What foundation to place a two-story house on. What is the best foundation to pour under a brick house? Types of pile-grillage foundations

To ensure that your house lasts for a long time, you need to choose and make a good one. For a house made of bricks, a reinforced foundation is needed. At the base of a house made of foam blocks, you can make a simpler foundation. The construction market does not stand still and now there are many materials that allow even beginners in construction to make an excellent foundation for a brick house with their own hands.

Thanks to the development of modern technology, there are many types of bases. They differ in design features and characteristics.

There are criteria according to which the foundation option is selected: the size and weight of the house, features, topography on the site, the presence of groundwater, whether the soil freezes.

A special feature of a room made of brick or stone is its high mass. Average brick house one floor, can be much heavier than a two-story wooden house. The density of bricks intended for construction is 1.5 tons per 1 kb/m. The density of pine or spruce is 500-600 kg.

ATTENTION: according to construction standards, it is not recommended to lay a shallow strip or pipe foundation. These options have low load-bearing capacity and the pipes are susceptible to corrosion.

The area of ​​the building is also important. If you are going to build a house on two floors, then the foundation will have to be made stronger. When pouring the base, it is best to comply with all SNiP standards. Prepare a layout with all the calculations necessary for construction.

Soil characteristics

Soils are:

• Weak ones (clay, soils with swamps) - collect moisture, are not strong and therefore cannot support houses in a large mass, especially if you plan to build several floors; in winter the soils become heaving. The collected moisture freezes and becomes ice, increasing in volume. As it expands, bumps appear and the base becomes deformed. Houses on stilts are suitable for such soils.

IMPORTANT: If you decide to install piles, then make sure that they lie deeper than the ground freezes.

• Medium soils are loamy soils. It is important to know at what depth the groundwater lies.
• Durable - rocks or sandstone. They can withstand any foundation: from shallow foundations to strip foundations. These rocks do not collect moisture, so they are not affected by frost.

Features of groundwater occurrence

This is an important indicator when laying the foundation. The higher the groundwater is, the greater the likelihood that heaving will occur. You can’t build on such soils. The best option would be a monolithic “floating” slab or piles. The disadvantage of such foundations is that it is impossible to build a large building.

When building a two-story house, you will need to greatly strengthen the foundation. You can also build drainage and make a strip base. Remember that the foundation should be located below the level from which freezing occurs. For example, this is an ideal option for the south of Russia, the freezing level there is no more than 0.5-0.7 m. In the north, the freezing depth is more than 1.5 m, so in terms of price it is very expensive.

IMPORTANT: when laying a foundation from strips, when the water is high, you can organize good waterproofing. If it is not provided for, then water will leak through the cracks and cracks into the basement, causing mold and mildew to multiply. Moisture in winter will expand and destroy the foundation.

Brick as a material

A brick house has two features: they have a large shrinkage and a large mass.

The problem of shrinkage is common to all houses built from small materials. It compresses well, but when stretched or bent, it easily breaks.

The worst thing is uneven shrinkage, which causes:

Due to the occurrence of these problems, strength and reliability are significantly reduced. You should also remember about deformations that will lead to distortions:

1. Large shrinkage of various parts. Most often this happens due to a violation of the technological process or poor study of geology. Shrinkage occurs in areas of weak soil or poor compaction.
2. Buckling is the reverse process, when not shrinkage occurs, but individual parts begin to rise. This is possible due to the appearance of groundwater and the shallow depth of the foundation.

In these cases, it is necessary to strengthen the supports and strengthen the soil. Of course, you will have to spend a good amount of money, so choose the right foundation option, as well as follow the technological process.

Brick is one of the problematic materials. Only the reinforced concrete structure is more massive. Considering these features, we can say that many foundations simply cannot cope with such a load.

Foundation options

If you want the foundation to last for many years, you need to choose the most profitable option. The type of foundation will directly depend on the weight of the future building. The most profitable are pile, slab and strip foundations.

Let's consider options for laying foundations.

1. A pit, especially if the plans include a zero level or a house with a basement.
2. Preparation of a trench if the house will have 1-2 floors and a basement is not provided.

With any option, several requirements must be met:

• - peculiarities ,
• - soil freezing,
• - how does groundwater flow?
• - relief features.

IMPORTANT: To ensure that the preparation work is completed efficiently, it is best to contact a specialist.

If you can’t turn to specialists, follow several standards:

You also need to consider the type of house that will be built:

• — It is best to build simple houses on monolithic and solid foundations.
• — Houses are built on stilts when the soil is weak or if the plan is for a large building.
• — If you want to build a house with a basement, ground floor, large in size, choose a strip foundation.

NOTE: there are several rules for the depth of laying the foundation of a brick house. The depth depends on the heaving of the soil, freezing characteristics, as well as the presence of groundwater.

Strip foundation for a house

This is the most popular option. It can withstand massive structures and is also easy to manufacture. Such a foundation is placed along the entire perimeter of the future house, as well as under load-bearing walls. With this option, you can plan a basement or basement.

The foundation can be monolithic or prefabricated. The first option is a reinforced structure, completely filled with concrete. Very solid foundation, which you can do yourself. The biggest disadvantage is the long time required for complete hardening.

Prefabricated - it is made from blocks (stone or concrete). It can be built quickly, but you will need special equipment and assistants. This option will not be as durable as a monolithic one.

Based on the load exerted on the ground, they are divided into: shallow and buried. The first ones are laid to a depth of 0.5-0.7 m. Small simple buildings can be erected on them. Houses made of bricks, as we already know, are very heavy and it is difficult to support their weight, because of this it is best to make a recessed version. It is made below ground freezing by 0.3 m, especially if there is a basement and basement.

The price of the foundation of a brick house also depends on the distance to the site from the city, where you can purchase all the necessary materials. So:

IMPORTANT: Place roofing felt along the bottom to make high-quality insulation.

• Make a belt out of . It is best to take rods 6-10 mm. Connect the rods together using welding machine. The resulting frame is lowered into a trench and laid on brick or stone supports.
• Pour the concrete in several batches. Each layer should be approximately 15-20 cm. Using a vibrating hammer, if you don’t have one, then shake each layer with a shovel. Thanks to this procedure, there will be no voids left.

IMPORTANT: the concrete solution must be of medium fat content. In this case, it does not flow on its own; you need to try to distribute it.

• Leave everything until it dries. The average drying time is up to 30 days. Don't forget to soak the frame with water to prevent drying out.
• When the concrete has hardened, remove the formwork. Insulate from water. For these purposes, various materials can be used.
• Fill the foundation, but do not disturb the waterproofing.

Pile foundation for a brick house

When the soil cannot support a large and heavy house, then it is worth considering the option of laying a foundation from piles. In this option, most of the load is transferred to the ground, located much lower. The piles are connected to each other with a solution of concrete or reinforced concrete, on top of which the walls will already be erected.

A pile foundation can be made on any soil, this will reduce your materials and work. The main disadvantage when constructing such a foundation is the need for special equipment that can drill a well or drive it.

There are different options for foundations of this type. The best option is a bored version with reinforced concrete piles. You can make such a base either with your own hands or using special equipment. The cost will also depend on the distance of the construction site from the city.

If you prefer this option, you will need:

• We clear the area and remove the top layer. Make the corners strictly straight.
• We mark the places where they will be. We make a small recess under each pile.
• We make wells in which the piles will be located.
• To make a frame, weld reinforcement rods together. The frame should be 0.2-0.3 m above the ground.

IMPORTANT: when the piles extend above the ground, the formwork can be constructed from metal pipes.

• We fill the bottom with sand and gravel. We arrange the frame from reinforcement and concrete it. Don't forget to get everything sorted out. Concrete can be purchased or made independently directly at the construction site.
• We make a frame for the grillage and connect it to the piles. We install the formwork.

IMPORTANT: the formwork for the grillage can be made prefabricated. It is easy to install, and the grillage will be more durable.

• Pour the concrete solution. Don't forget to get everything sorted out.
• We leave everything to dry and waterproof it.

Everything is ready and you can build the walls of your future home.

Slab foundation

The simplest option. This is located throughout the entire area. This foundation perfectly distributes loads and is well suited for heaving, subsidence soils.

Consider the installation of a shallow tiled base. You will need reinforced concrete beams, reinforcement, and slabs that will need to be connected. Let's get started:

1. We clear the area. Remove the top layer of soil. We make markings.
2. We go deeper a little lower than the thickness of the foundation.
3. Level and sprinkle with sand and gravel. We go through the vibrating plate. Pour a thin layer of concrete mortar.
4. We lay vinyl film, roofing felt or geotextile over the entire surface.
5. We make formwork around the perimeter.
6. Place a mesh of reinforcement inside the formwork.
7. Pour the concrete solution one time. This will help avoid cold bridges. Work it out with a vibrator.
8. The pillow takes 2-3 weeks to dry.

How to strengthen the foundation of a brick house

Sometimes, when the foundation is ready, you have to change the material for building walls. If the foundation is not strengthened, cracks and distortions may occur. The most the easy way, is to increase the base, but there are other possibilities.

• — Injection – we dig up soil around the perimeter of the base and spray concrete mortar onto the walls. This can be done with a special gun.
• — Reinforcement with piles. They are installed immediately at the foundation.
• — We make formwork around the circumference, lower the finished reinforcing frame and pour concrete.
• — Another concrete wall.
• — Expansion of the pillow by increasing the walls by 0.5 - 1 m.

You have decided to build a brick house, think about what the foundation will be like. From the article you understood that a brick house is very massive, so to avoid problems, choose the right option.

This article is an answer to a question from one of our company’s clients that recently came to the email of the Bogatyr company.

Nikolay, 29 years old, Moscow! “Hello! Your company was recommended to me by my brother, for whom last year you laid out a pile foundation for a shopping center in Moscow. He spoke extremely positively about the company’s specialists, and I also decided to use your services. I have a spacious plot of land in the Moscow region, on which I I plan to build a one-story brick house with an area of ​​90-100 square meters. Now I’m thinking about what kind of foundation is best to use. The soils on the site are heaving, as the neighbors say. I can’t say for sure about the depth of groundwater, I haven’t carried out geodesy of the site yet. I’m interested in the following - "On what foundation is it most rational to build a brick house, taking into account an unlimited financial budget? The main condition is durability and reliability, I want the house to be built “to last forever,” as they say. Thanks in advance for your answer."

Since this information will be of interest to a wide range of readers, we decided to consider it in detail in a full-fledged article.

From the material you will learn what should be considered when choosing a foundation for a brick house, and how the main types of foundations used in private low-rise construction are built.

Choosing the type of foundation for a brick house

Brick houses, even if they are built on 1-2 floors, belong to the category of heavy buildings. Only a few types of foundations can be used as a foundation for such buildings, namely:

• Tape;
• Slab;
• Pile.

The most cost-effective type of foundation is a shallow strip foundation - however, its use is only possible in non-heaving soils, which are extremely scarce in the Moscow region.

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The most reliable foundation with high load-bearing characteristics is a foundation made of a monolithic slab, which is also the most expensive due to the large number of materials required for construction.

Pile foundations are the “golden mean”; with the correct configuration, foundations on driven piles They are not inferior, and in certain types of soil they exceed the load-bearing properties of slab foundations; work on their arrangement is completed faster and they cost less.

Rice. 1.2

Important: the economic component is only a minor criterion when choosing a foundation for a brick house. First of all, it is necessary to be guided by the standards for the compliance of foundations with a specific type of soil and the weight and size characteristics of the building being constructed.

The main factors that determine the type of foundation on which a brick house should be built are the following:

• Type of soil at the construction site;
• Soil freezing depth;
• Groundwater level;
• Weight and number of storeys of the building.

To obtain information about the characteristics of the soil, it makes sense to use the service of a geodetic survey of the site, since without special equipment it is impossible to collect all the necessary data, and it is they that have the maximum weight when designing any foundation.

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Let's consider the relationship between the type of soil and the type of foundation for a brick house:

• Strip foundations - are erected on dry cohesive soils and sandy soil, they are subject to the effects of heaving forces, therefore, when laid in heaving soil, they must sink below the depth of its freezing;
• Slab foundations - suitable for problematic soils prone to shifts and subsidence soils, have high resistance to soil heaving;
• Pile foundations are a universal option for all types of soil with the exception of rocky soil.

Based on the weight and size characteristics of the building being constructed, the choice of foundation is as follows:

• Tape - suitable for 1-2 storey brick houses, they allow you to equip the ground floor or basement;
• Slab - used for the construction of 1-3 storey houses from timber, bricks and logs. Houses of a standard rectangular shape are built on such foundations, since pouring monolithic slab complex configuration is problematic. If it is necessary to equip the basement floor, the foundation slab is installed at the bottom of the pit;
• Pile foundations - with appropriate design pile foundation any houses can be built on it, including multi-storey buildings. Such a foundation does not provide for the possibility of arranging a basement.

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Strip and slab foundations are subject to the effects of frost heaving of soil and groundwater, depending on which the required foundation depth is determined:

Strip foundation for a brick house

When building a one-story brick house on a site with normal soil conditions, the best option is a strip foundation. The construction of a foundation strip that follows the contours of the house requires an order of magnitude less materials than the formation of a monolithic slab.

The width of the tape is determined based on the thickness of the walls; it can be 10-15 centimeters thicker and form a protruding base, or be laid at the same level as the wall.

The depth of laying the foundation depends on the degree of heaving of the soil. On non-heaving soil, it is permissible to build shallow foundations, lowered into the soil by 50-70 centimeters.

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The sequence of work on arranging strip foundations is as follows:

• On the site, the contours of the foundation are marked along the external and internal walls of the house;
• A trench is excavated to a depth of 20-30 centimeters greater than the design depth of the tape;
• A sand and gravel cushion is formed at the bottom of the trench, which acts as a compacting layer that prevents soil shrinkage;
• On the sides of the trench, to the height of the elevation of the foundation strip above the ground, a formwork is formed from boards, which is strengthened with lateral supports and covered with waterproofing material;
• A reinforcement frame is knitted from reinforcing bars, which has two contours - the central part of the tape does not require reinforcement, since all loads are distributed in its upper and lower parts;
• The frame is placed in a trench and the foundation is poured with heavy concrete of class A300.

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Pile foundation for a brick house

A foundation made of driven reinforced concrete piles is a universal type of foundation that is applicable for the construction of houses of any number of floors on all types of soils common in the Moscow region.

You cannot make such a foundation yourself, since the immersion of pile pillars is carried out by special construction equipment, but by ordering it from our company you can be sure that the foundation of the house will withstand any load and will last for decades.

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Work on arranging a pile foundation is carried out in the following sequence:

• The foundation is designed, the layout of the piles under the walls of the house is determined - under standard conditions, the pillars are placed along the perimeter of the external and internal walls in increments of 2-2.5 meters, as well as at the places where they intersect;
• Piles are delivered to the site, construction equipment is relocated;
• The territory of the site is leveled, the top turf layer of soil is removed and the places for driving piles are marked;
• The pile driver drives piles using the impact or vibration method;
• The piles are tied with a grillage - it acts as a support on the surface of which the walls of the house are laid.

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The construction company "Bogatyr" guarantees high-quality performance of the entire range of piling works when constructing foundations from driven reinforced concrete piles. We are ready to design a foundation for any building, supply high-quality piles and drive them into any type of soil. Thanks to the use of modern piling equipment, all work is completed in the shortest possible time.

Slab foundation for a brick house

If you prefer to build a foundation with your own hands, but are dealing with problematic soils that have uneven density and are prone to shifts or frost heaving, pay attention to a foundation made of a monolithic concrete slab.

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The slab can be laid either with a small recess equal to its thickness (which, in most cases, does not exceed 50 centimeters), or placed at the bottom of the pit, which allows you to create a full-fledged basement floor.

The construction of a slab foundation is carried out using the following technology:

• The contour of the slab is marked on the site and excavation work begins to dig a pit. If the slab is deeply buried, excavators are used for this; if it is located on a surface, it is quite possible to do it with manual force;
• A layer of footing 2-3 centimeters thick is poured from liquid concrete, which will serve as the basis for pouring the main slab;
• Wooden formwork is installed on the sides of the pit;
• A reinforced frame is created over the entire area of ​​the slab. The number of contours is 2; corrugated reinforcement rods with a diameter of 12 mm or more are used as horizontal frame elements, which are connected by vertical jumpers. The frame is fastened with knitting wire or welding;
• The reinforced frame is laid on the concrete base and the slab is poured. For this, a batch of ready-made concrete is used, ordered in the required volume, since the pouring must be completed simultaneously.

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Drainage system for a brick house

When the groundwater level is high, to protect strip and slab foundations from erosion, it is necessary to provide a wall drainage system. It is necessary to equip it at the stage of laying the foundation, so as not to carry out excavation work to excavate it again in the future.

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Drainage pipes are located around the perimeter of the house, encircling the contours of the foundation. They are placed 10-20 centimeters below the supporting heel of the base. In the corners of the house, pipes are brought into inspection wells, which are connected to the main storage tank located at the lowest point of the site so that water from the inspection wells flows into the container by gravity. Water is pumped from the main reservoir outside the site.

Foundation insulation

Base insulation is one of the most effective ways protect the foundation of the house from the negative effects of the soil environment in which it is located. Most often, insulation is used when arranging the basement floor.

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For thermal insulation of the foundation High-density board insulation is used. Such products are presented in the assortment of all leading companies engaged in the production of thermal insulation materials. The best insulation products made from extruded polystyrene foam from the companies Penoplex and TechnoNIKOL have proven themselves.

Insulation materials are glued to the foundation walls using bitumen mastic, after which the surface of the thermal insulation is puttied and covered with a layer of protective geotextile.
Gain

To strengthen the foundation they do not resort to it at the stage of its construction, but if the foundation is not designed correctly and is not able to withstand the weight of the building or the load of heaving forces exerted on it, such a measure may be needed quite soon.

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In construction practice, the following methods of strengthening foundations are used:

• Arrangement of reinforced concrete frames and jackets, which represent an additional layer of concrete that increases the foundation strip - a sheet metal shell is installed around the perimeter of the base, which is fixed in the base walls using reinforcement, after which the cavity between the metal and the foundation is filled with concrete;
• Widening the area of ​​foundation support - for this, reinforced concrete slabs or blocks are used, placed under the supporting heel of the foundation strip;
• Strengthening pile foundations is done by driving additional piles next to existing pillars.

Our services

We are a construction company and the main activity of our company is driving piles in Moscow and the region. We use our own equipment with high productivity, so we do not delay the delivery of the pile foundation. To order work on driving piles, leader drilling, driving sheet piles or for supplying reinforced concrete piles to the site, use the application form:

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The foundation for a two-story house is a fundamental element characterized by a high degree of reliability. The strength of the entire building will depend no less on how skillfully the installation work is carried out. The algorithm of actions at each individual stage of constructing the foundation of a house involves taking into account all kinds of requirements and conditions, both recommendatory and mandatory.

Strict adherence to the presented instructions will help not only to avoid negative consequences during the construction of a two-story residential building, but will also strengthen the guarantee of its safety.

Types of foundation

According to the method of execution, it is divided into several types. The most common ones are:

• columnar;
• pile;
• tape;
• monolithic slab.

Private residential building

Columnar

The use of the presented type is more justified in the construction of panel townhouses, and, for example, houses made of aerated concrete or a Finnish mansion made of timber boards resting on pillars have gained popularity not only in our country, but also abroad.

The technology for constructing such a foundation boils down to installing supports along the intended perimeter of the future building. They are installed at certain intervals in pre-drilled holes. The diameter of the latter is variable.

These indicators are determined by calculating the degree of load per unit area.

Taking into account what depth is most appropriate in a particular case, builders give preference to different types of pillars. Pipes, reinforced concrete stepsons, logs, and natural stone can act as supports.

Pile

Another type of supporting element that has become widespread in various fields of construction is the pile. Modern technology for using piles as a key component of the supporting surface is a single complex of complementary structural elements.

This engineering solution eliminates deformation of individual peripheral parts and ensures uniform distribution of force on the ground.

According to the principle of pile installation, the pile foundation is divided into hanging and retaining.

Scheme of the pile-tape design option

The first category of load-bearing supports is installed in dense soil layers, the height of which reaches several meters. Piles are driven into the ground at calculated intervals. A significant part of the load of such a support falls on its side surface, while the base plays a secondary role.

In this position, the soil under the pressure of the support walls can, as they say, “crawl.” This disadvantage is compensated for in the following ways:

• increasing the cross-section of workpieces;
• increasing the length of the pile;
• giving the shape of the pile convexities at the base and in places of lateral contact with the ground;
• increasing the density of pile installation.

Screw pile installation diagram

Retaining piles are very different in functionality from previous models. Unlike pile and hanging supports, this type of base structure is driven to a shallow depth with a small interval between two adjacent elements. The average height of such supports is 40–70 cm. This technology is typical for 1-story frame-type buildings.

Tape

The so-called strip type of laying the foundation of a building deserves special attention. Its fundamental difference is that in the presented case they use a block type of backfill or a continuous concrete strip.

In accordance with the requirements for strength and load, the blocks can have a solid or hollow structure. Houses made of aerated concrete based on this technology are characterized by high seismic resistance and durability.

Depth drawing

Monolithic slab

Slab foundation - it is characterized by a large load-bearing area and an exceptionally high level of resistance to seismic ground vibrations.

Read also: Caring for the foundation after pouring: spring, summer, autumn and winter

In the event of natural disasters causing displacement or subsidence of the soil, such a structure will remain intact and unharmed due to the large base area monolithic foundation, made in the form of a single plate.

The height of such a platform varies according to the conditions of a particular area. However, the implementation of such a project will require significant material investments. On average, it takes about 20–25 m3 of concrete to make a slab alone, but it all depends on the size and loads of the building.

Reinforcement of a monolithic slab

The best choice for a two-story house

Choosing the most optimal foundation installation technology is the key to trouble-free, long-lasting construction. At this stage, it is extremely important to conduct a comprehensive analysis of the features of a particular object. In this case, it is necessary to take into account the maximum permissible loads on the supporting structure.

To resolve the dilemma of which foundation is better, you should turn to statistical data. The widespread practice of using various types of foundations for a two-story brick house allows us to confidently state that strip technology in this case acts as the highest priority direction.

For example, the foundation for a two-story house made of foam blocks based on this technology has already gained popularity among many happy owners. The prerequisites for choosing the presented method are based on the optimal combination of various technical, material and operational criteria.

The advantages of this method are as follows:

• high level of load-bearing capacity;
• high performance indicators;
• resistance to deformation and tearing;
• ease of installation;
• low level of material costs;
• ease of maintenance;
• the ability to choose different types of layouts;
• minimum technical equipment.

Installation of formwork

It should be noted that all the positive aspects of the recommended technique will manifest themselves only if they strictly comply with the requirements and the availability of good-quality materials.

Foundation calculation

This procedure, as a rule, does not cause serious complications if you approach it with the proper level of responsibility. It involves collecting load data and studying the load-bearing layers of the soil. The thickness of the foundation for a two-story house will be determined depending on the ratio of these two components.

The video explains in detail how to calculate the foundation yourself.

First of all, it is necessary to conduct a thorough study of the work site. The depth of the foundation for a two-story house made of foam blocks should be 35–55 cm higher than the average freezing depth.

Formwork and reinforcement

Such data are acceptable only if the living space is heated in the winter. Otherwise, it is necessary to adhere to the established freezing temperature for a specific region.

The relative value of the tape width will be 25 cm. This value is approximate and will change during the calculation process.

The next step is to calculate the pressure on the strip foundation for a two-story house. To determine the appropriate value, it is advisable to use the table below.

Construction type	Density (kg/m2)
Walls
Brickwork (half brick)	210–240
Houses made of foam concrete	170–180
Houses made of logs (d=240 mm)	130–145
Houses made of timber (150 mm)	11–125
Floor elements
Attic (wooden beams)	10–120
Hollow concrete slabs	30–380
Reinforced concrete floors	450–520
Roof
Metal tiles, corrugated sheets	25–35
Two-layer roofing felt	35–45
Slate (crest height – 4 cm)	50
Snow load for the central regions of Russia	100–120

The next stage is calculating the total weight of the strip slab. To do this, you must first calculate its volume, which is calculated using the product of length - L, width - A and height - B.

We multiply the resulting value by the specific gravity of reinforced concrete, which is 2500 kg/m3. The final result is the total weight. To calculate the total load - M - on the load-bearing soil layer, it is enough to add this value to the weight of the building.

Read also: Finishing the foundation of a house with panels: siding, stone and other materials

Now it becomes necessary to set the optimal value for the width of the base sole - O. It is derived using the following formula: O = 1.3*M/(L*R). The value of 1.3 acts as an indicator of the bearing capacity reserve, and R is the density of the soil layer, which is indicated in the table below.

If the width of the tape is less than the approximate value, the final width will be the declared 20 cm. If, according to the calculation results, this value exceeds the original figure by more than 4–6 cm, it is necessary to recalculate the mass of the base with a new value of the tape width.

Calculations should be made until the increase in the width of the tape is less than 5 cm.

Installation of strip foundation

The sequence of actions in the case under consideration involves the following work:

• digging a trench;
• pillow placement;
• installation of block elements and pouring of concrete strip.

Tape for building

Before you start digging a trench, you need to mark out the area of ​​the future structure and draw lines with all axes broken down. The depth of a strip monolithic foundation for a two-story house is calculated taking into account the payload of the entire building and in accordance with the results of geodetic surveys of the area.

The width of the strip reinforced foundation for a two-story house is established based on the results of the calculation data presented above.

The cushion is most often sand, gravel or concrete. The choice of material should be determined by the quality of the soil and the degree of load on the foundation. Sand is usually laid in one layer 150–200 mm thick. This pillow should be thoroughly moistened with water and compacted.

The photo shows a building strip.

Before waterproofing

It is advisable to use a mixture of sand and gravel in the presence of soil with a high content of loose rocks. This mixture is prepared from equal shares of both ingredients.

After applying the pillow, it should also be moistened and compacted. Concrete blocks are used as a base layer in extremely unfavorable soil conditions.

Such a foundation made of blocks will eliminate the possibility of subsidence and will significantly facilitate the installation of load-bearing elements.

Installing blocks for a 2-story house does not require any special professional skills. Houses made of aerated concrete, as well as foam block and aerated concrete buildings, are built using a similar principle. The blocks are installed according to markings one to one with the ends pre-coated in the solution.

Section and section

The tape is poured in several stages. First, reinforcement is laid on a cushion poured with a thin layer of concrete. It should not come into contact with the surface of the trench and formwork.

After this, the cavities of the reinforced structure are poured with a concrete solution of medium viscosity until the bottom layer is completely filled. And finally, the final stage involves filling the base part and setting the zero mark.

Once the above work has been completed, it is essential to ensure the correct level of insulation. Houses made of timber and foam concrete need it more.

Formwork and reinforcement

Installation of formwork is carried out using wooden shields, boards or flat sheets of slate.

Membrane in formwork

This event involves a strict sequence of the following operations:

1. Before proceeding with the installation of individual sections of the formwork, it is necessary to mark the area to visually determine the contours of the above-ground part of the base structure. As a rule, posts/pins are installed in the corners through which the thread is passed. For such pins, cut reinforcement is ideal. Thus, the thread will serve as a guide for installing the formwork, determining the dimensions of the foundation and indicating the base of the base.
2. For ease of installation, boards or other working material are best mounted in the form of prefabricated panels. The boards are plumb and attached to wooden supports using screws or nails.
3. Before the shields take their place, it is necessary to take care of the openings for various communications and vents. To do this, appropriate slots are first made in the panel elements of the formwork.
4. To give the structure greater rigidity, the shields should be strengthened with transverse bars. The frequency of use of such reinforcing elements is determined individually for each individual type of formwork.
5. An integral part of the strip structure is the reinforcement. Its purpose is difficult to overestimate, because it is it that creates a strong frame for the entire load-bearing part as a whole.

Ground floor basement

To reinforce the strip base, rods with a diameter of 12 to 16 mm are used. For tying reinforcement, soft steel wire is used. Unlike a welded contact, such a connection gives the entire structure flexibility and ductility.

The foundation is the main thing structural element any building. A brick house is no exception. Without a reliable load-bearing foundation, it is impossible to build a durable and comfortable home. An incorrectly laid foundation of a building can cause many troubles, including the destruction of the entire structure. Therefore, it is so important to choose the right and high-quality foundation for a brick house. This article is intended to answer the questions of which foundation is better and how it is poured.

Aspects of choice

In the arsenal of modern builders there are several types of foundations, differing from each other in their design, technical characteristics and scope. Due to these features, you need the right approach to choosing a foundation for a brick house. There are a number of criteria that have a direct impact on the operation of load-bearing foundations. The most important among them are:

• Dimensions and weight of the building.
• Physical characteristics of the soil at the construction site.
• Relief of the site.
• Groundwater level.
• Depth of soil freezing in winter.

You should take a closer look at each of these aspects to better understand what the foundation for a house should be.

Dimensions and weight of the building

A distinctive feature of a structure made of brick or stone is its heavy weight. One floor of a brick building can be larger in mass than two floors of a timber house. The thing is that the density of building bricks is up to 1.5 tons per 1 cubic meter. For pine or spruce, the density indicator is only 500 - 600 kg. This puts forward special requirements for the strength and reliability of load-bearing foundations for brick buildings.

Big brick house

According to building regulations, the foundation for a brick house should not be a shallow strip foundation. A columnar foundation made of metal pipes will not work either. This is due to the low load-bearing properties of shallow-buried strip foundations and the susceptibility of metal pipes to corrosion.

The size of the house also plays a role. Thus, the foundation for a two-story house must be much stronger than for a one-story building. And if we take into account that sometimes the height of private buildings is not limited to two floors, then the foundation must be poured in full compliance with SNiP standards. To properly equip the load-bearing foundation for a two-story brick building, you need a construction project with all the accompanying engineering calculations.

Soil characteristics

The type of soil also largely determines which foundation for a brick house should be chosen in each specific case. According to their load-bearing characteristics, soils can be weak, medium and strong. Weak soils include swampy and clayey soils, primarily due to their ability to accumulate moisture. In warm weather, such soils do not have sufficient strength to support a massive foundation structure, especially a foundation for a two-story house made of brick or stone.

In winter, swampy or clay soils susceptible to seasonal heaving. The water accumulated in their thickness freezes and turns into ice, as a result of which it significantly increases in volume. As it expands, the soil saturated with moisture begins to bulge in mounds, deforming and breaking improperly laid foundations, so on weak soils the most preferable option is a pile foundation for a house.

Piles must be driven below the freezing depth of the soil.

Durable soils include rocks and sandstones. They are strong enough to withstand any kind of foundation base– from lightweight shallow foundation to powerful strip foundation for a two-story house.

Sand and rocks practically do not retain moisture, so they are little susceptible to the forces of frost heaving. Sandy loam and loam are intermediate types of soil, the strength of which depends on the degree of their saturation with moisture, therefore, when choosing a brick foundation for a house on loamy or sandy loam soil, you should pay attention to such a parameter as the height of groundwater.

No. Type of foundation Type of soil 1 Belt prefabricated or monolithic Non-heaving soils - sandstones or rocks 2 Slab Strong non-heaving and heaving, prone to subsidence 3 Pile Any type of soil 4 Belt rubble Non-heaving and non-subsidence sandy loam and loamy

Groundwater height

The depth of the base of the load-bearing foundation depends on this soil indicator. A high groundwater level means that the soil on the site is most likely susceptible to frost heaving, so it is not recommended to build a strip foundation for a brick house in such a place. The best way out in this case, build a pile foundation or a monolithic “floating” slab. True, such options are most often used for small, lightweight buildings.

For a two-story brick house, the pile or slab foundation will have to be significantly strengthened due to the large massiveness of the building. Another option is to equip an effective drainage system on the site and lay a foundation strip.

The depth of the strip foundation in this case should be below the soil freezing level so that heaving forces do not destroy it. This option is perfect for the southern regions, where the soil freezing rate does not exceed 0.5 - 0.7 m. In the northern regions, where freezing depths can reach 1.5 meters or more, the installation of a deep foundation tape may become economically unprofitable , as it will significantly increase the total estimated cost of construction.

Also, when constructing a strip foundation with a high level of groundwater, one should take into account the costs of high-quality multi-layer waterproofing of the walls and floors of the basement. Without this, ground moisture will penetrate into the basement through the slightest cracks and pores in the concrete walls, which will cause the development of fungus and mold. Water that gets into the pores of concrete will expand them when they freeze, forming cracks.

Many private developers have a question: “What should be the depth of the foundation for a two-story house?” The strength of the entire building depends on this, and if we take into account its considerable dimensions and weight, then the construction of such a load-bearing foundation should be approached very responsibly, taking into account all the nuances. The table shows the recommended foundation depth for a two-story brick house on soils with different groundwater levels.

Soil susceptibility to heaving Depth of water Required depth of the base of the base Non-heaving Not regulated At least 0.5 m, regardless of the level of soil freezing Heaving Above the soil freezing level Below the soil freezing level Heaving 0...2 m below the freezing level At ½ of the soil freezing depth, but not less than 50 cm Heaving More than 2 m below the freezing level At ¾ of the soil freezing depth, but not less than 70 cm

Types of foundations

After familiarizing yourself with the main criteria for choosing load-bearing foundations, you should consider in more detail technical features one or another foundation for a brick house. Three types of bases are most often used in this capacity:

To understand how to make the right foundation, you should familiarize yourself with the technological nuances of its construction.

Tape base

A strip foundation for a brick house is the most common type. Among the advantages of this option are its simplicity and ability to withstand very heavy loads, which is especially important for massive buildings, for example, for a two-story brick house. Depending on the design features, tape bases are divided into two types:

Monolithic bases are cast directly at the construction site from concrete mortar. Before concreting begins, formwork is constructed and a reinforcing frame is assembled in it. Prefabricated strip structures are assembled from blocks using lifting equipment. Structurally, the foundation strip is a concrete strip running under all the supporting walls of the building, both external and internal.

The width of the strip foundation can vary from 30 to 60 cm: this is exactly the size of monolithic foundation slabs regulated by construction GOSTs. If the width of a strip foundation for relatively small and light brick buildings can be 300 mm, then the thickness of the foundation for a two-story house should be at least 400 mm.

In addition, the strip foundation of a two-story brick house must be buried at least 50 - 70 cm, provided that it is built on strong, non-heaving soils. Shallow foundation options are absolutely unacceptable in this case, as they have insufficient strength.

Pile foundations

This type of foundation is usually used when constructing a building on weak, swampy or heaving soils. A feature of construction on such soils is the need for a solid foundation that can ensure the stability of the building. For these purposes, the base of the foundation must be buried down to solid rocks to prevent shrinkage of the building. Or the bottom of the base should be below the soil freezing level during the cold season. This will prevent it from being squeezed out of the ground by frost heaving forces.

Pile foundation for a brick house

In this case, the most optimal technology is the method of driving or screwing piles into the ground. This allows you to save a lot of effort, time and money that would be needed to carry out excavation work and pour a monolithic tape of the same depth. There are three technologies for constructing a pile foundation:

The driving method consists of driving the pile into the ground using a special pile driver. It can be mechanical, suspended from a crane or excavator. In private construction, a manual piledriver driven by the muscular power of people can also be used. Bored technology involves drilling a hole of the required depth in the ground, after which it is reinforced and filled with monolithic concrete.

When pouring piles yourself, you should strictly follow construction technology - use high-grade concrete (from M-400) and vibrate the poured solution. If these rules are not followed, the support piles may turn out to be too weak, having air cavities and cavities inside them.

With the screw method, special piles with a spiral tip are used to construct a load-bearing foundation. They are driven deep with mechanical or manual pile drivers, and the whole process resembles tightening a self-tapping screw or a corkscrew.

Slab foundation

A relatively rarely used technology in residential construction. Classical slab foundation It is a reinforced monolithic slab cast on a sand and gravel bed. The low prevalence of this option is associated with a number of operational disadvantages. Firstly, the slab base excludes the construction of a basement, plinth or underground under the house. Secondly, such a foundation is used only in the construction of buildings that are small in weight and size.

The slab foundation of a two-story brick house can be too expensive for the developer due to the large volume of concrete poured.

Therefore, the base slab in private brick construction is used only in cases of extreme necessity. For example, if construction is carried out on unstable soils. In this case, the large area of ​​the base plate will prevent subsidence of the building, reducing its specific pressure on the ground.

Slab technology can also be used on dense soils, when it is necessary to combine the foundation and subfloors to optimize work. Such a need may arise during the construction of bathhouses, garages or warehouses.

Having become familiar with the features various designs foundations and the criteria for their selection, a private developer can independently install a high-quality foundation for his brick house.

Calculation of the depth of a strip foundation for a two-story house

The foundation is the basis of any structure, so it is extremely important to avoid even the slightest mistakes when arranging it. A well-made foundation will not only strengthen the structure, but also extend its service life. The construction of a two-story house also begins with the development of the foundation, but first you need to examine the soil for its condition and the height of the ground aquifers. Such geodetic studies are required in order to calculate what depth and height are needed for the foundation of the future house.

Determining the depth for a two-story house

To determine the depth of the foundation, not only the type of soil and the height of the aquifers are calculated, but also the freezing point of the soil. In particular, several types of soil are divided:

1. Heaving is fine sandstone, loam and other light compositions.
2. Non-heaving ones are semi-rocky and rocky rocks.
3. Slightly heaving ones are considered heavier. This includes gravelly (large and medium-sized) as well as coarse soils.

Important! A strip foundation for a two-story house on slightly heaving soils will take up not only strength, but also finances. Therefore, it is better to choose any other type of foundation

The height of the approach of ground aquifers also affects the size of the foundation for a two-story house. If the exit point is close and there is heaving soil, the depth should be as small as possible. And such a combination threatens with high costs and the choice of non-standard solutions. However, the good thing about a strip foundation is that it can be buried 0.7 meters and still be confident in the strength of the foundation. Additional work that will be required is not the most complex - waterproofing the supporting structure.

Advice! Semi-rocky and rocky soils do not depend on the approach of aquifers and the freezing point. Therefore, geodetic surveys are not required here, and the depth of laying the load-bearing foundation can be standard.

The freezing point of the soil is the last criterion in choosing the depth of the load-bearing foundation for a two-story house. But there is a secret here: in the case of non-heaving soil on the site, the freezing point does not have much influence.

Calculation of the depth and width of the foundation for a two-story house

After determining the main factors, the main parameters of the supporting base are calculated: depth, width, height of the strip foundation.

Advice! In the case of constructing a two-story frame house, the trench depth is calculated using the standard parameters of a frame with a height of 70 cm.

As a rule, the width of the base of the house is determined as the estimated thickness of the external walls plus 15 cm. But such calculations are very approximate; in order to determine more accurate parameters, the following data must be taken into account:

1. The area of ​​the bottom of the pit, to determine the dimensions of which it is necessary to know the mass of the structure and load-bearing capacity;
2. Thickness of the main walls of the building;
3. Soil looseness;
4. Freezing point.

Advice! The depth of the load-bearing foundation also depends on the materials used to build the house, climatic conditions and the construction site. A two-story house is considered a low-rise type of building, so materials such as brick or cinder block are quite suitable. The strip foundation for such houses can be of a shallow type.

Formula for calculation: 0.8 m multiplied by the number of floors of the future house. The resulting figure is 1.6 - this is the depth that is considered standard for a two-story house.

Features of strip foundation

The strip foundation is of the monolithic type and is ideal on sandy, clay soils. It is also used on soils with differences of 20-50 cm. The difference between this type of load-bearing base is its location along the entire perimeter of the building, including load-bearing walls.

The width of the base must exceed the thickness of the walls, taking into account the maximum load on the soil for the existing type of soil. The thickness depends on the construction material. For example, if using concrete, the base width is taken as standard - 25 cm, reinforced concrete - 10 cm wide, natural stone - 50 cm wide.

When determining what exactly the depth of the foundation should be, it is worth paying attention to the type of structure. In particular, for wooden buildings, a burial height of no more than 15-20 cm below the freezing point of the soil is selected, but for a heavier two-story brick house, a burial height of 30-40 cm below the freezing level is required.

Advice! After the depth of the supporting base is determined, the height is calculated. Dimensions vary at the request of the customer, but the standards offer their own parameters: for houses made of brick or aerated concrete, the height is from 20 cm, for wood from 35-40 cm. Builders recommend taking the following parameters: plus 10 cm to the height of the snow cover characteristic of the area

Options for installing foundations for a brick house

Based on experience in construction, a strip foundation for the construction of a brick house is best option. Under one condition, that a one-story building is being erected and a suitable type of soil is present. Bookmark two-story building requires a more careful approach and calculations of the entire supporting structure.

You always want to decorate your cottage with the most modern materials that weigh quite a bit. For example, polymer tiles weigh 17-28 kg each. Plus the supporting structure has sufficient weight. Therefore, the strength reserve should be sufficient (15-20%).

The technological process of constructing a foundation requires careful study and implementation of all advanced technologies. Let's try to disassemble not only the strip foundation for a brick house, but also a combined method. How to strengthen the foundation under two-story option. What is most important for a fortress? Technology, materials, or correctly carried out calculations and strict adherence to the project during construction.

Construction and choice of construction site

In general, you can build anywhere, but not everywhere there is suitable soil.

You can visually determine with a 90% probability only the presence of groundwater by briefly examining the vegetation.

There should be no sow thistle, reeds, or large thickets of bushes.

When choosing a site for building a house, invite a specialist to carry out geodetic surveys, thereby solving more than one issue.

Determine the type of soil, its density, and the presence of groundwater.

What type of foundation to choose

A strip foundation of normal depth is the standard. The main supporting structure rests on the top layer of soil. On dense soil when the earth moves, a strip foundation with a standard depth of up to 1400 mm works normally. Just like any other type.

Shallow foundations from this series are also made from concrete and reinforcement, and the supporting frame simply lies on the ground, the laying depth is up to 600 mm. And the main weight loads are transferred to the ground by the weight of the building and pressure. This is a floating foundation type. It is better to choose it for the construction of a one-story, light building on slightly heaving soil. An excellent choice for country or suburban construction.

The pile-tape version of foundation construction, laid using the TISE (Individual Construction Ecological Technology) construction technology, is used more often for movements on heaving soils. To prevent the tape from being torn off the piles, a stabilizing cushion is made under it. This combined use provides advantages where the depth of dense soil is below the level of 2.0-2.5 meters.

This type is suitable for building a two-story brick house, but only with light finishing on the inside.

Building in a swampy area must adhere to certain standards, and the use of a foundation that stands on screw piles, will perfectly protect the building from all kinds of distortions and shrinkage. You can also use screwing in piles; they are driven to the required depth into the soil itself, trying to get below the groundwater level, which gives undeniable advantages in stability.

This foundation is suitable for building a two-story house on stable soils. The foundation on screw piles almost does not react to the changing seasons, the building will last quite a long time.

Preparing and arranging a crushed stone cushion

Having decided the issue of number of storeys and choosing the type of strip foundation, the time comes to develop the soil and install a cushion under the strip foundation for your brick house.

The width of the ditch must correspond to the loads under a one-story building, but not less than 500 mm in width. The burial depth when building a brick house is 1-1.2 meters.

When taking into account the depth, they dig 1300 mm, of which 100 mm will go to filling the pillow with crushed stone. Compaction of the ditch bottom is done manually or using vibrating plates weighing at least 120 kg. 8-10 passes of such a slab along the bottom of the trench are enough.

For a brick two-story house, the strip foundation is poured deeper, the soil is excavated to a depth of 2 meters or more, to dense layers of earth. With the combined method, the piles are buried directly in the ditch to a depth of up to 5 meters. Installation of piles should be carried out strictly in a vertical position, and their diameter when laying should not be less than 1800-200 mm.

Tip: You can reduce the pressure on the foundation walls using damping backfills, sand, crushed stone or a mixture thereof. They are arranged around the entire base, with a layer thickness of 200-400 mm, to the depth of the entire foundation.

How to reinforce a strip foundation

Technologies are moving forward in construction as well. Recently, non-rusting fittings made of basalt fiber on a composite floor have appeared on the materials market. Its fibers are strong enough to create load-bearing structures even for a two-story house.

In lowlands and damp places it is better to give preference to it. To be sure, laying a rod with a diameter of not 12 mm, but 14. Under normal conditions, a standard frame made of Class A-3 reinforcement, made of metal, is used to strengthen the concrete structure.

In the case of reinforcing a mine field under a pile-strip foundation, a rod diameter of 10-12 mm is used to construct vertical frames. Wrapping them with rings of thin reinforcement 6-8 mm in diameter. The rings are mounted in increments of 30-40 cm, along the length of the rods. Releases are also important; for ligating with a tape frame, it is easier to cut off unnecessary ones before pouring than to tie up the pieces inside the spatial frame itself.

Important: For the installation of strip foundations for a two-story house, reinforcement is best carried out in accordance with the standards 7.3.5 SNiP 52-01-2003, “Concrete and reinforced concrete structures.” And the protective layer of concrete from the edge of the finished reinforcement frame must be at least 35 mm.

When laying a two-story house, the foundation should have not four longitudinal rods in the concrete cross-section, but at least 6. 14-18 mm thick, with a foundation cross-section of 1200 * 600 mm. To adhere to the protective layer within a given range, you can use plastic products: distances.

Under a brick house, reinforcement is simply necessary. This is not a lightweight structure made of profiles and profiled sheets. Where can you make a shallowly recessed version of the base.

Selection of formwork

The speed of the pouring work as a whole depends on the formwork arrangement. It is economical to choose a non-removable option. But for 2 floors, the best option would be block formwork made of metal or a modular option made of plastic.

The design of such equipment allows you to work in a pit without any problems, and it can be assembled in just a few days.

Many developers are in a hurry to dismantle the formwork; this should not be done. You will break off the edges of the unset concrete. You can speed up the process by adding an additive or plasticizer to the concrete, but in winter you will have to do this anyway.

For small volumes of concreting up to 20 cubic meters, it is better to make the formwork yourself from boards and timber, but in other cases it is cost-effective to rent it.

Don't forget to lay the film between the wooden formwork and the frame. If you choose metal formwork, lubricate it with waste oil, any kind will do.

Pouring the foundation tape

You can pour the tape manually using a concrete mixer, placing several auxiliary galvanized steel gutters around the perimeter. If its depth is no more than 600 mm, and its volume is 5-9 cubic meters.

Important: A pile strip foundation for a brick house is built in 2 main stages: filling the shafts or screwing in the piles and pouring the supporting strip with concrete. If the piles are made of concrete, then they can be loaded no earlier than after 30 days.

In another case, concrete must be ordered in advance, calculating the exact volume. Deep vibrators for compacting the mass itself are also useful here; the denser the tamper, the better the quality of the concrete.

Pouring load-bearing structures with concrete requires experience and knowledge. By agreeing with specialists, you will perfectly solve the problem of assembling all structures, and also solve the issue of concreting.

Foundation for a two-story brick house

Any structure requires strong support; this element can serve as the foundation for a two-story house.

When laying this structure, it is important to avoid defects and errors in order to extend its service life.

To do this, you should thoroughly examine the soil in order to select the most suitable type of foundation.

Basic soil indicators

To determine the depth of the foundation for a two-story brick house, you must have the following data:

• type of soil;
• soil freezing depth;
• depth groundwater.

Before laying the foundation, determine the soil type

The soil water level is at a great distance from the freezing level (more than 2 meters). For this reason, building a foundation will not be expensive.

Soil type is one of the important factors influencing the depth and choice of material to fill the foundation. The soil changes its volume under the influence of weather conditions, therefore, by determining its properties, it is possible to determine the classification of soil type. They are divided into:

• rocky ones are reliable, strong enough;
• coarse - a combination of sand and various solid particles, a reliable base;
• sandy - contain sand of different densities, perfectly pass water, are not subject to heaving, but shrink under load;
• clayey – the main percentage consists of clay, they retain water, can shrink or erode, and are subject to frost heaving;
• loamy - this is soil containing from 10 to 30% loam with sand, which retains moisture, which contributes to strong freezing and an increase in volume;
• peat - a mixture of clay, sand and other organic impurities, which compacts unevenly under load.

Ground water level

The groundwater level is an indicator that helps establish the depth of the foundation that is required specifically for a given type of structure. If the level indicators are high, then it is better not to use this site for construction.

After all, this can entail large costs, and during the design - incorrect decisions. In addition, additional waterproofing should be subsequently carried out.

All necessary information should be clarified before construction begins. This can be done without special geodetic research: ask neighbors, visit real estate agencies, or use the help of a company that has conducted tests in this area.

Soils that are not greatly affected by the level of freezing and rising water are rocks.

The amount of soil freezing

Many construction companies use a simplified version of determining the depth of the foundation, since they consider winter soil freezing to be the main criterion on which it depends.

To some extent, this is the right decision, but on the other hand, this method can increase the cost of work several times.

If the soil is not failing, then the amount of frost will not have much effect on the foundation, no matter how deep it is laid. But be that as it may, this factor must be taken into account.

Foundation parameters

For the construction of a brick house, the optimal depth and width of the base are important points. The basic principle that should be followed is the correct location of the foundation. It should be lower than the freezing limit in the soil.

This applies mainly to clay and loamy soils, since they tend to raise the foundation when they increase in volume. This also leads to the appearance of cracks, and subsequently contributes to the destruction of the structure.

Sandy soil does not swell, so there is no need to lay the foundation below the freezing mark. In this case, the depth of the foundation will depend on the supporting capacity of the soil and the structural load.

The depth is calculated using a special formula that takes into account the critical temperature indicator, the length of time with this temperature during the month, as well as the type of soil.

To determine what soil freezing depth is present, you can refer to the table, which shows data by region.

Other Important Points

It is also necessary to pay attention to the presence of a drainage system, in particular when it is planned to build a house next to a reservoir where the level of soil water is high.

This fact is also worth considering if the house is planned to be built with a basement.

In order for a brick house built on several floors to have the correct foundation, you should study all the conditions that may affect further operation:

• compare the load on the base with the standards;
• the height, width and thickness of the planned building are necessary to calculate the load-bearing capacity of the entire system;
• minimum width of the sole of the support system;
• number of floors.

To determine the required depth, the following formula should be followed: 0.8 m multiplied by the planned number of floors. For a house with two floors, the value will be 1.6 m. For more information about drainage work on the site, see this video:

For long-term operation, the construction and arrangement work must be carried out correctly, which will preserve the house without distortions, various cracks and other damage.

Features when determining the size of the base

The width and height of the foundation when calculating require identifying certain characteristics. To build a brick house with several floors, you need to lay the tape to the frost line. But for greater strength, it is better to make the depth of the pit 30 cm larger so that the height of the strip base above the zero point is appropriate.

What the width of the base will be depends on the size of the house. The following parameters play an important role in determining this indicator:

• sole area;
• dimensions of the thickness of the walls of the structure;
• the weight of the reinforced frame of the tape, as well as the width and correct spacing between the reinforcement.

What should the strip foundation be like? Durable so that after completion of the work, taking into account all total loads, the structure does not sink into the ground. After all, a structure can not only push the structure out during frosts, but also be pressed into the soil under the influence of heavy weight.

Correct consideration of all parameters when calculating a strip foundation is the key to long-term and reliable operation of the structure.

Strip foundation

Given many years of practice, it is not practical to use a pile foundation for a two-story brick house. After all, for this you need to rent special equipment. Large investments are required to transport piles and install monolithic grillages. The most common type for brick buildings are strip foundations. In most cases, prefabricated or monolithic structures are used.

The prefabricated base, as a rule, includes concrete blocks and reinforced concrete slabs, the thickness of which is about 50 cm. To learn how to make a strip foundation with your own hands, watch this useful video:

To prevent the structure from being pushed out by the soil, expansion is performed at the base. For small elements this process is done using metal rods. When constructing a building at the junction of the strip base and walls, it is necessary to install a polyvinyl chloride film and perform insulation.

What is the standard for the foundation when building a two-story house? These are poured structures that are made of concrete with the addition of crushed stone or gravel. The prepared solution must be poured into pre-made formwork and compacted.

Foundation depth for a two-story house

The foundation is the basis of any structure. Therefore, it is very important to avoid mistakes when laying it out. A well-made foundation will strengthen the structure and significantly extend its service life. Let's say you want to build a two-story house. Where should I start? Start with geodetic research to find out the type of soil and the height of the groundwater rise. This must be done in order to correctly calculate the laying depth and determine the type of foundation most suitable for the given area. The depth of the foundation for a two-story house is one of the most important characteristics that need to be determined. Let's look at this in more detail.

Dependence on soil type

So, we have learned that how deep any foundation needs to be laid is influenced by three main factors:

• Soil type,
• Groundwater level,
• Soil freezing depth.

To know how deep to dig a foundation, you first need to determine the type of soil in your chosen area. The type of soil is one of the fundamental factors that influence both the building material and the depth of installation and the type of foundation that is best used in given conditions.

The fact is that soil can change its volume depending on weather conditions. Based on this property, there is a classification of soil types. They are divided into three types:

1. Heaving soils. These include fine sandy soil, loams and others.
2. Non-heaving soils. These include semi-rocky and rocky rocks.
3. Slightly heaving soils. These include large and medium gravelly sands and coarse soils.

Dependence on groundwater level

Another factor, the determination of which will help determine what depth of foundation is needed specifically for your building, is the groundwater level. If the site you have chosen for construction is too high and the soil is heaving, then this is not the best option for construction. This combination promises increased costs and non-standard solutions when designing a building. Most likely, additional waterproofing will be needed for the supporting structure. Therefore, it is best not to stop your choice on such areas. Be sure to find out this information before you begin construction. This can be done without any geodetic surveys. Interview the owners of nearby plots, visit real estate agencies, or contact companies that study and test the soil in the area.

There are also a number of soil types that are not significantly affected by either winter freezing of the soil or the height of groundwater rise. Such types of soil are, for example, semi-rocky and rocky rocks.

Dependence on soil freezing depth

Almost all construction companies use a lightweight method for determining the optimal foundation depth. They believe that main criterion, on which the depth of the foundation for a house depends - this is the depth of soil freezing in winter. On the one hand, this is absolutely correct, but on the other, this approach sometimes increases the cost construction work in many times. Why is this happening? The fact is that such developers do not take into account the type of soil. If the soil, for example, is not heaving, then the force of frost heaving will not have any effect on the foundation, no matter how deep it is laid.

But still this factor should be taken into account. It depends on the climate of the area in which the house is being built. For example, the depth of soil freezing in Moscow is 140 cm, and in Novosibirsk – 220 cm.

Calculation of the depth and width of the foundation for a 2-story house

Any work on building a house begins with digging a trench. Since the planned building has only two floors, the load on its foundation will be relatively small. Consequently, the width of the trench can be no more than half a meter. As for the depth of the trench, it must be made as large as possible. This will only enhance the load-bearing capacity of the structure.

If you plan to build a frame house, then when calculating the depth of the trench you need to take into account the dimensions of the frame for a two-story building, the height of which is 70 cm. When the trench is ready, you can begin installing the formwork. And then you need to make a frame from reinforcement, welded or wire.

The depth and width of the foundation depend on many parameters. Some builders determine the width of the base of the house as the estimated thickness of the walls, adding 15 cm. But these are very rough calculations. To calculate the width more accurately, you need to take into account data such as:

1. The area of ​​the base of the pit, to calculate which it is necessary to know the weight of the entire structure and its load-bearing capacity.
2. The thickness of the main walls of the building.
3. Soil looseness.
4. The depth to which the soil freezes in winter.

The depth of the foundation is determined based on information about the material used to build the house, the characteristics of this type of soil and the climatic conditions in the area where the building is being built.

A two-story building is considered low-rise, so the material for it could well be brick or cinder block. As for the type of foundation that is suitable for low-rise buildings, it can be shallow.

The foundation depth is calculated using the following formula: 0.8 m multiplied by the number of floors in the future house. Thus, for a two-story building this value will be equal to 1.6 m.

Foundation types

Used in construction Various types foundation, the choice of which depends on many factors.

Tape

The tape type is monolithic and is suitable for use on clayey, very sandy soils. It can only be used if there are differences in soil height from 20 cm to 50 cm on a plot of land. The main difference between a strip foundation and other types is that it is placed under the entire area of ​​the house, including load-bearing walls.

The width of this type of foundation must exceed the thickness of the walls of the building. In addition, when determining it, the maximum load on the soil for a given type of soil is taken into account. Its thickness depends on the material used. For example, if concrete is used, the thickness will be 25 cm, reinforced concrete - 10 cm, natural stone - 50 cm, etc.

To find out what depth of the strip foundation will be optimal, you need to pay attention to the type of structure. For example, for wooden structures, a shallow strip foundation is most often used, while for heavier concrete structures it is better to use a buried one. It should be located 20-30 cm below the freezing point of the soil in your chosen area.

The material for strip foundations is traditionally rubble stone or brick.

Pile

Pile foundation is the type most popular in construction. Its main advantages are strength and lack of deformation. The piles of which it consists are usually made of heavy concrete and reinforcement with an anti-corrosion coating. Piles are made in such a way that they can withstand the load when they are installed; they are driven into the soil. Before releasing products for sale, they are carefully checked and tested.

Piles are the strongest material used to build a house today. They are suitable for the construction of buildings even in areas with weak soil. For each type of soil, a different type of pile is used.

The depth of the pile foundation should be from four meters for a one-story building and up to eight meters for two-story buildings and buildings with more than two floors.

Columnar

This type of foundation, and especially its subtype - the support-column one, is most suitable for small buildings. It is one of the cheapest and least labor-intensive used in construction today. It can be laid even in winter, but at a temperature not lower than 10°C.

The depth of the columnar foundation may change if parameters such as:

• The depth of soil freezing in a given area. Columnar foundation always laid below this depth.
• Soil type and composition. It is better if it is sandy soil.
• Groundwater rise level. If the level is too high, additional soil drainage and waterproofing must be done.
• The weight of the building itself and the load it puts on the load-bearing part.

Concrete pillars are dug in along the entire perimeter of the base and in the locations of the load-bearing floor beams. The distance between them should be about 2 m. They are covered with roofing felt on top, which ensures reliable waterproofing.

Thus, we see that the depth of the foundation for a two-story house can be different and depends on many extraneous factors.

Brick remains a popular building material, despite the presence of many alternative technologies used in private housing construction. Brick houses are famous not only for their spectacular appearance, but also good quality; their successful long-term operation is largely determined by the properties of the foundation. Modern construction techniques make it possible to lay a high-quality foundation for a brick house, capable of adequately bearing the weight of a one- or two-story structure.

A capital structure needs a capital foundation Source remontik.org

Factors influencing the choice of foundation

The foundation of any building is designed to take on the weight of the structure, support it without deformation and transfer it to the underlying soil. A brick house is one of the most problematic buildings; not all types of foundations are suitable for it. The reason lies in the impressive mass of brick walls.

With an external wall thickness of 640 mm (thermal technical standard) and a height of 3 m, the mass of a linear meter of one floor will be 3460 kg. For comparison, a linear meter of a wall made of foam concrete (500 mm) will weigh 1350 kg, and one made of wood (300 mm) - 470 kg. It is clear that brick walls exert a serious load, and therefore strict requirements are imposed on the choice of foundation.

When designing, the foundation for a brick house is calculated based on several initial data. The calculations are influenced by both the characteristics of the house itself and some external reasons. The following factors are taken into account:

(depending on area, number of floors, wall thickness).

The walls place the main load on the foundation Source bg.decorexpro.com

Physico-mechanical characteristics of the soil on the building site. The soil can have different densities (which determines the calculation of the permissible load), be natural or bulk. The foundation on heaving soil is designed especially carefully.

Soil water saturation. It depends on the groundwater level and affects the depth of soil freezing.

Shrinkage of brick buildings

Most people are of the mistaken opinion that only wooden structures are at risk of deformation, while brick buildings are free from such problems. In fact, the concept of shrinkage of a brick house is known to all professional builders; This refers to the shrinkage of the foundation. Since the weight of load-bearing walls reaches significant values, shrinkage can also become significant and lead to the appearance of cracks in the walls. The intensity of shrinkage is determined by the properties of the soil - the softer it is, the more the foundation of the house will sink. To reduce negative processes, a cushion is laid under the foundation of the building - a layer of concrete, sand or crushed stone.

Consequences of uneven shrinkage Source stroi-x.com

Shrinkage period country house made of brick can take several years (sometimes 5-6 years). To ensure that the process proceeds evenly and does not violate the integrity of the building, the importance of selecting the right foundation. Special technological techniques during the construction of walls also help to avoid cracks. IN brickwork special expansion joints are left. They last for one to two years and serve as a good preventive measure against the occurrence of not only shrinkage cracks, but also temperature cracks.

After the project has been prepared and a clear understanding of the objective conditions has been obtained construction site, the type of base is determined. Three types of foundations can support a two-story brick house: strip, pile and slab.

Strip foundation of a brick house

Visually, the strip-type foundation fully corresponds to the name. It has the form of a contour reinforced concrete strip running along the perimeter of the house (under the load-bearing walls) and under the internal partitions. The tape type has become widespread due to the following advantages:

Ease of execution.

Construction of a strip foundation Source stroy-dom-pravilno.ru

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

Durability. Service life exceeds 50 years.

Capabilities .

Applicability for any projects. Base strips can be used as wall structures for a basement or ground floor.

The disadvantages of the tape type are its following features:

Cost. Significant material, time and human resources are required.

Restrictions. Strip foundations are not used on some soil types. It also imposes restrictions on the choice of architectural form of the building. The depth of the strip foundation for a two-story house is determined for each project individually, based on its features and the characteristics of the site.

The basis of quality is a properly poured concrete mixture Source nearsay.com

There are several types of strip foundations:

Monolithic. Solid concrete structure, the most durable and therefore the most common option for brick buildings; the weight of the structure on such a foundation is distributed evenly. A trench is dug along a given perimeter, a cushion of crushed stone and sand is laid on the bottom, a layer of waterproofing is installed, and wooden formwork (bounding surfaces) is installed. A reinforcing belt is installed (steel reinforcement secured in a special way). The concrete solution is poured into the formwork and further compacted. The disadvantage of this method is that you have to wait until the concrete mixture hardens and gets stronger.

Prefabricated (block). Finished reinforced concrete blocks are laid in the order specified by the project in a trench and fixed. The disadvantage of this method is the need to use special equipment to move individual elements. A prefabricated base is less durable than a monolithic one

Shallow-buried. It is not suitable for two-story buildings made of stone or brick, since it goes into the ground a little more than half a meter.

Scheme of a prefabricated strip foundation Source remoo.ru

A monolithic foundation can be constructed in two ways:

If the house project provides a basement or basement room, then at the first stage a pit is dug, at the bottom of which a reinforced concrete layer is constructed. After it hardens, the basement walls are erected. Such a foundation turns out to be the most reliable; it is designed for two- and three-story brick buildings.

If the project of a two-story brick house does not provide a basement, a standard strip base is installed. Its depth is determined by increasing the depth of soil freezing by 30-40 cm.

Online foundation calculator

To find out the approximate cost of a strip foundation, use the following calculator:

Pile foundation

A pile foundation for a brick house, a two-story or one-story project, is designed for an area with fragile, crumbling soil, and is characterized by the following parameters:

Using piles helps transfer the main load from the building deeper, durable soil layers, bypassing the unreliable top layer.

Top of piles, remaining on the surface, contacts into a single structural element with help reinforced concrete grillage . The building rests on this contour, but most of the load is carried safely on the piles.

Fragment of a pile foundation Source domvita.ru

The pile method involves use of special equipment for drilling wells and installing piles. This leads to additional costs, but is compensated by the speed of installation and ease of installation.

Use of piles economically justified in areas with dense soil. The method allows you to equip a foundation designed for fairly high loads, and the calculations must be carried out very accurately.

Use of piles not economically justified during construction on water-saturated soil. In order for the foundation to fully support a two-story brick building, it will need to be strengthened. As a rule, this will require an increase in the number of piles. It will be necessary to use piles of larger cross-section and immerse them to greater depths. In addition, a powerful grillage contour for cutting the piles will be required. Such changes can negate the efficiency of the pile method.

Online foundation calculator

To find out the approximate cost of a “grillage on piles” foundation, use the following calculator:

Video description

About the types and properties of foundations in the following video:

Slab (monolithic) foundation

A good way to arrange the foundation of a two-story brick house. Such a foundation looks like a solid reinforced concrete slab on which the frame of the house is built. It is characterized by the following parameters:

Laying depth. There are deep foundations (from a meter or deeper), shallow foundations (0.5-1 m) and non-buried foundations (up to 0.5 m).

Duration of operation. It is the highest when compared with other types; the base is designed for 60-70 years of flawless service.

Use on problematic soils. An ideal solution for heaving, weak and waterlogged soil.

Minuses. The slab type is characterized by high construction costs and high time costs.

Online foundation calculator

To find out the approximate cost of a slab foundation, use the following calculator:

Slab foundation with reinforcement belt Source kummer-bau.at

Choosing a foundation and ways to strengthen it

The foundation of a two-story brick house is subject to special requirements in terms of strength and depth parameters. In most cases, the choice is made as follows:

If the soil not problematic, is selected strip foundation. It is made deeply recessed, and a wider grillage, according to calculations, is also laid.

If the soil is on a construction site heaving(changes its volume during the annual freezing-thawing process) preference is given pile foundation , capable of providing a significant margin of safety. Reinforced concrete pillars with a large cross-section are chosen for it, and only reinforced concrete grillage is laid. If a strip block (prefabricated) foundation is chosen, it is installed below the freezing layer, or the heaving soil is replaced with a backfill of sand or crushed stone.

If the soil wet, heaving or crumbling, the optimal choice would be deep slab foundation.

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:

If on site high groundwater level, foundation complemented by a drainage system along the perimeter. If the project has a basement or ground floor, waterproofing protection is enhanced. If there is no basement, the foundation (either strip or pile is suitable) is installed above the groundwater level.

If the soil on the site has low density (weak, unstable soil or landslide zone), use special pile method. To arrange the base, special piles are used (with a screw profile or pockets), and the soil is additionally strengthened by injection of cement mortar, liquid glass or bitumen.

If a house is being built in a potentially seismically active zone, and the soil has normal characteristics, development is allowed monolithic strip base(without additional reinforcement). The main condition is that for the foundation of a two-story brick house, high-strength concrete grades are used and reinforced reinforcement is carried out. Such measures help protect the structure from possible tremors.

Deep foundation diagram Source kamtehnopark.ru

Sometimes there is a need to strengthen the foundation of a brick house. This can be done in a variety of ways, including:

Enhancement by injections. The soil around the base is removed, and a cement solution is applied to the exposed base (special equipment is used).

Reinforcement with piles. Piles are installed along the foundation.

Reinforcement with reinforced concrete frame. Formwork is installed around the perimeter, a reinforcing belt is installed and concrete mixture is poured.

Reinforcement with a protective wall. The outer wall is made of concrete, sometimes it rises to a height of up to one meter.

Gain reinforced concrete slab Source palazzo.su

Principles of foundation calculations

The foundation for any buildings, including brick ones, is described by several parameters:

Deepening. It is selected based on an analysis of the soil (density and bearing capacity) and freezing depth. There are tables relating soil type and recommended depth.

. It is calculated based on the total weight of the brick house. To do this, structural (walls, partitions, roofing, floors), internal (people and furniture) and external (snow on the roof) loads are summed up.

Necessary (minimum) support area and base width. The total area of ​​the concrete strip is determined by the bearing capacity of the soil and the load on the soil of the building along with the foundation. Knowing the area and perimeter, you can, by dividing the first by the second, calculate the width of the strip base.

A high-quality foundation will give a house a long life Source sever-dom.su

On our website you can get acquainted with the most popular projects of brick houses and cottages from construction companies presented at the exhibition of Low-Rise Country houses.

Conclusion

For each house, the foundation of the most suitable structure is selected and designed, and it often turns out to be combined. Based on objective reasons, the designer can use elements of several types: it often becomes advisable to reinforce a traditional strip foundation with piles. Strength is also enhanced by the use of modern materials for insulation and waterproofing.