Foundation formwork: types, methods, materials. Formwork for monolithic walls How to make formwork for a strip foundation

The construction of a building begins with the foundation. To implement this design, you need to pour concrete into a pre-constructed frame, which is called formwork. It should be as rigid and strong as possible in order to prevent changes in the shape and size of the foundation tape. We will tell you what types of formwork for strip foundations exist, what material the structure is made of and how to properly install it.

What is strip foundation

The most important point in planning the construction of a house is the correct choice of the type of foundation - the main structural element of the building. An incorrectly designed foundation often causes irreparable consequences during the operation of the building.

The strip foundation is a reinforced concrete strip laid around the perimeter of the building. At the same time, the tape is laid under the outer and inner walls, which helps to maintain the shape of their cross section. The technology of the strip foundation device is not particularly complicated. However, compared with the columnar type, the construction of this structure requires more time and building material.

The scope of the strip foundation is quite extensive. It is often used:

• in the construction of buildings with concrete and brick walls with a high density index (more than 1300 kg / m3);
• for buildings with heavy floors (monolithic or prefabricated reinforced concrete);
• when building houses in areas with heterogeneous soil (for even distribution of the load on the walls);
• if the building is planned to equip the basement.

Design requirements

Formwork is a supporting structure that is poured with concrete to form the foundation. Therefore, its material and installation scheme must meet the following requirements:

• Strength. The formwork walls must withstand the pressure of the concrete. In this case, a slight uniform deformation is allowed along the entire perimeter of the building.
• The ability to withstand the temperature and humidity conditions, which is necessary for a thorough hardening of the solution. Formwork should be made of chemically neutral material.
• The absence of gaps between the formwork elements, chips and cracks in the material. In the case of leakage of the solution in the foundation, unwanted voids are formed.
• Compliance with the design dimensions of the calculated data.

Formwork types

When pouring a strip foundation, different types of formwork are used. They differ structurally, as well as the material from which they are made.

By design, formwork for a strip foundation can be:

• Removable. Before pouring the concrete mixture, the panels are assembled and installed, and after the mortar has hardened, they are dismantled;
• Fixed. Such formwork remains in the foundation structure, while serving as a heater;
• Combined, which is a combination of the two previous types. It is a removable structure with a heater laid inside, which, unlike the outer formwork, cannot be dismantled.

Often, removable formwork is used to fill a strip-type foundation, since this option is more economical. However, fixed and combined designs have recently begun to enjoy increasing popularity.

Material for manufacturing

If you decide to do the formwork with your own hands, the right choice would be to make a frame from lumber. The design in this case will be removable. Wood has sufficient strength, is easy to process, is an environmentally friendly material and is inexpensive. The use of metal or plastic does not make much sense, especially considering that the former is susceptible to corrosion, and the latter does not tolerate low temperatures.

The most popular lumber for assembling formwork for strip foundations is edged board. The product is preferred due to its precise dimensions, which can significantly reduce the amount of finishing work on finishing the concrete base. As a result, the foundation is obtained as even as possible. Accordingly, the cost of its construction is also reduced. In addition, due to the linear dimensions of the lumber, it is much easier to assemble the formwork with your own hands, including a set of boards with walls of the required height. In addition, the material can be used repeatedly, which makes it as convenient and cost-effective as possible.

Useful advice: Use boards unsuitable for assembling formwork for roofing or lining subfloors.

As for the type of wood for the manufacture of the frame for the foundation, it all depends on the expected load of the poured concrete solution. The most durable lumber is made from hardwoods. From such boards they make formwork for the foundation in both civil and industrial construction. If super-heavy loads are not expected, then you can use sawn timber from coniferous trees.

Territory preparation

Before proceeding to the construction of the foundation, engineering and geological surveys should be performed in order to determine the type of soil, as well as the depth of laying the future foundation. In this matter, it is better to consult with the employees of the capital construction department in your region. Be sure to find out the depth of freezing of the earth in your area and the depth of groundwater. So, the foundation should lie 0.3 m below the freezing depth and should not reach the level of groundwater.

In order for the foundation and the building itself to last for many years, the concrete base must be designed in accordance with all rules and regulations. Therefore, here it is advisable to use the services of a qualified specialist who will help to competently make the necessary calculations. Do not try to design a foundation yourself without basic knowledge in this area. This can cause unpleasant consequences, such as the formation of cracks in the walls, deformation of the base, and so on.

Before designing the foundation, it is necessary to determine the size of the building, the location and thickness of the internal and load-bearing walls using the heat engineering calculation of the building envelope. The fact is that the wider and heavier the walls, the more powerful the foundation itself should be. Having decided on these parameters, you can proceed to the foundation device, which begins with the marking of the territory.

Plot marking

First you need to clear the site of debris, remove the vegetation layer and level the surface. After that, two U-shaped structures are installed on the site, which are two pegs driven into the ground with a horizontal rail fixed to them. These structures, together with a rope stretched over them, mark the outer edge of one of the walls of the foundation. Next, a second rope with the same U-shaped design is pulled perpendicular to the first. Similarly, the marking of all other external boundaries of the concrete base is performed.

The next step involves the designation of the inner sides of the walls. The ropes should be pulled parallel to those that define the outer edges of the foundation. In this case, the distance between them should correspond to the width of the walls of the future base. After that, it is necessary to measure all corners - they must be straight. If initially it was not possible to make a perfect rectangle, then pull the ropes diagonally and achieve their equality. This way you will get all 90 degree angles.

Following the designation of the location of the main contour, the marking of the internal walls of the foundation is carried out, which will become the basis for the internal partitions of the building.

Excavation

The markup is ready and now you can start developing the soil. Trenches should be dug strictly along stretched ropes. As noted earlier, the depth of laying the foundation is selected depending on the depth of soil freezing. At the same time, the height of the trenches under the internal walls of a heated house does not depend on this parameter and is often 0.5 m.

It is worth noting a few nuances about the shape of the cross-section of the trench under the strip foundation. If the depth of laying the concrete base is less than 1 m, then the walls can be made vertical. In the case of a deeper excavation of the soil, the walls must be made with a slight slope.

If it is planned to build a cellar, then a foundation pit is dug for it at the same stage. To reduce the volume of excavation, it can be placed in any of the corners of the future building, along two walls of the foundation.

Helpful Hint: The best place to build a cellar will be the south side of the house.

Material calculation, necessary tools

When buying lumber for formwork, you need to remember that the boards will be located on both sides of the trench. In addition, the number of planks required also depends on the depth of the foundation and the width of the wooden product itself. After all, the boards are knocked down with bars into shields, the height of which should be slightly greater than the depth of the trench. Therefore, to determine the number of boards, it is necessary to measure the total length of the trench, multiply it by two, divide by the length of one wooden product and multiply by the ratio of the height of the trench to the width of the board. As for the bars, the step of their location should be no more than 40 cm. Depending on this, the number of required bars is also determined. So, for work you will need the following materials:

• board (humidity - no more than 22%; thickness - 25-50 mm; width - 200-300 mm);
• bars (section 40 * 40 mm; length is equal to the depth of the trench);
• sand;
• nails, screws;
• tow;
• thin rails.

For the installation of formwork for a strip foundation, you will need tools:

• hacksaw for wood, electric jigsaw or grinder;
• drill, hammer;
• yardstick;
• building level.

After completing the preparatory work and purchasing materials, we proceed to the installation of the formwork for the strip foundation. The procedure is as follows:

1. Sand cushion laying. Given that the weight of the concrete structure is very large, in order to evenly distribute it to the ground, a layer of sand must be laid. The height of the compacted and moistened pillow is 150 mm. On a flat and solid base, you can begin the installation of formwork.
2. Installation of guide boards. This procedure must be carried out strictly along the line, so stretch the fishing line along the entire length of the trench in advance. After that, install the guide boards according to the marking, fixing them with pegs and vertical bars from the inside. On the outside, in addition to the pegs, install additional stops. After that, check the correct installation of the guide elements using a tape measure and a building level.
3. Shield installation. We attach the boards to the bars and connect them with nails. The procedure is performed from the bottom up.
4. After assembling the shields, we put spacers. As the latter, bars can also be used. As a result of the installation of spacers, the panels should take their final position, that is, the formwork will take the form of the walls of the future foundation.

Properly executed formwork for the strip foundation is the key to the strength and durability of the building

Important: To seal the resulting cracks, use tow or thin slats.

This completes the procedure for installing the formwork under the strip foundation. But there are a few more nuances that should be performed if necessary.

The nuances of work

• If the height of the formwork exceeds one and a half meters, then at the bottom of the trench it is necessary to make a window to remove industrial waste, which in this case can be very large.
• A layer of waterproofing material is laid at the last stage of the formwork installation, before reinforcement.
• If re-use of a collapsible structure is intended, then an oily substance should be applied to its inner surface to minimize adhesion to concrete.

The right strip foundation for the house

Remember, well-executed formwork is a guarantee of ensuring the correct form of the concrete base of the building. Therefore, take this work with all seriousness and follow the technology of erecting a frame under a strip foundation.

We make formwork for a strip foundation with our own hands - the necessary material, calculation, device, etc. with video

Types of formwork for strip foundations. The choice of material, preparatory work and the device of a wooden structure.

The formwork serves as an element of the fence when pouring concrete, preventing it from flowing out of the future structure and thus giving it the necessary shape. This device is used for the manufacture of foundations of various types. The most common application is the formation of formwork for strip foundations. With the help of formwork, reinforced belts are made for floor slabs or the roof frame of the building, as well as many other structures that involve pouring the form with concrete or cement mortar. The material for the foundation formwork can be used differently, and in our article we will consider several options.

Wooden formwork with waterproofing coating Source demidovo52.ru

Types and materials for the manufacture of formwork

Depending on the desired quality of the concrete structure, the speed of its construction and the possibility of reusing the enclosing material, the following types of formwork are distinguished:

• Removable (collapsible). It implies the repeated use of functional parts of the device. It is dismantled after hardening of reinforced concrete.
• Fixed. It remains in the foundation, while serving as an additional protective or decorative element of the structure.
• Wooden. It is used in collapsible structures. As the main enclosing material, edged wooden boards of various sections, plywood, OSB boards, and in rare cases chipboard are used.
• metal. Enclosing elements in such formwork are made of sheet metal. The nodes that provide rigidity and prevent deformation of the planes can be made of wood or a metal profile.
• Polymer. It can be either removable or non-removable. In the first case, it implies the use of special plastic sheets as a fence. In the second, concrete is poured into polystyrene molds, assembled by means of locks into a one-piece structure.

Formwork for reusable use - often these are rented Source stroiecoplast.ru

Overview of standard formwork: types and conditions for the use of formwork structures

Depending on the requirements for the reinforced concrete structure, the type of formwork is selected. The dimensions of the foundation, namely its height and width, are of paramount importance. The higher the structure, the stronger the enclosing material should be.

Collapsible formwork

This is the most common version of the formwork for strip foundations and not only. Its popularity is due to ease of manufacture, availability of material and low cost compared to other options.

Most often, such formwork is built from OSB, boards from wooden boards, plywood, and sometimes chipboard. As a material for the frame, a wooden beam of a suitable section or a metal profile is used. All material after dismantling the formwork can be used in further construction work. Naturally, this is possible with a careful attitude to it.

Even disposable formwork can be collapsible, and the boards are quite suitable for a subfloor or similar work. Source readmehouse.ru

From the boards

For the construction of formwork, you will need a board with a thickness of 25 mm or more, if the width of the foundation is up to 300 mm. A larger design with a tape width of 400 mm and above will require the use of a 40-50 mm board. Lumber of any breed, both hardwood and softwood, is suitable. It is most economically feasible to use spruce or pine. In addition, these rocks have sufficient strength and resistance to moisture changes.

Flaws: a long time for the assembly of panels and the subsequent installation / dismantling of building elements; The structure needs additional reinforcement.

Advantages: low cost.

From plywood, chipboard, OSB

In order for the OSB formwork for the foundation, or from plywood and chipboard, to be strong, you cannot do without a wooden beam, which will be necessary when assembling the frame and stops with braces. The recommended plate thickness is 18 mm or more. The thicker the plate, the less timber for rigidity will have to be added. Sheets size:

• waterproof plywood - 1200 * 2400;
• construction plywood - 1500 * 1500;
• OSB: 2500*1250;
• Chipboard - 3750 * 1750.

For a single use, you can use ordinary plywood, OSB boards or even chipboard (then you will have to throw it away). If many pouring cycles are planned, you should pay attention to laminated waterproof plywood.

Source derevyanny.com

On our website you can find contacts of construction companies that offer foundation repair and design services. You can directly communicate with representatives by visiting the exhibition of houses "Low-Rise Country".

Positive traits: simplicity and speed of assembly compared to all other collapsible options. When using cheap varieties of slabs, the cost of such formwork for the foundation will be lower than that of wood.

Flaws: high cost of waterproof laminated plywood; one-time use of inexpensive board materials.

Metal formwork

An expensive but practical option that can provide a high quality surface, which reduces the cost of its subsequent grinding (if any). Such designs are more often factory-made, therefore, they are most adapted for quick assembly. They have significant rigidity and the same significant mass, which implies the involvement of a team of builders for installation and, possibly, lifting equipment. There are lightweight options made of aluminum or its alloys, but it is not practical to use them to save on the wages of workers and cranes.

The metal formwork for the foundation (photo below) is designed for reusable use and has significant potential in this regard, which partly justifies its high cost.

Reusable metal formwork Source stroyday.ru

The quality of the foundation made using iron formwork is an order of magnitude higher than the wooden options. This is due to the properties of the metal, which, unlike wood, does not absorb moisture and thus provides favorable conditions for the curing of concrete.

Polymer boards

The meaning is the same as with plywood, OSB or chipboard, with the only difference being that a polymer board is used as the fencing material, the size and thickness of which depends on the required rigidity. To ensure proper rigidity of the structure, a frame made of timber or a metal profile is required.

Polymer formwork is an expensive pleasure, but they are indispensable in the construction of standard structures. Source stroykarecept.ru

Fixed design

When choosing a material for non-separable formwork, one should choose one that will give the monolithic structure the necessary properties. For example, if insulation is subsequently required, it is better to use expanded polystyrene than concrete blocks or metal sheets.

Source pogreb-podval.ru

Styrofoam blocks

A very simple and quick option, in addition, the finished concrete structure is already insulated. The production of strip foundation formwork from blocks evokes an association with a constructor: lightweight blocks of high density polystyrene are assembled using locks located on the adjacent sides of the product. The technology provides for the presence of linear, angular, radius and other elements for the implementation of any geometric shapes and solutions.

There is also an option where dense polystyrene sheets are used as a bounding material. The joining of the sheets to each other is implemented using a simple tongue/groove connection. Opposite walls are connected by special metal brackets, which in parallel determine the width of the foundation tape.

The material has a small mass and is easy to handle, so the structures made of it are mounted quickly, do not require special equipment and skills.

Fixed formwork also works as a heater. Source gmk.spb.ru

Reinforced concrete foundation blocks

The name speaks for itself. Structurally, it resembles a formwork made of expanded polystyrene. The difference is in the absence of insulation, significant mass and greater rigidity of the finished monolithic structure. In the case of work with large-sized blocks, a team of builders and lifting equipment will be needed for mounting.

Source domsovetov.by

Auxiliary materials and necessary tools

In the process of mounting the formwork for the strip foundation, you have to use various devices. Most often they are needed in the case of the manufacture of wooden structures, especially when scrap sheet material is used. Factory products are usually equipped with everything you need.

metal studs

Needed for tall buildings. It is not possible to provide high-quality fixation of the thickness of the tape over the entire area of ​​​​the fence in other ways. Studs are not needed for structures less than half a meter high, especially if sufficiently rigid sheet materials or boards are used.

The purpose of this element is to prevent bursting of the formwork walls. For proper functioning, the stud is installed in a plastic pipe. This is done in such a way that when tightening, the walls of the fence from the inside rest against the pipe. From the outside, it is recommended to wear washers on the stud.

Braces

Designed to prevent the walls of the fence from bending outward. They are made from wooden blocks of different lengths. The entrance is all suitable material, including trimmings.

Source plotnikov-pub.ru

Polyethylene film

Prevents the concrete mix from flowing out of the formwork. It is mainly used for structures made of boards, including unedged ones. Helps prevent excessive contamination of wood with cement mortar, which gives more opportunities for their subsequent use.

Production of removable formwork for strip foundation

There are a lot of options for the construction of such structures and the choice of the most suitable one depends on the situation and the preferences of specialists. Consider how formwork is made for a strip foundation using wooden shields and timber.

Technology for the manufacture of wooden shields

The thickness of the board is selected depending on the width of the tape and the height of the structure. With a width of up to 300 mm and a height of up to 1 m, a board of 25-30 mm can be used. The length of the shields also depends on the dimensions of the fence and the geometry of the structure. Considering the standard length of the board (4.5 - 6 m), the shield length of 2 - 2.5 m can be considered optimal.

In the manufacture of fasteners, it is better to use nails. This will greatly facilitate dismantling, save money and speed up the process.

Source kakpostroit.su

For shields up to 1 meter high, the assembly represents the following sequence of actions:

• It is necessary to prepare boards for a set of one shield, for example, 10 boards 2 m long, 100 mm wide;
• To ensure rigidity and bonding of boards, you can use a beam with a section of 50 * 50, - 4 pieces per shield;
• The board is nailed to the beam, which is located at regular intervals, while there should be a distance of about 200 mm along the edges of the ends (in order to tie the shields together during installation). The bars should be made somewhat longer so that they can be driven into the ground, if this is provided for by the design.
• For tall structures with a tape width of 400 mm or more, a board with a thickness of 40 - 50 mm should be used, a bar for the frame - at least 100 * 50 mm.

Installation work

First you need to make a markup. After that, the shields are located along the foundation tape. From the outside, the tapes are fixed with braces, from the inside, stops or studs are installed. During work, it is necessary to control the level in all planes and the geometric accuracy of the structure.

Video description

Visually about the formwork for the foundation, see the video:

Assembly of fixed formwork

The construction of polystyrene blocks is assembled gradually - as the height of the foundation or walls increases. The first row is laid out on a prepared base - a pillow, having previously laid waterproofing with entry to the walls of the trench (in the case of a trench option). The assembly is made in locks on the faces of the blocks.

The height is gained, at which it is possible to tie the reinforcement without significant difficulties. In the case of using polymer sheets, the walls are fixed together with brackets that come with the kit. Having typed several rows and unleashed the reinforcement, concrete is poured, after which the following rows are assembled, and so on until the structure is completely ready.

For non-separable concrete block formwork, the process is the same. The difference is in the design of the material and the method of decoupling the reinforcement, which fits into specially provided recesses on the upper and lower surfaces of the blocks. The installation process also occurs gradually - after pouring one or two rows, the following are mounted.

Video description

See more about fixed formwork in the video:

Results

The use of this or that formwork largely depends on the costs that the developer is ready to go to, as well as the requirements for the quality of the foundation. For budget options, wood formwork using improvised means is quite suitable (there are examples using cardboard boxes). If speed is important, and quality will have to consider other options that will require a lot of money.

There are several ways to level the formwork. The rules for the work are reflected in the specialized documentation: SNiP 3.01.03-84 "Geodetic works in construction" and SNiP 2.03.01-84 "Concrete and reinforced concrete structures".

In most cases, individual developers have no time to study the rules and regulations. Therefore, the recommendations of builders based on the requirements of SNiP and optimized for different conditions for performing concrete pouring are the most useful.

Formwork material selection

The formwork is a frame, the cavity of which is poured with concrete. After its setting, the auxiliary structure is dismantled (removable formwork) or it remains in its original place and will be an integral part of the structure being erected (fixed).

The first option uses new sheet materials intended for other purposes. But in this case, the inner walls of the frame are covered with overlapped sheets of dense polyethylene film, which is fixed to the shields with staples and a construction stapler. This precaution will protect the materials from contamination with cement-sand mortar.

For formwork, you can use:

• Edged or unedged boards;
• Sheets of plywood or OSB;
• Cement particle boards (DSP);
• Styrofoam with a thickness of at least 5 cm;
• Cement slabs (fibrolite);
• Metal sheets with a thickness of 2 mm;
• High strength plastic sheets.

How to make shields

When pouring the foundation, you may encounter such a problem as bursting the formwork. This problem occurs for two reasons:

• Wrong material selected;
• Incorrectly assembled and installed frame panels for concreting.

In order to make a solid formwork from edged boards, lumber with a section of 100 × 25 mm and 150 × 30 mm is used. The shields will need to be supported with bars with a section of 100 × 50 mm. It is also used for the installation of vertical formwork racks, located in increments of 80-100 cm. The installation of panels consists of several stages.

Install vertical racks from a bar 100 × 50 mm.

The inner walls are sewn up with boards from 2.5 cm thick using wood screws.

The mounted panels are supported with bars installed on the outside of the formwork. The step between the supports is 60-70 cm. This design will withstand the pressure of concrete. After the foundation is poured and gains brand strength, the wooden frame is dismantled, and the lumber is used for other purposes. For example, for framing a truss system or a ventilated facade.

With a shield height of 90 cm and mechanized concrete pouring (from a concrete pump), the pressure per 1 linear meter of the frame will be at least 2300 kgf / p. m. The formwork may not withstand and deform. Therefore, its walls must be tightened with metal studs fixed on the outer sides of the frame with nuts.

Site preparation

It is possible to set the formwork evenly only in advance. This stage of work is called "planning" and is carried out manually using shovels and improvised devices. It consists in leveling the site by moving the soil from higher places and filling it with recesses in the marking area.

Installation begins with the installation of vertical supports. The frame is erected inside a trench under a strip foundation or a pit under a slab foundation.

The bottom of the recesses must be leveled and compacted. On it, it is necessary to first form a depreciation "cushion", consisting of two layers: sand and gravel. Each layer also needs to be leveled and compacted. After that, proceed to the installation of the frame as described above.

alignment

An important point in the construction of formwork is its leveling. Recommendation from builders: no need to strive to align the upper planes of the frame "under zero". On the contrary, it is better to make the formwork walls several centimeters higher than the planned foundation height. And on the inside of the shields, mark with a marker, drawing horizontal lines corresponding to the required plane of the foundation to be poured.

The main difficulty lies in drawing these lines correctly. It is not difficult to pour and level concrete over them. To accomplish this task, you can use the water level.

First, find the desired height of the foundation at the lowest marking point. Apply a water level flask to it, remember or mark the water level with a risk. Then, with the help of the second flask, the corresponding marks are placed on the remaining pegs. Draw lines and, if necessary, duplicate them with a thin wire.

There is another point of view on alignment: the walls of the frame must be aligned "at zero". For this purpose, at the marking stage, the height of the foundation is determined in the manner indicated above, and ropes or fishing line are pulled at this level. Shields are mounted, focusing on these devices.

The second way to align the walls of the formwork is to cut the shields along the lines drawn along the fishing line or rope. During pouring, the concrete is compacted with a reinforcement bar and leveled with a rule, which in this case should rest on the formwork walls.

How to use the laser level

This tool is useful for most marking, installation and finishing work.

The principle of the level is simple: it shows a perfectly even horizontal line due to the self-leveling mechanism inside the device.

Watch additional video:

The correct use of the level is to follow a few simple recommendations:

• Preliminarily eliminate all obstacles on the path of the laser line;
• It is not recommended to exceed the optimal distance from the level to the object specified in the instructions for the device;
• The instrument must be placed on a level surface or on a tripod;
• If there is no self-leveling function, before starting work, adjust the level using the built-in bubble level.

The construction of any monolithic objects, whether it is a residential building or an industrial building, is not complete without wall formwork. This design is necessary for the construction of walls and ceilings.

Manufacturers offer many variations to solve problems of any complexity, one of the most popular is the formwork of the Gamma series.

Formwork material

An important characteristic is the material from which the wall formwork is made. The calculation of the required amount of concrete depends on this, as well as its weight, strength, cost, installation and finishing. Formwork is made from:

reinforced concrete;

Each of the materials has its own advantages and disadvantages. Metal formwork is widely used in industrial construction (withstands high pouring speed). However, it is very heavy, its installation requires the use of special equipment.

The form of expanded polystyrene is light, it serves as an additional insulating layer. However, the low strength of the material complicates construction (for example, a concrete pump cannot be used for pouring).

Wood, chipboard and plywood are also easily deformed, but at the same time they provide easy and quick installation. Plastic is sensitive to negative temperatures, but durable and sealed. The main area of ​​​​use is private construction (if you need to make a shallow foundation or a light building with your own hands), because. their installation does not require special skills.

Large developers prefer to work using removable structures, which also include Gamma formwork. Depending on the purpose, it can be used to build:

round structures (columns, pillars);

floors.

The calculation of the required volume of concrete is carried out taking into account the type of formwork.

Advantages of removable structures

If we are not talking about one-time construction, prefabricated large-panel or panel formwork is the best option, due to the following advantages:

Versatility. Components (special fasteners, rotary elements) allow you to create structures that are complex in shape.

1. Installation of removable formwork

   The main components are the block and fastening elements (). Depending on the type of construction (panelboard, large-panelboard), the block can be sized from 90*60 cm to 330*120 cm. The calculation of the required size of the boards is based on the scale of construction. For the construction of a small house, or the usual panel formwork with blocks of 1.5 * 1 m is the best option.

   Panel formwork is easy to assemble with your own hands, installation does not require the use of special equipment, and various components allow you to assemble a structure of any shape. This makes it indispensable for pouring the foundation or erecting walls and floors of a one-two-story building.

   The frame of the shield is made of a metal profile (high-carbon steel or aluminum alloy). The shield is made of plastic or plywood, in some cases it is provided with a reinforcing material. Installation of additional stiffeners guarantees the strength of the structure.

   A significant advantage of the fixed form is its cost and easy installation. The construction of monolithic houses with this design minimizes labor costs. Whether the installation of other structures consists of the following steps:

   • a corner block is mounted and walls are erected;
   • installation of door and window openings;
   • concreting is carried out (each stage of pouring is performed after the previous layer has solidified).

   Features of large-panel formwork

   Large-panel formwork Gamma has, in addition to the listed elements, the following components:

   

   inside corner to make a corner block;

   hinged shields, with the help of which it is possible to form internal and external corners of any radius;

   arc-forming element, to obtain a rounded section of a wall or ceiling;

   ties that rigidly fix the shields to each other.

   Also, to facilitate work at height, the kit can be supplied with scaffolds for workers, which are easily attached to the block at the level of any floor. Components can be purchased as needed, the calculation of the required quantity will be done by specialists.

   Large-panel formwork is used in the construction of large-scale facilities, therefore, special requirements are imposed on it. The block must withstand high pouring speed, and its rigidity must ensure the ideal geometry of the walls and foundation. This is achieved through the following design features:

   shield made of solid-rolled profile;

   a special lock that allows inserting additional sheets up to 10 cm thick between the shields (to strengthen the structure or additional thermal and waterproofing);

   fastener elements simultaneously tighten and fasten the shields to each other;

   the block is covered with a special, protective coating (powder paint), such an external finish helps prevent corrosion.

   To date, adjustable removable formwork Gamma is the most optimal solution in terms of price-quality ratio.

   Application of wall formwork (video)

   The choice of formwork for various objects

   They are mainly used in the construction of the foundation of small objects (cottage, garage) with their own hands. Installation in a trench and pouring are carried out manually. For heavy structures, the foundation and walls are strengthened by reinforcement. Exterior and exterior finishing is possible immediately after the concrete has hardened.

   Fixed EPS formwork has become a popular solution for the construction of small private houses. The thermal insulation properties of expanded polystyrene can significantly save the cost of heating the room. In addition, the decoration of such a building (both inside and outside) is not particularly difficult. Most finishing materials (drywall, facing boards, lining, veneer) are easily attached to expanded polystyrene sheets.

   Removable panel formwork can be installed to build a shallow strip foundation, in which case it acts as a basement. Wooden or - the best solution for the price, since a shallow foundation does not imply the use of complex structures. It is easy to assemble and disassemble with your own hands, using improvised tools.

   Large-panel formwork (for example, Gamma 330) is used in the construction of multi-storey buildings, industrial facilities, etc. At the same time, due to its configuration, it is easily transformed into a form for floors, supporting elements. The accompanying documentation indicates possible assembly schemes and the calculation of the necessary elements.

One of the first stages in the construction of structures for various purposes is the installation of formwork. Often this process goes unnoticed. But already at the stage of preparation for pouring, it becomes clear that not everything is as simple as it was thought at first. Assemble the frame will help installation instructions formwork.

Formwork types

There are three types of construction:

• Removable, which is dismantled after the solution has completely dried. Such a formwork is assembled from separate parts. The result is a collapsible structure that can be dismantled and reused. Among the advantages of this type of formwork are ease of installation, the possibility of reuse, which significantly reduces the financial costs of construction.

• Fixed, respectively, one that is not dismantled. Installation of formwork of this type is carried out mainly from expanded polystyrene or polystyrene. It remains part of the structure under construction. And at the same time it acts as a heater.

• "Floating" formwork is typical for the construction of a monolithic foundation, which is immersed in the ground. It is a shield assembled from boards, which is slightly higher in height than the planned concrete structure. The shield is lowered into the pit and attached to its walls. Cardboard or roofing material is rolled on top of it.

There are also several types depending on the purpose:

• Wall formwork. Its installation is performed for the construction of vertical structures and walls.

• Horizontal, which is used for mounting the foundation and floors.

• Curved, which allows you to fill in details of unusual shapes.

Mounting and dismantling of formwork of each type has its own characteristics. You need to know them to get the job done right.

Advantages of fixed formwork

Installation of fixed formwork involves the purchase of a ready-made set for the work. It remains only to assemble the structure and install it. This implies a number of advantages that formwork of this type has:

• short terms of performance of works;

• ease of installation;

• low weight of the structure;

• resistance to the appearance of fungus and mold;

• fire safety;

• small cost.

Also, fixed formwork is at the same time a layer of insulation and is a foam blocks that are easily connected to each other. The inner wall is thinner than the outer one. Thanks to this, a high level of thermal insulation is achieved.

Construction of fixed formwork

Finished shields are attached to the corner bars with self-tapping screws or nails. Fastening must be secure. When the concrete expands, the pressure on the shield will increase, which can lead to cracking of the boards. The main thing is that the bar itself remains on the outside. Parallel to the assembled structure, another row is assembled at a distance of the future wall. As a result, you should get a frame around the entire perimeter.

A layer of crushed stone or sand is poured into the finished formwork box. This will protect the solution from moisture loss, which will go into the ground. Formwork installation technology provides protection against the flow of mortar through the existing holes. To do this, the shields are covered with a film or roofing felt, which are fastened with screws or staples using a stapler.

All work must be carried out taking into account the level. It is very important. At each stage, the evenness of the structure in height, length and vertical is checked (especially important). Two rows of shields must run strictly parallel to each other.

The main elements of the formwork

Removable formwork, which is assembled independently, consists of the following elements:

• The deck, which is a flat shield, is the enclosure of the entire form. The structure must be strong enough to withstand the pressure of the solution. Therefore, it is made of plywood or edged boards 4-5 cm thick.

• Scaffolding that is the support of the structure. They hold the walls, preventing the solution from squeezing out the deck. Scaffolding is made from pine bars or boards (2.5-5 cm).

• Fasteners are all the details with which all structural elements are twisted: wire, clamps, ties, hardware, and so on.

The deck is most often assembled from boards 15 cm wide, which are connected in several rows using nails (driven in from the inside, bent from the outside) or self-tapping screws (they are twisted from the inside). The distance between the boards should not exceed 3 mm. Shields are fastened together with additional slats.

A simpler deck manufacturing option is to use moisture-resistant plywood 1.8-2.1 cm thick.

Formwork installation

The frame will be installed evenly and level if the site is properly prepared in advance. It is marked with the help of cords stretched between the pegs. The sand cushion is filled up and compacted. If necessary, a pit is prepared.

Formwork installation takes place in the following sequence:

• The perimeter should be marked with vertical guides (wooden bars, metal corners or pipes).

• It is required to place ready-made shields along the guides, maintaining the required distance between them (it is equal to the required thickness of the foundation).

• Firmly fix the deck. Support it from the outside with inclined bars (1 brace for each meter of deck).

• Connect the shields to each other with 5x5 cm bars.

• Cover the inner side of the formwork with a film (roofing material).

Foundations up to 20 cm high do not require serious construction. For them, bars driven into the ground are enough.

Installation of wall formwork

More difficult is the process of erecting wall formwork. At the same time, small-panel and large-panel formwork are distinguished.

The first option is suitable for the construction of small buildings (country houses, utility buildings) and partitions between rooms. In this case, small-sized plywood shields are used.

The installation of large-panel formwork is typical for the construction of buildings with a large height. For work, use sheets of metal or large sheets of plywood.

For the installation of walls, a foundation is prepared, into which reinforcement is stuck. A two-row formwork frame is assembled around it. When using ordinary plywood, the joints are coated with glue or sealant. Currently, there is a special formwork plywood on the market. Its individual sheets are connected according to the tenon-groove principle, which does not require additional sealing.

Types of floors

The installation of the ceiling formwork depends on the type of ceiling itself. There are the following types of structures:

• On big bowls. It is used for structures with high height. In this case, vertical racks, jacks, inserts, crossbars and other elements are used to connect individual parts.

• On blade scaffolding, which is used for multi-storey buildings. Scaffolding is installed instead of plywood boards.

• On scaffolding of cup type. This view provides for the installation of the frame. Racks are interconnected by the cup method.

• On telescopic bowls. Suitable in cases where the ceiling height is less than 4.6 m. It is based on tripods that support the entire structure. From above boards from moisture resistant plywood keep within.

Formwork for overlapping

Currently, monolithic overlap is most often used. Using his example, we will analyze the process of mounting the formwork.

For formwork, vertical racks are used, interconnected by crossbars. They are attached at right angles to the bars running in the transverse direction. A plywood shield is laid on these transverse bars, which is the bottom of the formwork.

To perform these works, the following materials are used:

• stand - timber with a cross section of 12-15 cm;

• crossbar and cross beam - edged board 16-18 cm wide and 5 cm thick;

• braces - a board 3 cm thick;

• flooring - moisture resistant 1.8 cm thick.

Before starting work, it is necessary to carry out accurate calculations. It is important to determine the required number of racks, the step of their placement and other indicators.

Slab Formwork Assembly Instructions

The work instruction includes the following steps:

• Longitudinal bars are attached to the upper part of the racks, the second end of which is fixed on the wall.

• The second row is assembled in the same way. To do this, a board 5 cm thick is laid under the supports.

• Cross bars are laid in increments of 60 cm.

• Install support racks (strictly vertically).

• Racks are interconnected by braces.

• Sheets of plywood are laid on the transverse bars, leaving no gaps.

• The ends of the overlap are protected by masonry of blocks or bricks.

• The frame is assembled from reinforcement. At the same time, they leave, if necessary, space for communications.

When all work is completed, concrete can be poured. The formwork is removed after 3 weeks.

Conclusion

Installation of formwork of each type involves the use of certain materials. If boards are used, they must be new. Rotten old boards can not withstand the load and break. Plywood must be moisture resistant or laminated.

All work must be carried out in accordance with the calculations made. This is especially important for the installation of formwork for floors and walls.

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