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

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

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

Preparatory stage

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

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

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

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

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

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

Types of foundations

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

• ribbon;
• combined options.

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

There are three types of pile foundation for a house:

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

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

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

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

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

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

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

How to pour a foundation for a house

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

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

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

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

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

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

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

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

Step-by-step instructions for pouring a strip foundation

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

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

• ground leveling;
• prevention of frost heaving;

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

The foundation is the first, most important and quite expensive stage of building a house. Sometimes this is 30% of all costs. To save money, you might consider making your own foundation. Of course, it is very difficult to pour the foundation for a multi-story mansion on your own. But for an ordinary dacha this is quite possible.

Construction of the foundation of a house

The word "foundation" comes from the Latin "fundamentum" - foundation. It is a fundamental part of any building. You can invest huge amounts of money in a house, but if the foundation is bad, then the house, even on the most solid soil, will float, crack, and collapse.

A foundation is an underground or underwater part of a structure that transfers to its soil foundation the static load created by the weight of the structure, and additional dynamic loads created by the wind or the movement of water, people, equipment or vehicles. A properly designed foundation transfers all loads to the ground in such a way that the possibility of unacceptable settlement and destruction of the structure is eliminated.

Collier's Encyclopedia

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Which one is more suitable?

You can build the foundation yourself, and it’s not difficult to understand the drawings and calculations. Moreover, there are not so many types of foundations, and they are strictly tied to the types of soil and the weight of your house.

This is how a foundation of stones and concrete is built in Goa, India; photo by Jorge Royan

The foundation is bad when it is built without regard to the soil; there were violations in its design or simplifications were introduced into initially correct calculations; you tried to save on materials or violated the pouring technology. To prevent this from happening, let's consider everything in order.

Kinds

There are only four main types of foundations; they differ structurally:

1. Tape.

   Diagram of a strip foundation - it clearly shows the sequence of its construction and specification

2. Columnar.

   Diagram of a columnar foundation - it clearly shows the sequence of its construction and specification

3. Slab.

   Diagram of a slab foundation - it clearly shows the sequence of its construction with the laying of reinforcement and specification

4. Pile.

   Foundation diagram on screw piles - all specifications and principles of construction are clearly visible

But among them there are also a lot of varieties, and there are foundations combined in shape.

The construction is regulated by a number of reference books; absolutely everything is covered in them.

SNiP - building codes and regulations

• SP (Code of Rules)
  • SP 24.13330.2011 (Updated edition of SNiP 2.02.03–85, 1995, as amended - 2003, text) “Pile foundations”;
  • SP 50–101–2004 “Design and installation of foundations and foundations of buildings and structures”;
  • SP 50–102–2003 “Design and installation of pile foundations”;
• SNiP (Building Norms and Rules)
  • SNiP 2.02.04–88 “Foundations and foundations on permafrost soils”;
  • SNiP 2.02.05–87 “Foundations of machines with dynamic loads”;
  • SNiP 52–01–2003 “Concrete and reinforced concrete structures”;
• GOST (State standard)
  • GOST 13580–85 “Reinforced concrete slabs for strip foundations. Technical conditions";
  • GOST 23972–80 “Reinforced concrete foundations for parabolic trays. Technical conditions";
  • GOST 24022–80 “Prefabricated reinforced concrete foundations for columns of agricultural buildings. Technical conditions";
  • GOST 24476–80 “Prefabricated reinforced concrete foundations for cross-type frame columns for multi-storey buildings. Technical conditions";
  • GOST 28737–90 “Reinforced concrete foundation beams for walls of buildings of industrial and agricultural enterprises. Technical conditions.
  • GOST 24846–2012 Soils. Methods for measuring deformations of the foundations of buildings and structures";
• MGSN (Moscow city building codes) 2.07–01 “Foundations, foundations and underground structures”;
• Normative literature related to the topic
  • SNiP 2.02.01–83* “Foundations of buildings and structures”;
  • SNiP 3.02.01–87 “Earth structures, foundations and foundations”;
  • “Manual for designing foundations of buildings and structures” (to SNiP 2.02.01–83);
  • GOST 24379.0–2012 “Foundation bolts. General technical conditions";
  • GOST 24379.1–80 “Foundation bolts. General technical conditions. Design and dimensions."

Foundation structure

All varieties have common features. These are penetration into the soil, a cushion of drainage material (crushed stone, sand, pebbles), the foundation itself and waterproofing. Only pile types do not have a cushion, and only if they do not have a recessed grillage.

Photo gallery: drawings of different types

A slab foundation (drawing) shows the principles and technology of its construction. A strip foundation (drawing) of two types: made of aerated concrete blocks and concrete: similarities and differences. Similarities and differences between a pile foundation made from different types of piles. A column foundation (drawing in two positions) shows the principles of its construction. Drawing slab foundation with insulation and full specification Drawing of a slab foundation with insulation and drainage (and full specification)

Soil mechanics

The choice of foundation primarily depends on the characteristics of the soil: its composition, depth of freezing and groundwater, and only then on the design of the house and its materials.

The type of foundation is selected depending on the soil

Soils

The contact area of ​​the foundation with the soil must correspond to the load, taking into account the expected resistance of the soil. The maximum resistance (reactive pressure) of the soil is determined experimentally based on the principles of soil mechanics, and state building codes provide tables of permissible soil resistance for certain geographic zones.

Collier's Encyclopedia

http://dic.academic.ru/

Before designing a house, it is better to order a professional survey of the site. Moreover, you should not use the results of your neighbor: sometimes even neighboring areas differ greatly in their characteristics. But you can do it yourself: dig a hole from half a meter to a meter deep, then use a garden drill to make a hole two meters deep, studying the soil from different depths.

If the site is located in a populated village, then it is good to talk with the owners of neighboring sites and look at their sites. This will help a lot.

According to the reference book “Soils. Foundations. Choosing the optimal foundation” There are three types of soils:

• rocky - massifs of homogeneous crystalline rock (rock) and sedimentary layered rock: dolomite, shale, sandstone, limestone;
• conglomerate - any soil with a large percentage (more than half) of fragments of crystalline or layered sedimentary rocks;
• non-rocky, which in turn is divided into
  • bound - loams and clays;
  • unbound - sands and sandy loams.

The classification of soils is clearly shown in the diagram

Soil cohesion also changes depending on humidity. Soil connectivity is independently determined visually - by the angle between the slope of the soil thrown out of the pit and the horizontal.

Our strip is characterized by non-rocky soils.

If your soil is virgin sandstone or gravel, then you are lucky (even luckier if it is rocky). Sand is a wonderful base for the home. It is quite reliable if the soil is plastic, dense and dry loam, or gravel, or even compacted construction waste. The trouble is that clays are never completely dry, and wet clay tends to swell and bulge.

Table: minimum depth of the foundation structure for construction in sandy and clayey soil

If it is easily and unevenly compressible soil - forest or garden fill soil, or, what is much worse - swampy soil, then your construction will cost you much more due to the forced compensation for these problems. In the case of quicksand (resembling dust or flour) or silt, building a house is not advisable at all.

Freezing

In addition to the composition of the soil, you need to know to what depth it freezes in winter. In our “latitudes” the freezing depth is usually from eighty to one hundred centimeters.

The base of the foundation should be below the maximum freezing depth of the soil to prevent swelling of the soil when freezing. The safe depth depends on annual temperature variations, the type and range of local soil variations, and the normal groundwater level. In addition, seasonal changes in the volume of clay soils are sometimes observed, which should not be allowed under a foundation laid on a natural foundation.

Collier's Encyclopedia

http://dic.academic.ru/

Ground water level

This is also an indicator on which not only the “model” of the foundation depends, but also the depth of its laying; it is assessed in relation to the depth of soil freezing. If in winter the water does not rise below 2 meters to the freezing depth (for brevity, let’s denote it by the letter Q), and your soil is fine and silty sand or hard clay, then the depth of the foundation will not depend on the freezing depth in principle.

Table: dependence of foundation laying depth on groundwater depth

But if the soil in the area is mixed, and there is sand or peat on top of the clay, then after precipitation, so-called “lenses” appear inside the soil - moisture seeps from above through the permeable layer and falls on the impenetrable clay. And this is very dangerous for the foundation due to its unpredictability.

Diagram of soil permeable from above, which creates internal “lenses” of water that are very dangerous for construction

Therefore, it is better to order a full survey of the site from professionals and receive a number of necessary documents about the condition of the soil. They should include the following information:

1. Topographic plan with soil water curves and different types of soil.

   An example of a topographic survey of a private land plot: it is too difficult to do on your own

2. Mechanical properties of soils: possibility of subsidence and sliding, heaving, cohesion, ability to support the foundation without special efforts.
3. Physical and chemical qualities of soils - freezing depth, wetting ability; what substances it releases when wet, and how they will affect the foundation material.
4. Diagram of groundwater depth and its changes depending on the season and temperature.

   A diagram of groundwater on a personal plot shows what type of foundation your future home needs

Type selection

Let's look at the types of foundations in more detail.

1. One of the easiest types to implement on your own is a columnar foundation. It is suitable for light wooden house structures. Such a foundation can also be shallow, but this is more suitable for gazebos and barbecues - for a house it is too ephemeral. It is placed in pits (on a bed of drainage material) made of factory-made concrete blocks. Pros: ease of implementation, low price, suitable for any soil. Cons: not suitable for heavy house structures; The underground floor is poorly insulated.

   A recessed columnar foundation made of ready-made concrete blocks is one of the simplest solutions

2. Pile columnar foundation is suitable for unstable soils and slopes. It dampens movements well and is made from asbestos-cement pipes, which are concreted into pits with drainage filler. Pros: relatively simple and cheap to construct, resistant to subsidence and landslides. Cons: the same as the previous one.

   A columnar foundation made of pipes is used on unreliable, floating and heaving soils, damping movements

3. Pile-grillage welded foundation made of metal, from ordinary and screw piles, is ideal for unreliable soils. Pros: aesthetics and reliability, high durability. Cons: very expensive due to the cost of metal for a heavy grillage and requires welding.

   The metal welded pile-grillage foundation is beautiful and reliable, but very expensive

4. Slab foundation. Excellent for unstable or subsiding soil; in addition, it is often used if the house will have a very large weight. Pros: solidity, reliability. Disadvantages: labor intensive, lack of underground, high cost.

   A monolithic slab foundation is almost ideal for a large house, but does not have a subfloor

5. Most often, the best option is a buried or shallowly buried (for light wooden houses) strip foundation. It can be made from ready-mixed concrete, cement mortar, or concrete blocks with mortar. Pros: comparative simplicity and financial accessibility of its construction. Disadvantages: it cannot be placed on unreliable soils with close soil water, on clay and sand. But almost one hundred percent of the experts will recommend it to you, even if your site consists of unfavorable soils - but with amendments to the design: it will be necessary to make the “ribbon” of the foundation wider and deeper.

   Strip concrete foundation is used more often than others due to its high functionality and not very high price.

But foundations in one form from combined materials are widespread.

Photo gallery: foundations combined in material

Strip foundation made of blocks; inside - drainage material Slab foundation made of blocks and concrete: the blocks here are permanent formwork A brick strip foundation on a concrete base is beautiful, but expensive and not very durable Slab foundation made of brick and concrete: here the brick wall plays the role of permanent formwork A strip foundation made of rubble stone and mortar will save you a lot of mortar. Options for grillages on a columnar foundation. Wooden, metal, concrete.

Components of the structure

After we have chosen the type of foundation, we need to choose what we will use: concrete or cement mortar; and - ready-made or self-made.

Concrete or cement mortar

Many people confuse these concepts and often call all poured structures concrete.

1. Cement mortar is made from cement, sand and water, and sometimes from cement, lime or clay, sand and water, in the ratio determined by SNiP. Often additives are added to it to increase strength, water and frost resistance; plasticizers that increase setting speed and viscosity.
2. Concrete is also created by mixing cement, water and fillers in a certain ratio. Instead of sand or together with sand, crushed stone, gravel, and pebbles are included in concrete. This solution produces the strongest artificial stone. Concrete is also used in the form of ready-made blocks and panels.

Components of good concrete: high-grade Portland cement, non-clayey fine river sand, fine crushed stone

You can order ready-made concrete, or you can make cement or concrete mortar yourself.

An electric cement mixer for preparing mortar will greatly facilitate the life of any craftsman.

The cement for mixing must bind the composition well, so heavy Portland cement grades M300–400 are used. The mixing ratio according to SNiP depends on the brand of cement, soil characteristics and foundation depth. Here is a useful table.

Table: ratio of cement and sand for laying foundations

Formwork

Formwork is a structure made of boards (sometimes panels) and stops, necessary for fixing the form when pouring concrete and cement structures.

Formwork for strip foundations made from edged boards is the most common solution for us

There are two types:

1. Removable - disassembled after the concrete/cement has set; formwork made of boards and chipboards can be used up to 8 times. Industrial formwork - up to several hundred times.

   The principle of constructing removable formwork from boards is the simplest

2. Non-removable remains on the concrete. This is a recent invention, they are made from polystyrene and connected with special locks. It is quite expensive, but serves as insulation, which is very practical.

   Fixed polystyrene foam formwork is connected with special locks and then serves as insulation

   Permanent formwork also includes hollow concrete blocks of various shapes, which are placed on a sand bed in a trench, connected with a metal rod and filled with concrete.

   Fixed formwork made of hollow blocks is also very convenient, although difficult to implement

Products

They are absolutely necessary to ensure that the subfloor or space under the house is ventilated, and that excess dampness, fungi and mold do not grow there. The soil releases moisture and must dry. The vents are especially relevant for the log house we have chosen, as well as for any wooden structures, but only if there is an underground space in the case of a sealed monolithic strip foundation. If the floors are laid on a slab, or the foundation is piled, there is simply no need for them.

According to SNiP 31–01–2003 (updated as SP 54.13330.2011) “Residential multi-apartment buildings” (clause 9.10), the total area of ​​vents should be 1 to 400 of the basement area, but be at least 0.8 square meters. One hole should be no less than 15x15 centimeters. If it is larger, it will require special reinforcement when pouring, so we will make smaller vents. There must be an even number of them, and they must be located opposite each other. They should be 90 centimeters or less from the corners.

The vents should be 90 centimeters or less from the corners

If there are internal foundation strips, then they should also have vents so that there are no sealed chambers left.

There should also be vents in the internal foundation strips so that there are no sealed chambers left

It is not necessary to close the vents for the winter, according to SNiP 11-3-79 “Construction Heat Engineering”, which regulate the ratio of temperatures in the underground and outdoors. It is better to insulate the floor well.

If for some reason you did not make holes when pouring the foundation, you can punch them later with a grinder or hammer drill. But this violates the integrity of the foundation and poses a difficult task.

If the vents are not made when pouring the foundation, you can punch them later with a grinder or hammer drill

You can close the vents from mice and other small animals with special grilles.

A cushion of sand, crushed stone or gravel is necessary for drainage, thermal insulation, and better placement of the mortar. For a typical strip foundation, a thickness of about 30 centimeters is sufficient.

The pillow under the foundation is clearly visible in this diagram

Waterproofing

Waterproofing can be:

• with film, lining the boards until they harden - so that the boards can then be used for other purposes (optional);

  Waterproofing formwork boards during the construction of a grillage for a pile foundation

• roofing material (on top) and bitumen mortar (the entire base can be used) after hardening - to prevent moisture from penetrating into the walls (it is strictly necessary, and it is better to use both materials).

  Waterproofing the foundation with bitumen and roofing felt is an absolutely necessary thing in construction.

Concrete is quite fragile and is unable to resist bending under uneven deformations. Reinforcement is a guarantee of the strength of the foundation, saving it from cracking and shifting.

The reinforcement diagram shows its principle and necessity

There are simple rules:

1. It is better to avoid welding or use it selectively, giving preference to tying reinforcement.

   Tying reinforcement contributes to greater flexibility of the foundation

2. The diameter of the reinforcement is 0.1% of the cross-sectional area of ​​the tape, taking into account its length. It is accepted that if the length of the tape is more than three meters, then the cross-section of the rod is 12 mm.

   Foundation reinforcement is the key to the strength of the house

3. There are also rules for determining the distance between vertical and horizontal rods and their number per linear meter.

   Determining the distance between vertical and horizontal bars

Insulation and finishing

You should not neglect the insulation of the foundation at all - you will greatly save money on heating the house and basement, and protect the house from dampness. Moreover, you can do this while pouring it, or you can do it after it has hardened. You may be pouring with polyurethane foam formwork, but you can also lay polymer panels in regular formwork. Or sheathe the finished foundation with such panels and cladding on top.

Insulation for the Penoplex foundation - polystyrene foam PSB-C 25 2000x1000x100mm - laid on a waterproofing film

The foundation itself can be finished with any material. There is endless scope for creativity here!

Blind area

Around the foundation, after building the house, it is imperative to make a blind area - a strip impenetrable to water, wider than the overhang of the eaves of the house, ideally with a well-thought-out storm drainage system and good drainage. Its main purpose is to prevent water from penetrating the foundation. Water that has saturated the ground can cause heaving of the soil and cracking of the foundation. Water can get inside the basement and cause the wooden house to rot from below.

The blind area can simply be made of asphalt, concrete or cement mortar (necessarily with reinforcement to prevent cracking, on a sand or gravel bed), it can be tiled, or it can be finished with the same material as the foundation itself. Its thinnest part should be at least 5–7 centimeters thick, and it must have a slope away from the house for better drainage of water.

The thinnest part of the blind area should be at least 5–7 centimeters thick, and it must have a slope away from the house for better water drainage

Sometimes the blind area is also insulated for better effect.

Insulating the foundation and blind area will completely protect the house from the cold

Photo gallery: options for blind areas and foundation linings

The foundation is faced with colored pebbles. Rubble stone and tiles are used here. Pebble cladding is a cheap, but very beautiful option. Cladding with rubble stone is very beautiful. The blind area and foundation can be finished with granite. Concrete blind area and stone-trimmed foundation - a competent approach. Concrete blind area and stone-trimmed foundation - very elegant solution Blind area finished with tiles on concrete Asphalt blind area is also an excellent and very simple solution Blind area trimmed with pebbles in concrete

Weather conditions during pouring

It is especially necessary to specify favorable weather conditions when pouring the foundation, since there are a lot of pitfalls when working in low temperatures.

1. Regular cement mortar will not set if the outside temperature is below 5 0 C, and your foundation will immediately begin to crumble.
2. Digging in frozen ground is always unpleasant. It's just very difficult to do it manually, and when using machinery there is a risk of damaging the equipment.
3. The sand and gravel cushion will be filled in poorly, because in winter both sand, pebbles, and crushed stone are in a frozen state, and it is extremely difficult to compact them well. When they thaw, the pillow will not have the required density and elasticity.
4. If you want to use waterproofing of the formwork, then the film is brittle in winter, and it will be extremely difficult to do it carefully.
5. The fittings have a high coefficient of thermal expansion. A reinforcement structure welded in the cold will certainly increase in size with warming.
6. In addition, there is always a danger that when the temperature rises and the ground thaws, the soil will move, and this will certainly lead to shifts in the foundation and can also lead to its rapid destruction.

Pouring a foundation in winter is a dangerous undertaking

But if you are itching and you are ready to work at low temperatures, or the nature of your soil (sand) is such that winter is the only way to avoid crumbling during excavation work, then you need to fulfill some conditions so that troubles do not arise later.

Table of concrete setting at different temperatures

The figure clearly shows that the optimal temperature for pouring the solution into the formwork will be in the range of 15–25 0 C.

Foundation calculation

Of course, we have already chosen a place for the house. The humorous picture determines all the permitted places for construction on your garden plot according to SNiP.

Drawing of choosing a location for a house, taking into account all the buildings and trees on the site and the neighbor’s fence

First, which is completely natural, we make a house project, relying on expert opinions or previously known data on soils and waters on the site. Choosing material for the house. We must not forget that a slab foundation occupies the entire area of ​​the house, and a strip foundation and all types of pile foundation grillages must be under every wall of the house, even the inner one. Taking into account all the factors, we chose a one-story wooden house made of rounded logs with an area of ​​122 m2.

A one-story wooden house is the best project for unreliable soils, and a strip foundation that is not very deep is well suited for it.

For the house we have chosen, a non-buried monolithic concrete strip foundation is perfect, which is most often used for light wooden and frame houses. Under such a foundation, trenches for water supply and sewerage can then be laid. It is a continuous monolithic tape, buried 50–70 centimeters and protruding above the ground by 50 centimeters, the same in cross-section in all its places. Its protruding part serves as a base.

Calculator

Do not forget that all external dimensions of the house and veranda are indicated in the center of the foundation strip, and not along its edges, and internal dimensions - according to the internal dimensions of the walls. If the number of internal walls indicated is insufficient for your project, their lengths can simply be summed up, which is what we did. The thickness of the foundation strip is set depending on our soil or our preferences.

Table: entering the necessary numbers in accordance with the house project

After entering all the initial data, the calculator gives us an accurate calculation of the materials we need and their cost, based on current average prices.

Table: final calculation of necessary materials and approximate calculation of finances

We will need tools:

• Bayonet and shovel shovels
• Wheelbarrow
• Manual rammer or vibratory rammer for compacting soil and sand
• Construction mixer for mixing cement (container for manual mixing)
• Welding machine for welding fittings
• Hammers
• Grinder for cutting reinforcement
• Nail puller
• Mount
• Hydraulic level or level
• Roulette
• Carpenter's meter
• Pliers
• Stitchers for finishing
• Circular saw for boards
• Electric drill for boards
• Board screwdriver
• Goats for cutting boards

Marking and excavation work

We prepare the site: mow the grass, level the ground, uproot trees and stumps at the construction site. The construction site should be larger than the area of ​​the house by at least a couple of meters in each direction.

We mark the trenches for the foundation strip with twine and pegs, not forgetting about the trenches for water supply and sewerage communications. The pegs must be driven in indented from the corners of the foundation so that the corners are marked by the intersection of the strings.

The height of the pegs should be equal to the base of the foundation - that is, the height to which the foundation strip protrudes above the ground.

Marking the foundation - parallel lines formed by strings are visible

The sand or pebble cushion under the strip foundation is compacted with a vibrating rammer

Video: creating a strip foundation with your own hands

You are convinced that pouring the foundation yourself is quite simple in technology, but complex in terms of time and labor costs. But you will save a lot of money and get satisfaction from the fact that you did it!

There are many types of foundations for the construction of private low-rise buildings. But most often, under domestic cottages, an option is installed in the form of a reinforced concrete strip under load-bearing walls. After all, to make a strip foundation with your own hands, you only need to have minimal skills in mixing concrete and follow the instructions. The technology for constructing such a base is simple, which is why it is so often chosen for independent implementation.

What it is?

Structurally, a strip foundation is a reinforced concrete structure created around the perimeter of the future structure to redistribute the load on the ground. A similar support is used for the construction of residential buildings, garages, outbuildings, bathhouses, garages and even fences. It's not difficult to make it yourself.

This is what he looks like

However, when building such a foundation, it is extremely important to adhere to certain rules and recommendations. If the strip foundation manufacturing technology is not followed, the durability of the supporting structure itself and the building on it can be forgotten. They won't last long.

Seasonal swelling of soil, exposure to moisture on concrete without waterproofing, incorrectly calculated loads - there are many reasons for the destruction of the strip foundation on which the house already stands. All of them must be foreseen and taken into account in advance, otherwise the damaged or completely destroyed structure will have to be rebuilt.

Types and types of foundation

According to its depth, it can be either MZLF (shallow) or simply recessed. In the first case, the concrete belt under a low-rise building is buried only 200–400 mm into the ground, and in the second, it is buried up to one and a half meters (below the freezing level of the ground).

If the soil at the construction site is rocky and the groundwater is deep, then it is better to choose a cheap and shallow concrete option that is small in volume. On heaving, high groundwater and sandy areas for the house you will have to make a more powerful and expensive support. Often the estimate for such a foundation for a home is such that it is necessary to choose a different type of foundation altogether.

Scheme of walls with MZLF

Structurally, a reinforced concrete strip base can be:

Monolithic;

The first type is performed by pouring a reinforced concrete belt. The second option is laid out from special factory-made foundation blocks (FBS) or bricks.

Pros and cons of strip foundations

It has three undoubted advantages

The device is extremely simple - any novice builder can handle pouring concrete and laying blocks (there are step-by-step instructions - to build everything correctly, you just need to follow it step by step);

The ability to withstand heavy loads both from below from the ground and from above from the weight of the cottage and everything in it.

A strip foundation made of reinforced concrete will last for many years, even if heavy solid bricks, rather than light aerated concrete blocks, are used to build the walls of the house. In terms of cost, it is second only to screw piles, but in most cases it surpasses them in reliability.

Among the disadvantages of such a foundation are:

Mandatory thorough soil analysis at the construction site;

The need to use lifting equipment (in case of using FBS);

Long concrete curing period of at least 3 weeks (if choosing a monolithic option);

Impossibility of laying on highly heaving and water-logged soils.

Step-by-step instructions - do-it-yourself foundation

The thickness and height of the tape of the base under consideration, as well as the depth of its placement, are selected based on soil analysis, climatic conditions of the area and the number of storeys of the building being built. Without knowledge in this area, it is better to entrust this design stage to a professional. There are many nuances and requirements of GOSTs that must be observed.

But it is quite possible to create a support for your house using a ready-made project yourself. But in order to avoid mistakes, it is best to make the strip foundation yourself with the step-by-step instructions given below. It describes all the intricacies of building such a structure for a typical one-story cottage.

Stages of work

The first stage is marking and excavation work. Regardless of the depth of the foundation, the sole must rest on solid layers of soil. It can be clay, sandy loam, rocky layers or loam. They are usually hidden under turf and layers of ordinary soil. All this will have to be torn down and removed before starting to build the foundation of the house.



We prepare the site, distribute the main materials: fittings, insulation, boards for formwork

To mark the area you will need pegs, tape measure and twine. If the soil is dense, then the walls of the dug trench will make excellent formwork. It will only be necessary to build it up from above. If the soil is loose and constantly crumbling, then the trench will have to be dug somewhat wider so that formwork boards can be placed inside the hole.

The second stage is preparing the pillow. The bottom of the dug trench is leveled with sand and fine gravel. This sand and gravel layer should be thoroughly compacted, pouring water as it is poured. It should be between 10–30 cm in height. This cushion serves to redistribute and reduce point loads on the strip foundation from below during seasonal heaving of the soil.



You can put insulation on top of the pillow - this will prevent heaving from freezing the ground

The third stage is placing the formwork. Here you will need bars with a cross section of 30 to 40 mm and boards with a thickness of 15–20 mm or laminated chipboard. The formwork created for the concrete foundation of a house will subsequently be required to withstand a considerable mass of concrete poured into it. It should be made strong and reliable. If, after filling with the concrete mixture, it collapses, then everything will have to start again.



We install formwork from boards

If the groundwater at a construction site is high, then reinforced concrete will require waterproofing. From above, at the level of the base of the house, it is usually done as a coating. And to protect that part of the base that remains in the ground, roofing material should be laid in the trench on the sides and on the bottom. It will reliably protect concrete from excess moisture in the soil at the stage of its hardening and after.

The fourth stage is laying the reinforcement. For reinforcement, steel rods with a cross-section of 14–16 mm and thin dressing wire are usually used. The reinforcement can also be fastened using electric welding. But in this case, you need experience working with a welding machine and yourself. Plus, when performing welding, you must be prepared for the occurrence of metal corrosion in the future.



We knit reinforcement






Inside the trench, a frame of reinforcement with cells of 25–30 cm should eventually be formed. Moreover, it is laid so that the steel is covered on all sides by the poured concrete. Otherwise, the metal will inevitably begin to rust, and the house will definitely not last long.








The fifth stage is pouring concrete or laying out FBS. If it is decided to equip the foundation for a house being built using block technology, then this greatly speeds up the process of its construction. Here you don’t have to make formwork and wait almost a month for the concrete to set.

However, support on foundation blocks will cost more than a monolithic counterpart. Plus, they will have to dig a larger trench in width. To distribute the loads for the bottom row, FBS masonry is made with an expanding base.

If a monolithic option is chosen for the support structure, concrete should be poured immediately over the entire surface. No breaks in length and no layers in height. A monolith is just a monolith. The house must stand on a reliable foundation.



Nails can be used to mark the pouring boundary in the formwork.

When preparing the concrete mixture yourself, you need to mix cement, sand and crushed stone in proportions 1: 3: 3. But it is better to initially order a ready-made solution with a grade of M300 or higher.



Fill in











When pouring concrete, it is extremely important to ensure that no voids form inside it. There are special vibrating machines to perform compaction. However, you can also use a piece of reinforcement to pierce the poured mass and release air from it.








The sixth stage is waterproofing and blind area. It is allowed to begin waterproofing work 3-4 days after pouring concrete. It takes about three weeks for it to fully set. But you can already begin treating the strip foundation for the house with mastic, even though it has not yet completely hardened.



Waiting for it to harden

Also, along the entire perimeter of the building, you will need to make a blind area to drain rainwater away from its walls.



Ready foundation with basement rows of bricks

Use for building a house

Such a support can easily support private houses two to three floors high. To build a cottage on it, you can choose laminated veneer lumber, logs, foam blocks or ceramic blocks. You just need to properly examine the soil and correctly calculate all the loads. Finally, it wouldn’t hurt to cover the foundation for additional protection from the weather. Natural stone or clinker tiles for the facade are ideal for this. But you can choose easier-to-install and inexpensive corrugated sheeting or siding.

Many private developers are constantly faced with the need to build the foundation of a country house for themselves, their friend or neighbor in the countryside. Moreover, this can be a private residential building or a commercial structure, so for each specific house the foundation structure can differ significantly.

Many existing foundations can be built by yourself in a matter of days or weeks, and if everything is done correctly, then the reliability of such a foundation is practically no different from one that was built using powerful construction equipment and teams of qualified builders.

What factors does the choice of foundation depend on?

To build a foundation for a country house, it is necessary to correctly determine the type, characteristics and purpose of the future structure, as well as adhere to the step-by-step methodology for constructing the load-bearing structures of the structure. Factors influencing the choice of foundation:

1. Soil type and load-bearing characteristics. It is worth taking into account the height of the groundwater, seasonal heaving of the soil, the load-bearing characteristics of the soil, as well as the terrain. It is clear that on a strong slope no one will build a monolithic foundation or prefabricated structures made of aerated concrete, because then a huge amount of work will have to be done to level the site. But a columnar base with a grillage is ideal for such purposes.
2. The mass of the future building and its overall dimensions. As a rule, country houses are rarely multi-story; they are built one-story, less often two-story. Relatively lightweight aerated concrete or heavier bricks are used as building materials; concrete blocks are not used here. Therefore, a private house is distinguished by its lightness and low permissible load on the ground, and it is advisable to select the type of foundation after calculations.
3. Financial component. Every builder of a private house understands perfectly well that the financial component plays an important role in the construction of the foundation. It is clear that they all want to choose the right structure for a private one-story house, but they also immediately calculate all the permissible risks and the cost of building materials. Therefore, if there is aerated concrete production nearby or deposits of natural building stone are discovered, they will use it and the foundation structure will be appropriate. In addition, the foundation for a house is often built with one’s own hands without the use of additional labor and powerful construction equipment, as this will significantly increase the cost of the financial estimate.
4. Purpose of the future building. If this is a one-story or more private residential building, then the foundation is selected as strong and reliable as possible. But if this is a small outbuilding, then the type of foundation will be completely different.

You also need to remember that step-by-step instructions for laying a foundation differ significantly under different climatic conditions and the characteristics of a particular area, so it would be more correct to first decide and then build. An important role is played by the choice of building materials, from what exactly the future foundation for a country house will be built.

Types of foundations for a country house

Tape. It is easy and quick to build such a foundation for a country house, and often you can use aerated concrete or brick.

It is used in the construction of heavy one-story or more buildings, the load-bearing walls and ceilings of which will be built from heavy materials. This type of foundation is popular in suburban construction due to the ability to equip underground premises (garage, basement or technical floor).

Of course, there are several types of such bases that differ in design:

• Prefabricated. The device involves the use of ready-made factory reinforced concrete blocks, which are mounted directly on the construction site.
• Monolithic. By design, they have a single monolithic slab, load-bearing walls are erected on it. Such a slab is made from brick or rubble concrete, less often from aerated concrete. Reinforcing mesh can also be used here; such foundations are already called reinforced concrete.
• Pile foundations for weak soils. The device involves the installation of ready-made metal or reinforced concrete piles (pillars) at the construction site. They can be of considerable length, since it is necessary to reach strong layers of soil below the freezing line.

Also, such foundations are popular because of their practicality and reliability, although it will not be possible to build even a one-story, but large private building on stilts.

Piles can be different, ranging from metal and reinforced concrete to wood. The weaker the material, the less load they can withstand. Therefore, for the construction of a large private country building, it is better to immediately use reinforced concrete structures, which can be made directly on the construction site.

Just first you need to carry out the correct calculations and lay the foundation under optimal temperature conditions. It is also worth initially deciding what the foundation will be built from and creating a step-by-step methodology for its construction.

• Universal monolithic slab. The construction of such a foundation allows the construction of private houses even on soft soils, because then the load is distributed evenly over the entire area of ​​the base.

But the foundation is expensive due to the large amount of concrete and reinforcement, and building it with weak materials at hand is prohibited by building codes. It is better to lay such a foundation for small country houses, because then there will be a minimum of financial expenses for land work, and the foundation can be shallow.

Main stages of laying the foundation

As a rule, laying the foundation always begins with preparing the construction site. But in practice, everything turns out a little differently, because it is impossible to choose and build the foundation correctly without preliminary calculations. Therefore, there are several key preparatory steps that need to be done before building the foundation for a house yourself:

1. First, a detailed geodetic exploration of the territory is carried out, a soil map is drawn up and the depth of groundwater is specified.
2. Then a map of the soil structure is developed and the depth of solid rocks and the limiting depth of soil freezing are determined.
3. The location where it is best to build the designed private building is determined.
4. The angle of inclination of the terrain is determined, and minor unevenness of the construction site is eliminated.
5. A calculation is made of the maximum permissible load on the foundation, taking into account building materials. Sometimes in such calculations, aerated concrete is taken as the initial parameters, which is larger in mass than brick, but smaller than concrete structures.
6. The optimal type of foundation is selected.
7. The type of building materials that are best suited for the construction of the designed structure is selected.

Step-by-step instructions for laying a strip foundation for a one-story country house

How to make a foundation for a house with your own hands? In practice, it is not as difficult as it seems, but still, consulting an experienced builder will not be superfluous, since the knowledge gained will help to avoid mistakes. Laying any foundation consists of the following steps using the example of a strip structure:

1. The construction site is marked, the surface is leveled and the loose layer of fertile soil is removed.
2. Then a trench of the estimated depth and width is dug along the perimeter of the future building, the bottom is leveled and a sand cushion is formed on it.
3. Along the perimeter of the future foundation, wooden formwork is installed, inside of which a reinforcing belt is provided. The design, structure and characteristics of the reinforcement are selected individually for a specific type of foundation.
4. After installing the reinforcement and connecting it, the actual filling of the trench with concrete begins. This must be done evenly; separation should not be allowed. In this case, it is possible to use prefabricated structures made of concrete or aerated concrete, only then the reinforcement must be done both horizontal and vertical with longitudinal inserts.

A layer of waterproofing is installed on the outer surface of the finished base, then you can further strengthen the structure with a vertical row of aerated concrete or brick.

How to properly build a columnar or pile foundation with your own hands

Considering that a columnar or pile foundation is more commonly used for the construction of small private buildings for economic purposes, the financial costs of its construction are minimal.

To do this, you first need to mark the territory, set marks for future posts and drill holes to a given depth. Then sand and gravel are poured onto the bottom of the well, compacted and a vertical reinforcement belt is installed.

After all the preparatory work, the wells are filled with concrete and left to dry for several weeks. Instead of concrete, you can use aerated concrete, only in such cases it is necessary to initially provide good waterproofing of rectangular pillars.