Walls made of foundation blocks. Foundation from FBS blocks - we build a reliable foundation in the shortest possible time FBS blocks reviews wall construction

FBS blocks are a solid structure made in the form of a parallelepiped and equipped with mounting loops. The end faces of the product have special recesses, which are filled with liquid during the construction process. So in a simple way the strength and integrity of the foundation structure made of FBS blocks is ensured.

The overall dimensions of the FBS are regulated by the state standard. Standard sizes differ in length and width, but the height of all modifications is constant and equal to 600 mm. True, some manufacturers produce blocks 300 mm high.

The weight of the FBS does not allow the work to be done manually. Trying to install them using a winch is fraught with enormous labor costs. So you can’t do it without a crane. This very significant drawback explains why FBS foundations for individual houses are very rarely built.

The disadvantages include the lack of reinforcing elements inside the FBS. To strengthen the foundation, the blocks are laid on reinforced concrete foundation slabs - pillows.

Construction of a foundation from FBS blocks: step-by-step instructions

The block foundation for a house is a simple structure consisting of:

reinforced concrete pad;
walls made of FBS;
waterproofing.

In some cases, the structure is supplemented with an upper armored belt.

The construction of a foundation from FBS blocks is carried out in several stages.

Stage one - preparatory work

At this stage it is being developed project documentation. There are now many computer programs available that can lay out blocks. But if you don’t know how to use them, draw the masonry on paper, just do it not arbitrarily, but to scale.

Based on the drawing, it will be easy to understand the order of installation of FBS and their dressing.

At this stage, the entry points for utility lines are determined. There are masonry elements on sale in which passage holes are created. If you miss this moment, you will have to drill them into your body concrete block This will lead to additional time, financial and labor costs.

The width of the foundation depends on the thickness of the walls of the above-ground part of the building. For wooden buildings, 300 mm is sufficient. Width of foundation made of FBS blocks for brick house usually taken at 600 mm.

Stage two - excavation work

Inspect the construction site for the organization of access roads for special equipment. Remove everything that will interfere with further actions: bushes, trees, debris, etc.

After this, remove the fertile layer 150-200 mm thick at the building construction site. It can be carefully folded away from the pit: in the future, the turf will be useful when arranging a garden or vegetable garden.

Before making a foundation from FBS blocks, it is necessary to mark it on the ground (). This is done using pegs and cords.

The following are brought to the area:

external and internal contour of the foundation.

A trench is dug according to the markings. Its depth should exceed the freezing depth of the soil by 200-250 mm. There are regions in Russia where the soil freezes up to two meters deep. It is not economically feasible to build a foundation using FBS blocks for a house in such places. Typically, a block base is used where this parameter does not exceed 0.8-1 m.

Stage three - arrangement of the sole

When you start laying the blocks with your own hands, you will need to choose the type of base for the foundation.

There are two options to solve this issue:

build a sand cushion;
pour the concrete base.

The second option is used in the case of unstable soils. It costs a lot of money, significantly slowing down the speed of construction. Therefore, in the absence of objective reasons, it is better to refuse it. In most cases, it is enough to equip a sand cushion.

Work at this stage is carried out in the following order:

the walls of the pit or trench are leveled;
a 10-15 cm layer of sand is poured into the bottom of the pit;
the sand is spilled with water and thoroughly compacted;
crushed stone is poured over the sand layer (layer thickness - 100 mm) and also compacted.

These operations are the same for both options for arranging the pillow. If there is a need for a base, it is mounted on top of the crushed stone, and a reinforcing mesh is placed inside it. Then the concrete mixture is poured ().

On weak soils You can increase the area of the foundation base using reinforced concrete foundation slabs FL. they are laid on the sand-crushed stone preparation completely or at intervals of up to 70 cm. In the latter case, the space between separate elements must be filled with soil, carefully compacted.

How to put a foundation of blocks on pillows? The first row of FBS must be laid in such a way that their vertical joints (or seams) are located on the slabs. Based on this condition during design, the maximum permissible gap between concrete pads is determined.

Stage six - laying blocks

At this stage, we proceed directly to creating a foundation from FBS blocks: how to lay the blocks:

The laying of each row begins with the installation of beacon blocks. They are placed in corners and intersections of walls. Vertical seams filled with solution. If the overall size of the foundation is not a multiple of the length of the blocks, a gap will form at the end of laying the row. It must be filled with concrete, after installing the formwork;
all subsequent rows of the foundation made of FBS blocks for a house must be laid on a layer of mortar. Its thickness is 1.5 cm. Be sure to bandage the vertical joints at 250-600 mm. If this rule cannot be followed, use masonry mesh or reinforcing bars;
The quality of work is regularly checked using a building level.

Experienced builders try to choose longer products to build a foundation from FBS blocks. Thus, they reduce the number of vertical seams, thereby increasing the strength of the structure and its reliability.

Stage seven - waterproofing

IN step by step instructions foundation from FBS blocks, this stage is the simplest. It is necessary to coat the surfaces of the structure with liquid mastic - internal and external, paying special attention to Special attention seams.

If the construction site is located in a region with frequent and heavy rainfall, it makes sense to cover the foundation with roofing material after coating.

Stage eight - armored belt

How to make a foundation from FBS blocks with your own hands to eliminate the risk of its destruction? It can be reinforced with a reinforced concrete belt cast along the top row. In the future, floor slabs will rest on it.

Many professional builders consider this step unnecessary, but practice shows that during construction block foundation with your own hands (most often, inexperienced ones), such a step is completely justified.

The reinforcing belt is constructed in the following order:

Formwork () is installed along the perimeter of the foundation (on the outer and inner sides of the walls). To prevent the panels from moving apart from below under the pressure of the concrete mixture, they are tied together with wire. They are fastened at the top with clamps or pins;
a reinforcing frame or mesh is lowered into the formwork;
concrete mixture is poured ().

The formwork is dismantled after the concrete has hardened (). To facilitate this operation and prevent leakage of the solution at the time of pouring, it is advisable to cover the internal surfaces of the boards with polyethylene film before installing the reinforcing mesh.

Conclusion

In this article, we tried to answer the question: how to build a foundation from FBS blocks, highlighting the most important points of this process. This technology is highly labor-intensive, but does not present any particular complexity.

If you carefully carry out all operations, even those that may seem not particularly important, the result will be a foundation for a house that is built according to all the rules and can last for decades.

Video on how to properly make a foundation from FBS blocks.

A foundation made from FBS blocks has several advantages that no other type of foundation has. FBS (wall foundation block) and FBP (hollow foundation block) are made from light, silicate and heavy concrete, expanded clay concrete. FBS blocks can have a reinforced frame, or have only mounting loops. The ends of the blocks have technological grooves into which cement mortar is placed during installation. Let us consider in detail the construction of a foundation made of FBS blocks.

An important point is that the blocks are produced in standardized sizes; the number of standard sizes is sufficient to form almost any design of strip and columnar foundation, as well as their variants. The width of the blocks is selected to match the thickness of the building walls.

Pros and cons of foundations made of FBS blocks

The use of a foundation made of FBS blocks has its advantages and disadvantages. To understand the objective picture, let’s consider them in detail.

Advantages of a foundation based on FBS blocks

The advantages of choosing and constructing a foundation from FBS blocks are as follows:

speed of construction and simplicity of the device, which does not require special skills
work can be carried out regardless of air temperature and weather conditions, both in rain and snowfall
structure finished design not absolutely rigid, but has some flexibility and mobility due to the joints. A rigid strip monolith is subject to greater loads under the influence of frost heaving forces than a flexible block monolith.

Disadvantages of a foundation based on FBS blocks

But you should also forget about the shortcomings, we list them:

installation requires special lifting equipment
the presence of joints that weaken the structure requires serious waterproofing
despite the high bearing capacity, it is not applicable on clayey and heaving soils, as well as on subsidence and insufficiently dense soils

It is recommended to choose a foundation made of FBS in areas with dense sandy, rocky foundations, and soils containing crushed stone and gravel-pebble deposits without interlayers of loam. Ideal conditions are low groundwater, not reaching the base and the base composed of dense sands of medium and coarse grain. Such a base will provide natural drainage and will not swell or sag depending on the temperature. But such conditions are extremely rare, so proper preparation of the base is very important.

Preparation of the base on dense sandy and gravelly soils consists of constructing a 150 mm high cushion of river or quarry sand, compacted layer by layer in a wet state. On medium-density sands, an additional bottom layer of crushed stone cushion with a thickness of 100-150 mm is required. In both cases, the top layer of sand is moistened with water and compacted until the trace of the sole is not visible.

When building with FBS blocks in conditions of high groundwater, a drainage backfill made of coarse washed sand that does not contain clay is required. If there is a high groundwater level and underlying soils are loams and sandy loams, then these soils need to be replaced. In addition, with a high groundwater level, serious waterproofing is required - with liquid rubber or adhesive.

The preparation of a clayey base prone to heaving is more complex and involves the installation of an additional monolithic reinforced cushion. The pillow should protrude beyond the contour of the block foundation by 100 - 200 mm on the outer and inner sides. The thickness of the cushion (from 100 to 300 mm) and reinforcement are taken by calculation, depending on the strength of the underlying soil. The bottom row of the foundation is laid out from FL blocks, which have the shape of a trapezoid with an expanded base. This device increases the resistance of the foundation to forces caused by soil movements.

The design of a block foundation, including lower and upper reinforcing belts 50-100 mm thick, which can begin and complete the laying, and also alternate through two rows of blocks, provides insurance and does not allow the blocks to “travel” along with uneven subsidence and heaving of the soil. Such a device is included in construction practice and justifies itself.

The dimensions, plan and height of the required excavation are dictated by the project, depending on the availability of the basement. If there is a basement, then a foundation pit and a concrete screed for the floor are required. If a basement is not needed, then they dig a trench. In addition, when calculating the required size of the excavation, it is necessary to take into account that this size should provide, in addition to the installation of blocks with adjustment with crowbar, the possibility of arranging formwork for armored belts and all work on the construction and compaction of the base cushion.

The alignment of the foundation axes is carried out using a laser rangefinder and a theodolite. The reference points are reliably marked by driving metal beacon pins. Moorings - a stretched fishing line or cord connecting pins in pairs to form the axes of the walls. You cannot divide the distance between the beacons of one wall into separate segments, this will lead to the accumulation of a static error, which will result in a deviation and a curved foundation line. A mooring is also needed to control the vertical position of the blocks during installation; the gap between the mooring and the block is allowed no more than 2 mm. The masonry horizon is checked building level or using a laser level, which will be more reliable.

Step-by-step instructions for constructing a foundation from FBS blocks

Sequence of installation of a foundation based on FBS blocks:

Beacon blocks are installed first, defining corners and intersections of load-bearing walls
The first row of blocks is placed between the beacon blocks, filling the vertical joints with cement mortar to a thickness of 20 mm. If necessary, use additional elements, not forgetting to leave design holes for communications. The edges of the holes are strengthened or sleeves are inserted; after laying the pipes, the gaps are filled with concrete.
the second row of blocks is mounted with ligation, similar to brickwork. But with the difference that the indentations from the edges of the blocks of the first row are taken not for reasons of aesthetics, but based on the strength of the foundation soils. If below heaving clay, then the vertical seams of the dressing are made in the middle of the block of the bottom row. If the base is strong, the indentation from the edge is made at 0.4 - 0.5 of the height of the mounted block.

after the top row of blocks is installed, the armored belt is poured. Reinforcement is performed with three rows of rods or a mesh. The armored belt levels the top of the foundation under the walls and increases the reliability of the structure.
horizontal and vertical joints between blocks are filled with mortar to the full depth; there should be no empty space. Joints between blocks are made both outside and inside.
small areas can be covered not only with additional blocks, but also with brickwork or monolithic.

If the site has high level groundwater above the base of the foundation, then all walls are waterproofed with adhesive or coating insulation, and as a more reliable option - with liquid rubber.

Backfilling of trenches and pits using river or quarry sand is carried out in layers, with compaction of each layer using a tamper.

Foundation building blocks (FBS) are worthy products for arranging reliable foundations for various buildings. They, having a number of operational and installation advantages, have recently been often used by private developers.

FBS - specifically for foundation construction

The blocks in question are reinforced concrete elements made from high-grade heavy concrete. They are reinforced with metal rods (due to this they can withstand serious loads) and look like rectangular parallelepipeds. FBS are often equipped with special eyes that facilitate the process of loading them at the factory and unloading them at the construction site. In addition, special recesses are provided at the ends of the products. During installation, a liquid concrete solution is supplied into them, which connects the individual blocks to each other as tightly as possible.

The service life of a foundation made of FBS blocks is more than 100 years. Minimize deadlines construction work- order FBS blocks and concrete of any brand on the website "Concrete 174"

Basic tech. The characteristics of foundation products are as follows:

water resistance of concrete – W2;
compressive strength – B12.5;
frost resistance – F200;
density – within 2400 kg per cubic meter;
strength – about 110 kg/cm.

The geometric sizes of blocks vary. This allows consumers to select the optimal products for the construction of any foundation. The most popular standard sizes of FBS are as follows: height and width – 0.3–0.6 m, length – 2.4; 1.2; 0.9 m. But if necessary, it is easy to order products with other parameters.

The starting raw material for the described blocks is most often expanded clay concrete. Technology production of FBS quite complex and time-consuming. It involves the use of special equipment - forced concrete mixers and large deep vibrators. The process of obtaining a block with specified technical parameters takes more than 30 days. Since FBS is usually used for the construction of foundations, manufacturers additionally treat the surface of the products with composite compounds (water repellent plus bitumen). Such coatings perform the function effective waterproofing, which well protects blocks from the influence of atmospheric, melt and groundwater.

Is it possible to build a good foundation quickly and inexpensively?

The key advantage of the products we are interested in is the guaranteed speed of arranging foundations for various buildings. Moreover, a foundation made of FBS blocks can be built in any weather. Neither heavy snowfall nor rain is an obstacle to such construction work. Other advantages of foundation blocks:

Easy and simple do-it-yourself installation. Problems can only arise when lifting blocks of large mass. You can’t handle this task yourself; you’ll have to order a crane.
Flexibility of the resulting foundation. Non-monolithic foundations are built from FBS. There are joints between individual products. Due to its flexibility, the foundation can be built on sandy and many other problematic soils. It is not recommended to build foundations using building blocks only on very soft soils. In this case, there is a possibility of it bending due to strong heaving of the earth.
Minimum construction costs. The affordable cost of the blocks reduces the cost of work. Cost reductions are also achieved due to the fact that almost all foundation construction operations can be performed independently.
High moisture resistance, low thermal conductivity, increased frost resistance.
Unique durability. Buildings on FBS stand without accidents for up to 160 years!

Let us immediately note that all foundation products are required to be supplied with certificates. They provide technical block descriptions. Before purchasing products for building a foundation for a house or other structure, we strongly recommend that you read the data in the certificate. Purchasing low-quality blocks will not allow you to take advantage of the benefits that are inherent in high-quality FBS.

The downside of the products in question is that when building a foundation, they need to be protected from moisture and also thermally insulated. These operations are not that complicated. But, nevertheless, they increase the cost of money, time and physical effort. And don’t forget that you will have to spend extra money on ordering a crane to lift heavy blocks.

Let's start arranging the structure - let's start with digging

In private construction, FBS is recommended for arranging strip-type foundations. Such prefabricated foundations are suitable for houses with several floors, and for garages, and for any outbuildings. buildings Before starting the main work, it is necessary to draw up a construction plan, calculate how many blocks and what sizes are needed for the walls of the foundation being built. We also determine the method of knitting products and the areas of the foundation through which they will be laid. engineering Communication(you need to order FBS with holes). After this, you can purchase the required amount of materials.

The first step of arranging the foundation is standard. Digging a pit. To determine its exact depth, we recommend ordering a simple geological survey in advance. It describes the properties of the soil and the characteristics of the flow of soil water. The cost of such research is low. And the benefits from it are enormous. We recommend taking the trench depth 20-25 higher than the soil water level.

Then we level the bottom of the hole and place a two-layer cushion on it - 10 cm of crushed stone plus 5 cm of sand. We spill the resulting cake with water and compact it as thoroughly as possible. As a result, we should get a dense and even pillow. Fill its surface with concrete mortar (two-centimeter layer). We are waiting for the last one to dry. In some cases, a solution for pouring a sand-crushed stone cushion is not made. Instead, a regular masonry mesh is mounted on it. It eliminates the risk of gaps and holes appearing between the individual blocks that will make up our prefabricated foundation.

How can a self-taught craftsman create a solid foundation?

Laying the foundation from the block products in question has some features. We definitely need to make an additional foundation that will not allow the FBS to sag during the operation of the building. It makes the most sense to make such a special sole in the form of a concrete flat slab. Its construction requires materials and time. If there is a light structure on the foundation, the slab may not be poured. It is successfully replaced by a number of FBS. But in this case, their height is considered as width. In other words, we will simply need to lay the products on their sides. This technique is not used if the foundation for a house is being created.

Step-by-step instructions for pouring the slab are as follows:

1. We make formwork from edged boards, controlling its position with a hydraulic level.
2. We knit reinforcement (F12).
3. We fill the slab.

After the sole has hardened, you can begin laying the blocks. We begin the procedure with the installation of corner FBS. We join the products as tightly as possible. We coat the seams with a composition of. Using this method, the first row of the foundation structure is installed. It is very important to ensure that it is perfectly level horizontally.

Next, we proceed to the installation of the second and subsequent rows of the foundation being built. They should be placed in a sling. This means that the seam (vertical) of each product from the top row must fall strictly in the middle of the FBS from the bottom line. All gaps between the blocks are filled with cement. We do not spare material! There should be no gaps between the blocks.

At the corners of the building, it is advisable to install block products with an overlap. How to do it? Not difficult. It is necessary that the corner of the first row falls on the edge of the building block from the right wall, and the corner of the second row from the left, and then in turn. When installing each FBS, we check the accuracy of installation (both vertically and horizontally). The outer walls are always laid out first, the inner walls are built after them.

As you can see, the process of laying a strip foundation cannot be called complicated. Any novice builder can handle it. The following tips will help facilitate the construction of the structure:

1. In cases where the calculation of the base was not carried out in the most accurate way, and the foundation blocks do not coincide with it, it is allowed to install them with a slight plumb line at the corners (100 mm from one edge or 50 mm from both).
2. If during the laying process there is a place in the row where the whole FBS does not fit, there is no need to cut out a suitable size piece from the whole block product. It is much more convenient and smarter to fill the hole with cement or simple building bricks.
3. Decide in advance on the date for which you will order a crane for lifting and installing blocks. Then the work process will not be delayed.

Last tip. If a private house cocked without ground floor, and the soil on the site has a high bearing potential, the base can be made intermittent rather than continuous. In this case, the blocks are placed at 50–70 cm intervals. The latter are covered with earth and pressed. Construction costs for intermittent structures are reduced by 10–15% due to the fact that fewer blocks need to be purchased.

Not all owners of private houses are lucky with an ideal landscape on their site. Often there is a need to strengthen the slope in places where there is a difference in height. If the difference in elevations is insignificant, geogrid or biomats are used. If the ground level in the local area changes greatly, a retaining wall made of blocks can solve the problem.

A retaining wall is vertical design, which prevents soil movement. There are several varieties that can be divided into two large groups:

thin walls;
massive walls.

A retaining wall made of concrete blocks belongs to the second group. Its stability is ensured by the structure's own weight. When constructing such a structure, it is necessary to correctly select the thickness of the blocks, depending on the height difference and soil characteristics.

FBS blocks have been used in construction for a long time. And now they have not lost popularity due to the following advantages:

High speed of work. Factory-made blocks are completely ready for use. There is no need to waste time hardening the concrete.
Favorable cost when using standard blocks.
Simplicity of installation technology.

Concrete blocks are widely used by construction companies. When choosing this type of retaining wall for a private home, it is worth considering several features:

The need to use lifting equipment. Depending on the size, one element weighs from several hundred kilograms to several tons. It will not be possible to install such a load manually.
The large mass will also affect transportation costs. Shipping products from factory to site can be expensive.
Demand for qualified specialists. To securely attach the element to the hook of the lifting equipment, the help of a slinger is required. There may also be issues with unloading, storing and installing in the design position.

FBS retaining wall with buttresses, plan view.

Before using foundation blocks for private construction, you need to carefully weigh the pros and cons.

Design

At the design stage, the following issues are addressed:

assignment of geometric dimensions of the wall;
determination of design features;
calculating the need for materials and drawing up estimates.

Geometry and design features

The geometric dimensions of the wall depend on the height difference and strength characteristics soil. Accurate calculation of parameters is performed based on the following documents:

Design Guide for Retaining Walls and Basement Walls for Industrial and Civil Engineering.
SP 43.13330.2012 (clause 5.1).

When designing a structure, it is important to prevent tip-over. On one side the soil presses on the wall, but on the other there is no support. It is this feature of operation that leads to the fact that the reinforcing element is deformed and displaced.

The FBS retaining wall is made taking into account the minimum thickness for this type of structure - 400 mm. If the structure is high, the blocks are laid out in steps. In this case, the sole is made up of blocks 600 mm thick (width), and the upper part is made of blocks 400 mm thick. This technology allows reducing material consumption while maintaining reliability. There is also the option of building a wall on a reinforced concrete slab.

Important! If the wall is long, it is necessary to provide buttresses. The buttress is a rib assembled from FBS blocks (or monolithic). Most often, such ribs are laid out in steps. The buttress must be connected to the main wall. The spacing of the ribs is determined depending on the load on the wall and its height. On average, it is taken to be 2000-4000 mm.

Dependence of the maximum height of a retaining wall on its thickness and the angle of internal friction of the soil.

Construction materials

Prefabricated retaining walls made from FBS blocks. During production, they are guided by the 1.116.1-8 series. To reduce construction costs, it is recommended to use the standard dimensions of the elements, which are given in the specified document.

Blocks come in different lengths, widths and heights:

length - 880, 1180, 2380 mm;
width - 300, 400, 500, 600, 700 mm;
height - 300, 600 mm (blocks 300 mm high are only 900 and 1200 mm long).

Main dimensions of FBS blocks.

The series and factories for the production of concrete products use markings that indicate all the necessary characteristics. An example of marking is as follows: FBS 12-4-6, where FBS is the wall foundation block, 12 is the length in dm, rounded to whole numbers, 4 is the width in dm, 6 is the height in dm.

To order the required number of blocks of each size, it is recommended to first draw a wall layout (front view). The diagram requires you to indicate the ligations of blocks in adjacent rows to each other. There should be no long vertical seams. The minimum dressing size is 250 mm.

The blocks are made of concrete. To strengthen the structure and increase bending strength, reinforce the horizontal seams. For this, a mesh of steel reinforcement with a diameter of 3-4 mm with a cell pitch of 50-100 mm is usually used. Required amount metal should also be calculated in advance.

Construction

A retaining wall made of FBS blocks is made in almost the same way as a strip foundation. The work is performed in the following order:

marking the territory;
soil development;
installation of a base under the wall (soil compaction, laying a sand cushion, pouring a concrete base, etc.);
erection of a wall;
drainage device;
backfilling.

To mark the territory, you can use a cast-off and a cord attached to the cast-off with nails or self-tapping screws. In this case, the markings will not interfere with the development of the soil. After this, a trench is dug. The depth is determined depending on the depth of the wall. It is important to take into account the thickness of the sand cushion and concrete base (if provided).

A sand cushion will help level the surface. Sand can also act as a drainage layer and protection against the forces of frost heaving. The thickness of the pillow is usually set in the range of 300-500 mm. Laying is carried out with layer-by-layer compaction. The thickness of each layer should not exceed 150-200 mm. To compact sand, you can use the simplest and most inexpensive method - pouring water.

The first row of blocks is laid on a cushion. A reinforced seam approximately 20 mm thick is provided between the horizontal rows. Loading equipment will be required for installation.

Important! Each factory-made block has special mounting loops for slinging. After installation in the design position, the hinges are cut off.

Drainage device

The process of backfilling and construction of drainage occurs almost simultaneously. At this stage it is necessary to prevent the accumulation of moisture in the upper level. We are talking about rain and melt water. Drainage usually consists of several parts:

a drainage tray, for example, a concrete one with a lid to protect it from debris and leaves;
layer of drainage material;
drainage pipe along the entire wall;
drainage pipe.

The drainage tray is located at ground level. It is necessary for organized water collection. Trays can be open or closed (with a protective grille on top). The most commonly used are concrete and plastic trays.

The drainage layer is backfill. It can be made of crushed stone, gravel or a sand-gravel mixture. Such materials allow water to pass through well, preventing it from stagnating near the surface. Through the drainage layer, moisture is removed into the drainage pipe.

The diameter of the pipe is determined depending on the volume of precipitation and soil moisture. On average, it is taken in the range from 100 to 200 mm. Removing moisture from drainage pipe carried out using drainage pipes. Water with top level(behind the retaining wall) is brought out to the bottom. This prevents damage to the structure and a reduction in its service life.

Important! Drainage pipes must be laid into the wall during the construction process. Their step depends on the climatic characteristics of the area and the geological characteristics of the soil. The higher the amount of precipitation and soil moisture, the more often the tubes should be placed.

A massive FBS retaining wall is an economical and reliable option. But during its construction it is necessary to take into account several very important points. In some cases, it would be more reasonable to replace such a solution with another type of fortification structures.

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Bulky slabs of reinforced concrete have been eliminated from private construction for a long time. Now capital foundation It is customary to make it from durable material that can withstand up to 7-8 floors. We're talking about FBS block. Since there is a demand for this type of building material, it means that there are distinctive characteristics. Which we will describe further.

Advantages and disadvantages of a foundation made of FBS blocks

Positive characteristics:

You can save time without mixing concrete. It is easy to calculate the material and maintain the proportion.
Manufacturers try to produce such blocks so that the installation process did not require any special equipment. An ordinary tap is enough.
Some types of blocks provide grooves that further strengthen the structure.
Applicable on any soil. Suitable for any climate. Frost and excess moisture are not scary. The material itself is highly resistant. Impregnated with a special substance that prevents the destruction of the block.

Natural disadvantages:

Price.
Installation only with special equipment.
A block structure is not a monolith. The risk of drawdown cannot be ruled out.
Need a good level waterproofing. Although any type of foundation for a private house must be sheathed and protected from external influences.

Dimensions of foundation blocks, GOST

Naturally, the manufacturer provides the strength and geometry characteristics established by GOST 13579-78. Otherwise, at the slightest deviation, destruction of the building cannot be avoided. A typical block for an FBS foundation is a parallelepiped cast from expanded clay or silicate. The density should be from 1800 kilograms per cubic meter. No voids are provided. Technological preforming is required to ensure vertical reinforcement of the masonry with cement mortar.

There is also a strength class for this building material. According to the standard, it should not be lower than B 7.5.

Foundation structure: diagram and types

FBS blocks can be used on:

It is advisable to give preference to the first option if you plan to build bathhouse or two-story residential building with a 6x8 or 8x8 base. It is also customary to select these blocks for complex soil with high acidity. For a residential building, a columnar structure made of FBS is ideal if the object itself is assembled using a panel method.

The tape type base in one row is good for an oversized low-rise building, for example, an ordinary dacha without a basement. But if there are significant loads on the foundation, it is better to abandon FBS blocks in favor of a monolith. The blocks can still cope with the load, but there is always shrinkage of the building. This is where the lack of material will be reflected - the seams may come apart in some part of the structure after a few years. This occurs when saving on a sand-gravel cushion or complex soils.

Waterproofing foundations made of FBS blocks

During the construction process, they begin to create only after all the rows of the foundation have been installed. Here's how to do it yourself:

In general, there are several types of waterproofing for block foundations. Classified:

Plastering. It is done using cement mortar to which some additives are added. It's better to apply liquid glass. This way the foundation will be protected from the accumulation of moisture inside the material and room.
Pasting. A simple, inexpensive type of waterproofing. It is necessary to purchase a waterproof material based on bitumen. It is simply processed with a burner and, already heated, applied to the outer part of the base. There are special materials for waterproofing that have a self-adhesive surface. You don't even need a burner with them. Usually treated with roofing felt, hydroisol or brizol.
Coatings. Special compositions that form a multilayer shell. They are applied from the outer part of the foundation. Coating can be based on asphalt, bitumen or tar.

“Major” waterproofing is carried out according to the following cycles:

Unstitch the seams between the blocks that are installed in the first, second and third rows.
Holes are drilled in the new foundation to half the thickness.
Next you need to install parkers adapted for injection.
A special polymer is poured between the blocks.
A pump is used for injection into the temporary structure.
Then the parkers are dismantled.
Seal up the holes.
Perform final, conventional waterproofing of the entire block foundation.

Waterproofing the foundation from FBS blocks ( belt type) on video:

Calculations and dimensions

This building material is made on vibrating tables, where supports are placed to ensure the specified density, flat surface and required dimensions. If the product violates the geometry, then it is possible to build a foundation, but the standards for seam thickness will be violated. And their value (according to the rules) does not exceed 5 millimeters, otherwise the waterproofing is compromised.

It is dense, smooth and high-quality surfaces that prevent cracking and premature destruction.

According to the state standard, there are established lengths for the FBS block (mm):

1180.

The width should vary from 300 to 600 millimeters. And the height is no more than 580 millimeters, but not less than 280.

For your information! Blocks with a height of 280 mm are not used in modern construction. For the base of the foundation, their load-bearing load is too weak.

For a profitable calculation, it is advisable to check everything in advance on a calculator.

But for clarity and visual representation, we present the following table to know the cost of the work:

Laying, installation: step-by-step instructions

You can’t do your work without:

polystyrene foam;
pipes;
mastic;
hydroglass insulation;
fittings;
shovels;
sand;
boards;
cement;
geotextiles.

The construction of the foundation for a real estate object is carried out in certain stages. Using the example of a private residential building, here’s how to do it right:

Marking the lines for installation and pre-treatment of the foundation area.
For this you need stakes and a regular light thread.
Where the marking lines intersect, it is necessary to knock out the reinforcing bars. According to their location, the plumb line (horizon) becomes extinct.
We dig trenches, having previously cleared their top fertile layer. The depth of any trench should be determined by the level of freezing.
Arranging the pillow. We fill the compacted trench with sand and gravel. The best bed for a clay area is a combination of sand plus crushed stone plus sand.
Moisturize the pillow and ram it.
On top of it you need to pour thin concrete layer(3 centimeters is enough). We are waiting for it to harden. Spilling with concrete is not done if a masonry mesh is provided over the cushion.
We begin installation. We lay the blocks from the points marked with reinforcing bars. Rods are usually placed at corners.
The initial first row is FBS flat block. It reduces shrinkage. The blocks must be secured with mortar. To do this, pour the mixture into the grooves and joints.
The first level must be checked to the horizon.

Each subsequent row requires dressing.
Let's give an analogy with brickwork- minimal differences. Vertical seams that are located in the center of the lower blocks must be overlapped by the element installed on top.
Angles deserve more attention. There must be overlap. Let's say the right side remains the outermost. The next layer or level should start from the left block.
We trace the thickness of the gaps between building material. And we fill it tightly with cement mortar, reinforcing the joints with fragments of brick or concrete.
Don't forget about the grillage. It must be dried for at least 4 weeks.

How to build a slab foundation from FBS blocks:

Estimate for the foundation

Even the smallest FBS block weighs at least 250 kilograms. You can't work with this material manually. Necessary lifting equipment. To more accurately calculate the estimate, labor costs and rental of special lifting equipment, there is the following table:

The most important thing is to know the mass of the material. Otherwise, there will be problems with delivery, loading and unloading. Blocks are transported by 10 ton or 20 ton trucks. Therefore, if I know the exact weight of the cargo, I can save money on transportation.

Let's summarize a simple list for calculating prices:

Order a truck crane.
Retail or wholesale cost of blocks.
Delivery and unloading at the construction site.
Installation and waterproofing works.

What owners and developers say

People who have mastered construction with such blocks give the following advantages:

Excellent installation characteristics;
Easy to attach at any time of the year;
Very solid foundation for brick, wooden, block or stone low-rise buildings.

The disadvantages are unanimously listed as:

High cost of materials. Prefabricated strip foundations made from FBS blocks on a turnkey basis cost from 6,900 per meter (price for the central region). The monolith will cost between 3-3.5 for the same unit.
High labor costs;
Equipment rental required. For your information, the work of loading equipment is measured in shifts. They will ask for at least 12 thousand per day of work.
The creation process requires a whole team of workers.

Results

A block foundation made of FBS is a design that is convenient when there is a need for quick construction. After all, it is allowed to assemble a base from already dried blocks at any time of the year.

The blocks are not afraid of cold, exposure to external factors and loads. But the problem is always in the seams, because improper installation and untreated connection elements will only lead to disastrous results.