Strip foundations are the most common, but not applicable on all soils. To begin the construction of such a foundation, it is necessary to carefully examine the soils and decide how thick and how high the tape should be.
In this article, we will describe in detail all the stages of the construction of a strip foundation, starting from digging a trench, reinforcing, formwork and ending with pouring concrete.
Geology of the soil under the foundation
This is the most important stage by which the following data are determined:
- Soil type and its design resistance.
- Freezing depth.
- Ground water level.
- The degree of heaving of the soil and its uniformity.
After geology, you can proceed to the design of the foundation itself.
Depending on the architectural solution, that is, the initially planned building, the weight of the house is determined, including the weight of the foundation, snow, wind and payload. The type of foundation, in our case, tape, can be buried and shallow.
The next step is to determine the parameters of the foundation itself, namely:
- Foundation width.
- The height of the recessed part.
- Above ground height.
- Is drainage required?
To determine the width of the foundation, it is necessary to divide the weight of the house by the area of \u200b\u200bthe foundation support, and the resulting value should be less than the calculated soil resistance by 20%.
To increase the area of the foundation support, a broadening (heel) is made, which distributes the load over a larger area.
We wrote about this in more detail in our previous article - how to calculate the weight of the house.
For a deep foundation, the laying depth should be 20 cm below the freezing depth. For a shallow foundation, it all depends on the soil, or rather on heaving, freezing depth and groundwater level.
For an approximate determination of the depth of a shallow foundation, see the table.
- The maximum height of the above-ground part of the strip foundation should not exceed four widths of the foundation strip.
- The above-ground part should be smaller than the underground part.
- The optimal height of the aerial part is 40-50 cm.
Performing site markings
According to the finished project, it is necessary to carefully measure all the corners of the future foundation and set the pegs. The stakes are placed along the outer and inner perimeter of the foundation, a cord is stretched between the stakes, defining the contours for digging the foundation trench.
At this stage, a trench is being dug, the depth of which should be under the foundation project, taking into account the sand cushion and formwork. There are two ways to dig a trench: with a tractor using a narrow bucket, and manually (with shovels). The tractor will cope much faster, but with shovels it turns out smoother and more accurate.
The sand cushion is made about 20 cm thick, wetted with water and well compacted.
In some cases, it will be much more convenient to first tie the frame in the trench, and only then expose the wooden formwork.
Frame reinforcement steps:
- Stones or bricks 5-6 cm high are laid at the bottom of the trench, the task of which is to raise the reinforcing cage in order to create a protective layer of concrete from below.
- Further, longitudinal reinforcements are laid out on the bottom, not rods, previously bent at the corners.
- Next, pre-made clamps are put on the bottom row of reinforcement, they are also frames, they are also transverse reinforcement.
- Clamps and a row of lower reinforcement are connected with knitting wire.
- If the height of the tape is more than 80 cm, then structural rows of reinforcement are added, one row or more.
- Further, the upper longitudinal reinforcement bars, L-shaped clamps at the corners are added to the frame and are connected with wire.
- To provide a protective layer of concrete on the sides of the foundation, special plastic rings are used to help hold the frame in position.
We highly recommend that you familiarize yourself with our article about the calculation of the reinforcement of a strip foundation, which describes in detail all the nuances for the selection of reinforcement and the scheme for reinforcing corners.
The formwork is knocked down from wooden boards, and reinforced with many bars, which additionally rest against the ground on pegs. Also, to strengthen the formwork, metal wire ties are used, or studs are tightened in plastic tubes.
The installation of the formwork must be approached very responsibly, since liquid concrete has a large bursting force, especially if the height and width of the formwork are large. Quite often, formwork bursts for inexperienced builders, and concrete flows to the ground. To avoid this situation, reinforce the formwork as much as possible. And remember that more concrete pressure is created at the bottom.
Do not forget about the installation of sleeves for communications (water, sewerage).
It is very important that the foundation be monolithic, and in order to achieve this state, it is necessary to pour concrete into the trench in one go. Manually, with a concrete mixer, this is unlikely to be achieved, therefore it is better to order the delivery of ready-made concrete in mixers.
- The time between delivery of concrete trucks should not exceed two hours.
- Pouring is best done in layers, pulling the concrete around the entire perimeter.
- For a more plastic (liquid) concrete mix, ask to add a plasticizer to the mixer.
- Excess water in concrete reduces grade strength, increases the number of shrinkage cracks and increases the number of pores in concrete, making it less moisture resistant. Avoid excess water during the kneading process.
- During pouring, you need to use a deep vibrator, which compacts the concrete and expels air.
- Try to level the plane of the foundation tape as much as possible.
- During the week, it is necessary to shed the surface of the foundation with water, this will avoid shrinkage cracks and help the concrete gain brand strength. We also recommend covering the tape with foil.
The foundation is ready. It remains to perform vertical and horizontal waterproofing, as well as an insulated blind area, which reduces the depth of freezing and removes excess water from the foundation.
About how long the foundation should stand, we wrote a separate article, which discusses options for settling from 10 days to six months.
The construction of buildings begins with a load-bearing foundation, which determines not only the service life of the building itself, but also forms the comfort and microclimate inside the premises. The strip foundation is one of the most popular types of foundations used both for the construction of private housing and for the construction of technical buildings.
Features of the strip foundation
A strip foundation is a load-bearing base, which is a closed loop in the form of a strip of reinforced concrete, bricks and block building materials. The tape is erected under the bearing walls of the building, which contributes to the uniform distribution of the load and its further transfer to the underlying soil layers.
For the manufacture of a monolithic strip foundation, high-strength concrete grades are used
The design of the strip foundation allows you to build structures both from wood and foam concrete, and from brick and concrete blocks. When building a foundation, a large amount of land and construction work is required. Despite this, the strip foundation is popular both among summer residents and owners of suburban areas, and among professionals.
The arrangement of the foundation is carried out on a pre-compacted pillow of sand and gravel. After hardening, the carrier tape is covered with an insulating material that will protect the integrity of the reinforced concrete surface. If the total weight of the building being erected is small (up to 50 tons), then the preparation of the underlying cushion can be neglected.
The configuration of the carrier tape depends on the shape of the walls of the building under construction
The competitive advantages of the strip foundation include:
- technology proven and refined over the years. A properly executed base will evenly distribute the load exerted on it without the risk of collapse of the supporting structures of the building;
- strength. The monolithic construction of the foundation ensures high reliability and durability. Subject to technology, the service life of the foundation can reach 100 years or more;
- versatility. The strip foundation can be used both for heaving and moving soil types, and for loamy and clay soil types. To improve performance, it can be combined with vertical piles and supports.
The disadvantages include the fact that the construction of a strip foundation is a very time-consuming process, requiring the investment of a considerable amount of finance. On average, the cost of a supporting foundation is 15-20% of the total budget allocated for the construction of a house.
The foundation construction technology assumes that the tape will be poured in a work shift, and it is problematic to prepare such a volume of concrete mix even with a concrete mixer. Because of this, it becomes necessary to purchase concrete from the manufacturer, which is also a significant waste.
Types of strip foundation according to the depth of laying
According to SNiP 3.02.01-87 "Earth structures, foundations and foundations", tape bearing foundations are classified according to two criteria:
- by depth;
- according to the method of the device.
The depth of the foundation depends on the bearing capacity of the soil and the calculated load that will be placed on the foundation being built. The bearing capacity of the soil is determined based on its type, the depth of freezing and the presence of groundwater in the area where the building is planned to be built. Read about the design and method of strip foundation construction in the next section.
Shallow strip foundation
A shallow strip foundation is a strip of concrete and a reinforcing frame, located at a shallow depth in the ground. The minimum level of laying depends on the depth of soil freezing, its heaving and the height of groundwater.
A shallow strip foundation can be made of reinforced concrete, brick or foam blocks
For example, if the groundwater is high and the depth of soil freezing is large, then both lateral and tangential heaving forces will act on the foundation, which will compress and displace the shallow carrier tape. And vice versa - the lower the groundwater level and the higher the level of soil freezing, the less the impact of heaving forces.
The recommended minimum depth of the strip foundation can be found in SNiP II–B.1–62. For reference, we offer a table compiled on the basis of data from this document. On average in Russia, the depth of laying varies from 0.4 to 0.75 m. Additionally, you can consider the depth of seasonal freezing of the soil in the region where it is planned to lay the bearing foundation.
Table: foundation depth depending on the level of soil freezing
The depth of laying a shallow strip foundation in the central region of Russia should not be less than 0.5 m
The construction of shallow strip foundations is recommended in the following cases:
- in regions with high average annual temperature and shallow depth of soil freezing;
- in the construction of private houses using frame technology, as well as buildings made of aerated concrete, foam concrete and other materials with low weight;
- when warming the supporting base from the outside, coupled with the arrangement of a blind area made of crushed stone, sand and concrete.
The construction of a shallow strip foundation on soil consisting of peat, sapropel, silt and other organic deposits is strictly prohibited. It is not recommended to build this type of strip base on mixed and heaving types of soil that are oversaturated with moisture.
Buried strip foundation
A buried foundation or a deep foundation is a load-bearing reinforced concrete or prefabricated strip, which is 20–30 cm lower than the level of soil freezing.
The depth of the carrier tape can reach 1.5–2 m, depending on the level of soil freezing
The main idea behind the deep laying of the carrier tape is to rely on dense soil layers with a higher bearing capacity. This type of foundation implies even greater volumes of excavation and concrete mix costs.
The construction of a deep strip foundation is recommended:
- in regions with low temperatures in winter and freezing of the soil to a great depth;
- if it is planned to build a two- or three-story house made of bricks, reinforced concrete blocks and slabs;
- in the presence of fine-grained soil types supersaturated with moisture.
In addition, the recessed foundation allows you to equip the basement. With high-quality insulation and sufficient insulation, it is possible to equip a basement floor intended for living or storing things.
Types of strip foundation according to the device method
Depending on the design features, strip foundations are monolithic and prefabricated. They, in turn, can be divided into monolithic foundations with vertical supports and precast tapes made of brick or foam block.
Monolithic strip foundation
When constructing a monolithic strip base, reinforcement and pouring of the foundation are carried out directly at the construction site. As a result, the overall integrity and continuity of the carrier tape is achieved.
A monolithic strip foundation is an inextricable reinforced concrete strip around the entire perimeter of the building
Depending on the geology of the site, the depth of laying a monolithic foundation varies from 80 to 250 cm. When building private houses, the laying depth rarely exceeds 150 cm.
Monolithic types of foundations, regardless of technology, are used to build objects for various purposes on heaving and moving types of soil. Monolithic design provides high strength and reliability of the bearing base.
Pile and column-strip foundation
Pile-tape and column-tape types of foundations are a monolithic reinforced concrete strip located on supports buried in the ground. In fact, these types of foundations - nothing more than a modernized version of pile or columnar foundations with a grillage.
Pillars or piles are located along the perimeter of the foundation with a step of 2 m
In the first case, steel products in the form of piles of various lengths are used as supports, which are screwed into the ground manually or automatically. In the second, the supports are made from the same concrete mixture that is used to fill the carrier tape.
The arrangement of pile and columnar foundations of the tape type is justified only in the construction of facilities in areas with a large depth of soil freezing. Steel piles or reinforced concrete poles buried below the freezing level of the soil will distribute the load that is transferred from the reinforced concrete strip.
Prefabricated strip foundation
The main material for the construction of a prefabricated strip foundation are reinforced concrete foundation blocks (FBS), made of heavy grades of concrete. The foundation carrier tape is formed from the blocks, which is located along the perimeter and area of \u200b\u200bthe future building. To connect the blocks to each other, concrete grade M350 and steel reinforcement Ø15 mm are used.
After assembling the foundation, the outer surface of the bearing base is treated with waterproofing materials. The most commonly used bituminous mastic and special bituminous membranes, which have a self-adhesive base.
Prefabricated strip foundation consists of reinforced concrete foundation blocks connected with concrete
The main advantage of the prefabricated strip foundation is the short construction time. Unlike a monolithic base, you do not have to wait for the minimum strength of the concrete mixture to set. You can start building a house within a few days from the moment the tape is assembled.
Despite this advantage, a prefabricated strip foundation is used for the construction of private houses a little less often than a monolithic concrete foundation. This is largely due to the fact that the prefabricated structure is not suitable for use on moving types of soil. With the same thickness, the strength indicators of a prefabricated structure are 20–30% lower than a monolithic one.
Brick strip foundations are a prefabricated structure and are often used for the construction of one-story houses using frame technology. For the manufacture of the tape, burnt solid brick is used. Depth of laying - 40–50 cm.
The strip foundation made of bricks is highly maintainable, but requires the arrangement of high-quality waterproofing
After assembly, as in the case of blocks, it is necessary to equip a full-fledged waterproofing layer. The benefits of this foundation include:
- structural rigidity;
- high maintainability;
- ease of arrangement.
If we make a more detailed comparison of bricks with reinforced concrete blocks, then the foundations of the blocks are less hygroscopic and higher strength. The brick is more fragile, which affects not only the frequency of repairs, but also the life of the structure as a whole. With this in mind, it is recommended to build a brick strip foundation in areas with dry and hard soil, as well as with low groundwater.
How to make a strip foundation for a house
In order to start the construction of a strip foundation, it will be necessary to perform calculation operations, during which it is necessary to find out the depth of the foundation and the width of the carrier tape. If possible, these works can be delegated and contacted by a design and construction organization, where all the necessary parameters will be calculated for you, on the basis of which a project for the future foundation will be drawn up.
Calculation of the strip foundation
If you decide to survey the soil and draw up a project yourself, then be prepared that even a small mistake made can lead to the destruction of the house. Especially if you are planning to build a two- or three-story building.
Table: the depth of the strip foundation, depending on the type of soil
| Type of building | Depth of the strip foundation (cm) depending on the type of soil | ||||||
| Rocky ground, flask | Dense clay, soft loam | Packed dry sand, sandy loam | Soft sand, muddy ground | Very soft sand, sandy loam, silt | peat bog | ||
| Barn, bathhouse, household the buildings | 20 | 20 | 30 | 40 | 45 | 65 | |
| One-story cottage with an attic | 30 | 30 | 35 | 60 | 65 | 85 | Requires a different type of foundation |
| Two-storey cottage | 50 | 50 | 60 | Requires calculation of specialists | Requires calculation of specialists | Requires a different type of foundation | |
| Multi-storey cottage | 70 | 65 | 85 | Requires calculation of specialists | Requires calculation of specialists | Requires calculation of specialists | Requires a different type of foundation |
For low-rise buildings made of wood, garages, bathhouses, chicken coops and technical buildings, you can perform a calculation taking into account the recommendations given in SNiP II–B.1–62 “Foundations of buildings and structures”.
The simplest option is to check the known parameters with a special table that allows you to determine the depth of the strip base. The referenced table is shown above. For reference: 1 kN = 101.9 kg. The table has been compiled on the basis of European standards adopted in 2010.
To level the site, improvised means, hand tools and special equipment are used.
As an example, we will calculate the parameters of the strip foundation required for the construction of a one-story dacha made of timber, the length of which is 8 m and the width is 6 m. The height of the dacha, not including the roof, is 2.5 m. The building will be built on the ground of dry fine sand. The depth of soil freezing is 1.4 m, which corresponds to the central part of Russia.
The sequence for calculating the strip foundation is as follows:
- Building weight - to calculate the total weight of a building, you must have a building design that describes what materials will be used to build it. On average, the weight of a one-story structure made of timber with an attic is no more than 70 tons. To this value should be added the weight of heat-insulating materials, ceilings and partitions, as well as snow load (160–240 kg / m 2). As a result, it turns out that on average a one-story dacha with the parameters announced above will weigh about 100 tons.
- Foundation area - length of the carrier tape: (6 + 8) * 2 + 6 = 34 m. The width of the tape is selected depending on the weight, but not less than 20 cm. As a result, it turns out that the surface area of \u200b\u200bthe foundation is: 28 * 0.2 m \u003d 6.8 m 2. This value may be adjusted later.
- Depth of laying - the soil consists of dry sand, the freezing depth of which is 1.4 m. From this we can conclude that the soil in the area is non-porous. Therefore, for the construction of a one-story cottage, you can use a shallow foundation with a laying depth of 0.6 m.
- The load on the carrier tape - according to SNiP 2.02.01-83 "Foundations of buildings and structures", the formula is used to calculate the load: P = total weight of the structure / foundation area. For fine sandy soil, the resulting value should be less than 20 tons (value taken from DBN V.2.1-10-2009). In our case, P \u003d 100 / 6.8 \u003d 14.7 t / m 2.
Based on this, we can conclude that the previously indicated width of the carrier tape (0.2 m) is ideal for a one-story cottage weighing no more than 100 tons. As a result, it turns out that for the construction of a timber cottage with an area of 48 m 2, a strip foundation 0.2 m wide is required, which will be buried in the ground by 0.6 m.
Using the tables given in this article and SNiP 2.02.01–83, you can perform a calculation for any strip base that will be built on non-rocky soil types. Data on the weight of building materials can be taken from open sources, and for an approximate calculation, use online calculators.
Site preparation
After all the design operations have been completed, the project of the foundation and the future building has been received, you can proceed to the preparation of the land. During preparation, it is necessary to clean and mark the surface of the site using improvised means.
The marking of the site for the strip foundation is carried out using wooden pegs and a strong rope that is stretched between them.
To prepare, you will need to do the following:
For the final check, it is necessary to measure the diagonals of the site under the foundation. To do this, the thread is stretched crosswise. If everything is done correctly, then the diagonals will be equal. Otherwise, it is necessary to double-check the corners with the device and rearrange the pegs.
trench digging
During earthworks, it will be necessary to dig trenches to the design depth, which is calculated taking into account the type of soil and the foundation being built. To do this, you can use both special equipment and hand tools in the form of shovels and scrap.
The trench for the strip foundation is dug to the design depth of the bearing base and the underlying cushion
To equip trenches around the perimeter of the foundation, you will need to perform the following activities:
Formwork device
For the manufacture of formwork, an edged board 20 × 150, 20 × 175 or 20 × 299 mm is used, which is fastened with wooden bars 50 × 50 mm. If possible, you can use moisture-resistant plywood, which is mounted on a pre-assembled frame from a bar. The principle of the arrangement of formwork panels is shown in the photo below.
The formwork is installed in the following sequence:
If the foundation provides for the laying of pipes for communications and the creation of ventilation gaps, then special holes of the desired section are sawn in the formwork. For this, an electric drill with a crown nozzle is used.
Video: formwork installation
Reinforcing frame installation
To reinforce the strip foundation, a frame made of steel reinforcement Ø12–15 mm is used. The frame is assembled by welding or using steel wire.
The knitting of the reinforcing frame is as follows:
When knitting, it should be remembered that the frame must be hidden under a layer of concrete to a depth of 5–6 cm. The maximum length of the jumper with a tape width of 40 cm should not exceed 30 cm.
To speed up the knitting process, you can purchase a special construction gun that works on the principle of a stapler, but instead of the usual staples, it uses steel wire of the desired section.
Video: how to knit a reinforcing cage
Pouring concrete mixture
When erecting strip foundations for private housing, a concrete mix of the M200, M250, M300 or M350 brand is used. Concrete brand M200, as a rule, is used only for small frame baths and utility rooms. Concrete of higher grades - for pouring foundations for the construction of two- and three-story houses, and concrete M350 - only for overall buildings.
The foundation is poured strictly in one step, so it is important to ensure the required volume of concrete mix, which is calculated based on the size of the foundation. If it is not possible to prepare the required amount of concrete, then the foundation is poured in layers with the obligatory tamping of each layer.
The proportions of the solution for independent mixing of the mixture are 1 part of cement, 2 parts of sifted sand and 4 parts of crushed stone of fraction 20–40. When changing the proportions of the solution, it should be remembered that there should be 1.5–2 times more crushed stone than sand.
Automated supply of concrete mix will greatly speed up the process of pouring the strip base
You can start pouring the mixture from any convenient place in the trench. Concrete is fed in portions so that it can be evenly distributed over the volume of the trench. To compact the mixture, a reinforcement rod or a wooden lath is used.
The last portion of concrete is leveled along a stretched guideline. To do this, raw concrete is covered with dry cement and rubbed with a wooden grater. After that, the foundation is covered with a plastic film and moistened 2-3 times a day with a small amount of water.
The concrete strip foundation will gain full strength no earlier than after 27 days, but after 14-17 days it is already possible to dismantle the formwork. After 27–30 days, the foundation is waterproofed and backfilled.
Despite the relatively high cost, the strip foundation is one of the most durable types of load-bearing bases. In addition, many owners of suburban areas prefer this type of foundation, as it allows you to equip a basement or even an entire basement.
The concept of "strip foundation" characterizes only its form. In practice, for low-rise buildings, there are several options for manufacturing a base of this shape. We will briefly talk about some and give instructions for the step-by-step construction of a monolithic foundation.
Tape depth options
There are two types of tape in depth. If the sole is no deeper than 60 cm, then this is a shallow foundation.
This also includes bases when the sole is on the surface of the ground. And to be more precise, a little lower, given that the site is leveled. In practice, such a foundation in its pure form is placed where there is no fertile layer. Such conditions are rare. In most cases, there is a humus layer on the construction site, so the scheme for arranging an unburied foundation looks like this:
- completely cut off the fertile layer along the entire base of the future structure;
- a layer of sand is covered (if necessary, improve the bearing capacity of the soil - also crushed stone);
- water, level and tamp the pillow;
- put the formwork for the tape.
- Concrete floors on the ground, raised to the height of the basement.
- Basement with underground and floors on the floor.
But the foundation deepened into the ground up to 60 cm is more common.
All these options are common in private construction, when the project does not provide for a basement. It has been proven that the heaving forces at a shallow depth are compensated by the weight of a low-rise building, and the bearing capacity of a shallow-depth tape is sufficient to withstand the load.
The sole of the buried lies in the ground below the freezing point.
This type is the most durable, but it is also the most material-intensive. It is laid when a basement or an underground technical floor is needed to accommodate engineering systems equipment.
Classification by technology
According to the manufacturing method, there are three types of base tape: prefabricated, monolithic, combined. And already these technologies have their subspecies.
The prefabricated base is assembled, as a rule, from concrete blocks (FBS).
They also use a more “small format”: ceramic brick or cinder block. But even for a foundation of solid building blocks, the bearing capacity is weakened by the seams - and even the reinforcing belts cannot fully compensate for this. Therefore, in its pure form, a brick or cinder block foundation is rare, and building blocks go to the base of combined foundations.
If for FBS a solution is needed to fill the irregularities of the spoon and there are no special requirements for the brand (the adhesion strength of the blocks is provided by weight), then when using “small forms”, a full-fledged masonry mortar is required. In addition to the FBS assembly, medium-sized natural stone foundations are also popular.
And the popularity is explained simply - high decorative properties.
Combined foundations can also have different technological schemes. For example, an underground part made of reinforced concrete plus a brick base.
There are two types of monolithic tape: with rubble stone, poured with concrete, and from reinforced concrete.
In the first version, the reinforcing role is assigned to a small rubble stone. Unlike a “clean” rubble foundation, rubble concrete provides for: installation of formwork, laying a pillow, pouring a small layer of concrete, laying the first row of stone into it, pouring a mortar layer, laying the second row, etc. The distance between the stones is about 5 cm, and the ratio of the volumes of mortar and stone is approximately 1:1.
The attractiveness of this type of foundation is in reducing the volume of concreting, and, consequently, the cost of materials.
But the most reliable is a monolithic concrete tape with a reinforcing frame.
Monolithic strip foundation
Manufacturing technology has the following sequence.
On the ground, a pit is marked (for a deep foundation) or a trench system (for a shallow foundation). Carry out excavation work.
If the tape is shallow and communications enter / exit under the sole, then they dig a trench for them and lay sleeves for laying pipes under the tape. Align (plan) the bottom of the pit or trenches. They fall asleep, level, moisten and ram the sand and gravel cushion. The total thickness of the pillow is up to 30 cm (the ratio and volume of the parts depend on the characteristics of the soil), and the width of the pillow is 30 cm wider than the heel of the foundation. Install the formwork.
The materials are edged board and timber. It is allowed to use an edged board with a wane, but so that there are no gaps between them.
To simplify the assembly procedure, it is possible to make shields from boards and timber on the ground. The wall thickness of the formwork must withstand the pressure of the concrete. The strength of the formwork is increased by connecting the racks along the horizon with steel wire and reinforcing the side stops on the ground on one or both sides.
For a deep foundation, when constructing a basement, it is recommended to install a non-removable foam formwork.
At the formwork of the buried foundation, holes are cut out for sleeves for engineering communications. For sleeves, pieces of plastic or asbestos-concrete pipes are used. The diameter of the sleeve is chosen based on the dimensions of the passing pipes and the insulation layer. At the time of work on the arrangement of the foundation, the sleeves are filled with sand and the holes are closed.
Install reinforcing frame. The diameter of the reinforcement, the mesh parameters depend on the design indicators of the bearing properties. The main purpose of the "iron" is to improve the resistance of the foundation to fracture and to lateral loads, the compressive strength of the concrete stone is already high. The distance between the reinforcement and the walls of the formwork is at least 50 mm.
The concrete is poured in layers. If there are access roads, and a concrete plant is nearby, then it is better to use a ready-mix.
Otherwise, the mixture is prepared by themselves, observing the proportions to obtain the required grade.
The optimal layer thickness is up to 20 cm. And the filling of the layer should be continuous around the entire perimeter. Each layer is compacted in one of the ways: with a deep vibrator or bayoneted with a piece of reinforcement (for small volumes).
After pouring the last layer, it is covered with a plastic film (this is a necessary condition for the normal hydration of concrete). It is allowed to cover the basement of the foundation with burlap and periodically moisten it. The first seven days are critical, when the concrete stone gains 70% of the design strength.
Four weeks later, the formwork is removed. Then carry out waterproofing. The choice of materials and technology depends on the nature of the soil and the level of groundwater. Roll materials are popular, which are deposited on a prepared surface.
When building a house or other buildings, strip foundations are most often preferred, since such a foundation has many advantages. The strip foundation for the house is quite simple in device and, if necessary, it can be poured without the involvement of construction equipment. Such a foundation is a universal design and is used in the construction of light wooden and heavy stone buildings on various types of soils. In more detail, what is a strip foundation, its types, and how it is equipped, we will consider in our article.
Strip foundation in section Source bayanay.info
Types of strip foundation
Before proceeding with the construction of such a foundation, it is necessary to carefully consider its features and varieties. This will allow you to choose the right foundation for the construction of a particular structure. It will also make it possible to properly carry out all the necessary work. A strip foundation is not just one way to make a foundation for a house, there are several types of them:
1. One piece
A monolithic or solid strip foundation is being built directly at the construction site. To begin with, a formwork is being constructed, into which a reinforced belt is laid along the entire length. After that, concrete is poured.
The base is a closed monolithic contour made of reinforced concrete. Thanks to this, it is possible to create a solid frame that is suitable for any soil, including unstable ones. On this basis, you can easily build a country house or a stone fence.
Among the advantages of this design are ease of construction and reliability. In this case, the base can have a different shape. As for the shortcomings, there is a large mass of a monolithic structure.
Solid cast strip foundation - concrete is poured in one step into the prepared formwork Source sazhaemvsadu.ru
2. Prefabricated
For the construction of the foundation, ready-made reinforced concrete blocks are used. Of these, a tape of the desired shape is laid out directly on the site. They are fastened with cement mortar. They are optimally suited for the construction of low-rise buildings. Buying ready-made blocks is quite simple, since many factories are engaged in their production.
Among the advantages, it is worth highlighting the ease of assembly, which can significantly save time on the construction of the base. But, at the same time, prefabricated structures have some disadvantages. Not a solid structure and the need to attract heavy construction equipment reduces the popularity of this type of strip foundation.
For reference! If we talk about the price of the issue, then the difference between prefabricated and monolithic strip foundations is insignificant. Therefore, when choosing, it is worth focusing on the features of the structure.
The prefabricated strip foundation is assembled from ready-made slabs, and the joints between them are sealed Source kinozavr.info
3. Shallow foundation
This type of foundation is mainly used in the construction of light buildings. So, it can be frame houses and structures made of timber and logs. The peculiarity of such a base is that it is located slightly above the level of soil freezing. Therefore, it is often used on less problematic soils.
Shallow structures easily tolerate heaving of the soil, which occurs in winter. During construction, special attention is paid to waterproofing and thermal insulation. This will protect the base from the negative effects of the environment.
The advantages of a shallow foundation include its low cost of construction. At the same time, there is no need for complex earthworks. He has several shortcomings. First of all, it is worth noting that such a design can not be used on all types of soil and for the construction of not all structures.
The design of a shallow foundation is standard - it just goes deep into the ground by no more than 50-70 centimeters Source novostroika93.ru
On our website you can find contacts of construction companies that offer foundation design and repair services. You can directly communicate with representatives by visiting the exhibition of houses "Low-Rise Country".
The construction of a strip foundation of this type is carried out below the level of soil freezing. This makes it possible to distribute the load from the future structure on a stable layer of soil. Due to this, deep foundations are used for the construction of multi-storey buildings that have significant weight.
The advantages of this design is that they are suitable for the construction of heavy structures. It is also possible to equip the basement and basement. Of course, for the arrangement of the foundation, significant physical and material costs will be required. This is especially true for earthworks.
A deep strip foundation is buried below the freezing level of the soil - this can be 1.7-2.2 meters or lower, depending on the region Source diagnostics.spb.ru
Online foundation calculator
To find out the approximate cost of a strip foundation, use the following calculator:
Pros and cons of strip foundation
When choosing a foundation, you should pay attention to the advantages and disadvantages of one or another option. This also applies to the monolithic tape structure. The benefits include:
- the possibility of arranging a basement;
- ease of construction;
- low cost;
- high strength and reliability;
- possibility of application on heaving soils.
Unfortunately, the strip foundation has some disadvantages:
- in some cases there is a need for complex earthworks and the use of heavy construction equipment;
- the need for waterproofing and thermal insulation works.
It should be borne in mind that the concept of pros and cons is ambiguous, since everything here depends on the depth of the structure. Therefore, each type of foundation must be considered separately.
Materials for the manufacture of strip foundation
For the manufacture of the base will need various materials. It all depends on its type. So, for the construction of a prefabricated foundation, the following materials are used:
- concrete blocks and slabs of a certain brand;
- concrete for sealing holes between blocks;
- materials for waterproofing and thermal insulation.
Photo of the foundation with collapsible formwork:
One of the waterproofing options - it is laid even in the process of formwork assembly Source readmehouse.ru
Laying out a tape exclusively from blocks is almost impossible. Therefore, concrete mortar and even bricks are used to fill gaps. It is also recommended to arrange a reinforced concrete tape, which will allow you to connect all the elements into one.
As for the monolithic structure, for its construction you will need:
- boards or polystyrene foam for the construction of formwork;
- fittings for the manufacture of the belt and connecting elements;
- concrete of a certain class;
- heat and waterproofing materials.
When constructing a strip foundation for a house, it should be borne in mind that there is a need to carry out certain work. This applies to the arrangement of the pillow. To do this, you need sand or gravel, as well as waterproofing material.
Strip foundation design process
Foundation design is a very complex and responsible task, the solution of which is best left to professionals. In doing so, you need to determine:
- Soil type.
- Its calculated resistance.
- Linear loads.
- Burying depth.
- The width of the sole of the tape.
- Purpose and features of reinforcement.
- The possibility of arranging drainage.
Scheme for arranging drainage of a strip foundation Source krovli-zabori.ru
In order to determine these values, it is necessary to have certain knowledge. That is why it is better to entrust this work to professionals. Only they can do it well. It is worth remembering that the strength and durability of not only the foundation, but also the structure erected on it will depend on this.
Basement in a house with a strip foundation
The arrangement of the basement in a house with a strip foundation is a very time-consuming and costly process. To resolve this issue, it will be necessary to involve construction equipment and carry out false earthworks and concrete works. The arrangement of the basement is carried out in the following sequence:
- A pit of established dimensions is dug. If it is being built under the whole house, then heavy construction equipment will be needed for this. The process must be carried out very carefully so as not to bring down the ground.
- A crushed stone pillow is made along the bottom of the pit and concrete is poured. To give the floor strength, reinforcement is performed. The fittings should stick out a little around the perimeter, in those places where the walls will be installed.
- When the floor is completely hardened, the walls are reinforced and the formwork is installed for further concrete pouring. If the basement is installed only under a part of the house, then reinforcement is produced, which will later be connected to the reinforced belt of the strip foundation.
When constructing walls, special attention should be paid to their height. They must match the top of the foundation. After the construction of the foundation, the basement is covered by pouring a monolithic slab.
The depth of the strip foundation for the house
The depth of the foundation is calculated at the design stage. The recessed structure is installed so that its sole is 25 cm below the freezing level of the soil. This will protect it from uneven deformations that occur during frost heaving of the soil.
The height of the structure depends on the climatic features of a particular area. The freezing depth is determined by the formula. But, there is a ready-made table where you can find these values for a particular region.
Approximate depth of soil freezing in various regions of the Russian Federation and the CIS Source izchegopostroit.ru
If we talk about a shallow foundation, then it is located at a distance of 85 cm from the level of soil freezing. When constructing a structure, it is worth considering that it will have a low bearing capacity. Also, when constructing the foundation, it is worth considering the level of groundwater. The sole should be located at a distance of 20 cm from it. So, how to make a strip foundation?
Stages of erection of a strip foundation
Making a strip foundation is not such a difficult task. But in order to do the job correctly, you need to carefully study all the nuances and requirements. And it’s worth starting with drawing up a design diagram. It indicates the dimensions of the elements, which will make it easy to carry out its construction. Also, according to this scheme, you can calculate the required amount of materials.
The strip foundation technology looks something like this:
- ground preparation;
- work with formwork;
- waterproofing;
- frame reinforcement;
- concreting of the strip foundation;
Foundation preparation
At the preparation stage, calculation, marking and other equally important work are carried out. It is worth starting with a geological recovery - this work is entrusted exclusively to specialists.
Competent geological surveys require special equipment and specialized knowledge Source ro.decorexpro.com
In the process of geological recovery, the following should be determined:
- type of soil at the level of the sole of the base;
- ground water level;
After that, the occurrence mark and the thickness of the monolithic tape are calculated. When the geological penalties are over, they begin marking the site. To do this, use a wooden board and cord. You can also use lime mortar. With its help, a mark is made on the ground where the tape will pass. To simplify the task, the work is carried out using a pre-prepared foundation scheme.
Marking starts from one corner. After that, a side is planned. It is better to do it parallel to the fence or the road. Next, the other side is outlined, and so on. In this case, it is worth carefully checking the angles and diagonals. This will avoid problems with the construction of walls. The allowable error between the diagonals is 2 cm.
According to the markings, digging a pit or trenches is carried out. The first option is used in the construction of houses with a basement. Here you will need the use of heavy construction equipment.
Video description
Why the foundation is being prepared, see the following video:
At the bottom of the prepared pit or trench, a sand cushion is arranged. The thickness of the embankment can reach 50 cm. This parameter depends on the characteristics of the soil. The pillow is carefully compacted. This is done by vibrating or pouring water. A prepared layer is made on top of the pillow. For this, lean concrete is poured with a thickness of not more than 10 cm.
Formwork and waterproofing
The device of the strip foundation is carried out using the following types of formwork:
- removable, which is made of wooden boards;
- fixed, made of expanded polystyrene.
The peculiarity of the second option is that polystyrene foam plays the role of a heat and waterproofing layer. The formwork is set strictly according to the applied markings. It rises 10 cm above the foundation. To ensure the stability of the structure, it is supported by props from the inside and outside. A plastic film is laid in the formwork, which will prevent the flow of cement laitance.
On the inside of the formwork, mark the top point of the concrete. To do this, use a marker. In the process of carrying out this work, a hydraulic level is used. This will allow the concrete to be poured evenly.
Video description
What a fixed waterproofing formwork looks like, see the following video:
Frame reinforcement
For the manufacture of the frame, three types of reinforcement are used that perform a specific task:
- working longitudinal reinforcement with a diameter of 12 mm or more;
- horizontal clamps - from 6 mm;
- vertical clamps - from 8 mm.
Before you buy reinforcement, you need to calculate how much it will take to build the frame. In this case, it is worth considering the features of its design. The distance between the clamps is on average 25 cm. In the corners and at the joints of the walls, the step is somewhat reduced. When reinforcing, it is worth observing certain norms and requirements.
Video description
For more about reinforcement, see the following video:
Strip foundation concreting
Now you need to decide how to fill the strip foundation? If it is of considerable size, then it is better to order a ready-made concrete solution, which will allow you to pour the formwork in one go.
When concreting, you should follow some rules:
- Filling is carried out in one day. The break should not exceed two hours.
- It is necessary to drain concrete from the mixer from different points. If you stretch the solution, it will slightly reduce its quality.
- Concrete mortar can be dropped from a height of no more than two meters.
- The concrete solution is compacted with a vibrator or by baying.
It is better to fill the strip foundation at an average daily temperature, which is about 20 ° C. After completion, the structure is covered with a plastic film, which will slow down the loss of moisture.
Video description
Visually about the entire technology of creating strip foundations, see the following video:
Conclusion
The construction of a strip foundation, although it seems to be a fairly simple matter, but a lot of effort and materials are spent on it, and in terms of cost, this is about a third of the entire construction budget. A good foundation is calculated for the project of a particular house and it is better to entrust this work to professionals. Do not forget that the life of the building will depend on the quality and strength of the foundation.
An excellent option for the supporting part for a residential building will be a strip foundation with your own hands, step-by-step instructions will help you complete the work without errors. The result of the work will be a reliable foundation that even a brick building can withstand.
Types of strip foundation
Before you make a strip foundation with your own hands, it is worth studying its design features. Depending on the technology used, the tape is of two types:
- monolithic;
- team.
A - monolithic; b - prefabricated
A monolithic strip foundation will be a more profitable option for frequent construction. Prefabricated technology is more often used for mass development. This is due to the fact that concrete blocks and prefabricated reinforced concrete foundation slabs are used for installation. Such structures on average have a length of 1-2 meters and weigh from a couple of hundred kilograms to a couple of tons.
The device of the strip foundation from the blocks becomes impossible without the rental of lifting equipment: tower or truck crane. This significantly increases the cost of construction. In addition, in a small area there is a problem of placing mechanisms.
Filling the strip foundation avoids additional costs. This option is rational when building a house with your own hands. A few people will be enough to complete the work.
By design, the tape is of three types:
- deep-seated strip foundation;
- shallow;
- not buried.
The first option is suitable for the construction of buildings on any grounds. In this case, it is possible to make a basement or a technical underground for utilities. The device of a strip foundation of a shallow type is considered for small buildings and in the case of non-rocky soils with good strength (coarse-clastic, medium or coarse sands) on the site.
Unburied tape is used only for auxiliary buildings. You can put a gazebo or a canopy on it. Properly selected type of foundation will be the key to the success of all work.
To choose materials for the strip foundation, you need to decide on the technology. When using prefabricated elements, you will need to purchase:
- concrete blocks brand FBS;
- concrete slabs brand FL;
- brick and concrete for sealing holes;
- waterproofing materials;
- thermal insulation materials if necessary.
The sealing of holes made of brick or concrete is used because it is almost impossible to completely lay out an underground wall from standard blocks. Also, concrete and reinforcement will come in handy to make a tape concrete belt along the edge of the supporting part. A reinforced concrete element is necessary to bind the entire structure into a single whole. It allows you to evenly transfer the load from the walls to the underlying parts. If necessary, read the detailed article about foundations from FBS.
The technology of pouring a strip foundation involves the use of:
- liquid concrete of classes B15-B20;
- fittings: working, vertical, transverse;
- boards or polystyrene foam for the manufacture of formwork;
- waterproofing materials;
- thermal insulation if necessary.
Before you properly fill the strip foundation under the house, you will also need to prepare bulk material. Use sand of medium or large fraction, crushed stone, gravel or sand and gravel mixture. Such a pillow simultaneously performs several functions at once:
- aligns the base under the tape;
- performs the function of a drainage layer;
- prevents the negative effect of the forces of frost heaving.
Advantages and disadvantages
Before making the final decision to go deep with the help of the type of structures in question, it is worth studying the pros and cons of the types of strip foundation. The foundation tape deep laying has the following advantages:
- the possibility of building a basement;
- simplicity of technology;
- high reliability;
- application for heaving soils.
The recessed strip foundation also has disadvantages:
- large volumes of earthworks;
- high cost and labor intensity;
- the need for a drainage device;
- the complexity of the application at a high level of groundwater.
In some cases, a reasonable solution would be the installation of a shallow strip foundation. The option has the following advantages:
- reduced cost;
- there is no need for large volumes of earthworks;
- the ability to use when the GWL is located longer than 1.5 m from the surface of the earth.
But the construction of a strip foundation of this type is not available in all cases. This reinforced concrete option has several disadvantages:
- not recommended for heaving soils (if there is no other choice, they make reliable waterproofing, drainage, storm sewers and insulation);
- not suitable for buildings with a basement;
- cannot be used when the groundwater level is located above 1.5 m from the surface.
Strip foundation for the house: laying depth
This question should be the most important when designing a structure. The deepened strip foundation is supported so that its sole is 20-30 cm below the freezing mark. This is the only way to protect the building from uneven deformations during frost heaving.
The height of the strip foundation in this case depends on the climatic features of the area. The freezing depth is determined by the formulas. But with a simplified calculation of the dimensions of the supporting part, you can use ready-made tables developed for different cities of the country.
Depth of soil freezing by city
The shallow-depth design of the strip foundation assumes its laying at a distance of 70-100 cm from the surface level. It is important to remember that this option has a lower bearing capacity and is not resistant to the forces of frost heaving.
Before you start concreting under your house, you need to carefully select the depth of support of the sole. At the same time, not only freezing, but also GWL is controlled. General rule: water should not be closer than 20 cm to the base of the building.
The foundations of low-rise buildings usually do not need a detailed calculation. All values are assigned by eye. In this case, there is a high probability of overspending. But if possible, it is better to turn to specialists who will accurately select the laying, width and reinforcement. If this is not possible, use the minimum values:
- height depending on soil freezing;
- width, depending on the width of the wall (the value for the foundation is taken not less, but better a couple of centimeters more);
- working reinforcement with a diameter of 12 mm;
- clamps with a diameter of 6-8 mm.
How to do it right: step by step instructions
Making strip foundations is not such a difficult task. But you will need to carefully study all the nuances and nodes for private houses.
Strip foundation: device diagram
First of all, a strip foundation scheme should be prepared. It lists all sizes. Such a drawing will not only make it easy to make a recessed strip foundation, but also calculate the required amount of materials in advance.
Example of a working drawing with dimensions
There is a certain order of work, according to which the strip foundation is poured, the technology is as follows:
- preparation and marking of the site;
- excavation;
- installation of formwork and its waterproofing;
- installation of a metal frame;
- do the pouring of the strip foundation with their own hands;
- set of strength and care of concrete;
- stripping works;
- waterproofing, insulation.
Training
How to make a strip foundation? - Answer: make geology and calculation. You will also need to clear the area and remove debris.
Geological surveys are carried out by specialists. In a simplified version, you can make them yourself. In this case, holes are torn off or wells are drilled to a depth that is 50 cm higher than the laying of the tape. The main task at this stage is to determine:
- type of soil at the level of the base of the underground wall;
- groundwater level.
After testing, they finally take the mark of occurrence, and also assign a cross section depending on the strength characteristics of the soil. With high accuracy, only an engineer will perform such work.
Plot marking
For marking use a wooden cast-off and a cord. Another option is to draw lines across the ground using lime mortar. How to pour the foundation under the house with high accuracy? You need to try at the markup stage. In advance, it is worth preparing a strip foundation scheme, which subsequently needs to be taken out to the area. The drawing made is needed so that all dimensions are at hand.
To markup, first mark the first corner. After that, a side is built from this point. It is easier if this side is parallel to the fence or road. The next step is to build a right angle. In such a situation, you need to use the Egyptian triangle method.
Cast-off stakes should be placed at a small distance from the outer walls of the building. This will prevent the cord from sagging when developing a trench or pit. After the markup for a square or rectangular building is prepared, it is worth checking the dimensions of the diagonals. They must match. Deviation up to 20 mm is allowed. A house that is complex in plan can be broken down into simple shapes.
To prepare the base for heavy equipment, you will need to mark out separate foundations. The expansion joint between them and the main tape is taken to be at least 10 cm. After pouring the structures, this space is filled with loose non-combustible material.
Soil development
Technology involves a large amount of work. Most likely, it will be necessary to attract additional equipment: an excavator, dump trucks to transport the soil outside the site. The scope of work depends on whether the building will have a basement:
- if available, dig a pit;
- in the absence - trenches.
When performing earthworks, it is imperative to remember safety precautions. The width of the trench must be such that formwork can be installed in it. The walls are made with a slight slope. To prevent shedding of the soil, temporary supports are installed. Do not work in the trench alone. There should always be another person on the surface who will help in case of danger.
The dimensions of the trench or pit should provide unhindered access for workers to the side surface of the underground wall. This is necessary in order to make future insulation and waterproofing of the basement. The width on each side of the tape increases by about 80 cm.
sand cushion
A sand (crushed stone or gravel cushion) is laid at the bottom of the pit or trench. Its thickness is assigned depending on the strength of the soil from 20 to 50 cm. The weaker the soil, the thicker the backfill is needed. The same rule applies to heaving.
Sand cushion - the lowest layer of the base
The cushion must be level throughout. When laying it, it is compacted in layers (the thickness of the layer for compaction is taken to be no more than 15-20 cm. Compaction can be done by vibrating or pouring water. The method of pouring is not recommended for use for clay soils, since they have a low filtration coefficient.
On top of the pillow, a concrete preparation is made of lean concrete B 7.5 with a thickness of 5-10 cm.
drainage system
Drainage at the level of the sole of the tape is used not only at high GWL. For the device, drainage pipes with a diameter of 110 to 200 mm are used. The choice of diameter is carried out depending on the geological conditions of the site. Pipes are laid with a slope of 0.003-0.01.
Drainage is mounted in a layer of crushed stone with a fraction size of 20-40 mm. It performs a filtering function and prevents clogging of pipes. To prevent crushed stone from spreading, it is wrapped with geotextile.
Drainage device at high GWL
When installing a drainage system, several rules are taken into account:
- pipes should be 30 cm or more below the foundation foot mark;
- the maximum distance from the outer edge of the house to the drain is 1 m.
The output of the system is carried out in an open area, in a septic tank or sewer.
Formwork
Formwork for reinforced concrete foundations is of two types:
- removable (from wooden boards);
- fixed (from expanded polystyrene).
The second option also performs the function of thermal insulation and additional waterproofing. The formwork is set strictly according to the markup. Its height is assigned 10 cm higher than the foundation. Supports are mounted on the outside for stability. Jumpers can also be provided inside the structure. The first mounted node is a corner one. A plastic film or roofing felt is placed in a wooden formwork, which prevents the flow of cement laitance.
The upper edge of the formwork is placed 2-5 cm above the concrete mark. This will allow the mixture to be compacted without problems. She won't splash. The fill mark is drawn on the inner surface of the formwork with a marker.
Reinforcement installation
Reinforcing cages consist of three types of rods:
- working longitudinal diameters from 12 mm;
- horizontal clamps with a diameter of 6 mm;
- vertical clamps with a diameter of 8 mm.
All connections are recommended to be made on a knitting wire. Welding weakens the reinforcement and does not give a high guarantee. Even if the rods are connected along the main length with a welding machine, wire is used at the corners. To reduce labor intensity, a knitting gun is used.
Reinforcing cage placement pattern
in strip foundation
The pitch of the clamps is prescribed on average 20-30 cm. In the places where the walls adjoin each other, the pitch is halved. Before performing work, it is worthwhile to carefully study the methods of reinforcing the foundation at the nodes. Read the rest of the rules and recommendations in the article about the reinforcement of the strip foundation.
Pouring concrete
Before pouring the strip foundation under the house, it is recommended to order the mixture at the factory. This allows you to work without interruption. Also, in the factory, it is easier to observe the proportions of the components, which are very important. By adding a little more crushed stone or sand, you can get weaker concrete than required.
Pouring concrete
It is recommended to use material of classes from B15 to B20 for pouring. The heavier the house (from frame to brick), the more durable concrete will be required. Filling is desirable to perform in one day (without stops). This is the only way to prevent the appearance of concrete joints that weaken the structure.
When performing work, you should follow the basic rules:
- pouring is done in one day with maximum breaks of 1-2 hours;
- the mixer moves along the perimeter of the building, dispersing the mixture from one point reduces the quality of the material;
- the maximum height from which the solution can be dropped is 2 m;
- concrete must be compacted after laying with a vibrator or bayonet.
Concrete care and stripping
Before you build a house, you need to study the weather forecast. Filling is recommended at an average daily temperature of +20 degrees Celsius. In hotter weather, the quality of the material decreases, in colder weather, the hardening rate. In total, it takes 28 days to set strength.
Immediately after pouring, the structure is covered with polyethylene, tarpaulin or burlap. This will prevent moisture loss too quickly. The formwork can be removed upon reaching 70% of the branded value. With an average daily temperature of +20°, this will take one or two weeks.
The film maintains the required humidity conditions during curing
During the first week after laying the mixture, you need to water it with water at intervals of a couple of hours. This will avoid the appearance of cracks on the surface of the structure. One way to wetting the surface is to spread sand or sawdust over the concrete; these materials are already wetted during care. They will gradually release moisture to the concrete.
Warming and waterproofing
Moisture isolation is a must. It includes:
Insulation is performed if necessary (if a warm basement is planned). For these works it is not allowed to use mineral wool. The best option would be extruded polystyrene foam ("Penoplex").
Do-it-yourself strip foundation: step-by-step instructions with a photo
All about how to properly fill a monolithic strip foundation: the pros and cons of technology, instructions for pouring, installing and building a foundation strip
