DIY foundation shields. DIY foundation: simple solutions for formwork installation

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

What is a strip foundation

The most important point when planning the construction of a house is right choice type of foundation - the main structural element of the building. An improperly designed base often becomes the cause of irreparable consequences during the operation of a building.

The strip foundation is a reinforced concrete strip laid along the perimeter of the building. In this case, the tape is laid under the outer and interior walls, which contributes to the preservation of the shape of their cross-section. The technology of the strip foundation device is not particularly complex. However, in comparison with the columnar type, it takes more time and building material to erect this structure.

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

when erecting 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 on areas with heterogeneous soil (to evenly distribute the load on the walls);
if a basement is planned in the building.

Construction requirements

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

Strength. The walls of the formwork 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 temperature and humidity conditions, which is necessary for the thorough hardening of the solution. Formwork should be made of chemically neutral material.
Absence of gaps between formwork elements, chips and cracks in the material. If the mortar leaks out, unwanted voids will form in the foundation.
Correspondence of the dimensions of the structure to the calculated data.

Formwork types

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

By design, the formwork for the strip foundation can be:

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

Often, removable formwork is used to pour a strip-type foundation, since this option is more economical. However, fixed and combined designs have recently become more and more popular.

Material for making

If you decide to do the formwork yourself, making a frame from lumber is the right choice. In this case, the structure will be removable. Wood has sufficient strength, is easy to handle, is an environmentally friendly material and is inexpensive. The use of metal or plastic does not make much sense, especially if you consider that the former is prone to corrosion, and the latter does not tolerate low temperatures.

The most popular lumber for assembling formwork for a strip foundation is edged board... The product is preferred because of its precise dimensions, which can significantly reduce the amount of finishing work on the finishing of the concrete base. As a result, the foundation is as flat 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 the walls of the required height. In addition, the material can be used repeatedly, which makes it as convenient and cost effective as possible.

Helpful hint: Use boards that are not suitable for formwork assembly for the installation of lathing under the roof or paving of subfloors.

As for the type of wood for the manufacture of a frame for a foundation, it all depends on the expected load of the poured concrete mortar... The most durable lumber is made from hardwood. From such boards, formwork is made for the foundation in both civil and industrial construction. If super-large loads are not expected, then coniferous sawn timber can be used.

Site 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 staff of the capital construction department of your region. Be sure to find out the depth of freezing of the earth in your area and the depth of occurrence groundwater... So, the foundation should lie 0.3 m below the freezing depth and should not reach the groundwater level.

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

Before designing the foundation, you need to decide on the size of the building, the location and thickness of the internal ones, as well as load-bearing walls with the help of thermal engineering calculation of enclosing structures. 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.

Site marking

First you need to clear the site of debris, remove 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 on them, mark the outer edge of one of the foundation walls. Next, the second rope with the same U-shaped structure is pulled perpendicular to the first. The markup is carried out in the same way for all other external boundaries of the concrete base.

The next stage 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 angles - 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 get all the angles at 90 degrees.

Following the designation of the location of the main contour, the internal walls of the foundation are marked, which will become the basis for the internal partitions of the building.

Excavation

The markings are ready and now you can start developing the soil. Trenches should be dug strictly according to taut ropes... As noted earlier, the depth of the foundation is selected depending on the depth of soil freezing. At the same time, the height of the trenches under the inner walls of the 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 for the strip foundation. If the depth of laying the concrete base is less than 1 m, then it is permissible to make the walls vertical. In the case of deeper excavation, the walls must be made with a slight slope.

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

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

Material calculation, required 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 slats required also depends on the depth of the foundation and the width of the wooden product... After all, the boards are knocked down by beams 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 beams, the step of their location should be no more than 40 cm. Depending on this, the number of necessary beams is also determined. So, for work you will need the following materials:

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

To arrange the formwork for the strip foundation, you will need tools:

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

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

Laying the sand cushion. Considering that the weight of the concrete structure is very high, a layer of sand must be laid to distribute it evenly on the ground. The height of the pad, which is tamped down and moistened with water, is 150 mm. On a flat and solid base, you can start the installation of the formwork.
Installation of guide boards. This procedure must be carried out strictly along the line, therefore, in advance, pull the fishing line along the entire length of the trench. After that, install the guide boards according to the marking, securing them with pegs and vertical beams with 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.
Installation of shields. We attach the boards to the beams and connect them with nails. The procedure is performed from the bottom up.
After assembling the shields, we put the spacers. Bars can also be used as the latter. As a result of the installation of the spacers, the shields must take their final position, that is, the formwork will take the form of the walls of the future foundation.

Correctly executed formwork for a strip foundation is a guarantee of the strength and durability of the building

Important: Use tow or thin strips to seal the resulting cracks.

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

Nuances of work

If the height of the formwork exceeds one and a half meters, then a window must be made at the bottom of the trench to remove industrial debris, which in this case can be very much.
A layer of waterproofing material is laid at the last stage of formwork installation, before reinforcement.
If it is intended to reuse a collapsible structure, then an oily substance must be applied to its inner surface in order to minimize adhesion to concrete.

The correct strip foundation for the house

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

We make do-it-yourself formwork for the strip foundation - required 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 under the strip foundation is subject to increased requirements for rigidity and strength. The structure should not change in size and shape when pouring concrete. The dynamic load accompanying the do-it-yourself foundation process should not be a test for the formwork.

Basic requirements for formwork

In addition to the properties fixing concrete, the formwork provides an optimal temperature and humidity regime - a prerequisite for the full hardening of the solution. If these conditions are violated, the design strength of the finished support will be seriously reduced.

Important note: a competent formwork arrangement implies the use of materials that are chemically neutral.

Appearance constructions

Any structure must be made in such a way that it can later be easily disassembled without deforming the concrete.

Formwork without concrete preparation

If you want to make a formwork under Vacation home, most often we mean a shallow type of foundation on tapes. Such a base is able to withstand the weight of a small house, and the formwork does not take much time and effort. All operations can be done by hand, the formwork in such cases is a small-panel collapsible structure.

In the absence of a concrete screed under the strip base, the formwork is the soil walls of the pit, dug under the strips. A prerequisite can be called from below, the thickness of which should not be less than 20 cm.

Formwork for a strip foundation - the manufacture of a structure from panels with a dense and durable structure. Boards or sheets of plywood (even used ones) can be used on the boards.

The following requirements are imposed on the shields:

thickness - from 4 to 5 cm;
humidity - below 21-23%;
width - 15 cm on average.

The maximum gaps between the boards are 2 mm. Installation of formwork panels is carried out on braces resting on stakes driven into the ground. The distance between the braces is determined by the dimensions (height, width and thickness) of the foundation itself.

Important: if the house has standard dimensions, the braces are installed at a distance of 1 meter from each other.

To fasten the tops of the formwork under the strip foundation, the cuts of the shields are fixed with wooden jumpers. This prevents the structure from opening during the concreting process and the spreading of the mixture. The step for installing the fastening bars is from 50 cm to 1 m. To prevent the structure from bending to the sides, a 2-meter rail is used to control it.

In order for the formwork for the strip foundation to maintain the optimal temperature and humidity parameters of the concrete, the structure is lined with a layer of waterproofing from the inside. The waterproofing material is polyethylene film, EDPM-cloth, PVC or others.

The importance of waterproofing is difficult to overestimate: wood is a material with a porous structure. To prevent moisture absorption from the concrete solution, insulation is laid. Water from cement laitance can seep not only into the walls of the formwork, but also into the ground. Therefore, the construction device with your own hands must be done correctly - the installation of the waterproofing layer should provide for the horizontal exit of the concrete mass. The bottom of the trench is covered with several layers of material, which is attached to the walls with a stapler.

Important: when installing the formwork under the strip foundation, its height should exceed the concrete strip by 5-7 cm (video).

Creation of combined formwork

If you want to make a strip base on crumbling soil, it is necessary to make a removable non-removable formwork. Do-it-yourself installation of a structure allows you to save a certain amount of money, but it takes time and effort.

The correct combination formwork consists of 2 parts:

internal - non-removable, which is made of expanded polystyrene plates (thickness - from 5 to 10 cm);
external - a standard design, which fixes the PPS plates in the desired position with small shields.

Installation of expanded polystyrene is carried out as follows: the material is attached to the ground on ordinary 20-cm nails, to wood - on removable self-tapping screws. The manufacturer supplies its polystyrene foam sheets with thorn-and-groove locking mechanisms that prevent the mixture from flowing out and water seepage.

Important: PPP is much more profitable than wood and does not need additional insulation. Among other things, the installation of lightweight sheets is comfortable and quick.

To keep the expanded polystyrene in an upright position, do-it-yourself installation of a wooden crate. On this topic you can find detailed video online.

Correct installation of removable non-removable formwork pursues a number of tasks:

insulation of the foundation above and below the ground;
waterproofing tape base;
creation of a removable layer on which the soil load is distributed;
shaping smooth surface able to withstand the force of frost heaving.

Nuances of construction

To on concrete screed, it is necessary to withstand the time period before it hardens.

When choosing a material for formwork, preference is given to moisture-resistant types of plywood - FSF or bakelite plates. Do-it-yourself plywood boards need to be strengthened with wooden bars. Numerous forums and resources on the construction topic contain photo and video reports of a detailed description of the procedure.

To prevent the formwork from deforming the concrete surface during dismantling, the inner surface of the panel structure is lubricated with any of the following compounds:

cement mortar;
hydrophobic mass;
lime milk.

If it is impossible to make the formwork with your own hands (there is no strength, time or for other reasons), the structure can be rented from a specialized company. Rental price 1 square meter imported formwork - starting from 260 rubles. per day of operation. Professional formwork has several advantages:

creating a perfectly flat foundation surface;
the formation of clear angles;
saving time and effort.

The construction of the foundation is a laborious and expensive process; in individual construction, the only way to save money is to perform all the work (or separate stages) on their own. In particular, this concerns the device of formwork when pouring tape-type bases, with the right approach and the study of video instructions, its installation, fixing and removal will be carried out even by a non-specialist. The material of the shields and supports can be anything: plastic, metal, moisture-resistant plywood, boards. Wood is used most often for reasons of economy, ease of assembly and fitting to the desired dimensions.

On preparatory stage the foundation is marked, its perimeter is calculated. The formwork is placed on even and compacted layers of a drainage pad made of sand and gravel. Shields and supports are assembled in advance, the interval between digging a trench and their installation should be minimal, otherwise the walls will begin to crumble, and rain moisture will accumulate at the bottom. It is easy to calculate the required number of boards or plywood for formwork for a strip foundation, just know its area. Up to 90% of supporting structures in private construction are made of wood, their thickness depends on the mass of the concrete to be poured and the purpose of the building. The minimum for timber is 50 × 50 mm, plywood - 10 (provided it is supported), boards - from 22.

Construction technology step by step

Consider the standard instructions for building formwork with your own hands in stages (you will find more recommendations in):

1. Drawing up a foundation diagram, selection and calculation of material.

2. Knocking down shields. The boards are sawn into pieces of the same size, fastened to the timber with nails or self-tapping screws, with hats inside. Deviations in level are inevitable (they are not possible unless using plywood), but it is important that they do not exceed 2-3 cm. Gaps and slots are unacceptable: large ones are clogged with thin slats, small ones - with tow. This stage is easy to carry out by yourself, the help of one more person is required only with limited lines.

3. Lowering and fastening the formwork panels to each other. The method of fixation depends on the type: removable twist on the outside, non-removable (from expanded polystyrene, fiberboard or other DSP) - as it will be more convenient. The corners require special attention.

4. Installation of spacers (wooden blocks or pieces of plastic pipes in reusable formwork between panels with a length equal to the width of the strip foundation) and fixing the structure from the outside with supports sawn at an angle of 45 °, the other end of which is buried in the ground.

5. Checking the strength and deviations from the markings. Final fixation, sanding the lower area. The line marks the top edge of the base.

6. Flooring inside the waterproofing film. This step is optional, but it is recommended to carry out it if there are gaps between the boards and for the convenience of removing the formwork. When working with panels made of plywood, plastic or metal, the inner surface should be lubricated with oil.

7. Pouring and distribution of concrete inside the formwork for the foundation: in layers, but without significant interruptions, with compaction every 20 cm and leveling the upper edge with a trowel. With correctly selected boards and reliable fixation, the structure does not bend under the weight of the mortar and remains motionless when the air is forced out. It is this condition that allows you to get a stable foundation.

8. Dismantling of the formwork - depending on the brand and the time of concrete hardening, but not earlier than 3 days. Private developers remove it after 70% of hardening - that is, after 2 weeks. The main sign of the admissibility of such an operation is the appearance of a gap between concrete base and formwork. The work should not be done by yourself, especially when removing large supports.

After that, they proceed to the next stage of the construction of the strip foundation with their own hands: waterproofing, if necessary, insulation, backfilling with soil. A somewhat different (simpler) scheme of actions is observed step by step during the installation and operation of non-removable forms of formwork, recommended for construction in areas with soils strongly frozen in winter. Structures with walls made of expanded polystyrene or DSP reduce the load on the foundation and give it stability. They are easy to assemble on your own, but unlike ordinary wooden ones, they remain in the ground (points 8 and 9 of the given instructions are skipped).

If the height of the strip foundation exceeds 2 m, the formwork panels are advised to be made of solid materials, and not knocked out of the boards. In this case, square structures are considered the most durable; when installing too long, the requirements for the number and reliability of stops and internal struts increase. If the foundation is deeply laid due to increased costs, it is worth considering the option of renting the formwork.

Contacting specialists (at least - consulting) is required when conducting construction on loose soils. In addition to increasing the number of supports (with a standard pitch of 0.9-1 m), it is recommended to combine materials, for example, plywood formwork boards from the inside. The opinion of professionals is also important when organizing vertical and lateral supports with a significant rise of the tape above the zero mark, the latter variety in some cases is even screwed to the walls. The standard maximum is 15 cm above the ground level; if it is exceeded, the formwork for the future base is supported from all sides.

When choosing an internal waterproofing, two factors are taken into account: the budget and the size of the filler fractions in the concrete. It is not recommended to use roofing material for these purposes, it is inferior in flexibility to polyethylene (especially in winter). Most often, the choice is made between a thick film and moisture resistant plywood, the second option is optimal when working with heavy coarse concretes.

Rough ground rules

The above instruction implies the laying of a standard strip foundation; when working on a slope, the process becomes more complicated. In this case, the base is made stepped, at the lowest point the formwork is made higher, at the top the tape should rise above the ground. The bottom is required even under any conditions, by analogy, layers of sand and a larger filler are gradually filled up and compacted, it is recommended to fill in a layer of lean concrete.

This type of foundation on a slope will be advisable when building a house made of heavy bricks (but with drops of more than 1 m, the costs increase unreasonably, the height of the tape at the lowest point is not allowed to exceed four times its width); for light buildings, a pile-grillage type is considered a good alternative. The formwork for pouring the hanging grillage is distinguished by the presence of a bottom and additional supports (the weight of the concrete is directed towards it, and not to the ground).

Error propagation

Violations of technology when installing formwork for a strip foundation include:

Using uncut or oversized boards. The correctness of the cement hydration process depends on the evenness of the inner surface and the absence of cracks. Serious deviations or gaps lead to mortar flow, hardening of the tape with uneven walls (more susceptible to the effect of groundwater).
Installation of formwork for a foundation made of overdried wood (for similar reasons). In this case, preference is given to raw boards.
Errors when choosing thickness and width. It is wrong both to use plywood without deck support, and to knock overly thin boards.
Removing the formwork ahead of time, rough dismantling (pulling off with force).
Installation of the formwork on an uneven base.
Lack of internal struts at the beginning of concreting. There is an important rule: all wooden elements are removed as the formwork is filled with concrete. It is permissible to leave only reinforcing steel ties inside the tape.

Ignoring the rules is fraught with bending of structures and overconsumption of concrete, leakage, the formation of uneven walls and difficulties in further finishing the strip foundation. The involvement of specialists is required if it is necessary to pour concreting in winter, work on difficult soils, and limited installation times.

Incorrectly assembled formwork from boards can be strengthened - it is enough to punch it from the inside with moisture-resistant plywood. If you wish to reuse the supporting and panel structures, the removed panels are washed, leveled and dried.

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 required shape. This device is used to make foundations. different types... The most common application is to form strip foundations. With the help of formwork, they make reinforced belts for floor slabs or roof frame of a building, as well as many other structures in which it is implied that the form is filled with concrete or cement mortar... The material for the foundation formwork can be used in different ways, and in our article we will consider several options.

Wooden formwork with waterproofing coating

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)... Implies the reuse of functional parts of the fixture. It is dismantled after the reinforced concrete has hardened.
Non-removable... Remains in the foundation, while serving as an additional protective or decorative element of the structure.
Wooden... It is used in collapsible structures. Edged wooden boards of different sections, plywood, OSB boards, and in rare cases chipboard are used as the main enclosing material.
Metal... The enclosing elements in such a formwork are made of sheet metal. Nodes that provide rigidity and prevent deformation of the planes can be made of wood or a metal profile.
Polymer... It can be both removable and non-removable. In the first case, it implies the use of special plastic sheets as a fence. In the second, concrete is poured into expanded polystyrene molds, assembled by means of locks into an integral structure.

Reusable formwork - often rented out

Overview of typical formwork: types and conditions of use of formwork structures

Depending on the requirements for the reinforced concrete structure, a 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 must be.

Demountable formwork

This is the most common formwork device for strip foundations and more. Its popularity is due to its ease of manufacture, availability of material and low cost compared to other options.

Most often, such formwork is built from OSB, panels from wooden planks, plywood, sometimes chipboard. As a material for the frame, a wooden beam of a suitable section is used or metallic profile... All material after dismantling the formwork can be used in further construction works Oh. Naturally, this is possible with a careful attitude towards him.

Even a single-use formwork can be collapsible, and the boards are quite suitable for a sub-floor or similar work.

From planks

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

disadvantages: long-term assembly of panels and subsequent assembly / disassembly of construction elements; the structure requires additional reinforcement.

Advantages: low cost.

Plywood, chipboard, OSB

So that the formwork from OSB for the foundation, or from plywood and chipboard, is durable, you cannot do without wooden beam, which will be necessary when assembling the frame and stops with braces. The recommended thickness of the slabs is 18 mm or more. The thicker the slab, the less timber for rigidity will have to be added. Sheet 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 out). If many pouring cycles are planned, you should pay attention to the laminated waterproof plywood.

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

Positive traits: simplicity and speed of assembly in comparison with all other collapsible options. When using cheap types of slabs, the cost of such a formwork for a foundation will be lower than that of a wooden one.

disadvantages: high cost of waterproof film faced plywood; one-time use of inexpensive board materials.

Metal formwork

Expensive but practical option, capable of providing a high surface quality, which reduces the cost of its subsequent grinding (if any). Such structures are more often factory-made, therefore, they are maximally adapted for quick assembly... They have significant rigidity and the same significant weight, 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 using them to save on workers' wages and cranes is impractical.

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

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

Polymer boards

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

Polymer formwork is an expensive pleasure, but they are indispensable in the construction of typical structures.

Fixed design

When choosing a material for non-demountable formwork, one should choose the 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.

Expanded polystyrene blocks

A very simple and quick option, moreover, the finished concrete structure is already insulated. The manufacture of formwork for a strip foundation from blocks evokes an association with the designer: lightweight polystyrene blocks high density assembled by means of locks located on the adjoining 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 sheets of dense polystyrene are used as the limiting material. Joining of sheets to each other is realized using a simple tongue / groove connection. Opposite walls are connected with special metal brackets, which in parallel determine the width of the foundation strip.

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

Fixed formwork also works as insulation

Reinforced concrete foundation blocks

The name speaks for itself. Structurally, it resembles expanded polystyrene formwork. The difference is the lack 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 installation.

Auxiliary materials and necessary tools

In the process of installing 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 an improvised sheet material is used. Factory products are usually equipped with everything you need.

Metal studs

Required for tall buildings. It is not possible to provide high-quality fixation of the tape thickness over the entire area of the fence by other methods. 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 the expansion of the formwork walls. For proper functioning, the stud is installed in plastic pipe... This is done in such a way that when tightening, the walls of the fence from the inside rest against the pipe. WITH outside it is recommended to put on washers on the hairpin.

Braces

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

Polyethylene film

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

Manufacturing of removable formwork for a 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 the formwork is made for a strip foundation using wooden panels and timber.

Manufacturing technology of wood 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 optimal length of the board is 2 - 2.5 m.

When manufacturing, it is better to use nails as fasteners. This will greatly facilitate dismantling, save money and speed up the process.

For shields up to 1 meter in height, 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 bundling of boards, you can use a bar with a section of 50 * 50, - for one shield 4 pcs;
The board is nailed to a beam, which is located at regular intervals, while at the edges of the ends there should be a distance of about 200 mm (to tie the boards together during installation). The bars should be made slightly 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 must be used, a bar for the frame - at least 100 * 50 mm.

Installation work

You must first make a markup. After that, the shields are located along the foundation tape. Outside, the tapes are fixed with braces, and stops or pins are installed from the inside. During work, it is necessary to control the level in all planes and the geometric accuracy of the structure.

Video description

You can clearly see the formwork for the foundation in the video:

Assembly of permanent 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, after having laid the waterproofing with an approach to the walls of the trench (in the case of a trench version). The assembly is carried out into locks on the edges of the blocks.

The height is gaining, at which it is possible to tie the reinforcement without significant difficulty. In the case of using polymer sheets, the walls are fixed to each other with brackets that come with the kit. Having typed several rows and untied the reinforcement, they are poured with concrete, after which the next rows are assembled and so on until the structure is fully ready.

The process is the same for non-separable concrete block formwork. 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 takes place gradually - after pouring one or two rows, the next ones are mounted.

Video description

For more information about fixed formwork, see the video:

Outcomes

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 timber 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 be expensive.

The most important part of any structure is the foundation. occurs only after the arrangement of the formwork. Such a structure is mounted in case of compliance with all rules and regulations. Before starting construction work, study the types of formwork and read the instructions for their installation.

Types, device, materials, requirements

For beginners in construction, the question arises: "What is formwork for the foundation?" This is a metal or wooden structure that helps to give the desired parameters (shape, position, structure) to concrete or primer solutions. It consists of form-building elements, fasteners and supporting materials.

There are two main types of formwork: removable, which must be removed after the poured mixture hardens, and non-removable, which remains part of the structure. By structure, frame, beam and tunnel systems are distinguished.

Before installing the formwork, it is worth checking it for compliance with the requirements:

the dimensions of the structure must be strictly calculated;
it is obligatory to check for cracks and cracks in order to avoid getting the solution into them;
the formwork must be resistant and strong to withstand concrete of any weight;
the correct choice of fasteners is important, they will help to carry out easy installation and dismantling.

Various materials are used for foundation formwork, the most popular of which is wood. The main requirement is that any material must create a flat surface.

Removable formwork

Removable formwork allows you to apply it to walls, ceilings, for casting columns or reinforced concrete elements. Experts distinguish modular, inventory structures made of metal, which have a high accuracy of element compatibility, reliability and a large number of cycles of use. Used in monolithic construction.

From planks

This option is the most common. To equip the formwork, sheet plywood is used either. The main advantages of this material are low price, ease of use. A negative factor is the need to use additional tools that help to strengthen the structure. For beginners in construction, it is best to use do-it-yourself plank formwork to avoid further problems with pouring the foundation.

Plank formwork

Plywood, chipboard, OSB

Formwork made of such materials is suitable only for small buildings. Its main advantage is its low cost, the disadvantages are the complexity of use, the danger of solution leakage, the use of additional supports and low bearing capacity.

Fixed formwork

The main characteristic of permanent formwork is that after the concrete has set, it remains in the foundation forever. Such a structure is assembled from scrap materials, from fiberboard and particle board, installation is much faster and more economical. If it is necessary to increase the strength of the base, materials such as metal hollow pipes are used for formwork.

Made of metal

The most expensive formwork material. Steel sheets with a thickness of 2 mm are used. This type of formwork is suitable for the equipment of strip and monolithic foundations. The reinforcement is nailed to the sheets, and the sheets themselves are bent under the shape of the concrete base. The main disadvantage of this material is its high cost.

Styrofoam

Is a quality and practical choice. It is easy to install and takes any shape. But the material also has a number of disadvantages - a rather high price and difficulties in the selection of elements.

Fixed formwork made of expanded polystyrene

From reinforced concrete blocks

Expensive formwork - use concrete slabs... By increasing the thickness of the formwork, the amount of concrete base required can be reduced, which can save construction costs without compromising the quality of the building. But at the same time, due to the large weight, you will need to install additional props, which will also require certain funds.

How to make do-it-yourself formwork?

How to make do-it-yourself foundation formwork? There are several ways to mount the structure.

The first way

Do-it-yourself fixed formwork for the foundation is installed according to the following instructions:

dig a trench according to the size of the future foundation, according to the drawn up project;
there should be a gap of 2 centimeters between the formwork and the ground for ease of installation;
after wedging, the gap is covered with earth;
cover the bottom layer of the pit with sand and gravel, tamping each layer;
install a reinforcing mesh on the embankment to increase strength;
choose the fastening methods yourself, paying attention to the features of the selected material;
pour concrete and let it harden for about 28 days, after which continue construction.

DIY foundation formwork

Second way

Installation of removable formwork is performed in the same way:

we mount the fixed structure to the corner of the foundation;
we drown out with shields;
pour concrete mortar into the reinforced formwork;
expect hardening;
untwist the structure;
move and fix it in a different place.

Stops (spacers) and braces

In order to avoid the destruction of the formwork under the weight of the base, it should be carefully secured with braces from the outside. They should be no more than one meter apart. On both sides, stops are placed in the corners where the greatest load is. If the height of the shield is more than 2 meters, then it is worth building two levels of spacers. Stabilization of the distance between the two panels is carried out using 10 mm studs, nuts or metal spacers. Hairpins 10-15 centimeters long. The assembly of the structure is carried out in the following sequence:

holes are made on the shields;
a piece of pipe is mounted between them;

Spacers on the formwork for the foundation

a hairpin is held;
installation of metal plates;
the nuts are tightened.

During the removal of the formwork, the nuts are unscrewed and the studs are removed, then the shields are removed.

DIY polystyrene foundation assembly

Polystyrene formwork avoids dampness and insulates the structure. First, check the surface of the foundation and level it if necessary. We carry out the markup, select the corners and other important elements. Connect the blocks along the perimeter of the building, especially in the corners. Check all markings and installation with a spirit level. Next, the stage of installing reinforcement and pouring concrete is coming.

How to spend less?

When installing the formwork, it is really a good idea to save money. One of the ways is to pour the formwork within a few days, this is especially true with a great depth of the foundation. This will not harm the strength of the fill in any way. You can split concrete horizontally and vertically.

It is important to calculate this process according to the plan. If the depth of the foundation is 1.5 meters, it is enough to divide the pouring into three stages of 50 cm each. Follow these instructions:

tie the reinforcement for the entire volume of the formwork;
pour concrete in height;

Filling the foundation with layers

after 7 hours, remove the top layer of cement laitance on the surface. It should be removed, as this layer becomes very fragile when hardened. After removal, the surface will become rough, which will increase the adhesion to the next layer;
after three days, lift the structure and set it to a higher level. Leave the tubes in the concrete;
refill the exposed formwork.

Vertical division

Splitting the plan vertically is another fill method. The joints must be placed at a certain distance when dividing the foundation into several parts. There are a few things to do:

Formwork in those parts of the building where the part to be installed ends.
Knit a reinforcing cage.
Reinforcement rods must extend beyond 50 diameters.
Pour concrete over the area.
After 7 hours, peel off the top layer vertically.
Apply another layer.

You will find many useful materials on our website:

? It should be borne in mind that waterproofing cellars is an important element of the arrangement of buried premises. The main task is to prevent the penetration of water into the basement and to ensure its dryness. Examine the depth of the water carefully and select the correct insulating material. The right approach to business will help avoid problems with food storage.

Before making a screed with expanded clay, study all the subtleties of the expanded clay material itself and the technology for making such a screed. It is advisable to heed the advice of professionals and pour a concrete layer 3 cm thick. Then the floor will not crack and will eliminate all irregularities.
How ? This is a very laborious process, which depends on many factors: what type of house (wood or stone), what soils, etc. Thanks to the correct selection of tools and materials, you can provide yourself with a reliable foundation for your house.
To answer the question is it possible, compare all the pros and cons. Do not forget to take into account the properties of aerated concrete blocks: it is economical and fast, but staying in the bath will be uncomfortable because of the non-breathing walls.
He plays an important role in the durability of any building with his own hands, the main goal of which is to create a stable and even platform for the foundation and ensure less settlement. WITH correct styling cushion construction will last for hundreds of years.
– fashion trend and an indicator of the quality of the practicality of the work, their speed. The main thing is to develop the correct project before starting such events and be sure to take into account the analysis of the soil on the site.
The question is often asked: "What?" There is a wide variety of materials and technologies used, but be sure to remember that exterior decoration should conduct steam well. Then the moisture from the house will be removed naturally.

Outcomes

The installation of formwork is a process that requires special care, because further construction, strength and reliability of the foundation depend on it. If you follow the advice described in the material, then the foundation laid will serve you for more than a dozen years.

Did you like the article? Share it

Print article