conditionally divided into three stages: the installation of blocks, the knitting of reinforcement and the pouring of the solution. Each stage is carried out in accordance with building codes and regulations. During work, safety precautions must be observed. Let's consider each stage in more detail.

Installing blocks. First, the first row of the form is mounted, which will be used for pouring concrete. It should be noted that installation is carried out only on a waterproofed surface of the base. Formwork for the foundation of expanded polystyrene should be tightly fixed by means of reinforcement bars. These elements are the link between the base and the formwork itself.

Experts advise checking the accuracy of the work performed, as deviations from the original design dimensions are possible. The presence of outlets for partitions is also a very important point that you need to pay attention to. After organizing the first row, you can start laying the second. Block mounting technology involves a chess system in which each subsequent row is shifted relative to the previous one. As a result, the junction of the elements of the first row should fall in the middle of the block of the second strip.

Knitting reinforcement. The installation of a metal structure is one of the most important moments in the organization of any type of building cake. Reinforcement is used to strengthen foundations, walls, and monolithic ceilings. Formwork for the foundation, consisting of blocks that fit in rows, should be surrounded around the perimeter with bars located in a horizontal plane.

In order to simplify the installation of fittings, each block has special grooves that are located in the jumpers (internal). Horizontal bars are mounted in such a way that each subsequent element overlaps the previous one. Further, the rods are connected to each other, as well as to vertical elements using a special wire.

Note! Reinforcement allows not only to increase the strength of the structure, but also to reduce the pressure of cement on the form.

Solution pouring. Before you start pouring your own fixed formwork with your own hands, it is recommended to take care of laying communications inside the forming structure. The cement mortar used for forming the formwork must not contain foreign additives and impurities (for example, crushed stone). The operation itself is quite simple. The pouring is carried out step by step, and the height of the concrete layer should not exceed 1 m. This indicator corresponds to the dimensions of 3-4 fixed structural blocks.

The price of fixed formwork for the foundation is lower than the cost of standard analogues, which involve the use of plywood and boards. It is important to remember that the filled solution requires leveling. For these purposes, a special tool is used - a vibrator. In the absence of the necessary electrical equipment, you can use a conventional bayonet shovel.

Fixed formwork for walls: casting technology

Independent use of such a technique for casting walls requires an understanding of the technological process. Most often, this type of construction is used by non-professionals in the case of the construction of private one-story houses, as well as garage structures. The construction of formwork made of expanded polystyrene can be carried out alone. However, a few people will complete the installation of the walls much faster.

The advantage of using styrofoam molds is that they are light in weight. Thus, physical activity in this case is reduced to a minimum. Before starting construction, it is necessary to study the step-by-step algorithm of actions and the nuances that allow you to answer the question of how to make the formwork correctly.

Walls made using this method are recommended to be installed on a strip foundation. This base is best suited for construction using non-removable foam molds. It is important to remember that the use of cement mortar for pouring walls often imposes a certain limit on the number of rows of blocks. Experts advise having 4 rows of forms, and they must be securely connected to the base of the building through reinforcement.

Useful information! It is not recommended to immediately pour all the concrete. First, you should perform a partial pour and wait some time for the solution to shrink. As a rule, this procedure takes no more than 3-4 hours. Next, the cement mortar is added.

When erecting monolithic structures for casting walls, special forms are often used - shields. They are connected using special coupling bolts and form a gap into which concrete is poured. Such products can have different dimensions. For example, their maximum height is 3.3 m, and the width indicator ranges from 0.25 to 2.4 m. After the solution hardens, this structure is dismantled. The size of the formwork shield is selected depending on the individual characteristics of the structure being erected.

It is worth noting that another feature of the fixed formwork used for pouring walls is its instability. This is due to the fact that the concrete poured into the molds has a large mass. Thus, even blocks laid in 4 rows and equipped with fittings need a daily wait. This time is enough for the solution to settle and thicken.

When installing non-removable blocks made of expanded polystyrene, special attention must be paid to their docking. Individual structural elements must be connected with great care so that the surface of the first rows is as even as possible. Otherwise, when adding the next rows, the wall may collapse due to their skew.

An alternative to expanded polystyrene is plastic. Plastic formwork for monolithic construction is used when it is required to ensure good strength and rigidity of the structure. The advantage of such products is that they are highly wear resistant.

Facing work allows not only to give the wall, cast in the formwork, a complete look, but also to enhance its protective characteristics. Finishing is carried out on almost all types of structures. After pouring the wall, as a rule, there is no need to level it. This is due to the design of the forms. Thus, the need for applying a thick layer of plaster disappears.

Saving on the finishing of walls and other surfaces is not worth it, since the total cost of work is already reduced due to the use of polystyrene foam. The price of this material is much lower than the cost of traditional formwork options.

Most often, a special mesh is enough to finish the wall, which can be made of fiberglass or metal. Such a mesh is joined to the concrete surface using an adhesive composition, after which it is sealed with plaster or putty.

It is in this way that not only standard rectangular walls are processed, but also round columns. Formwork for such structures is most often made of plastic. There are also cardboard forms.

Note! In addition to the standard methods of finishing the outer surface of concrete, there are other equally popular options. For example, tiles and artificial stone are often used as cladding.

For interior wall decoration, as a rule, plasterboard material is used. GKL installation is carried out in two ways - using profile elements or glue. This cladding method is very popular not only because of its simplicity and efficiency, but also because this material provides good sound insulation.

Racks for organizing a fixed form of floors

The traditional option for organizing floors in monolithic or any other buildings involves the use of special telescopic (sliding) racks. These products are used to fix temporary flooring, which is made from moisture-resistant formwork plywood. This method is not convenient, as it requires a lot of time and quite a lot of physical exertion.

The rack, which performs the supporting role, consists of several structural elements. The lower part of the telescopic product is equipped with a tripod, which ensures the stability of the pipe. In turn, in the upper part there is a special nozzle, which is necessary to capture and hold the construction beam - the crossbar. All slab formwork props are divided into two categories depending on the location of the thread. Some of them are equipped with an open thread, while others are closed.

The pipe, which has a smaller cross section, is distinguished by the presence of special holes along its entire length. The pitch of the holes can be different - from 11 to 17.5 cm. The outer pipe is equipped with a support nut. As a result, when it becomes necessary to fix the rack at a certain level, a special earring is threaded through the holes in the pipes. This element has a support (nut), so it is held in position.

Telescopic formwork props can vary in length. This figure ranges from 1.7 to 4.5 m. They can withstand fairly large loads (up to 4 tons). It is worth noting that such support products are made of metal, so they are coated with special anti-corrosion compounds, since steel can rust.

Fixed formwork for slabs: features and specifications

Unlike the standard method, which involves the presence of support posts, the polystyrene formwork for floors has a completely different installation technology. As a basis for such a system, special matrices are used, which are made from dense and durable polystyrene foam.

Such matrices should be laid on load-bearing walls. The advantage of this method is that these elements have a small mass, so they do not require serious physical effort to install them.

Note! Before starting work, it is necessary to calculate the formwork of the ceiling.

Docking matrices with each other is quite simple. Each product is equipped with a tongue-and-groove system for connection. Thus, any person who does not have experience in this field can perform such an installation. Thanks to the tongue-and-groove system, it becomes possible to quickly organize a continuous flooring.

Such a formwork for a monolithic floor is capable of withstanding a layer of concrete up to 15 cm thick. As a rule, this value is quite enough to organize a reliable structure. Before proceeding with pouring concrete, it is necessary to place the reinforcement between the butt zones of the floor elements. The metal frame should be assembled into a continuous beam that occupies the entire width of the gap.

Then, on top of the matrices, it is required to place a reinforcing mesh. It is made of rods, the diameter of which is from 10 to 15 mm. Reinforcement is knitted in the traditional way - by means of a special wire.

The final stage of creating volumetric formwork of floors involves pouring concrete, after which you need to wait for it to harden. Thus, the organization of floors is carried out using polystyrene foam matrices. The result of this process is a durable structure that can withstand significant loads.

After the cement mortar has hardened, the formwork made of expanded polystyrene is not dismantled. It remains in the floor cake and from that moment begins to perform a heat-insulating function. This way of organizing the structure is more technologically advanced when compared with the traditional method, which takes into account the use of removable beams for the formwork of the slabs.

It is important to remember that the independent use of such technology requires an understanding of its nuances. The main thing is that even before starting work, you need to know that laying floor elements requires accuracy. Any design errors or misalignment of the blocks during their installation can lead to the collapse of the structure.

Fixed formwork: pricesin today's market

The cost of blocks is an important point that you should pay attention to. The price of building blocks, from which fixed formwork is made, is influenced by two key factors:

• density of expanded polystyrene;
• detail dimensions.

The price of fixed formwork for the foundation of expanded polystyrene must be taken into account in the construction estimate. When choosing individual elements of the forming structure, it is recommended to pay attention to their density. This indicator affects the resistance of the structure to pressure. The higher the density of the parts, the correspondingly higher loads they can withstand.

Note! Experts advise purchasing blocks whose density ranges from 25 to 35 kg / m³.

The average cost of a block made of expanded polystyrene is approximately 160 rubles. It is worth considering that this price corresponds to products with dimensions of 1500x250x250 mm, having a density index of 30 kg / m³. Structures with a length of 1.5 m have the function of adjustment due to the installation of jumpers of different sizes (15-25 cm). Products with a length of 1 m are cheaper - from 130 rubles. for 1 piece

If you plan to use standard construction technology, then it is recommended to study the cost of various materials. The price of telescopic racks depends on the features of their design and the manufacturer's company. Currently, these supporting elements can be purchased for 500-5000 rubles. It is not recommended to buy the cheapest materials and tools, as they often have low technical characteristics.

The support elements are used to hold the wooden structure, which is made from laminated plywood for formwork. The price of 1 sheet of such material varies from 600 to 3000 rubles.

Fixed forms are a good alternative to standard designs that are assembled from wood and plywood. Such formwork allows not only pouring concrete, but also serves as a reliable heat-insulating material. It is actively used in private construction, however, it requires the study of installation instructions and compliance with safety rules.

with the use of fixed formwork made of expanded polystyrene has become widespread relatively recently. The relevance of this method is determined by the high thermal insulation properties of the walls. No wonder one of the names of the technology is a thermal house.

Types of fixed formwork made of expanded polystyrene

There are two main types of fixed formwork made of expanded polystyrene: panel and block.

panel formwork

It refers to large-sized elements that can be 2-3 meters in length and height.

To connect the plates in the same plane, special brackets are used, and to connect opposite walls, fasteners in the form of metal or plastic ties are used. Most manufacturers produce panels with profiled ends - this provides a higher tightness of the joints.

This type of fixed formwork is more often used for pouring insulated foundations and plinths, as well as for monolithic walls in the construction of industrial facilities. Because of this, it is often called universal.

The advantage of the view is that you can change the distance between the walls of the formwork by adjusting the length of the tie.

The disadvantage is a more complex assembly and a simple ("rectilinear") geometry.

Block fixed formwork

More common is fixed formwork made of small blocks, which are two parallel small plates connected by ties. Formwork blocks can be one-piece or detachable. In the first case, the plates and ties of the block are made of expanded polystyrene in the form of a single hollow structure, in the second, the plates are assembled into a block using perforated plastic ties.

Two main types of block (angular and straight) make it possible to assemble a formwork of a simple shape. Door and window openings are made using end caps.

The use of shaped blocks (can be ordered according to an individual project) allows you to install formwork for a building of any geometry. The wider the range of block formwork, the more complex the architectural forms.

As a rule, the end connection of the blocks in the vertical plane is provided using the tongue-and-groove profile, and the docking of the blocks in the horizontal plane is made according to the principle of the Lego constructor.

Technology features

The technology for erecting panel formwork from expanded polystyrene plates, in principle, does not differ from the standard panel formwork. The only difference is that after the concrete has matured, the slabs are not dismantled, but left as a heater.

The technology of monolithic construction using block formwork differs from the usual one. In fact, at the first stage, it resembles the construction of a house from large-format building blocks - an orderly installation occurs with a displacement of vertical seams. The only difference is that vertical reinforcement should come out of the basement, on which the blocks are “planted”.

At the second stage, the pins protruding from the base are increased and knitted with horizontal rods, forming a reinforcing frame. The connection of the reinforcement to the frame occurs exclusively with the help of wire - welding is not recommended due to the flammability of polystyrene foam (despite the use of the self-extinguishing brand PSB-S).

Despite the "correct" geometry and the "clear" connection of the blocks, it is necessary to periodically monitor and adjust the levels.

After the assembly of the third row of block formwork, concrete is poured (according to the rules of monolithic construction - the entire volume at one time or in several, but without long breaks). The pouring is carried out until the middle of the third row, after which the laying of the next rows of block formwork begins.

Expanded polystyrene is a rather fragile material, it must be protected from mechanical damage, and the effect of ultraviolet radiation is also harmful to it. The outer part of the facade can be plastered, tiled or bricked. Internal walls are plastered, sheathed with wall panels or drywall.

Advantages and disadvantages

A high degree of thermal insulation and no need for additional insulation is not the only advantage of fixed formwork technology.

In fact, these are prefabricated sandwich panels "on the contrary" - the supporting rigid layer is in the middle. Therefore, when compared with an ordinary monolithic house with the same degree of thermal insulation, the following advantages can be given:

• reducing the thickness of the walls, which means reducing the load on the ground;
• savings on the zero cycle and foundation construction;
• reduction in the volume of concrete work;
• reduction of transport costs for the delivery of ready-made mortar or components for the production of concrete mix on site.

Another factor that reduces the time of work is just the "non-removable" formwork. Even in comparison with the technology of "sliding" formwork, the pace of construction is much higher.

The advantages include the low water absorption of expanded polystyrene - it will not absorb water from the concrete solution at the ripening stage (which is important for its proper hydration) and will not allow excess moisture to pass during operation.

Disadvantages common to all polymers:

• combustibility: the addition of fire retardants reduces the risk of fire and reduces the possibility of fire spread, but does not eliminate the release of toxic substances in a fire;
• low vapor permeability requires the mandatory arrangement of a well-thought-out ventilation system.

Other fixed formwork materials

Slabs and blocks made of composite materials based on cement and wood waste (plus other binders and additives) can be used as fixed formwork.

These include:

• chip-cement slabs and blocks;
• fibrolite;

Basically, this is a fixed panel formwork, which is mounted according to general rules.

As an exception, a system that has a building block format can be cited.

A common drawback of these materials is that they do not have such high thermal insulation properties as polystyrene foam.

To compensate for this shortcoming, some fixed formwork systems use the same polystyrene foam for insulation.

So, there are materials for the outer wall of the formwork made of chip-cement slabs with an expanded polystyrene slab glued on the inside. And in the internal voids of block systems, before pouring concrete, inserts of expanded polystyrene are inserted.

Wooden or brick houses rightfully have an army of fans. But with all the advantages, they have one very significant disadvantage - their construction cannot be called fast. For those who are thinking about building their own home, but do not have enough time left and cannot boast of great knowledge in construction, it remains to choose a monolithic way of building housing. The article will focus on houses made of fixed formwork.

In order to fill the foundation and walls of such a house, formwork is used. It can be removable (that is, dismantled after completion of work) or fixed. The second option remains in place after pouring and curing the mortar, and all external finishing work is carried out directly on top of the formwork.

House using fixed formwork technology

• Formwork is nothing more than a form. You can remember your childhood games in the sandbox or imagine the hostess pouring dough for cakes into special baking containers. Only unlike the above examples, the form will remain in place, becoming part of the walls or foundation.

Houses from fixed formwork photo

• Fixed formwork is assembled according to the principle of a children's designer from blocks of different composition. The principle of installation resembles brickwork. Structural elements have grooves or special lock-type connections.
• If necessary, fasten opposite blocks using screeds. Be sure to use vertical reinforcement, and in order for the structure to withstand the pressure exerted on it from the inside by the solution, pouring is carried out in series. In each of the visits, cement is filled with a height equal to three or four rows of blocks.
• Formwork elements are made from expanded polystyrene or some other materials that contribute to thermal insulation.

Advantages of using fixed formwork

• Monolithic structures are strong in themselves. The left formwork creates an additional frame that reinforces the walls of the future house.
• Monolithic walls less pressure on the base, therefore, when developing projects of houses from fixed formwork, you can calculate the option with an increase in the number of storeys of the house.
• Sound and heat insulation of the dwelling. Expanded polystyrene is an excellent material for warming residential premises, and its characteristics are complemented by the fact that it perfectly dampens sounds. The erection of fixed formwork is a kind of simultaneous work on insulation and soundproofing.
• Less time - less labor. You need to save money when building your own home wisely. Rent of expensive construction equipment will be deleted from the estimate of a monolithic house. And voluntary or hired workers will not be required much. The filling process is fast. This means that you will not have to overpay workers for the extra time spent at the facility.

• Space saving. There is never enough free space even inside private houses designed according to personal projects. Monolithic walls are thinner than brick ones, but they protect their owners from the cold just as well, and they save a lot of space inside.
• Continuing the conversation about savings, it must be said that fixed formwork will allow you not to overpay for heating during the further operation of the house.
• Durability. If the technology is followed to the smallest detail, then the walls formed by polystyrene blocks and concrete will last at least a century.
• Ease of finishing. The blocks create a good even surface of the walls, which allows them to be finished both from the side of the street and inside the house without effort and extra costs for leveling the bases.

What is fixed formwork

Styrofoam blocks for mounting fixed formwork

• These are hollow elements with walls of various thicknesses. The outer side of the material is much larger than the inner one - it will be she who will be responsible for keeping the heat in the house. The blocks themselves are strong enough to hold the poured solution, non-hygroscopic and affordable.
• Assembly in the form of brickwork adds strength to the structure, and reinforcement will add additional rigidity to the wall. Reinforcement bars located vertically are overlapped. It is important to choose its diameter correctly, as well as the brand of concrete.

• Communications, including electrical wiring, are laid through holes previously cut in the blocks. All work must be completed before pouring begins. The output is a kind of sandwich, where the “stuffing” of reinforced concrete is enclosed between layers of insulation.
• Opponents of expanded polystyrene emphasize that this material is not environmentally friendly. But it's more of a manufacturer's choice. Foamed polystyrene, manufactured according to all standards and rules, does not pose a threat to health. Suffice it to say that the captious European commissions and examinations allowed the use of this synthetic material in conjunction with food. Therefore, when purchasing material, it is worth familiarizing yourself with quality certificates and not chasing dubious monetary gain.
• But with the vapor permeability of expanded polystyrene, things are really bad. But there will be no problem if the ventilation system is well thought out.

• It is vapor permeable because it is based on cement. The blocks will have to be laid on a special glue, tied with reinforcement and then poured. In terms of strength, they are superior to the formwork made of expanded polystyrene.
• Cement-based blocks are also very diverse. So there are masonry blocks for load-bearing walls, produced in several sizes and modifications, you can separately purchase elements for formwork of columns, vertical or load-bearing beams of floors, lintels or strapping belts.

• This is an invention of the Dutch developers. They have been known since the 1930s. For their production, large coniferous wood chips are used (it makes up approximately 80-90% of the total composition of the material). Chips are treated with special additives and held together with a mixture of gypsum, cement clinker and some other additives (Portland cement).
• The advantages, in addition to environmental friendliness, are obvious:
  • high strength against the background of low weight;
  • vapor permeability;
  • heat and sound insulation properties;
  • weather resistance;
  • frost resistance.
• Fire safety is achieved through special processing, and such blocks are also not afraid of rotting, mold and pests. They are easy to cut and process. During the construction of the formwork, the plates are placed opposite each other and fastened with wire ties. They not only connect structural elements, but also do not allow the wall to deviate from the vertical. Material dimensions are standard: 2000 × 500 × 35 mm.
• They have also found another application: often wood chips - cement slabs are used to insulate facades or to build small panel houses in the country, designed for living in the summer.
• Reinforcing the structure will have to be less. Fortifications will require lintels for window and door openings, columns. And the walls themselves are reinforced with a significant gap of 2.5 or 3 meters (for formwork made of polystyrene foam blocks, the interval is 1 meter). In one approach, the mixture is poured, moving along the perimeter, to a height of a meter (two rows). The poured concrete is compacted by baying.
• Since the first version of the material for fixed formwork is much more common, it is worth considering the technology of erection from polystyrene foam blocks as an example.

Do-it-yourself construction of houses from fixed formwork

So, there is a foundation made in the most suitable way for this soil. Most often it is a tape base. In any case, it is first covered with a layer of waterproofing material, and reinforcing bars are driven in.

• The blocks are carefully strung on the reinforcement, fastened to each other in accordance with the manufacturer's recommendations (wire ties). Start with corner pieces. It is convenient to stretch a cord between them to refer to it when laying out the remaining blocks in a row. At the ends of the material there are ridges and grooves. This type of joint will hold all the formwork pieces in place. The first layer is the basis of the future building. At this stage, the laying of the bends of the internal partitions, openings of the entrance groups. All engineering communications are formed right there. The design feature of the blocks (internal voids) allows you to hide all the necessary wiring inside the walls. We must not forget about ventilation.

• The second row of blocks is stacked with an offset, like bricks. Such dressing will provide strength and rigidity of the structure. It is important to ensure that the sides of the stacked blocks match. Be sure to check the level so as not to take the wall away from the vertical. Fixing blocks of the first and second row is easy. The grooves on the surface of the elements are closed after light pressure.
• The laying of the third row of polystyrene blocks is carried out similarly to the installation of the second level.

• Concrete is poured along the perimeter of the site with the erected formwork. It is important to compact the poured mixture well. A small depth of filling with a mortar allows you to use a piece of reinforcement for these purposes: they act like a bayonet - they intensively pierce concrete to get rid of voids, destroying air bubbles. The optimal length is calculated as follows: the height of the block must be multiplied by 3. But the acquisition (or leasing) of a deep vibrator will contribute to the speedy completion of the work. It will cope with the task of compacting the solution much more efficiently. For this, the diameter of its working part should not exceed 4 cm.
• Experts advise not to fill the top layer of blocks with cement to the very end. If you fill half the last row, then the seam will turn out to be hidden inside the polystyrene foam formwork elements. This means that the wall will be stronger. For one m², it will be necessary to pour from 0.075 to 0.125 m³ of solution.

Masonry of the fourth and subsequent rows

• The laying of blocks in subsequent rows has the same algorithm that was described. After the sixth row takes its place, the operation of pouring concrete is repeated. Formwork of floors is best done with the support of specialists. The technology is like that. In the row of blocks where it is planned to lay floor beams (or floor logs), a recess of the required dimensions is made. The cut fragment should not exceed ¼ of the formwork element. Now the beams are installed in their places, and pouring is carried out.

• Finishing a house from fixed formwork is quite simple. Due to the high adhesion of the blocks to the plaster mixture, it will lie evenly and easily. Roofing in monolithic houses is no different from erecting a roof in buildings built using a different technology.

What can you make a fixed formwork for the foundation yourself?

If the home master has the strength to be accurate, accurate and consistent in his actions, then he will be able to make a fixed form for the foundation himself. You will need to choose from several options for a suitable material:

• waterproof plywood,
• cement particle board,
• flat slate.

All of them are quite durable, resistant to moisture, elastic. The only indicator that these materials do not have is thermal insulation. Therefore, in addition, you need to purchase something to provide heat (for example, mineral wool). You will also need waterproofing material, reinforcement, components for a cement-sand mixture, a set of coupling screws and nuts to fix the structural elements together.

The cost of building a house from fixed formwork

• The cost of a monolithic house made of fixed formwork is much lower than a brick or wooden housing option.
• The price of materials varies depending on the region and manufacturer, but on average, you will have to pay from 800 to 1000 rubles per m² of formwork from expanded polystyrene blocks.
• All manufacturers and sellers calculate the total cost of formwork for free, and there are calculators on official websites for accurate calculations.

Fixed formwork house: construction technology, Construction Portal

Construction of houses Wooden or brick houses rightfully have an army of fans. But with all the advantages, they have one very significant disadvantage - their construction is not quick