Pile foundation in a swampy area. Cheap shallow foundation for a house in a swamp. Strip foundation in the swamp

What is more profitable

- with walls made of flexible timber or brittle aerated concrete? In each case, the answer to this question will be different.

How to make a foundation for a country house in areas with swampy soil.

Plots with weak wetlands are considered unfavorable for building a house in terms of soil conditions.

You can build a house on any soil, you just need to do it right.

Soil properties in wetlands

Wetlands are characterized highly compressible soils. These soils include:

• Loose sands and sandy loams, water-saturated fluid-plastic and fluid consistency with a porosity of more than 41%.
• Loams with a porosity of more than 50% and clays with a porosity of more than 52%.
• Peaty sandy and clayey soils. Peaty soils are soils containing less than 50% organic matter.
• Peat is soil that contains more than 50% organic matter.
• Silt is a highly porous water-saturated sediment formed as a result of microbiological processes in water bodies. Soil porosity can reach 60%.
• Sapropel is a water-saturated sludge containing more than 10% organic matter. Its porosity is up to 75%

All of the above soils have high humidity - up to 80%, and low bearing capacity for loads from the weight of the house. For example, the design load resistance for sludge is 0.4-0.6 kg/cm2, for peaty sandy soils - 0.4-2.5 kg / cm 2.

Waterlogged areas may be of natural or artificial origin. Waterlogging can be the result of human activities. Sometimes waterlogging occurs after the construction of a house on the site.

Artificial swamping of the site lead to:

• Raising the general level of the soil during the construction of roads in the village and during construction in neighboring areas. As a result, the natural flow of water from the areas below is disturbed.
• Construction of fences on a solid strip foundation without water channels.
• Lack of organized storm water runoff on the site and on the territory of the village.

The process of artificial bogging usually takes several years.

Due to high humidity and high groundwater levels soils in wetlands are highly heaving.

A house built on weak and heaving soils is exposed to an increased risk of destruction, as a result of significant settlement and uneven soil deformations.

Even on a hard foundation a house can gradually sink into a swamp over the years. Under the weight of the house, water is gradually squeezed out of the pores of the soil, the soil under the house is compacted and the house gradually settles every year.

How to make weak ground stronger

The layer of weak swampy soil in different areas has a different thickness. For example, in one area, a layer of weak soil may not be thicker than 1 meter. On the other - more than 10 meters. Under the layer of swampy soil there is always a layer of low-compressibility soil with “usual” properties for construction.

The bearing properties of weak soil can be improved in the following ways:

• Vytorfovka - replacing marshy soil with a pillow of non-porous soil. The replacement is carried out under the sole of the foundation for the entire thickness of the marshy soil layer or partially.
• The device of the foundation on an embankment of non-porous soil.
• Soil compaction under the base of the foundation.

Building regulations prohibit the support of the soles of the foundation of the house directly on weak ground. Therefore, pillows and embankments are a necessary element in the design of the foundation on soft soils.

Features of the design of the house on soft soils

When building on swampy soils, constructive solutions are used to reduce soil settlement by reducing the specific pressure of the house on the ground. To reduce the sensitivity of the house box to uneven deformations, the rigidity or flexibility of the building's load-bearing frame is increased.

To reduce the specific pressure of the house on soft ground and increase the rigidity or flexibility of the building frame, the following design measures are used:

• They increase the area of ​​​​support of the foundation on the ground through the use of a foundation - a slab or a strip foundation with a broadening of the sole.
• They increase the spatial rigidity of the foundation due to the installation of a monolithic reinforced concrete foundation. (Prefabricated strip foundations made of blocks or masonry materials are not used.) They increase the rigidity of the slab foundation by installing stiffeners or making the foundation-plinth of increased height. Additionally, a monolithic reinforced concrete floor is arranged, rigidly connected to a monolithic basement-foundation.
• The spatial rigidity of the building frame is increased by arranging monolithic reinforced concrete belts at the level of floors overlapping and reinforcing the masonry of stone walls.
• Pile foundations are used with support on the underlying low-compressible soil layer.
• On weak soils, it is advantageous to build houses from light and flexible building structures - logs, timber, frame. The cost of building foundations for such houses is much less than for fragile houses made of stone materials.

The task of choosing the design of the foundation and the design features of the house box is to ensure that determine the most economical option for specific construction conditions.

For example, which is more profitable- to excavate the entire depth of the swampy soil and strip foundation or install a pile foundation or pour a foundation slab on an embankment? Which house will be cheaper to build on soft soils- with walls made of flexible glued laminated timber or brittle aerated concrete? In each case, the answer to this question will be different. The correct answer can only be obtained from specialists - designers.

Managers of construction companies usually try to impose a foundation option on the developer, based on their interests, the more expensive the better. Or they can, in order to keep the customer, offer a very cheap option, agreeing to which, the developer will later bitterly regret.

The figure below shows the arrangement of an artificial soil base and a slab foundation for a stone house on soft marshy soil.

Slab foundation for a one-story house with cellular concrete walls with brick cladding. 1 - thickness of weak marshy soil - 10 m; 2 - sand cushion; 3 - embankment; 4 - planning filling; 5 - base plate; 6 - base; 7 - waterproofing; 8 - blind area; 9 - groundwater level - 0.4 m from the surface.

Consider the measures taken by the designers of the foundation, allowing you to build a house on weak marshy soil.

To improve the building properties of the soil at the base of the foundation:

• Partial excavation was completed - the vegetative layer of soil was cut off in a section with a thickness of 300 mm. (slightly above the groundwater level). In the resulting recess, a sand and gravel pad is arranged, item 2 in the figure.
• An embankment, pos.3, was made from non-porous soil. The soil in the embankment is laid with layer-by-layer compaction. Under the weight of bulk soil, the underlying layers of weak soil are compacted and settled. It is recommended to start building a house 6-12 months after filling to allow time for settlement to stabilize.

After the device of the slab foundation, the planning filling of the soil is additionally carried out, pos.4. Planning filling is carried out with any soil.

Building a house on an embankment contributes to the general rise in the surface level of the site, ensures the removal of melt and rainwater from the house and from the site.

The height of the embankment, pos. 3, can be reduced by increasing the thickness of the sand cushion, pos. 2, so that the total thickness of the fill soil of the cushion and the embankment remains unchanged. It should be borne in mind that it is quite problematic to pour and compact the cushion soil in water, below the groundwater level.

Constructive solutions for building a foundation for a house in a swamp:

• To reduce the pressure of the house on the ground, a slab foundation was used - a monolithic reinforced concrete slab under the entire area of ​​\u200b\u200bthe house, item 5 in the figure. Moreover, the dimensions of the foundation slab are increased and go beyond the walls by 300 mm. from each side.
• The spatial rigidity of the foundation is increased by installing a monolithic reinforced concrete plinth, pos.6, connected with reinforcement outlets to the foundation slab.
• A monolithic reinforced concrete floor at the top level of the basement can further increase the rigidity of the foundation. The single structure of the basement space box made of monolithic reinforced concrete is a fairly rigid foundation for a stone house.
• At the house with the walls of their aerated concrete, and arrange a monolithic reinforced concrete belt at the level of the floors.

The foundation structure shown in the figure was designed for rather difficult soil conditions: the soil is water-saturated silt with a thickness of 10 m., high groundwater level - 40 cm. from the surface.

For more favorable soil conditions, the volume of pillows and embankments, as well as monolithic reinforced concrete at the base of the house, can be significantly reduced.

Increasingly popular with private developers variant of the slab foundation - insulated Swedish slab. In this option, a heater is placed under the monolithic foundation slab, and the stiffeners are directed downward into the ground. The foundation slab serves as the base for the walls and the base for the floor of the first floor. Some disadvantage of this foundation design is the low base. In conditions of a significant thickness of snow cover in most climatic zones of Russia, increases the risk of wetting the bottom of the wall of the house.

The reinforcing cage for reinforcing the foundation slab of a private house usually consists of upper and lower reinforcing meshes and vertical ties between them. The number of reinforcement bars and their diameter are determined by calculation.

In the case of the construction of heavy two-three-story brick houses in difficult soil conditions, it may be more profitable to build a foundation on driven piles.

On weak soils with a layer thickness of less than 3-5 m. Consideration should be given to the feasibility of building a house on bored or screw piles supported by an underlying low-compressibility soil layer.

Shallow strip foundation for a house in a swamp

Houses with frame walls, as well as with walls made of logs and timber, are more flexible - they can withstand much greater deformations than stone houses. Such houses in the swamp can be built on shallow or shallow strip foundations.

The shallow-depth monolithic strip foundation under the outer and inner walls, item 3, is a single spatially rigid frame. In order to increase rigidity, the height of the foundation tape, combined with the plinth, has been increased. The wide sole of the foundation is located at the level of the soil surface on a sand and gravel pad.

For the foundation shown in the figure above, it is enough to make reinforcing meshes in the upper and lower chords from three longitudinal rods with a diameter of 12 mm, class A-III. Reinforcing bars in the mesh are connected with auxiliary connections made of wire Vr with a diameter of 6 mm.

The upper and lower grids are connected by vertical rods of transverse reinforcement with a diameter of 8-10 mm, class A-III. Concrete protective layer for foundation reinforcement at least 5 cm.

Previous article:

If you got a wetland for building a house, you don’t need to be upset, with modern technologies it is possible to build a house in a marshy area. The main thing is to choose and build the foundation correctly - the basis for the house. And we'll suggest what foundation is better on swampy soil.

This is a multilayer heterogeneous structure, which includes clay, peat, sandstone and has a different density. It is supersaturated with moisture, with a large number of fine-grained particles that resist little compression. The instability of the soil leads to the fact that it is difficult to determine the limit of the load that it can withstand. Therefore, swampy soil is considered the most difficult for building a house. Before determining the type of foundation, the area and depth of its laying, a thorough study of the geological situation on the site is necessary.

Geological studies of the soil

They are needed to determine the main indicators of the soil. These include:

• volume of soil water;
• soil type;
• the level of soil freezing;
• surface proximity to groundwater.

It is necessary to use a manual probe for soil sampling. At least 4 wells must be drilled on the site (at the corners of the future foundation). It is better to do this in the spring, when the soil is most saturated with moisture. Soil sampling provides the following information: composition, physical properties and thickness of the layers, their depth, soil changes over the past few years.

For a wooden house, you need to drill a well with a depth of 5 m or more, for brick or stone houses - 8–10 m. Do-it-yourself foundation on swampy soil can be built if professional geologists make an assessment of the state of the soil.

It is important to consider the depth of soil freezing. Insufficient depth of the foundation can lead to its destruction. The information obtained as a result of engineering and geological research will help determine the type of foundation that is right for you.

Types of foundations for swampy soil

Work on the arrangement of the foundation is the most time-consuming and expensive stage of construction, which, on swampy soil, is at least one third of the total estimate of all the costs of building a house. Long-term studies have shown that any foundation on swampy soil begins to collapse after a few years if it does not reach the depth of seasonal freezing. On the south side, where the soil is most moist, it begins to "bulge" out of the ground if done incorrectly.

Therefore, in order to foundation, erected in the swamp with your own hands, served for a long time make a drainage system. It makes it possible to divert excess water from the site. On swampy soils, three types of foundations are used. Let's take a look at these types.

pile foundation

This type of foundation is considered the most suitable for swampy soil. It has the following advantages:

• relatively low prices;
• short construction time (can be built in 2 days);
• construction can be carried out in any terrain;
• work can be carried out in any weather;
• increased durability and resistance to corrosion;
• increased strength and stability.

The use of piles of various heights makes it possible to smooth out uneven surfaces of the construction site. Its main part is the pile itself, which can be installed vertically in the ground or by making a slight slope. They are combined with a grillage (concrete cushion in a reinforcing cage).

In swampy areas, the following types of piles are used:

• Screw piles in a metal shell. They are protected from corrosion with mastic or zinc coating and screwed into the ground using a special lever.

• Reinforced concrete piles (driven into the ground with a manual pile driver).

• Complex combined piles. They are placed in a casing pipe, which is removed after the piles are installed and the site is concreted.

slab foundation

Reliable, but one of the most expensive types. It withstands sudden changes in temperature and heavy loads. The even distribution of the weight of the building over the entire area of ​​the foundation does not allow it to sink, and the sand and gravel cushion located under it allows groundwater to pass through without harming the foundation.

The construction technology is as follows:

1. A shallow pit breaks out (up to about 1 meter deep).
2. It must be drained, using drainage or using pumps (if there is a lot of moisture).
3. At the bottom of the pit, layers of sand and gravel are laid, which are carefully compacted and covered with several layers of roofing material.
4. To pour concrete, formwork is made and a reinforcing frame of at least 12 mm is constructed.
5. The prepared area is evenly poured with concrete mortar and the slab is allowed to dry for several days. Dismantling the formwork.

The plate must be poured at one time. A strip foundation is erected on top of it. Such a base can be made on its own, it is durable, protects the walls from cracks during shrinkage, and allows you to build a basement.

Shallow strip foundation

This is the cheapest foundation, but is only suitable for light structures made of wooden beams and metal frames. He needs a good drainage system, because it is laid above the freezing of the soil. They make it only monolithic, which allows the shallow foundation, due to its own rigidity, to resist heaving of the soil, evenly rising and falling along with the soil. He also needs a good sandy "cushion" and insulation of the base of the foundation.

In our time to lay do-it-yourself foundation on a swampy area and building a house with the observance of modern technologies is not difficult. The main thing is an accurate calculation and a great desire, the rest is a matter of technology. Keep it up, you can do it.

Example with expert comments (video)

If your site, which you plan to use to build your house, turned out to be marshy soil, you should not be upset. Modern technologies make it easy to lay the foundation even in difficult conditions. The main rule in this case will be the correct choice of the type of foundation. You can’t make a mistake, because the life of not only the foundation itself, but the entire building will depend on this.

What is swampy soil?

Before you start building a foundation in a swamp with your own hands, you should familiarize yourself with this type of soil. It is a heterogeneous multilayer structure, which provides for the presence of:

• sandstone;
• peat;
• clay.

The swamp is always supersaturated with moisture and has fine-grained particles in large quantities. They are pretty weak in compression. The soil is unstable, so it is quite difficult to determine the limit loads.

Swampy soil is one of the most difficult to build. Before determining the depth of the foundation, the type of foundation and the area of ​​\u200b\u200bthe structure, it is necessary to study the geological situation.

Features of construction in a wetland: geological research

If you decide to lay a foundation in a swamp for a house, then at the first stage you must carry out geological research. They are necessary to determine the indicators of the soil. It will be necessary to find out what the volume of soil water is, to what level freezing occurs, the type of soil, as well as the surface proximity of groundwater.

A hand probe must be used to sample the soil. Wells are drilled on the site, which are located at the corners of the future foundation. It is better to carry out research in winter, when the soil is most saturated with moisture. Soil sampling provides the following information:

• layer thickness;
• physical properties of the soil;
• formation depth;
• soil change in recent years.

For a wooden house, 5-meter wells are drilled, while if you are planning to build a stone or brick house, then the depth of the well must be increased to 10 m.

Before starting construction on a wetland, it is necessary to determine the depth of soil freezing. If the foundation is laid to an insufficient depth, then later this may cause its destruction. As a result of engineering and geological research, you will receive information that will allow you to determine the type of soil.

What is the best foundation to choose?

The most time-consuming and expensive process in building a house is the work on arranging the foundation. The cost of these manipulations will be 1/3 of the total cost estimate for the construction of the building. After a few years, any foundation in the swamp begins to collapse, but only if it does not reach the depth of seasonal freezing.

On the south side, the base begins to bulge if the work was done incorrectly. In order for the structure to last as long as possible, it is necessary to make a drainage system. It will remove excess moisture from the site. On swampy soils, three types of foundations are used, one of them is a pile foundation.

This design is the most suitable, as it has the following advantages:

• relatively low cost;
• the possibility of construction in any terrain;
• increased durability;
• high stability and strength;
• excellent corrosion resistance.

Screw piles for the foundation can be started in any weather. Construction times are very short. You can complete the foundation device in 2 days. If you use supports of different heights, you can smooth out surface irregularities.

The main part of the foundation is a pile, which can be installed vertically or with a slight slope into the ground. The supports are combined with a grillage, which is a pillow in a reinforcing cage.

Screw piles for the foundation are one of the varieties of supports used in swampy areas. These products are protected from corrosion by zinc coating or mastic. Screwing is carried out using a special lever. Piles can be reinforced concrete, they are hammered with a manual pile driver. An alternative solution is complex combined piles that are placed in the casing. They are removed after the installation of supports and concreting of the site.

Foundation construction based on bored piles

The foundation in the swamp may consist of bored piles. It is being built using one of several technologies, among them:

• with waterproofing;
• with fixed formwork;
• with removable formwork.

Covers are installed in the drilled wells, which are welded from a polyethylene film. The walls are laid out with roofing material, and concrete is poured inside. When creating a pile, you can use a removable formwork made of metal or plastic. 2 hours after pouring, the strength of the concrete will be sufficient to preserve the structure. The formwork is pulled out after the mortar has solidified.

Such supports have one drawback, which is expressed in the fact that they do not have protection against moisture. But the impact of the frozen layer can be leveled by creating a pillow of sand.

The foundation on bored piles in a swamp can be created by the third method, when the formwork is not removed. In this case, it will perform the function of waterproofing. The technology involves the use of pipes from the following materials:

• special cardboard;
• asbestos cement;
• metal.

This method allows you to protect the piles by eliminating height differences and creating a layer of sand between the supports and the walls of the well. Before installation of the structure, water from the well is pumped out by a pump. The lower part of the pipe, which acts as a formwork, is filled with waterproofing concrete per meter in height.

Such a foundation in a swamp requires an increase in the strength of the support. For this, frames made of metal 1.2-cm rods are used. You can also use triangular designs.

Should I choose a slab foundation?

One of the most expensive, but reliable is the slab foundation. It is able to withstand heavy loads and sudden changes in temperature. The weight of the building will be evenly distributed over the entire area of ​​\u200b\u200bthe structure, which will eliminate the possibility of subsidence. Under the slab is a sand and gravel pad that allows groundwater to pass through, preventing damage to the foundation.

Carrying out construction on a swampy area. Slab foundation - is it suitable?

If there is marshy soil on the territory, then you can equip a slab foundation. At the first stage, a shallow pit is dug, and then it is drained using pumps or drainage. Layers of sand and gravel are laid on the bottom, which are well compacted and covered with several layers of roofing material.

Formwork is installed to pour concrete, and a reinforcing frame of 1.2 cm rods is also constructed. The prepared site is poured with a solution, and then left for several days to dry. After that, the formwork can be dismantled.

Such a foundation in a swamp is poured at a time, a strip base can be installed on top. It is carried out on its own, is durable, and when shrinking, it protects the walls from cracking. This technology is relevant for those who want to have a basement in the house.

Alternative option - shallow strip foundation

The strip foundation in the swamp is one of the cheapest, but is relevant only for buildings made of a metal frame or a wooden beam. Such a foundation requires a good drainage system, since the structure is laid above the freezing of the soil. The tape must be monolithic, this provides the ability to resist heaving of the soil.

The structure will rise and fall evenly with the soil. The tape will need a sand cushion, as well as thermal insulation of the base. Such a foundation in a swamp can be poured independently, observing the technology. The work is not too difficult.

Construction of a strip foundation

If you decide to build a strip foundation, then first you need to dig a trench of the desired shape. A pillow of sand is laid at the bottom, and then a reinforcing cage is installed.

If water appears at the bottom, then it should be disposed of by constructing drainage. Next, the formwork is installed and the mixture is poured, which should be left until it solidifies. When everything dries, the surface is covered with waterproofing.

Finally

Peatlands and wetlands are some of the most difficult soils to build. Waterlogged soils are oversaturated with moisture and prone to the formation of unstable quicksand. In winter, such soil undergoes frost heaving, and in spring - erosion. The solid layer lies at a considerable depth, which excludes the possibility of using some types of foundation.

For wetlands, it is best to use floating bases, which are also called monolithic slabs. The design will turn out to be solid, thanks to this there will be no partial shift of the house, while distortions and destruction of the walls will be excluded.

Building on swampy soils can be compared to an extreme sport due to the unpredictability of the results. The main problem of a house on swampy soil is the very poor bearing capacity of the soil and excess moisture. It is possible to build in such conditions only using a guaranteed effective and stable foundation. Not all options for foundation structures will be able to keep the building in a stable position for a long time.

What is the best foundation to use in swampy areas

In each case, the choice of a specific foundation scheme depends on the condition of the soil, the level of groundwater and the types of soil in a particular area. Therefore, before making a decision, it is necessary to conduct exploration and assessment of the nature of the soil, the sources of groundwater that undermine the area, and the depth of the hard rock layers.

Advice! If you manage to qualitatively assess why a given area is flooded, and how to deal with the causes of flooding, you can reduce the cost of a foundation in a swamp by several times.

Depending on the results of the study, you can choose the most optimal option for the foundation for the house:

• Strip foundation with enhanced drainage and deep drainage. Although experts do not recommend the use of tape forms of foundation systems for waterlogged areas, it can be used for certain types of soil in a swamp. For example, for soil with a large amount of coarse river sand, with deep aquifers and the absence of natural springs and springs on the surface in close proximity to the building;
• Pile foundation on bored or concrete supports. When building in a swamp, such a foundation block device is often the only correct and reliable option if the soil soaks to a state of watery porridge. In this case, the piles are driven to the level of solid layers under the bottom of the swamp;
• A floating or slab foundation can be used on very viscous and dense soils in the absence of flooding and rainwater flooding.

When choosing a specific scheme, it is advisable to perform full-fledged deep drainage and drainage of a small area of ​​\u200b\u200bsoil of several square meters. After digging a hole one and a half meters deep, you can try to get an idea of ​​​​the soil of the swamp on which you plan to build a house.

What foundation in the swamp will be the most effective

The main problem in the construction of any buildings is not the technical or technological issues of arranging foundation systems in areas dominated by marshy soil, but the huge costs associated with a large amount of additional work and the need to ensure effective drainage from the basement parts of the foundation. A strip foundation may seem like the cheapest option, but not every swamp can be built.

Strip foundation for a house in a swamp

The construction of a foundation in the form of a tape in terms of the amount of materials used and the amount of work will be the cheapest of the list. If the results of a study of soil geology show the presence of coarse-grained sandy layers up to one and a half meters deep, it is quite possible to get by with the construction of a classic strip foundation. Most often, this situation arises if the owners of the future building choose for construction an area in the floodplain of the river, in a lowland, where swampiness and waterlogging of the soil is associated with the presence of a river.

The construction of a strip foundation in such a swamp is possible only if the following measures are taken:

• The site must be equipped with a very powerful drainage system using hydraulic barriers that prevent the penetration of water from nearby areas;
• The foundation for the house on the site is installed in the highest place, taking into account the possible direction of movement of rain flows;
• Highly efficient soil drainage system adjacent to the foundation.

Before starting work on building a foundation in a swamp, it is very important to make sure that there are no underground springs, which, as a rule, can be quite a lot in such an area. If their presence is confirmed during reconnaissance, it is better to abandon the use of this type of structure in a swamp in favor of other options.

Pile foundation in a swamp - the best solution for heavy houses

If you are planning to build a massive brick house with an attic, you will need to use foundation systems with maximum bearing capacity. For a swamp, this is a pile version of the foundation. The essence of the design of such a foundation in a swamp is to install the required number of concrete or bored piles, based on solid layers of rocky soil under the bottom of the swamp. The cost of such a foundation block for a swamp will be many times more than the previous option. Unlike tape schemes that can hold relatively small frame-type houses in a swamp, a pile version of the foundation for a house in a swamp can easily hold a brick building of several floors for many years.

In this case, for the construction of the foundation, you will have to use special equipment with which you can drill and pour bored piles. Doing this kind of work manually is quite difficult. The depth at which the pile support is installed can reach 5-7 meters, which is determined by the geology of the swamp.

If solid soil layers are at a relatively shallow depth of 2-3 meters, screw piles can be used. They are much cheaper, and in some cases you can even install them yourself. As a preventive measure, the upper layers of soil to a depth of 60-70 cm are often removed, road geotextiles are laid and covered with a sand-gravel mixture. The upper heads of the piles are connected with a powerful grillage or a steel frame of twin channels No. 200.

If the swampy area has a top layer of solid soil, which is often found on peat bogs and lake residues, it makes sense to use a slab foundation, as it is easier and more affordable to do it yourself.

Slab foundation for a small house

The advantages of the foundation system in the form of a solid monolithic slab include enormous rigidity and strength. Such a foundation structure will not float and will not roll, even if the water level of the swamp rises. A good slab foundation is suitable for frame, aerated concrete, foam concrete houses that require special measures to ensure the rigidity of the frame.

The cost of building a slab foundation in a swamp will cost you 20-25% cheaper than a pile version. If we compare the construction of the foundation system on pile supports and the slab option in the conditions of ordinary dry soils, then the cost of the slab will be as much as 40% more than the pile system.

The slab construction technology will require digging a pit 60-70 cm deep, backfilling with a layer of sand and a layer of rubble, laying film waterproofing and installing panel formwork around the perimeter of the pit. For a slab foundation structure in a swamp, in addition to high-quality waterproofing, it will be necessary to lay more powerful steel reinforcement. Most often, reinforcement with a 12 mm bar is used with the installation of jumpers and crossbars. The basement and upper part of the slab must be insulated with polystyrene foam or foam glass.

Conclusion

If you do not know the exact geology of the swamp area on which you are going to build a building, choose a slab foundation option. With lower construction costs compared to piled, it can be done almost by hand, and, most importantly, it will not give you surprises in the form of pushing or failing piles in the liquid soil of the swamp.

• Do-it-yourself foundation for a house made of aerated concrete
• Foundation for a wooden house
• How to insulate the foundation
• Insulation of the foundation with polystyrene foam

A house can be built in any area. It is good if there is stable soil and the installation of the foundation can be carried out according to the usual standard norms and requirements. Another thing is unstable, swampy soils. Here, additional costs are required not only for equipment, but also for proper design, taking into account the specifics of the construction site. Marshy terrain is not the best base for building. But even here, subject to all the norms and requirements, you can bring out a high-quality strong foundation that will serve as a reliable foundation for the house for many years. The main requirement is the correct technology for building foundations on unstable, wet soil. The article details which foundation to choose for a foundation on swampy soil when planning construction in such a problematic place.

Types of foundations and their pros and cons

Swampy soil is not an easy foundation for a foundation. In this case, two types of foundations can be applied: pile and slab. The pile foundation is reinforced with metal or concrete piles, the slab foundation is made in the form of a monolithic reinforced concrete slab, which is poured onto a sand-granite cushion.

slab

The slab foundation is designed to ensure a uniform load of the building on the entire base of the slab. Such a base can withstand heavy loads and is used not only in individual, but also in industrial construction.

Slab technology is applicable on heavily waterlogged soils, unevenly compressible soils, with a high groundwater approach. However, the disadvantage of such a foundation is the inexpediency of installing it in places of slopes. If there is even a slight slope, the plate can “slide”. The special advantages of the slab foundation include its high bearing capacity. The only drawback here is the increased consumption of materials, which is a very painful fact for individual construction.

To fill such a foundation foundation, many times more reinforcement and concrete will be required than when installing a foundation on solid soils, which, of course, will entail an increase in the entire final cost of construction.

pile

Installing a pile foundation in a swampy area is more reasonable and has its own plus in the direction of uneven terrain. Piles can be placed in any hard-to-reach place, on slopes, on any technically difficult soil. Among the advantages of the foundation on piles is not only its installation in hard-to-reach areas with difficult terrain and unstable soil, the advantage is the speed of installation of piles and an acceptable price.

The opinion that a pile foundation is more suitable for small, lightweight structures is incorrect. With an increase in the number of supports, the highest bearing capacity of the base is achieved, which is in no way inferior to the parameters of the slab base. However, this will increase the cost of such a foundation and its cost will be equal to the slab. When building reinforced, heavy structures, this fact should always be taken into account when it comes to the economy of the pile foundation.

Preparatory stage

At the first stage of construction, a full-scale study of the soil is carried out. For this, a manual probe can be used; with its help, soil samples are taken. This method is used in the construction of light wooden buildings and structures.

The probe is lowered into a well 5 m deep. During the capital construction of stone or brick houses, serious geological exploration is required. At the same time, the depth of measurements is 8-10 m. The wells for measurements are located at the corners of the future structure. There should be at least four such soundings (wells). Determine the indicators of the composition of the soil and the depth of its layers; level, amount and composition of groundwater. Another indicator is needed - this is the freezing point of the soil.

The upper layers of marshy soil are mainly peat. Clay and sandstone may follow. Peat is a porous, absolutely loose material with low compressive strength and increased instability. With a small layer thickness, peat is removed and the base of the foundation is placed on the lower hard rocks. This is a shallow base. Its feature is the location of the slab under the foundation above the freezing point of the soil. This base is suitable for light buildings.

A shallow foundation is arranged so that it can rise and fall slightly during the heaving processes occurring in the ground. Thanks to this, it does not crack and retains its shape. This foundation does not apply to brick and stone houses. If the peat layer on the construction site is deep enough (more than 5 meters), it is necessary to apply foundation reinforcement with piles.

Not only the peat layer is a problem when building a foundation on swampy soil. The second problem is close groundwater. There are two ways to deal with this problem:

• lower the water level
• raise the area.

The drainage system helps to significantly reduce the level of groundwater. To drain water from the construction site, trenches are dug to a depth of about two meters, the entire drainage system is led to drainage wells. A layer of rubble is poured into the trench, drainage pipes are laid on it. Drained water from wells is pumped out by submersible pumps.

To raise the site, it is necessary to make an embankment of stone and sand. To do this, remove the upper, weak layer of soil and cover the site with a layer of stone and sand. Such an embankment is carefully compacted and rammed with rollers.

Slab foundation installation technology

The slab foundation must be made in accordance with all standards according to the following basic scheme:

1. Removal of the soil layer. Depth 1 m.
2. Making an embankment (cushion) from a mixture of gravel, stone and sand. Compaction of the embankment and concrete preparation is done.
3. Coating with waterproofing and thermal insulation.
4. Making a frame from reinforcement. Tying the frame with wooden blind areas.
5. Pouring concrete over the frame and its subsequent compaction with an industrial vibrator.
6. Leveling the surface with a rule.

The scheme of installation of the slab foundation

Pile foundation installation

The main thing here is piles. They can only be reinforced concrete and combined. There are three types of piles:

• screw metal;
• driven reinforced concrete;
• bored.

Bored piles with asbestos-cement formwork are mounted only when draining the supporting soil layer. They have a fairly good bearing capacity. Screw metal piles are somewhat inferior to bored piles in terms of their bearing characteristics, but they have high installation qualities: quick and easy installation, ease of transportation.

Scheme of the foundation of bored piles

A distinctive feature of screw supports is the ability to build them up to the required length. Driven piles are installed using pile driving equipment. At the same time, it is not always possible to use heavy equipment in individual construction.

The main criteria in calculating the number of supporting piles are the type and magnitude of the load. Regardless of the variety, piles can be installed in the following order:

1. Rows under the walls.
2. Alone under support.
3. Bushes under the columns.
4. Fields with strong vertical loads.

All calculations of the length and volume of piles are performed according to geological survey data in accordance with building standards and regulations. The lower ends of the piles should rest against dense soil. It should be noted that on each of the considered grounds, any residential building in a swampy area can be installed. Any of the building technologies is suitable for building a house, restrictions can only be related to the operating conditions of the building being built.

In conclusion, it should be noted that not all building materials are applicable for buildings in wet areas. For example, at high humidity, it is not recommended to use foam concrete, expanded clay concrete, aerated concrete due to the strong hygroscopicity of the material. The beam is also not the best material. On swampy areas, it is best to build brick, stone or frame houses. But the most important thing is to lay the foundation correctly and absolutely accurately. To a greater extent, it is thanks to this that a house built according to all the rules will last a long time and reliably.

How to build a garage in a house with a foundation in sims 3?

Non-drying marshy soil with moisture-loving vegetation that can be systematically moistened is not the most favorable place for building a house frame. The close location of groundwater creates seasonal fluctuations in soils, especially during the period of spring warming. Modern construction technologies can solve the problem of how to organize a foundation in a swamp so that it can withstand the load of a house.

Soil analysis

What is swampy land? This is an area with a porous structure, which is 90% water. The rest of the percentage is formed by randomly located particles of minerals - peat, sand, clay. The unsystematic order of occurrence of rocks does not allow calculating the load on the soil.
Soil surveys on the site will help to identify the following characteristics of the terrain:

• type of soil massif;
• groundwater volume;
• freezing depth;
• distance of the aquifer from the surface.

The data obtained make it possible to determine the physical properties of the layers, their thickness and depth, and to characterize changes in the soil over the past few years. On the basis of geological expertise, it is possible to choose which foundation to build in the swampy area.

How to explore the soil yourself?

It is not advisable for summer residents to delve into the details of geodetic surveys. Private developers need to carry out a number of simple measures:

• selection of earthen material from four wells. The drilling depth is 5 m for wood structures, 8 m for overall stone buildings. It is better to probe the surface in the spring, when it contains the maximum amount of moisture.
• mechanical analysis is carried out by sampling a small piece of earth. It rolls out in the hands and bends into a ring. The decayed element testifies to sandstones, unstable - to loams, dense - to clay;
• vegetation inspection. Wild rosemary, blueberry, sedge, cloudberry, horsetail and other crops are present on excessively moist marshy soils.

Research and determination of the type of soil provide for the determination of the change in GWL.

When does the groundwater level change in a swamp?

The volume of groundwater varies throughout the year. During the thaw period, their number increases significantly. The lowest GWL was recorded in winter. A high aquifer imposes restrictions on the construction of a frame in a swampy place. Moisture concentration at the level of 2 meters or less poses a threat of flooding of trenches, pits, mold in the house, basement. A clear algorithm of work will help minimize the impact of springs on the life of the foundation.

pile frame

Base designed for wetlands. Supporting elements - piles that are driven into the soil. A pile foundation in a swamp allows you to solve the problem of heaving, instability of the upper layer of the earth, and allows you to smooth out the unevenness and inclination of the territory.
The advantages of the building:

• low-cost, not labor-intensive process (in 2 days you can build a supporting structure);
• mounting the frame reduces the amount of land work: garbage disposal, digging a pit, concreting;
• the choice of building material for piles: wood, steel, reinforced concrete;
• increased strength, long service life.

It is rational to use a pile foundation in swampy, unstable terrain with a high level of groundwater. There are several limitations to consider when choosing a support structure:

• weak bearing capacity in horizontally mobile soil;
• additional financial costs for the arrangement of the basement (filling voids).

The average depth of the well pit is 10-15 m. To mount the pile frame at a high groundwater level, use poles with a length of at least 25 m. You need to drive the piles until they fit snugly against the ground.

Algorithm of work on the construction of foundations on piles

Construction work is allowed at any time of the year.

1. We treat the tongues with an antiseptic to prevent the development of corrosion.
2. We immerse the piles in the ground: we screw the driven piles, for the screw ones we use a special lever.
3. Cut off the excess protruding part.
4. We fill hollow pipes with cement.
5. Using an electric welding machine, we mount the support platforms on the edged parts of the piles.
6. We process the surface with a waterproofing solution.
7. We connect the structure along the heads with a horizontal grillage.

High speed of erection, resistance to soil vibrations allow to increase the service life of the structure.

slab foundation

The construction was widely used for the construction of a monolithic stone building. Concrete slabs are resistant to temperature changes and loads.
The problem of a high level of groundwater is solved with the help of a sand and gravel pad located at the base of a monolithic slab, buried to the level of soil freezing. Rocks let spring streams pass below the place of occurrence, which prevents deformation. The sequence of technological steps will create a solid slab foundation in the swamp.

1. We prepare the wetland, clear of vegetation, debris.
2. Burlim wells in the corners of the future structure.
3. We dry the trench. At GWL up to 2 meters from the surface, use pumps, from 2 and below - limit yourself to the drainage system.
4. We will strengthen the bottom of the pit with an embankment of sand and gravel. This will protect the foundation from groundwater. From above we form a flooring from roofing material.
5. We make formwork from lumber.
6. Along the entire perimeter of the shaping structure, we mount reinforcement from metal rods.
7. In several approaches, we fill the trenches with a concrete mixture. The thickness of each layer should not exceed 0.2 m.
8. Dismantle the form for laying concrete after the mortar dries (it will take several days).
9. We process the vertical and horizontal surface of the frame with waterproofing mastic.

The foundation in the swamp of monolithic slabs is an expensive type of construction. Changes in soil heaving will not affect the reliability and strength of the frame. Therefore, the tiled foundation is mainly used for swampy terrain.

Tape base

A shallow foundation for a house is suitable for building small timber frame structures. The peculiarity of the type of supporting structure is that the depth of the masonry is higher than the level of soil freezing. When equipping the tape, you need to take into account a number of nuances:

• the role of the drainage system is performed by a pillow of sand and gravel.
• during heaving of the soil, the reinforced frame rises slightly, however, the use of monolithic technology allows you to maintain its shape and prevents the appearance of cracks.
• at the design stage, soil features should be determined. This will allow you to calculate the effect of loads on the future building, to determine the margin of safety.
• the sequence, the technique for performing the work of arranging the foundation, which is located in a swampy area and is relevant with high groundwater damage, is identical to the laying of a large deepening tape - digging a foundation pit, forming a pillow, building formwork, reinforcement and layer-by-layer pouring of cement mortar.
• it is advisable to install a channel for water drainage along the entire perimeter of the foundation at a distance of 1.5 - 3.00 m.

Ease of installation and low cost make the tape popular as a foundation on swampy soil.
Dampness, moisture have a destructive effect on the frame. It is difficult to predict how soil density will change over time. Use waterproofing systems to avoid the effects of heaving on the ground. When choosing the type of foundation that will be located in soft marshy terrain, be guided by the climatic conditions of the area, the type of structure and budget.

Organic soils, including swampy ones, are considered the least suitable for capital construction. This is due to the high moisture saturation of soils, their friability, and the tendency to deformation. However, modern foundation construction technologies make it possible to achieve the stability of the structure and its durability even in swampy areas.

Peculiarities

A feature of marshy soils is the tendency to deformation, instability due to the large number of fine-grained particles, and high levels of moisture saturation. During the off-season, such soils are subject to severe heaving, and in winter - freezing. The high moisture content in the soil causes the formation of dangerous quicksand. All this causes the soils to weakly resist compression, and it is necessary to look for non-standard solutions for the foundation design.

In each case, the decision in favor of a particular system is made on the basis of soil analysis., soil layers directly under the construction site, groundwater level. The method of drilling wells is used as a way to obtain the necessary data. It is recommended to do them in winter, when the moisture saturation of the soil is maximum.

A feature of building a house on wetlands is not so much the difficulties associated with the technical difficulties of construction as the laboriousness of geological surveys, the organization of drainage and other additional work.

Swampy include all types of highly compressible soils:

• clay soils with a porosity of about 52% and loams with a similar indicator of more than 50%;
• loose sandy soils and sandy loams, characterized by high water saturation and porosity over 41%;
• peaty (containing less than 50% organic soils) clay and sandy soils;
• silt - highly porous (up to 60% porosity) soil containing a large amount of moisture and formed under the influence of microbiological processes in reservoirs;
• sapropel is a type of silt containing a high percentage of moisture, having a porosity of more than 75%, containing less than 10% of organic components.

Under highly compressible swampy soil there is always weakly compressible soil suitable for construction.

Several foundation systems are most widespread in wetlands.

Strip foundation with powerful drainage from the basement and drainage

In some cases, this type of foundation can be used on swampy soils with a high content of coarse sand, provided that there are no aquifers under the foundation, as well as springs and other sources nearby.

pile foundation

Most often, this type of foundation is the only possible option for marshy areas. It is suitable even for soils that are eroded to a state of wet slurry. In such cases, the piles rest on solid layers of soil at the bottom of the swamp.

floating foundation

It is a monolithic slab that is able to change position along with the soil, but not deform. Due to the design features, such a system has another name - a slab base.

Suitable for unstable viscous and dense soils, but only on condition that they are not flooded by seasonal floods or precipitation.

Mounting Features

Regardless of the chosen foundation construction technology, its installation on weak, moving layers is unacceptable.

To strengthen them, resort to the following methods:

• peat removal - that is, the replacement of weak (subject to heaving) soils with a non-porous layer, for which, under the foundation, part of the moving layer or its entire thickness is replaced with a pillow of denser layers;
• soil compaction under the base;
• creation of an embankment from non-rocky soils for the construction of a foundation on it.

When creating a foundation in a swampy area, it is important to make the foundation in such a way as to reduce the specific pressure of the object on the ground and thereby prevent it from settling.

With all the variety of construction options, a thorough analysis should be carried out. It is better to draw up several drawings and estimates for different building options. As a rule, for the same area, you can choose at least 2 design options, for example, excavate the entire depth of soft soil and install a strip foundation, or create an embankment and combine it with a pile foundation. Project documentation will allow you to see the strengths and weaknesses of each technology, the cost of objects and make the best choice.

It is important what material the house is built from. For the type of soil under consideration, it is better to use light building materials. The construction of a support for a wooden house, a frame object will be cheaper and less laborious.

In addition, the elasticity of the wall material should also be taken into account - with possible deformations of the soil, wooden structures will retain their integrity to a greater extent than, for example, fragile aerated concrete.

Strip foundation

Usually, the owners of plots located in the floodplain or lowland resort to its construction, so waterlogging of the soil is associated with the proximity of a water source.

As a rule, in this case, a classic strip foundation is used, performing the following types of work before installing it.

• organization of a powerful drainage system with the help of hydro-drainage barriers, which prevents the penetration of moisture into the site;
• the perimeter around the foundation should be equipped with highly efficient soil drainage, having achieved the adjunction of this system directly to the base.

For construction, you should choose the highest point of the site. At the stage of geological surveys, one should make sure that there are no underground keys characteristic of such an area. If any are found, the use of a strip foundation should be abandoned.

But even in the event that such sources are not found, only small one-story houses, mainly made of wood or analogues of the frame type, can be erected on swampy areas under a strip foundation.

After digging a trench, you should first create a sandy, and then a soil (from non-porous soils) “cushion” in it, arrange a formwork, which should be poured with concrete mortar. It is unacceptable to use a strip foundation made of blocks in a swamp.

If the house is built of concrete blocks, then the masonry is reinforced, and a monolithic reinforced concrete belt is installed at the floor level.

pile foundation

Suitable for the construction of even large (one or two floors) houses made of heavier materials (cellular blocks, brick, hollow stone) in a swampy place. This property is due to the high bearing capacity of reinforced concrete foundations, which are based on rocky or hard layers of soil, usually located at the bottom of the swamp. With differences in the height of the relief, bases of different heights are used.

As a rule, the depth of laying supports is at least 6-7 m., bored technology is used. This means that it will not be possible to do the installation with your own hands, it is necessary to attract special equipment. This factor, as well as a number of others, determines the higher cost of a pile foundation compared to a strip foundation in marshy areas. On solid soils, the strip foundation is significantly superior to the pile foundation in terms of labor intensity and cost.

In rare cases, the depth of the hard layers of soil is 2-3 m, then screw piles can be used instead of bored piles. They are less expensive and can even be mounted by hand.

When organizing a pile foundation, the upper layer is usually removed to a depth of 60-70 cm, and instead road geotextiles are laid. The latter is covered with a sand-gravel mixture. The pile heads are connected with a grillage or double channels.

slab foundation

In the presence of a solid topsoil, which is often found on peat bogs and lake residues, it is much more rational to mount a slab foundation. Its main advantage is high strength and lack of roll even with significant soil deformations or rising groundwater levels.

Building a foundation is always fraught with difficulties and serious financial costs. In some cases, home owners pay for the foundation up to a quarter of the cost of the entire construction of the house. And yet, in no case can you save on the foundation. Still, it is on him that the load from the entire structure falls. So any attempt to save on quality can lead to the most unfortunate consequences.

An example of a finished monolithic foundation

However, in some cases, building a foundation is even more of a challenge than usual. Of course, we are talking about the foundation on swampy soil. This soil has a number of disadvantages. Firstly, it is a low bearing capacity - under significant loads, the soil simply parted, and the structure collapsed.

Secondly, these are seasonal fluctuations in ground level. Most often this happens in the spring, when due to the melting of a large amount of snow, the groundwater level rises significantly.
In this regard, special requirements are imposed on the foundation in swamps. Not everyone can answer them.

It is a number of soil imperfections that make many seriously think - what kind of foundation in a swampy area will best solve all problems? After all, if the foundation was chosen incorrectly, after changing the ground level, the building can simply be destroyed.

In addition, after a few years, the building may simply begin to go underground from its own gravity. Therefore, the solution of this problem should be approached as seriously and responsibly as possible.

Fortunately, today there are several solutions to this problem. Yes, you can decide for yourself which swamp foundation best suits your requirements and financial capabilities.

1. . This is a great solution if you need to complete the foundation in the shortest possible time. The main elements are piles - reinforced concrete or bored. With the help of special equipment, they are laid to a great depth - most often about 10-12 meters, but in areas with especially difficult types of soil, this depth can reach 20 and even 25 meters! Having passed to such a depth, the pile simply pierces the swampy layer of soil, resting on a solid foundation.
   Scheme of installation of a pile foundation

   This makes the foundation and the entire structure of the house completely immune to seasonal fluctuations in the level of the soil - the foundation acts as a support for the piles, the level of which does not change depending on the season or precipitation. It is important that all the work can be done in two to three days. Installation cost is relatively low. You can install such a foundation both in summer and in winter. Pile foundations in swamps have proven themselves well - reliable, durable and unpretentious, they have collected thousands of positive reviews from different parts of our country.

2. . The most expensive and difficult to manufacture. And yet, in the northern, marshy regions of our country, it is monolithic or most often used in the construction of private and multi-storey buildings. It is one huge, monolithic slab, deepened to the level of soil freezing.
   One of the options for a monolithic foundation

   Even if the ground around is heavily heaving, this in no way affects the reliability and safety of your foundation. The large weight of the slab (tens of tons!) excludes the possibility of raising the foundation, which could lead to the destruction of the house. High strength allows a monolithic foundation to withstand without harm to huge loads in compression, bending and tension. Therefore, it is it that is most often used in construction in the swampy regions of our country, despite its high cost.

3. Shallow foundation. It occupies a niche between a pile and a monolithic foundation, both in terms of cost and construction time. Such a foundation in a swamp has also proven itself well.
   Diagram of a shallow foundation device

   However, it should be borne in mind that a shallowly buried foundation is only suitable for - or. The fact is that the relatively small thickness of the foundation does not allow it to withstand significant compressive loads. At the same time, it perfectly resists the loads from heaving of the soil. Since it is also monolithic, under heavy loads from the soil, it simply rises or falls slightly, like the whole house built on it. This, combined with low cost and speed of manufacture, makes this type of foundation in swamps quite popular.

As you can see, people who decide to build a house even on problematic, swampy soil have a fairly large choice. However, some of them do not want to spend extra money, preferring to build a foundation in a swamp with their own hands. Is it possible?

What foundation is easier to build with your own hands

Many of our compatriots prefer to do the construction of any complexity with their own hands. First of all, because it makes it possible to save a lot of money. Of course, there are no exceptions when they need to build a foundation in a swamp. So it will be useful to consider the possibility of building different types of foundations on your own.

First, consider the pile foundation. Alas, it is almost impossible to build it on your own, without the involvement of specialists. The fact is that only specialists have information about the thickness of the swampy layer in a particular area. In addition, they have heavy equipment at their disposal, which makes it possible to easily and quickly screw piles to a depth of 10-20 meters.

Therefore, you should not even try to cope with this work on your own. Fortunately, this does not apply to a monolithic and shallowly buried foundation. In this case, the work may well be done on its own, which will reduce construction costs by several times. And even though you will need to rent a concrete mixer and possibly use the services of a bulldozer, the savings will be very tangible.

Building a monolithic foundation yourself

So, you have decided to build a monolithic foundation. Where does it all begin?
Of course, from the markings on the ground. For construction, it is best to choose the second half of summer - at this time the groundwater level is close to the minimum, it rains relatively rarely, and warm air will allow the concrete to harden in the shortest possible time, without the use of special building additives, which are quite expensive.

You can start building the foundation only when you already have a finished house project.

In this case, you know exactly what the dimensions of the building will be and, accordingly, the dimensions of the foundation. It is desirable that the foundation on all sides protrude beyond the perimeter of the house by 30-50 centimeters.
With the help of pegs and a nylon cord, you need to designate a specific place where the foundation will be located.

Now it is necessary to remove the soil to a depth of 1-1.5 meters. The specific level of the foundation depends on the depth of soil freezing, this indicator can be found in any construction company.

Of course, during earthworks, many tens of cubic meters of earth will have to be removed. It is simply impossible to perform such a volume of work manually with a shovel. Therefore, a reasonable step would be to rent an excavator and a truck to remove all or part of the soil. Yes, you will have to pay a large amount. But you will save several weeks of continuous work.

The bottom of the resulting pit must be covered with rubble and evenly distributed. The thickness of the rubble layer should be 20-30 centimeters. After that comes the same layer of sand, which is also carefully distributed and compacted.

This step should never be skipped.

Sand and gravel pillow allows you to solve several problems at once:

• uniform distribution of the load from the foundation and the house along the bearing soil;
• reducing the effect of heaving in the winter season;
• rapid removal of moisture after precipitation or snow melt from the foundation.

When the sand and gravel cushion is ready, a reliable waterproofing must be laid on top of it. Ruberoid is best suited for this. Yes, it is much more expensive than conventional construction polyethylene. But it is more durable and efficient, and is also able to withstand significant tensile loads and not tear.

Sheets of roofing material should not only cover the entire bottom of the pit, but also the walls to a height of at least 30-50 centimeters. The purpose of waterproofing in this case is twofold. On the one hand, the roofing material layer does not allow groundwater to come into contact with concrete before it gains sufficient strength.

On the other hand, it excludes the possibility that "concrete milk" will be absorbed into the ground, due to which the strength of the monolithic foundation will be reduced.

The next stage is the preparation of the frame from the reinforcement. To do this, you will need fittings and knitting wire or a welding machine. A frame of appropriate dimensions is constructed from the reinforcement - it must cover the entire volume of the future foundation, thereby allowing the concrete to withstand significant bending and tensile loads.

The installation of the frame can also be done manually, but in this case it will take quite a lot of time to work.

Therefore, it is better to use a special knitting gun or welding machine - you will save at least one working day.

When creating a frame, consider the fact that the reinforcement should be not only at the bottom of the foundation, but also at the top. The walls of the pit must be covered with formwork - ordinary thin tin or plywood will do.

The main thing is to ensure reliable isolation of liquid concrete from the ground, from which it can take water.
After that comes the turn of concrete. It is best to use concrete grade M400 or M500 for this. Yes, you will have to overpay at least a few thousand rubles. But you will be sure that the foundation will be able to withstand huge loads without the slightest harm to itself and, accordingly, to the house that will be built on it.

It is worth recalling that you will need tens of tons of concrete to fill the foundation. So, it makes sense to spend money and rent a concrete mixer. In this case, you can get a large amount of concrete in a short time. It is not necessary to pour concrete in several steps when the bottom layer has already set - the foundation will not turn out to be monolithic, and even small gaps in its structure will lead to the fact that its technical characteristics will decrease significantly.

When the pit is filled with concrete, it must be compacted using special equipment - constant vibration allows you to fill any gaps with concrete and get rid of air bubbles in the foundation structure. Such bubbles can significantly reduce the strength of concrete.

After compacting the concrete, you need to leave it for three to four weeks so that it grabs and gains sufficient strength. The setting time depends on many factors - air humidity, ambient temperature, foundation thickness and others.

Be that as it may, after a month you will receive a monolithic foundation that can easily serve you for many decades, withstanding any kind of load and without losing its original strength.

That's all. Now you not only know which foundation is best for building houses in marshy areas, but, if necessary, you can do all the required work yourself.