We draw up the correct foundation plan. Do-it-yourself foundation for a house Rules for planning a foundation for a house

The strength and durability of the future home depends on the reliability of the foundation for the house. Any mistake made at this stage can lead to costly repairs and reduced service life of the entire house. Long before the start of construction work, you should find out:

• choice, and how its type depends on the material of the walls of the house;
• How to choose a house foundation design depending on the type of soil on the site;
• What types of foundations are there for a private house and what is the force of frost heaving?
• What to do if the site has so-called difficult soil and a high groundwater level.

Choice of foundation. Where to begin

Before you start choosing a foundation, you need to understand why it is needed and what function it performs.

Roman Nikonov Construction consultant

The foundation is the laying between the building and the ground. It distributes the weight of the building onto the ground. It is not a static structure - it can shrink, bend, and sometimes stretch. To prevent the house from deforming on it, two conditions must be met:

• The ground precipitation under the house should not exceed certain values. They are calculated using special formulas depending on the weight and design of the building, the type of soil, its humidity and porosity. These values ​​are determined from samples obtained during engineering geological surveys;
• The soil should not change its structure. For every soil that is under ever-increasing load, there comes a time when its particles begin to break or shift relative to each other and it sags. This means that there is pressure under the sole at which the base soil “breaks.”

Site layout

When choosing a site for their future home from several options, many developers are guided only by price, area and the presence of utilities. But, as practice shows, one of the decisive factors when choosing a site for future development, and therefore foundation work, should be the possibility of competent planning of the territory.

Andrey Pashukhin. Company construction engineer Fundamentally. RF

It is advisable to choose a site for a house in accordance with your understanding of how you plan to use it subsequently, namely, what kind of house and outbuildings will be built on it.

Already at the initial stage, you need to look at whether the site is suitable for your needs, and not try to build a house on a completely unsuitable territory.

If you initially plan to build a large stone house with two or three floors, then the appropriate site must be selected. It should be at least 10-15 meters larger than the boundaries of the house and have soil with good bearing capacity.

You need to clearly understand that the more complex the geology and soils on the site, the more expensive it will cost to build the foundation of the house. The design should be based on a feasibility study of the house design and geological surveys to determine the type of soil.

The main factors that determine what the design will be are as follows:

• Characteristics of the future house and its design features;
• The material from which the house will be built;
• Type of soil and slope of the site;
• Groundwater level and soil freezing depth in winter.

The heavier the house and the more complex its design, the more complex the foundation and the more expensive it will cost.

Soil as the foundation of a house

• Versatility.
• Reliability.

It does not require much penetration into the ground, which is especially important when the groundwater level is high.

Minuses:

• For large private houses of complex shape it turns into a very complex structure.
• A lot of materials are required, especially taking into account the sand cushion and floor backfill.
• Requires a separate base structure, as it is usually located at ground level.

Such a foundation is inconvenient to build for houses on slopes with a height difference of more than 1 meter over the entire length of the house.

Tape

Divided into two main types:

• Fully recessed.
• Shallow - MZLF.

Fully recessed – is done to the entire depth of soil freezing. This is a calculated value that takes into account the type of building, soil, and mode of operation of the house.

One of the most reliable types of foundation for a house of any shape, weight and area. What is important is that the bearing capacity of such a foundation is almost independent of its reinforcement.

Pros:

• Easy to manufacture.
• Reliable.

Minuses:

• Very high material consumption, since it requires laying below the freezing depth.
• Difficulty in designing at high groundwater levels.

Shallow the foundation is a monolithic reinforced concrete beam on a sand cushion.

Roman Nikonov

This type of foundation was developed in the 60s of the 20th century, when it turned out that the load-bearing capacity of a fully buried strip for lightweight houses is excessive; moreover, frost heaving sometimes breaks such foundations if they are made in violation of technology (poured into the ground without formwork).

Pros:

• Construction requires less material than a fully buried strip.
• Such a foundation is possible at high groundwater levels.

Minuses:

• Low rigidity (cases of cracks forming in the structures of houses made of small-piece materials - blocks and installed on such foundations are very common).
• High requirements for the quality of reinforcement.
• Mandatory installation of drainage and sand cushion.

If an MZLF is being laid, then an insulated blind area must be installed. This will ensure a stable position and prevent soil heaving. In other cases, it is sufficient to install a non-insulated blind area to drain rainwater from the foundation to prevent flooding.

It is important to remember that already at the foundation design stage it is necessary to think about the fact that the presence of a large slope Location on will require “anchoring” and leveling measures, and the presence of groundwater at a high level will require its lowering and diversion.



Alexander Zemskov

Very often there are areas with a significant slope, on the one hand this is a plus from a design point of view, here you can build an interesting landscape design. But such a site, compared to a flat one, is more expensive to build a foundation.

Thus, choosing a foundation for a house involves solving many different problems, and when designing, it is necessary to take into account a whole range of factors that influence the durability of the foundation, and therefore the reliability of your future home.

FORUMHOUSE has collected everything possible.

We offer you a detailed and visual story from a member of our portal. Here you will find everything.

An obligatory part of a residential and industrial building is the foundation for a house. It ensures stability, reliability, and a long service life of the building. It is important to thoroughly study before starting construction how to build a foundation for a house, as well as study the design features and purpose of various types of foundations. Foundations are constructed in strict accordance with technology requirements. Let us dwell in more detail on the sequence of actions for their construction.

Foundation for a house - types and features of foundations

The design features of the foundations allow them to be used as a reliable base for various buildings. Choosing a foundation design is a serious task, solved based on an analysis of a set of factors. It should be taken into account that the choice of the optimal option is influenced by natural factors, as well as the mass and design of the future building.

The foundation of any structure is its foundation, on which the future of the constructed object depends.

The following types of foundations are widely used in the construction industry:

• columnar. It is not difficult to build it for wood or on your own. A distinctive feature of a columnar foundation is that it allows the construction of buildings on areas with a significant slope. Supporting elements are located at the intersection points of the walls, as well as evenly along the entire contour of the building. With such a device, the base does not allow for the construction of a basement. The design has proven itself positively in problem areas. The columnar base ensures the stability of buildings located in areas with increased soil freezing depth;

• tape The reinforced concrete base of the structure follows the contour of the building and is concreted with a kind of tape. Professional builders know how to make a strip foundation for a house. It is important to construct a strip foundation on soils with deep aquifers and an insignificant freezing depth. Brick houses, block buildings, utility structures, as well as fencing structures should be located on strip foundations. Massive structures made of heavy stone should not be built on a strip base. The design of the strip foundation allows for the arrangement of a basement. You can build the foundation yourself or use the services of professional builders;

• slab If it is necessary to make a reliable foundation for a building located on problematic soils, a slab option is used. Structurally, the slab foundation is a massive concrete slab reinforced with a reinforcement frame made of steel wire. Slab construction is characterized by an increased level of costs, which pays off over the long-term operation of the structure. To ensure the required safety margin, it is necessary to perform strength calculations and evaluate the load capacity of the slab base;

• pile-screw. Increased load capacity, short duration of installation activities, as well as an affordable price are the main features of a foundation on pile or screw supports. The pile-screw type foundation is widely used in areas with various types of soil, with the exception of rocky. A significant disadvantage of the pile-screw base is the gradual destruction of steel supports as a result of the negative influence of corrosion processes.

When thinking about how to make a foundation for a house, study in detail the types of foundations, their design features, and also consult with professional builders.

How to make a foundation for a house yourself

Installation and installation of the foundation for a house is a responsible set of activities carried out according to a specific algorithm. When we build a foundation for a house, we must follow the technological sequence of operations and be guided by the requirements of the project.

The main stages in the construction of the foundation base:

1. Performing markings.
2. Excavation works.
3. Construction of formwork structure.
4. Assembly and installation of reinforcement cage.
5. Pouring concrete solution.
6. Compacting the array with deep vibrators.

Please note when making the foundation that reliable waterproofing of the foundation will protect the building from moisture absorption and will avoid dampness. Let us dwell on the specifics of the main stages.

Marking the foundation base

The marking operation involves transferring the design coordinates to the actual conditions of the construction site. For marking activities, pegs made of wood and metal, as well as construction cord, are used.

When performing markup, adhere to the following algorithm:

1. Drive pegs along the front part and tighten the construction cord. The interval between pegs driven into the soil should exceed the size of the façade by 50 cm.
2. Mark the coordinates of the location of the corners of the building on the cord and drive in the stakes. Draw marking lines through the marked points, perpendicular to the front of the building.
3. Measure along perpendicular straight lines the distance corresponding to the length of the side walls of the building and make a mark using existing wooden or steel pegs.
4. Stretch a cord between the hammered pegs. The resulting marking corresponds to the external contour of the future house. Check the correctness of the markings using the project.
5. Check the correspondence of the angles by determining the difference in the diagonals. Equal lengths indicate right angles. Deviation of diagonal lengths up to 2 cm is allowed.
6. Mark the inner contour of the foundation line, stepping back from the outer contour into the future foundation by 40 cm on each side. Drive the pegs into the appropriate locations.

The markings performed affect the location of the future structure, its configuration, as well as its strength properties.

Earth events

Excavation work is one of the most labor-intensive operations in the construction process. Earthworks are carried out using various methods:

• manually using bayonet and shovel shovels. The manual method is characterized by labor intensity and requires the involvement of an increased number of workers to complete the task within a given time frame;
• using special construction equipment. Mechanization of earthworks can significantly speed up their implementation, which reduces the duration of the overall construction cycle.

The depth of the formed pit is determined by the type of foundation being constructed:

• the shallow belt base is located 70-80 cm below the zero level of the soil;
• The depth of a standard foundation, depending on the level of soil freezing, can be 160-180 cm.

When healing the soil, pay attention to the following points:

• ensure that the trench walls are vertical;
• install, if necessary, supports to prevent the soil from collapsing;
• Level the bottom of the pit and check horizontality using a level.

The cushion of crushed stone and sand provided for by the project requires an increase in the depth of the trench by 15-20 cm.

The procedure for constructing crushed stone-sand bedding:

1. Pour sand onto the base of the pit, ensuring a layer thickness of up to 15 cm.
2. Moisten the sand mass and compact it thoroughly.
3. Re-fill with sand and provide additional compaction.
4. Place a layer of crushed stone 15-20 cm thick on the sand and compact it.

Laying geotextile fabric on the bottom of the pit will prevent siltation of the gravel-sand backfill for a shallow foundation.

Installation of formwork for the foundation

The installation of panel formwork requires special training. It is important to decide on the choice of building material that can withstand the load from the weight of the concrete mixture.

For the manufacture of formwork the following is used:

• edged wood 2-2.5 cm thick;
• moisture-resistant plywood;
• sheet steel.

The use of plywood and boards, which have a low price, allows you to reduce costs.

Sequence of actions for installing formwork:

When installing the formwork, pay special attention to the rigidity of the panel structure and the absence of cracks.

Reinforcement is a prerequisite for building a good foundation

A spatial frame made of steel reinforcement, laid in the foundation, increases its strength and ensures durability. To make the frame, rods with a cross section of 1-1.6 cm are used, connected with annealed wire.

Frame assembly procedure:

1. Cut the rods into pieces of the required sizes.
2. Tie the rods into a flat lattice using tying wire.
3. Assemble a frame from two flat gratings using transverse rods.

Place the assembled frame on special supports that guarantee a fixed distance to the concrete surface.

Pouring the foundation for a house yourself

Before starting concreting, mark the level of pouring the mortar inside the panel formwork. The use of concrete produced at specialized enterprises allows us to produce a foundation with increased strength. When we make the foundation, we use a concrete solution based on M400 Portland cement, fine gravel and coarse sand.

Prepare the solution using the following technology:

1. Prepare ingredients in proportions appropriate to recipe.
2. Mix sifted sand with crushed stone and Portland cement.
3. Gradually add water until desired consistency is achieved.
4. Mix the solution thoroughly until smooth.

The order of the stages of pouring the foundation:

1. Fill the concrete solution with a twenty-centimeter layer.
2. Check the filling of voids in the reinforcement grid.
3. Add the rest of the concrete.
4. Remove air inclusions with reinforcing bars.
5. Compact the concrete mass with a vibrator.

After concreting is completed, level the surface with a rule or trowel. Dismantle the formwork after the concrete has completely hardened.

How to build a foundation for an extension to a building

When thinking about arranging the foundation for an extension, adhere to the following recommendations:

• maintain equal depth of the foundation of the attached structure and the main building;
• ensure a rigid connection between the reinforcement grid of the main building and the frame of the extension.

Pouring is carried out in the same way as the main foundation.

When planning to build a foundation for a house from expanded clay concrete blocks or other building materials, it is important to decide on the type of foundation and also study the technology. Knowing the technological nuances, it is not difficult to make a concrete or utility building. Professional builders will tell you, if necessary, how to properly fill a residential building. The foundation can be used as a foundation base and can be easily found on our construction portal. The construction of a foundation is a responsible process in which there are no trifles.

Any house is built strictly according to the project, which is developed by specialists. One of the most important points in construction planning is the calculation of the foundation. But some of the buildings have to be built independently. These include bathhouses, garages, gazebos and even small residential buildings. In such cases, it is important to select and design a high-quality and reliable foundation. Moreover, the cost of the foundation from all work sometimes reaches 1/3. If you make a mistake, it is sometimes not possible to redo the foundation of the house, and it is always expensive. And no one will return the spent energy and time. You can learn how to calculate the foundation for a house and choose the right one from this article.

The foundation of a house is primarily the basis for the structure, the quality of which will determine how long the building will last. Any construction of a house made of timber must be built in accordance with the approved documentation, in which the calculation of the foundation is not the least important.

A properly designed foundation will protect the building from flooding and will save the construction of a house made of laminated veneer lumber or any other from cracking and destruction. The platform must be designed to easily support the weight of the house and at the same time distribute the load evenly onto the ground.

The foundation calculation includes:

1. Calculation of loads for various types of soil.
2. Calculation of cubic capacity (determining how many building materials are needed).
3. Calculation of the cost of the foundation, including labor and materials.

The most common mistakes when installing the base can be seen in the video:

Which base design to choose?

In the construction of wooden houses I use the following structures:

1. Tiled.
2. Tape.
3. Columnar.
4. Pile.

There are areas where it is rational to use a mixed type platform, for example, a strip-pile platform. This is a modification of one of the main types. But this is a complex structure and builders are trying to change the composition of the soil to suit one of the main types. This is how the swampy area is drained and sand washed in, or part of the soil is simply removed and covered with slag, which, when compacted, turns into concrete.

The foundation is chosen depending on the house being built. The heavier the structure, the more massive the foundation. To build a house from profiled timber or rounded logs, strip or columnar types are used. Moreover, the tape type is made shallowly recessed.

The depth of occurrence is calculated based on two main factors:

1. Depth of groundwater.
2. Soil freezing in the area of ​​future construction.

There are average standards for the depth of the sole on various soils:

• Sandy loam - 125cm
• Clay and loams - 150 cm
• Sand and gravel - 100 cm

This is the maximum occurrence of the foundation of the house according to the construction GOST, but it also indicates the maximum occurrence indicators:

• For dry soil - 70 cm,
• For wet areas with close groundwater - 120 cm.

If the house according to the plan has basements, then the base of the structure should be at least 40 cm below the floor level.

Each type of foundation has its pros and cons. So, for example, a columnar one is erected in a short time, a strip one is considered one of the most durable due to the rigid connection of the structure both across and along. Monolithic is expensive, it is built in rare cases when the soil is very mobile.

What loads affect the foundation?

There are always two forces acting on the base:

With proper calculation, the foundation must withstand the weight of the house, furniture, residents, snow and wind, as well as pressure from swelling of the soil. When planning, the weight of a building is calculated in accordance with special tables that indicate the approximate weight of a particular material. It’s not difficult to calculate how much a house costs using these tables. The weight of the house should be 1 cm 2 /kg greater than the load that the soil can withstand. So for some types of soil this load is equal to:

• Gravel and coarse sandstone - 3.5-4.5 kg/cm2.
• Fine sandstone - 2-3 kg/cm 2
• Clay hard soil - 3-6 kg/cm2.
• Crushed stone - 5-6 kg/cm2.

When making calculations, one should not forget that the base structure itself also has a certain weight. In any case, design calculations are always individual for different areas and buildings.

All loads on the foundation are divided into permanent (roof, walls, floor beams, waterproofing, etc.) and temporary (snow cover, wind, etc.).

The total load (the house itself, the foundation, the insulation system) and during operation (furniture, people living, etc.) are calculated.

After construction, the house shrinks, and so does the foundation. The soil underneath is compacted and the foundation “sags” - this value is called settlement. If the settlement is uneven, the foundation will quickly crack and fall apart. To avoid this, you need to accurately calculate the area of ​​the foundation and calculate the load on it.

How is the load on the foundation calculated?

Having determined the size of the house, it is not difficult to calculate the area of ​​the foundation for it. This is done to correctly calculate the load. The load depends on what material the house is assembled from. The regulatory construction documentation shows the specific gravity of the foundation depending on various materials:

• Brick and concrete - 1880-2200 kg/m 3,
• Household stone - 1600-1800 kg/m 3,
• Weight of the walls of a wooden house:
• Frame - panel - 30-50 kg/m2,
• Lumber, rounded and chopped logs - 70-100 kg/m2.

To determine the load, it is important to know the weight of the floors:

• Basement floors - 100-300 kg/m2,
• Attic floors - 150-300 kg/m2,
• Reinforced concrete floors - 500 kg/m2.

Roof specific gravity:

• Sheet steel - 20-20 kg/m 2
• Ruberoid - 30-50 kg/m2
• Slate - 40-50 kg/m2
• Ceramic tiles - 60-80 kg/m2.

Let's see how we can use these indicators using a real example:

According to the plan, the future house measures 8x5 with one interior wall. The height of the building is 3 m. In order to find out the length of the walls: 5+8+5=18 m. We calculate the area of ​​the walls: 18x3=54 m2.

To calculate the area of ​​the basement floors, let’s create the product of the length and width of the house: 5x8=40 m2. The attic floors have the same area as the basement floors, which means also 40 m2.

The next step is to calculate the weight and area of ​​the foundation

Foundation area and weight

Calculating the foundation is not difficult, let’s look at a specific example:

For the construction of the house, a strip foundation with a base of 1.5 m was chosen, to this figure you need to add 50 cm above the ground level. The height of the foundation will be exactly 1.50 + 0.50 = 2 m. Then the length is calculated: (5 + 8) x 2 = 26 m. The internal partition has a length of 5 m. 26 + 5 = 31 m.

Let's calculate the volume of the foundation by multiplying the length and height and width. Let's take a width of 50 cm, 0.5 x 31 x 2 = 31 m 2. Now, according to the above data, let's calculate the weight of the foundation: Reinforced concrete weighs 2400 kg/m3, 31x2400 = 74,400 tons. The supporting area of ​​the foundation will be 31,000x50 = 15,500 cm 2.

To determine the total weight of the structure, you need to add the weight of the house with the weight of the foundation and divide it by the resulting supporting area. So we get a weight of 1 kg/cm 2.

If the permissible area for a certain type of soil is higher, then you need to change the width of the platform for a strip one, and the number of pillars for a columnar one. But at the same time, the total weight of the structure will increase, so the calculations need to start again.

How to calculate concrete for a foundation

In order not to purchase unnecessary building materials, it is important to accurately calculate the cubic capacity of the foundation. To calculate the cubic capacity, it is important to take into account two factors: the type of foundation and the complexity of its design. For the convenience of readers, we will consider the calculation of various types of foundations separately.

Calculation of the cubic capacity of the strip base

It is easiest to calculate the cubic capacity of a strip foundation. To do this, you need to add the length, width and height. Let the width be 50 cm, we have already calculated the height above 1.5 m. The length is calculated along the perimeter 5+ (8 + 5) x 2 = 45 m. The cubic capacity is calculated: 0.5 x 45 x 1.5 = 33.75 m 3. We round this data and add 10% (margin), we get 37 cubic meters of concrete.

Calculation of cubic capacity of a columnar base

A columnar foundation can have different shapes (circle, square, etc.). Let us calculate the cubic capacity of round pillars as an example. For this you need the following values: diameter, cross-section, column height. The area is calculated by multiplying the Pi number by the radius x 2. The cross section for a pillar with a radius of 15 cm: 3.14x0.075m = 0.2355 m. Knowing the radius and height, the volume can be calculated: 0.2355x1.5 = 0.353 m3. This number must be multiplied by the number of pillars in the foundation.

Calculation of cubic capacity for a slab base

To calculate a monolithic rectangular slab, you need to know its area and thickness. The planned house has dimensions of 5 x 8, therefore the area of ​​the slab will be 40 m2. Experts recommend using a monolith 10-15 cm thick. We calculate the cubic capacity at 10 cm thickness: 40x10 = 400 m 3 .

On a monolithic foundation, stiffening ribs are made around the perimeter. To calculate their area, you need to know their length and width. In a 5x8 structure, I install stiffeners every 2.5 m. There will be 3 such ribs in width and 4 in length. The total length will be equal: (5x3) + (8x4) = 47 m.

Now let's calculate the cubic capacity. The width of the rib is equal to the thickness of the slab - 10 cm. This means that the area of ​​one rib is exactly 0.1 x 0.1 = 0.01 m2. We multiply the area by the length 47 = 0.47 m 3.

How to determine the amount of reinforcement and wire

To create a rigid and durable structure, iron reinforcement is used in installation. Its quantity depends on the type of foundation, loads and soil. Reinforcement with a larger diameter is used to obtain a platform with a greater load capacity. But the weight of the foundation with reinforcement increases. If the soil is hard, then the foundation will deform minimally, which means that the reinforcement will need a minimum diameter.

Quantity of reinforcement for strip base

The reinforcement for a strip foundation is taken with a diameter of 10-12 mm, since the structure itself can withstand heavy loads. They lay it in two rods, regardless of how deep the base is. Experts recommend laying the reinforcement 10-15 cm from the top pouring point. Vertical rods do not have a load, so the cheapest ones can be used.

For a house measuring 5x8, the length of the strip base is 45 m. With reinforcement of 4 rods, the consumption will be: 45x4 = 180 m. We add transverses with a foundation height of 150 cm and a width of 50 cm in increments of 40 cm: (8/0.4)x0.5 =10 m. Add them to the length: 180+10=190 m.

Knitting wire is needed for one connection 30 cm. Length 45 m and pitch 40 cm: 45/0.4 - 112.5. We multiply this figure by the size of one connection: 112.5 x 0.3 = 33.7 m of binding wire needed for a 1-level foundation.

Quantity of reinforcement for columnar base

To reinforce the columnar base, thick reinforcement from 40 mm is used. Horizontally, the reinforcement does not bear any load, so here you can take the most inexpensive one. On average, 4 rods are used in the frame of one pillar. Knowing the number of pillars, it will not be difficult to calculate the size of the reinforcement.

For a structure 1.5 m high with a diameter of 15 cm, you need 4 rods, with a pitch of 7.5 cm and binders at 3 points. Thick reinforcement needed: 1.5x4=6m. For a thin bundle: 30 cm (for one node) x 3 = 90 cm. If 20 pillars are used in the foundation, then the number is multiplied by this figure.

Knitting wire is needed to connect one rod at 3 points. This number is multiplied by the number of rods and vertical connections: 3x4x30=72 m.

Number of reinforcement for a monolithic base

For dense, stable soil, you can take thin reinforcement from 10 mm. For heavy structures and unstable soil from 14 mm. The ligament is attached in increments of 20 -30 cm.

For a 5x8 platform you need 27 pieces in length and 17 pieces in width. Since a double harness is needed: (17+27)x2=88. This number must be multiplied by the length of the rod to obtain the footage of the reinforcement.

How to calculate the cost of a foundation

After the calculations of the cubes and the amount of reinforcement have been made, it is easy to calculate the cost of the foundation. Work and the price of formwork boards + earthworks and equipment are added to the basic cost.

On average, the cost of a turnkey structure starts from 15,000 m2. But you can save money and do all the work yourself.

The cost of ready-made concrete mortar ranges from 700 rubles per cubic meter, but you can reduce costs by making concrete yourself. To do this you will need sand, gravel and cement M250 or 400. The average price for cement is from 800 rubles. per bag of 40 kg. KamAZ sand costs from 2,500 rubles, it is enough to fill the foundation.

Costs are also reduced when performing partial work, for example, digging a trench and making formwork with your own hands, and entrusting the pouring of concrete to specialists.

In any case, you should not skimp on the foundation of the house, as it must be reliable and durable. And we explained in detail how to calculate and not overpay.

Construction of a private house requires a lot of time and money; it is very important to take into account every detail in its design, especially when arranging the foundation. After all, the reliability and durability of the house depends on it. If the choice of foundation for a house and its construction are made incorrectly, this will cause a lot of problems in the future that are very difficult to solve. In the world of construction, there are different types of foundations, but you should not choose based on the advice of neighbors and friends - it would not be superfluous to consult a specialist in this field.

If the foundation will be built for a brick house, then when choosing it it is important to take into account the large weight of the walls. Otherwise, the constructed foundation, which cannot withstand high loads, will soon cause serious problems, cracks will appear on the walls and then the building may collapse.

Cracks in the wall due to poor quality foundation Source rembud.dp.ua

That is why it is very important to choose the right foundation that can support a lot of weight. Choose from slab, strip, column and pile foundations. Each of them has its own requirements that must be taken into account. Only if they are observed, it is possible to build a high-quality and reliable foundation for housing construction.

What is taken into account when choosing a foundation

The definition of a foundation is that it is the load-bearing part of a structure on which the walls rest. It can also be said that the foundation is the main component of a house that affects its longevity. And if the foundation is cracked, it means that its selection or construction was approached incorrectly. Cracks will inevitably spread to the walls, which will cause the entire house to become unsafe. To avoid this, it is necessary to take into account all factors that affect the strength and durability of the foundation during its construction.

Construction of a rubble concrete foundation on heaving and non-heaving soils Source hozsektor.ru

Soil properties. When choosing the types of foundations for a private house, it is the soil that is taken as the main determining factor. Therefore, before starting construction, it is necessary to order geological studies, during which geologists will take soil samples. After studying the composition of the soil, the following will be identified: groundwater level depending on the season, heaving, and the possibility of subsidence. It is imperative to take into account the seismicity of the construction area.

Foundation loads. This is also an equally important factor when choosing a foundation. The load depends on the weight of the entire house as a whole (load-bearing walls, partitions, roofing and even the furniture with which the home will be furnished). It is also necessary to take into account the supporting area of ​​the foundation; the pressure on the ground depends on it. The support area is defined as the quotient of the weight by the area of ​​support. The lower the pressure, the better, but increasing the width of the foundation entails additional costs.

Example of a monolithic foundation Source monolitspecstroy.by

Laying depth. When choosing the laying depth, it is necessary to take into account the composition of the soil and its humidity, maximum negative temperatures in the winter season, and the groundwater level. Swelling of the soil in winter is the main danger for the foundation, because the frozen soil begins to increase in volume, thereby pushing it upward. But the greatest danger is that this happens unevenly in different places, which can lead to a fracture in the foundation. Good waterproofing and drainage system will eliminate cracking and reduce subsidence.

Quality of material. The main component of the foundation is cement. When choosing it, it is necessary to take into account the storage period and conditions, as well as the brand, which must correspond to the area of ​​application.

In addition to the above factors, the presence of nearby buildings and man-made hazards should also be taken into account. The construction of a new foundation increases the load on the ground, which can negatively affect nearby buildings. An important factor is the choice of a specialist who will help you choose the type of foundation taking into account all the requirements and design it correctly.

Determination of groundwater level and study of soil moisture Source kakpostroit.su

Types of foundations for a private house

Each type of foundation differs in construction technology, characteristics, and conditions of use. For residential construction, the following types of foundations for a private house are usually used:

• tape;

• columnar.

Construction of different types of strip foundations on different soils Source shkolaremonta.info

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

Online foundation calculator

To find out the approximate cost of various types of foundations, use the following calculator:

Strip foundation: what is its difference

Looking at the photo of the foundation below, it immediately becomes clear why it received such a name. The structure consists of strips dug into the ground; they take on the entire load of the load-bearing elements of the house.

The depth of the strip foundation is determined depending on the materials from which it is built. The design of a strip foundation for a private house is slightly different depending on the type of strip itself. There are two main types of strip foundations: monolithic and prefabricated. The first design option is erected immediately on the site, the second is assembled from reinforced concrete blocks. They are produced in factories, then brought to the construction site and, using specialized equipment, a prefabricated strip foundation is erected.

Source journal.n1.ru

A monolithic strip foundation is a reinforced concrete structure that is superior to the prefabricated type in terms of reliability and durability, since it is more resistant to deforming loads and is practically not subject to erosion by groundwater.

A prefabricated type of strip foundation is built not only from blocks, but also from rubble stone - rubble concrete (consists of concrete and boulders). Also a prefabricated type is a brick foundation; it is used for the construction of houses of no more than five floors.

Strip foundations are classified into two types according to their depth: shallow and deep structures. The base of shallow strip foundations is placed above the freezing level of the soil - at a distance of 30–80 cm from its surface. Deep foundations are deepened by 1.5–2 m, that is, the base is located below the freezing line of the ground.

Shallow strip foundation Source doka-metal.ru

Shallow strip foundations are suitable for the construction of houses of no more than two floors, provided that the soil at the site of construction is not prone to heaving. But deep foundations can be used in soils prone to thermal expansion.

The main advantage of strip foundations is the relatively low construction costs, with the exception of prefabricated structures made from foundation blocks, since their cost is quite impressive.

Strip foundation made of blocks Source t-spectr.ru

Pros and cons of strip foundations made of FBS blocks

Advantages:

short construction time (in the presence of competent specialists and special equipment, a strip foundation made of blocks is built much faster than a monolithic one);

the blocks are made of high-strength concrete in accordance with all standards, so the foundation from them is frost-resistant and can withstand heavy loads;

each product has a stable geometry;

some blocks have grooves that increase the strength of the structure;

Suitable for installation on any soil.

Video description

For more information about the block foundation, watch the video:

Flaws:

high price (unlike a monolithic foundation, such a foundation will cost much more);

installation of foundation blocks requires the creation of high-quality waterproofing and sealing of seams;

installation is possible only with special equipment;

a high-quality base for laying blocks is required;

the risk of shrinkage cannot be ruled out.

Despite the number of shortcomings, this type of foundation is still used in construction, and quite often.

Another option for a strip foundation made of blocks Source proffu.ru

Slab foundation for a house

A monolithic slab is a foundation that occupies the entire area of ​​the house. This type of construction is quite expensive, because construction will require a lot of concrete and reinforcement, but the large investments are justified by the high reliability of the slab in problematic soils.

A monolithic slab is classified as a floating foundation; all loads on it are distributed evenly, which completely eliminates any deformation in soil prone to horizontal shifts or heaving soil.

Construction features: a pit of the required size is dug, the base is prepared, a reinforced belt is installed, and then it is filled with mortar. The slab is not very thick, but has a fairly good load-bearing capacity and high strength characteristics.

The process of constructing a slab foundation Source dom.e1.ru

The thickness of the monolithic slab is made from 30 to 100 cm, depending on the mass of the future house. On such a foundation it is possible to build heavy structures up to five floors, as well as houses of complex design and great length. The technology for constructing a monolithic slab as a foundation allows expansion joints to be made along its perimeter, which increases the strength and reliability of the structure.

The disadvantage here is that once the slab is laid, you cannot build a basement. However, this minus can be compensated for by the construction of a basement floor. The foundation is perfect if housing construction will take place on swampy or muddy soil, as well as on artificially formed embankments.

Ready slab foundation Source stroidom-shop.ru

Pile foundations used in residential construction are classified into three types: driven piles, screw piles and bored piles. Driven pile construction is used for the construction of heavy houses made of concrete and brick in problematic soil. Driven piles are supports with a length of 5 to 12 m; they are resistant to heavy loads, and in terms of reliability and strength they have practically no analogues.

Video description

What are the features of concrete driven piles? We'll talk about pile foundations in our video:

To build a foundation on bored piles, you will need to concrete wells drilled in the ground. In turn, bored piles are divided into handicraft and industrial elements. The latter are installed using a mobile drilling rig, and their performance characteristics are almost identical to driving ones. Home-made piles (analogues of a columnar foundation) require installation to a depth of 2 to 3 m using hand drills.

Construction of a pile foundation on heaving soil Source mastery-of-building.org

Screw piles from 3 to 8 meters long are immersed in the ground by screwing. Light wooden structures are built on such foundations - frame houses, cottages made of timber or rounded logs. Foundations on screw piles are chosen when it is necessary to build a house in a short time. It takes several days to install the piles and about three more days to tie them.

Video description

What are the pros and cons of a pile screw foundation? Is it possible to make a high-quality foundation for little money? Watch in this video:

For bored and driven piles, a slab or strip grillage made of concrete is used for strapping; the screw supports are tied with a grillage made of timber or I-beams, or a channel.

This is what a pile foundation looks like Source skalice.ru

Frame house on a pile foundation Source kursremonta.ru

Columnar foundation

The construction of a columnar foundation involves the distribution of supports at a distance of 2-3 m from each other along the entire perimeter of the future house, the pillars are tied with a grillage. Columnar foundations, like strip foundations, are divided into prefabricated and monolithic. The latter is a concreted asbestos-cement pipe. The prefabricated one is built from FBS blocks or bricks.

The columnar foundation is tied with a grillage made of an I-beam or timber. The strapping is necessary to combine the poles into a single structure, which allows you to evenly distribute the load coming from the house and prevent them from tipping over.

Columnar foundations are used for the construction of frame houses and other light buildings up to two floors in height. The bearing capacity of a columnar foundation cannot withstand heavy brick and concrete houses. In addition, this type of foundation is not suitable for construction in heaving and moving soils.

The impact of soil heaving forces on a columnar foundation Source silastroy.com

Insulation and waterproofing of the foundation

Thermal insulation and waterproofing of the foundation for the construction of private housing should be given special attention. Such work is very important, since thermal characteristics, a comfortable microclimate in the house and the durability of the building depend on them.

Waterproofing is necessary for any type of foundation, because it is constantly exposed to groundwater and melt water. Most often, roll pasted and liquid coating waterproofing is chosen for protection. The latter includes bitupen-polymer emulsion. When choosing rolled waterproofing, it is better to give preference to fiberglass, polyester or fiberglass.

Waterproofing of a monolithic foundation Source rfund.ru

For foundation insulation, the following are used: penoplex, expanded polystyrene, polyurethane foam, mineral wool, slag, expanded clay.

What determines the price of a foundation for building a house?

The foundation takes on a lot of the weight of the built house and distributes it evenly on the ground surface. The worse the bearing capacity of the soil, and the heavier the house, the more reliable and durable the foundation should be, therefore, the price of its arrangement will be higher.

For light houses, foundations of pile and column type are suitable, but for buildings that are heavy, you will need to create a more massive foundation, here the choice is given in favor of the slab type or strip type. The cost of any foundation also depends on its depth, which is done taking into account soil freezing.

If the base is more than twenty centimeters in height, then this significantly increases the cost of materials to create the base. In the middle zone of our country, the base is made in height from 45 cm to 50 cm. In addition, if the soil at the construction site is problematic, then it will be necessary to resort to additional work: arrangement of a drainage system through which groundwater will be drained and high-quality soil compaction.

Video description

What types of foundation are there? How is the foundation built and how much does it cost? See all this and much more in this issue:

Conclusion

The construction of a foundation is a very important stage of work, so its selection and arrangement should be approached thoroughly. To save your own time and effort, it is better to contact a construction company, where they will not only advise you on the most suitable type of foundation, but will also construct it with high quality.

To make the foundation correctly, you need to carefully study the options for construction types and their features. The construction of the underground part is carried out taking into account the following requirements:

• economic expediency;
• reliability;
• strength;
• durability;
• sustainability.

Before starting construction work, a soil study should be carried out. The choice of the right type of foundation is influenced by the total weight of the house, the strength of the soil and the groundwater level. A foundation that is carefully made and built in compliance with technology will last a long time and will not cause problems during operation.

Preparatory stage

It’s worth starting with pits or drilling. The main goal of this activity is to find out what soils are located on the site, as well as to find out the level of groundwater. The foundation must be laid in compliance with the rule: the mark of the sole must be at least 50 cm above the level of the water horizon.

How to do soil testing correctly? Two methods are used for this:

• excerpts of pits (deep holes, dimensions in plan are usually 1x2 m);
• manual drilling.

In the first case, the soil on the walls of the pit is examined. They also check to see if water has left the bottom. In the second option, the soil on the tool blades is examined.

Once you have determined what kind of soil is on the site, you will need to find its strength indicators. This can be done using special tables.

The cost of laying the foundation for a house can be up to 30% of the estimate for the entire building. To avoid cost overruns, you need to perform a calculation that will allow you to find the optimal design parameters that will simultaneously guarantee minimum costs, strength and reliability. For your convenience, you can use online payment.

Types of foundations

Building a foundation with your own hands involves the use of several technologies:

• ribbon;
• combined options.

Columnar supports have a low load-bearing capacity. It is possible to install monolithic pillars or assemble them into compact concrete blocks. Both options are great for DIY projects.

There are three types of pile foundation for a house:

• driven (not recommended for private buildings due to the need to attract equipment);
• (suitable for building a brick or concrete house);
• (ideal for light wooden buildings).

Piles make it possible to reduce the amount of excavation work. There is no need to dig trenches or a foundation pit or transport large amounts of soil outside the site. Thanks to this quality, installing this type of foundation is a very economical choice. The main disadvantage will be the impossibility of equipping a basement or underground for utilities. In this case, the base of the building is covered with decorative materials.

Another advantage of piles is the possibility of using them in wetlands. Even if the groundwater level is located close to the ground surface, the supports provide the necessary load-bearing capacity.

The next option is tape. It can be made monolithic or from blocks. The second option is rational to use for mass construction. Strip foundations are:

• recessed (for buildings with a basement, brick and concrete structures);
• (for wooden and frame houses);
• non-buried (technology of pouring foundations for small buildings on a solid foundation).

Before making a tape, it is worth checking the groundwater level and compliance with the rule that the sole cannot be closer than 50 cm to the groundwater horizon. Otherwise, there is a high probability of flooding of the basement, reducing the load-bearing capacity of the foundation and destruction of the materials of the supporting part of the building.

What to do with high groundwater level? If the structure is made independently from brick or stone, screw piles will not be suitable, and for bored piles it will be necessary to lower the water level. An excellent option would be filling. In this case, a non-recessed or slightly recessed base is made. The thickness of the slab is determined depending on the load, on average 300-400 mm.

How to pour a foundation for a house

Monolithic foundation type is the best option for private housing construction. In this case, laying can significantly save on transportation and installation of structures. There is no need to hire a crane to install elements in the designed position or a KamAZ truck to transport concrete blocks and slabs.

Monolithic foundations can be made from factory-made concrete or you can mix the solution yourself using a concrete mixer. The first option is recommended. The fact is that it is very difficult to strictly observe the proportions of the composition in artisanal conditions. For factory-mixed concrete, such a guarantor will be a passport, which indicates the verified indicators of the material.

To make the material yourself, you will need to prepare clean water, cement, sand and crushed stone (or gravel). They are mixed with each other strictly observing proportions, which depend on what grade of concrete needs to be obtained. If you add a little more sand or crushed stone to the composition than required, the strength of the supporting part of the building will suffer.

To properly pour the foundation, you need to familiarize yourself with the basic rules of concreting:

• Concrete must be poured in one go at time intervals of up to 1.5 hours. If you take long breaks in work, the solution sets and concreting joints form, which weaken the structure. The technology allows making horizontal seams if absolutely necessary. It is unacceptable to install vertical seams on a monolithic foundation, since in this case the support of the house will not be able to resist soil deformations.
• The class of concrete is selected depending on the type of supporting part. For a columnar or pile foundation, class B 15 is sufficient. For tape, grades from B 15 to B 22.5 are needed. Construction of a house foundation using slab technology requires concrete grades B 22.5 or B 25.
• After pouring, the material should gain strength. On average, this takes 28 days. Construction work can continue after the structure reaches 70% of its original strength.
• It is better to carry out work in warm, dry weather. The ideal average daily temperature for concrete hardening is +25°C. At temperatures below +5°C the material practically does not harden. For normal hardening in this case, special additives and heating are used.
• The concrete must be maintained within 1-2 weeks after pouring. It involves wetting the surface with water.
• To mix the mixture yourself, you will need cement, sand, crushed stone (gravel) and clean water. The proportions depend on the strength class. The material is delivered from the factory using a concrete mixer truck - it allows you to extend the life of the solution and deliver it over relatively long distances.

How to pour the foundation correctly? In general, work is performed in this order:

1. installation of formwork and reinforcement cage;
2. laying waterproofing material in formwork;
3. pouring concrete;
4. its compaction by vibration or bayonet;
5. curing;
6. stripping works (if necessary).

To quickly complete the work, it is recommended to order a concrete pump together with a concrete mixer. Concrete manufacturers are usually willing to provide this technique. In this case, it is necessary to use a concrete mixture of grades P3 or P4 in terms of mobility. Otherwise, the equipment breaks down.

Step-by-step instructions for pouring a strip foundation

Concreting is considered using the example of a monolithic tape. To erect the supporting part of the structure, construction is necessary. To do this, use cast-offs and construction cord. You need to show the edges of the tape.

After marking, the soil is excavated. If there is no basement, it is enough to dig a trench. At its bottom you need to make a sand cushion. It performs several functions:

• ground leveling;
• prevention of frost heaving;

Next stage - . For this purpose, the material included in the estimate is used: boards (removable type) or polystyrene foam (non-removable). The second option serves not only as a form for pouring concrete, but also as insulation of the underground part of the building. When installing the formwork, I raise the base to the desired height.