In building a house, one of the most important elements is a high-quality foundation, since it is on this that the future construction will rest. Therefore, it must be built not only from high-quality materials, but also be installed correctly. Today, foundations made from FBS blocks are very popular, this is due not only to the high quality of the material, but also to the relatively affordable cost. Of course, many people wonder how to build a foundation from blocks.
Building a base from foundation blocks is quite simple and quick, and for more convenient work you can choose blocks of different sizes.
It is durable and highly reliable, but at the same time it is necessary to take into account the fact that these parameters are also ensured by proper installation.
The main advantage of such a foundation is that it can withstand both high and low temperatures, therefore, such a foundation is suitable for different climatic conditions. Installing a block foundation is a simple process, but it requires care and attention.
If you are planning on your own, it is advisable to use smaller block sizes, since an average block weighs up to 500 kg, so you will need additional lifting equipment. A wide selection of sizes and models of FBS blocks is another advantage; thanks to this assortment, you can build not only a block foundation, but also build walls, but wall blocks are required for their construction.
FBS is a ready-made material and you just need to buy boards of the appropriate size, so there is no need to grind or saw off anything.
The following tools and materials are needed:
- foundation blocks (preferably with ready-made holes);
- fittings;
- waterproofing material;
- concrete mixture;
- sand;
- shovel;
- concrete mixer;
- building level and hydraulic level;
- rope;
- wheelbarrows and containers for moving the solution;
- thin steel wire or nylon twine;
- Master OK;
- level;
- hammer;
- chisel;
- roulette;
- Construction crane.
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Dimensions of foundation blocks
Before building a foundation from blocks, you need to decide on the type of blocks for construction. Their sizes can vary significantly. What size blocks are needed depends on the purpose of the building. For example, block foundation under a house, especially a capital one, must withstand a colossal weight load. To do this, choose massive and wide blocks that can only be laid using a construction crane.
If the foundation is being built for a small building, for example, a garage, bathhouse, country house or outbuilding, you can use small blocks. A block foundation is built quite quickly, unlike a poured one. Almost immediately after its construction, you can begin laying walls.
In addition to their dimensions, the blocks also differ in density. It is better to use blocks with a density of 1500-1800 kg/m³.
It must be greater than the calculated thickness of the walls of the building.
The width of the blocks selected for construction is also taken into account. The blocks must fit freely into the trench.
The depth of the trench depends on the size of the structure and the composition of the soil.
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Installation of foundation blocks
It is better to install a FBS foundation in the warm season. The ideal time is summer.
Foundation blocks cannot be installed on a wet or damp surface; in unfavorable weather conditions, it is better to postpone construction. Before you start building a block foundation, you need to prepare the foundation, for this you need to install the axles, and then make a breakdown and dig a trench.
To transfer the axes, pull the axial threads and, using a body kit, transfer the intersection points to the bottom of the pit. It is worth thinking in advance about the cushion under the foundation - it should be made of sand, which must first be sifted and compacted. The thickness of the pillow is on average 5-10 cm, and its width should exceed 20-30 cm. This all applies to the construction of a strip foundation made of FBS.
If you plan to make a foundation from columnar blocks, you need to create special cabinets and pillows. The pillow must be in all holes and it is made according to a special pattern. The bottom of the pit needs to be flattened, then a cushion of crushed stone and sand must be made and carefully leveled. The resulting pillow can be covered with bitumen mastic. The main task is to make all the pits the same design and length. An ordinary rope will help you with this, which you need to stretch between the support points of the base.
The installation of the foundation must begin with blocks that serve as beacons; they are placed at corners, at intersections and on lintels. The correspondence of the direction and the project depends on how accurately the beacon blocks are installed. Then you need to move the pier upstairs, this needs to be done gradually, each time increasing the rows of stacked blocks.
Deviations are easily corrected with a crowbar, with the help of which the foundation blocks are moved to where they should be. Using a level, compliance with the drawings and correct placement of beacon blocks is checked, although any deviations are considered normal. If the level shows that the permissible standard has been exceeded, the block must be pulled out of the masonry and installed again.
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The principle of constructing a foundation from FBS
The main thing to pay attention to close attention, is the adhesion of the blocks, which must be thorough; the adhesion is done with the help of cement. Before laying, you need to prepare the solution, taking care in advance of its required consistency, since then you cannot add water to it, as this will affect the quality of the work.
Laying the blocks is similar to brickwork; horizontal deviations should not be more than 10 mm. For durability, the foundation is reinforced with a metal grid. Sealing seams and joints is a prerequisite when building a foundation from blocks, especially when building garages, basements, and basements.
To do this, the joints are filled with a special solution, which contains a waterproofing additive, which significantly increases its performance properties and. The thickness of the mortar depends on the size of the blocks. The gaps between the blocks are filled with reinforced concrete monolithic inserts. When you need to remember that the calculation is made based on the greatest height of the masonry, which should not be more than 5 blocks.
According to building standards and norms, small gaps can be made between concrete blocks to allow communications into the house: sewerage, electricity, and water supply. Indeed, today communications are carried out underground.
The work is completed with mandatory waterproofing of the foundation, installation of a reliable drainage system and high-quality blind area with the necessary slope from the main building. Drainage can be done using a clay castle or other available methods.
The strip foundation for a house is deservedly considered one of the most reliable, durable and load-resistant. But it takes quite a long time to build - a couple of days to excavate the earth, a couple to assemble the formwork, plus at least twenty to harden the concrete solution. To speed up the construction process, developers often replace it with prefabricated strip foundation from factory-made FBS blocks. This option is much easier to do, and the time required for installation and installation is much less.
What is a foundation made of FBS blocks?
The structure of the FBS base is a masonry of concrete blocks of various sizes on a sand bed. A reinforced reinforced concrete belt is sometimes installed between the rows and on top of them, but many builders do without it. Plus, the foundation concrete is protected by waterproofing, standard for all structures in the ground.
This is what they look like
FBS are often called “wall”, but this is fundamentally wrong. It is more correct to call them “solid” or “solid section”. In fact it's reinforced concrete products block type, intended for the construction exclusively of foundations and basement walls. Build wall partitions from them residential buildings and other buildings it is strictly forbidden. They are too heavy for that.
Types of block foundations
It is recommended to choose it only for areas with dry and low-heaving soils. But in fact, with proper calculation, such a support can be installed for any house and on any soil. FBS blocks made of reinforced concrete were originally developed to speed up and simplify construction. They can withstand considerable loads, you just need to select them correctly.
This is what a block base looks like
Buildings can be erected on a block foundation using all known building materials. There are no restrictions here. But for the same house made of SIP panels, which is distinguished by its light weight, it is better to choose cheaper screw piles. But in general, building rules and regulations allow walls made of brick, foam blocks, timber and logs to be erected on the base in question. Everything is at the discretion of the cottage owner.
Advantages and disadvantages of FBS blocks
Among the advantages are:
High speed of work;
There is no need to mix concrete or order a concrete truck;
Applicability on almost all types of soil;
High factory quality of concrete products;
No need for formwork.
Foundation blocks are brought to the construction site in a form completely ready for work. You just need to lay out the masonry from them. There is no need to wait for the concrete to set and gain strength. In terms of speed of construction, such a foundation for a private house can only be surpassed by a foundation on piles. It is generally difficult to compete with this option.
The disadvantages of a FBS base are as follows:
Expensive compared to conventional monolithic tape analogue;
Difficulties in cutting concrete products into pieces of the required size;
The need to use special equipment (crane or winch).
The choice of FBS device is often determined by minimizing time costs. Plus, its construction can be carried out even in winter. However, this comes at the cost of having to use lifting equipment. It is impossible to manually lay the products into the foundation; they are too heavy. As a result, this option is 15–25% more expensive than its analogue monolithic tape.
A crane is required for lifting
The main thing is that when compared with a monolith, the block type of foundations for buildings is somewhat inferior in terms of load-bearing capacity. And while it can easily withstand high vertical loads, there are serious problems with horizontal ones. If there is severe heaving, the block can simply be squeezed out of the supporting structure.
Installation instructions
The concrete foundation is built with your own hands according to all the instructions in four stages:
Design and selection of blocks.
Excavation work with filling a cushion of sand.
Installation (with or without reinforcement).
Waterproofing.
It is better to entrust the preparation of the project to a professional. This will allow you to obtain a foundation with the desired characteristics with a minimum cost of materials. FBS are available in different sizes. However, if they are too large, there will be extra expenses and loads on the ground. These concrete products must be selected according to the specific parameters of future walls. But usually for the bottom row they take a width of 400 mm, and for subsequent ones above - 300 mm.
All foundation blocks are divided into four subtypes:
FBS - solid privates.
FBP - with voids at the bottom to reduce loads on the soil.
FBV – with a cutout along the length for communications.
FL – trapezoidal slabs for the bottom row.
According to GOST, in the marking after these letters there are three numbers (length-width-height in decimeters) and the letters “T”, “P” or “S”, indicating the type of concrete used. In the first case, this is a “heavy” option made of cement, sand and crushed stone. In the second, there is a “porous” analogue, in which expanded clay concrete is used as a filler. And in the third it is a “silicate” product made with the addition of lime. The construction of foundations is always carried out using class “T”. Only they have the necessary load-bearing capabilities and are not afraid of moisture.
The ground stage is standard. It is necessary to dig a trench to a depth below the freezing point of the soil on the site. Then, at its bottom, a cushion compacted from sand 30–40 cm thick is made for the subsequent laying of FL slabs. Here it is important to do everything so that the sand layer is horizontally at the same level throughout the entire length of the pit. Otherwise, the base will most likely end up distorted.
Divide concrete foundation cutting a block into two parts of the required size is almost impossible. If voids remain in the masonry during installation, they are usually filled with bricks and the opening is plastered. FBS in a row from above are always installed offset; through vertical seams are unacceptable here. For masonry, standard cement mortar with a grade of at least M100 is used.
If reinforcement is required, then it is necessary to lay 2–5 rods in one layer on top of the already assembled row. In this case, the same technologies are used as when constructing a strip foundation. Only the reinforcing belt turns out to be single-row.
For waterproofing, roofing felt or other rolled equivalent is laid on top of the top rows. Even a soft roof is suitable for these purposes, but it costs more. The sides of the masonry are completely coated with mastic. The waterproofing layer should cover the concrete on all sides to minimize exposure to moisture. This way it will last much longer.
Before you start building a block foundation for a cottage, you need to plan everything carefully. It is necessary to provide a platform for unloading blocks and a place for a crane. This means that special equipment is not required to install supports for a pile foundation or pour a monolithic tape. There is no way to do this without special equipment.
Unloading
We prepare the solution and supply the first one with a tap
Lower the first one along the tensioned level
Place the second one on top of the first one
We adjust the position manually using a crowbar
We arrange all subsequent ones in the same way.
Block foundation and its application
According to the estimate, a block structure is slightly more expensive than a monolithic tape, but it is built much faster. In terms of load-bearing characteristics, they are largely similar, the main thing is that the FBS from the side is not subject to too strong an impact during heaving.
The only thing that can be done faster than the option under consideration is a foundation on screw piles. But the latter is often chosen only for light buildings, for the construction of the walls of which SIP panels or lightweight aerated concrete are used. A block base is more versatile. It is not difficult to build it yourself. The step-by-step instructions presented above will allow you to complete everything, avoiding possible beginner mistakes.
When calculating the cost of construction work, the cost of erecting foundations is a quarter of all costs of constructing a building. Each individual developer would not mind saving significant money on this part of the construction work, while maintaining a balance between price and quality, and in the case of foundations, also strength and reliability. For a technical and economic comparison, we can consider the cost of constructing popular types of foundation structures: monolithic concrete and prefabricated from FBS blocks.
Monolithic and prefabricated foundations: comparative characteristics
To make a comparison and draw a conclusion - which foundation is cheaper: monolithic or prefabricated from FSB blocks, you need to understand their structure and installation.
Monolithic concrete and prefabricated load-bearing structures can have two types of designs: strip and column. There are many differences in the construction of these types of foundation structures:
| Monolithic made of concrete | Prefabricated from FBS blocks | |
|---|---|---|
| Preparatory stage: excavation work | Required to be completed in full | |
| Financial costs for purchasing or renting removable formwork | Required in full | Not needed |
| Labor costs for installation and dismantling of formwork | Required, but can be reduced when using permanent formwork structures | Not needed |
| Time and season of work | Significant, including the period of strengthening of the concrete mixture and the warm season | Minimum |
Block structures are recommended for use in deep foundations.
Ready-made FBS significantly speeds up the laying of the underground part of the house, and therefore prefabricated foundations are cheaper than other types.
Comparison of monolithic and block foundations
In the comparison table you can see the main differences in the design and installation of foundations:
- The volume of excavation work for the installation of both types of load-bearing structures is approximately the same, with a slight advantage for a monolithic structure, which will require a little more space during reinforcement and installation of the formwork system.
- The price of precast reinforced concrete and ready-mixed concrete for a monolithic concrete mass is almost the same.
- Foundation blocks are laid on a layer of cement-sand mortar using a truck crane.
- Monolithic tape requires significantly more costs for the purchase of materials for formwork and reinforcement, the manufacture of reinforcement cages and their installation, the production of concrete (for small volumes) or purchase with delivery by a concrete truck - a mixer of ready-mixed concrete and laying the concrete mixture into the tape structure. Here we also need to add labor costs for compacting the concrete mixture by vibration and caring for the concrete for 3 to 7 days until it gains 70% strength.
- The cost of replacing a truck crane for unloading and installing a prefabricated block structure is about 12,000 rubles. The installation of FBS can be completed in a few days by a team of workers - installers in the amount of 3 people. If we carry out the simplest calculations, we can draw the following conclusions that the total cost of renting a truck crane, wages for installers and the purchase of cement mortar will be two or three times cheaper than performing similar work during the construction of a monolithic load-bearing structure.
Based on the listed conditions for the work and economic feasibility, we can make an unambiguous conclusion that a strip foundation made of FBS blocks will be better in all respects than a monolithic one .
Savings when installing a block structure
There are several additional opportunities to reduce the cost of constructing block structures. For example:
- When installing, use used blocks in good condition, the price of which will be several times lower than new ones.
- The possibility of constructing a block foundation in winter, when large seasonal discounts are offered for installation work.
- When constructing a prefabricated foundation, a combination of both FBS blocks and small-sized stones (cinder block or brick).
Such simple measures can significantly reduce the cost of constructing a prefabricated load-bearing foundation for a house.
Features of choice
Despite the comparative price indicators, one cannot be so clear about the choice: FBS or monolith. There are times when it is better to opt for a more expensive foundation design and at the same time ensure maximum reliability and strength of the entire structure.
It is known that any monolithic structure will be stronger than a prefabricated one made from individual fragments. This truth applies perfectly to foundation arrays. The reinforced concrete block itself is a single monolith, but a structure assembled from individual foundation blocks will not be completely intact and monolithic. This must be taken into account when choosing the type of supporting base.
If the building site has a soil foundation with possible horizontal displacement, the prefabricated foundation may end up in an extremely unstable position, which can lead to loss of integrity of the foundation mass.
If the soils on the site have unstable surface layers or the site is located on steep terrain or hills, it is better to give preference to a monolithic concrete foundation.
Construction of strip foundations on difficult terrain:
Criteria for choosing the type of foundation
The desire to save money when constructing load-bearing elements of the foundation is not always the main criterion for choosing a particular structure. There are basic situations for the construction of load-bearing structures:
- When constructing one-story brick, slag concrete, stone buildings or multi-story buildings with foam concrete walls, it is allowed to construct buried foundations from FBS blocks. More massive houses and structures are recommended to be installed on a monolithic solid foundation.
- If the foundation has a shallow structure, it is better to make it from monolithic concrete using a reinforcing metal frame. FBS blocks can be used in stable, strong soils.
- The combined technology of creating a foundation with a combination of laying FBS blocks and pouring a reinforcing monolithic concrete belt, which will simultaneously serve as the base of the building, has proven itself well.
You can make a foundation strip using any of the following methods. It is necessary to carefully weigh all the nuances of constructing foundation structures in each specific situation.
Arguments for choosing a monolithic strip foundation
There are times when there is no point in making a choice: a structure made of FBS or a monolith. There are conditions under which it is necessary to construct a monolithic concrete foundation in the form of a continuous strip:
- If the site has heaving soil foundations.
- There is a risk of increased seismicity in the construction area.
- Significant loads on the foundation, as a result of which the structure will be subject to bending moments.
Considering all these factors, we can conclude that the savings should be reasonable. The main thing for the foundation is strength, stability and reliability of the entire structure and ensuring the integrity of the entire structure.
It is difficult to say unequivocally which type of load-bearing base will be cheaper: monolith or FBS. To make an accurate comparison, it is recommended to link construction to the individual conditions of the site, the nature of the terrain and soil types.
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. Regular block for FBS foundation- this is a parallelepiped, the spitting image 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 - there are 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.
Choosing a foundation for building a house with a basement is 30% of construction costs. To reduce costs, a foundation made of FBS blocks, which ensures a long wear resistance life, would be relevant. To build a structure yourself, you need to rent special equipment, draw up a house project and dig a pit. Foundation blocks are an industrial technology that, if the sequence of measures is followed, can be successfully used in suburban, private and country construction.
What are FBS blocks?
The FBS foundation is made in the form of a reinforced concrete pad and block vertical walls. A foundation made independently from strong foundation blocks eliminates reinforcement, because concrete has the ability to compress.
Reinforced blocks - FBS concrete structures from which the foundation is made - have a number of advantages for owners of private or suburban plots.
The advantages of construction activities include:
- ease of installation work;
- high strength and frost resistance characteristics that the base will ultimately receive;
- low cost compared to the reliability of the base;
- selection of product parameters according to the configuration of the house or the depth of the fundamental structure.
The economic benefit of building a foundation from FBS blocks is manifested in the absence of costs and time for the construction of formwork or a frame made of reinforcement. The foundation can be created in any weather, and, moreover, there is no need to wait until the concrete dough gains strength.
The foundation, made of concrete foundation blocks, is made as a strip or has a columnar structure. The strip building can withstand the weight of a high-rise building, one-story house. Dimensions it has wall material, determined by the thickness of the ground wall, the type of soil, and the number of storeys of the building.
Columnar laying of foundation blocks is justified only on dense soils. If construction is carried out on marshy soils, support plates or piles are used.
Standard sizes of FBS products
FBS foundation is one of the types of blocks, the technical regulations for the production of which are specified in GOST 13579-78. Regulatory document considers materials, design characteristics and rules for transporting products. Solid blocks of increased strength are made from a concrete-based mixture with a density of 1.8 t/m3.
To build a block foundation, elements of several standard sizes are used:
- width from 30 to 60 cm in increments of 10 cm;
- length 9, 12 and 24 dm;
- 30 or 60 cm high.
FBS type blocks from which the foundation is made are fixed with a mounting loop or bent. A good storage option is to be placed on a wooden platform 3 cm thick. Laying a foundation from FBS blocks with your own hands
Algorithm of installation activities
Step-by-step instruction installation of block elements made of concrete consists of performing the following technological steps:
- Site analysis (detection of soil type, level of freezing, groundwater level).
- Excavation work (marking the territory, digging a pit).
- Organization of the pillow.
- Consecutive laying of blocks under a certain type of foundation.
- Performing waterproofing.
- Arrangement of thermal insulation.
- Backfilling of the base.
The correct foundation, made from FBS type blocks, implies not only the correct algorithm for how to lay concrete blocks. The measures require careful planning of the height of the walls, taking into account the existing basement floor and the depth of soil freezing.
Conducting terrain analysis
Taking into account the type of soil and groundwater level makes sense if a prefabricated strip concrete foundation running along the lines of the house needs to be organized on the site - the construction of FBS type blocks involves digging a trench.
To make a structure correctly, it is important to calculate its support. The elements are located 30 cm below the soil freezing level, which eliminates cracking of the material during frost heaving. If there is a basement, the depth of the structure is planned to be 20-30 cm below the floor surface.
Making a foundation from shallow FBS blocks is justified for light buildings made of wood, aerated concrete, polystyrene concrete, and SIP panels. The depth of the structure is determined by the type of soil. When working on dense soils, it is better to follow the standard placement of elements - 2.5 m. Monoliths without deepening are constructed only by construction specialists, since as a result of ignorance of the technology, the building can warp. Installation of FBS blocks using a crane to build the foundation
Carrying out excavation work
The foundation for a house made of concrete blocks provides for the correct marking of the territory. The site planning is carried out according to the design documentation and consists of two stages.
Marking the area for the pit
Professional guidance from specialists presents a clear markup algorithm:
Driving in stakes. They are located at a distance of 50–100 cm from the corners of the structure to prevent soil shedding.
Stretching the cord. It is placed according to the external walls, provides for the presence of a plinth and the width of the block.
Additional activities. If the building has a bay window or an entrance, then a prefabricated or strip type foundation created from FBS type blocks is marked with chalk or primer.
After all tasks are completed, the final result is checked against the project and adjusted.
Digging a pit
Excavation work is carried out taking into account existing communications, groundwater and soil. When the installation of the foundation is carried out in the basement, it involves laying slabs, and on the site there is weak soil, a foundation pit at a depth of 40 cm is justified. It is better to deepen the trench tape by 30 - 70 cm.
Digging a pit is done as follows:
The top layer of soil is removed to the selected depth.
For a deep pit, a barrier is installed.
Vertical surfaces are leveled and waterproofing is laid.
On loose soils, the walls are marked at an angle; when cutting through the aquifer, the trench expands and 3-5 ledges are made, depending on the type of soil.
The verticality of the walls is periodically monitored.
Further tasks include laying geotextiles and forming a bed based on gravel and sand.
Which Additional requirements to digging a hole? Carrying out work in the dry season to prevent soil erosion.
Pillow organization
The foundation for a block house, depending on the soil, is laid on reinforced concrete slabs, sand, gravel mixture or crushed stone with medium fractions.
Reinforced concrete option
You can make a heavy strip foundation, working with elements made of concrete blocks, by laying reinforced concrete products as a cushion. Activities are subject to the following algorithm:
Laying a sand base with a thickness of 0.3 - 0.5 (based on the type of soil).
Medium or coarse sand is selected for the substrate, since it shrinks less and the foundation for a house made of blocks does not deform.
Features of sand-based pillows
A sand cushion is useful to create a prefabricated foundation made of blocks. The substrate is characterized by ease of implementation and low cost. A prefabricated strong foundation made of FBS concrete blocks will distribute the load of the building onto the ground.
Application of sand and gravel cushion
The structure, made from a mixture of gravel and medium-sized sand, is distinguished by good load-bearing capacity and ease of implementation. In comparison with a sand foundation, the laid frame - a strong strip foundation, massive of dense concrete blocks - will have a high cost. The advantage of using sand and gravel is the good density of the materials - they can withstand the weight of a high-rise building.
Pouring a concrete pad
Option suitable for buildings with increased load. Step-by-step instructions for reinforcing and pouring concrete dough:
The formwork is being installed. Use the materials you used to decorate your site - plywood, OSB, boards with waterproofing.
A reinforcing frame is made based on a mesh belt and profile rods with vertical jumpers.
The concrete mixture is poured in one go.
The composition is laid along the upper side of the formwork frame. Foundation made of FBS blocks - advantages and structural characteristics of the base
Block laying technology
The construction of a FBS foundation requires preliminary preparation of drawings. A simple diagram will allow you to understand how to lay the first row of blocks on the foundation, and the next one after it. Bandaging must be performed with a displacement of the elements by 25 cm.
Nuances that are important to consider
An algorithm developed by specialists will tell you how to make a foundation out of blocks.
According to the rules:
- the optimal length of products should be 2.4 m - this reduces the number of seams;
- coupling with reinforced concrete pads by filling voids with concrete mixture is required;
- installation of ventilation ducts with a total area of 0.004 units of the basement space.
At weak ground the first row is reinforced with a monolithic reinforced concrete belt.
Technological sequence of laying
For the rigidity of the main structure, a foundation placed on prefabricated blocks laid by hand is relevant. The measures are carried out taking into account the location of the corners on the same line, the presence of elements near the communication holes and the tightness of all products.
Correctly making a foundation from FBS blocks means following a step-by-step methodology:
When placing a foundation made of durable FBS blocks on the ground, learn how to properly lay blocks on concrete dough. Work in a similar way to brickwork.
Performing a T-shaped dressing with an overlap in? height of the element (dense soils) and to the full height (soils subject to compression).
Filling the solution only with a shovel and then leveling it.
Filling vertical seams after making a row of blocks with your own hands.
Verticality control with beacons (deviation angle of 2-3 degrees is allowed).
Formation of technological openings, slightly larger than those indicated in the project for quick fastening of anchors or bricks.
The last row of the structure is widened by installing 40 cm elements on 60 cm blocks - this increases the spatial rigidity of the house. The foundation from FBS blocks is the basis of construction
Final stage of events
When planning how to properly build a foundation on strong blocks, working with your own hands, do not forget about waterproofing and backfilling measures. Manipulations are carried out on any soil and include the following:
waterproofing. The made block layer is treated with roofing material, bitumen, and liquid rubber backfill. The constructed monolith dries for several days, after which it is covered with sand with fine fractions and compacted.
The final manipulations consist of organizing drainage and blind areas.
A foundation made of concrete blocks is a structure that, if you become familiar with the algorithm in detail, will not be costly in terms of time and money.
You can speed up the construction of a building by using a shallow foundation made of FBS blocks installed in one row. An additional benefit is the reduction in house construction costs.
FBS is optimally suited as a strip foundation.
A prefabricated structure is indispensable if you plan to build a basement or basement floor.
Main stages of installation.
The prefabricated structure has many advantages and only one drawback - the base cannot withstand strong mechanical loads and cannot compensate for the looseness of the soil in case of subsidence or tilting.
The installation of slabs is carried out taking into account the characteristics of the building under construction and the soil and is carried out in several stages:
Manufacturing of a seismic belt. To reduce the likelihood of cracking of the foundation, a cushion is first made, similar to a tape and completely repeating the contours of the load-bearing walls of the future house.
Concrete is poured to a height of 20-30 cm and a width 3 cm greater than the dimensions of the slabs, with mandatory reinforcement. The blocks are laid after the pillow has dried, after 1-2 weeks, the period depends on weather conditions.
Laying the base. It will be enough to place the slabs in one layer on top of the concrete pad.
Some installation teams tie a reinforcing layer on top of the slabs for greater strength.
Walling. Bricks and foam blocks are laid immediately after completion of the FBS installation work.
Manufacturing takes 1-3 weeks if pouring a concrete belt is used. Without it, the construction of walls begins within 3 days from the start of repair work.
Things to remember.
When arranging the foundation, you have to take into account many nuances and perform complex calculations. Often those who build a house with their own hands make simple mistakes that affect the further operation of the building:
Communications. Sewerage and water supply are laid in blocks. The location and depth of the pipes are calculated taking into account possible future settlement.
Additional reinforcement. The decision on whether a seismic belt is needed is made after conducting a topography of the site. In most cases, when laying FBS in one row, additional reinforcement of the blocks is necessary.
Practice shows that only a qualified installation team can take into account these and other features and make a block foundation.
JonikS said:
drilled a meter for piles (piles every 2 m),
For what? Where do these ideas come from?
if you are making a belt buried in the ground, then why use piles?
JonikS said:
soil loam
Determining soil characteristics or ordering geological surveys
JonikS said:
Is it possible to use fiberglass reinforcement?
only if you are not interested in the result
JonikS said:
Such a foundation is suitable for a house made of foam blocks of 1.5 floors
Minimal foundation. Choice of foundation.
JonikS said:
There are not enough FBS blocks for the entire foundation, is it possible to fill the gaps with bricks or fill them with concrete, or buy additional blocks?
Monolith or blocks. There is no need for bricks in the ground.
Durable and reliable FBS blocks attract builders due to the durability and attractive price of block materials. Their direct purpose is the construction of walls of underground premises while simultaneously performing the tasks of the foundation.
- Foundation construction technology step by step
- Common Mistakes
- Adviсe
The value of these materials is explained by the following advantages:
- high speed and ease of installation, which is ensured by the elementary geometric shape of the products;
- minimal labor intensity compared to pouring;
- the ability to carry out work regardless of the time of year, since the technology for creating FBS guarantees high quality material and the absence of defects resulting from temperature changes;
- the ability to lay blocks with their own hands for people, even without special skills, without first taking into account the loads and characteristics of the building.
The main stages of constructing a foundation from FBS
One calculation will have to be made: you need to find out the quantitative need for the material. Knowing the perimeter, height and thickness, you can calculate the total volume of the masonry, after which this figure is divided by the cubic capacity of one element. It is more advisable to use small-sized products, since they are much more convenient to install due to their lighter weight than large ones.
Need or detailed diagram, or a drawing where information about the parameters will be reflected:
- soil type;
- depth of soil water and soil freezing;
- dimensions of the base in accordance with the size of the building;
- plan of the basement with reference to the input of utility communications.
When purchasing FBS, you can take a special block with ready-made holes. If the task is to make a shallow strip foundation for the construction of outbuildings such as a bathhouse or garage, then it is enough to use one row, in general there can be up to 5 of them.
Often blocks are produced for a specific type and are called that way: for a strip base, columnar, columnar.
Step-by-step instructions include:
- site preparation, which consists of marking, digging and clearing the trench of debris;
- work on organizing a sand cushion;
- creating a base: either from a monolithic concrete screed, or from the flat slabs themselves;
- laying the foundation blocks themselves.
Sometimes the process ends with waterproofing or insulation.
Let's look at the stages:
1. When preparing the site, the surface is leveled, vegetation and large stones are removed.
2. Arrangement of the pillow. First, 10-15 cm of sand layer or crushed stone with sand is poured in a ratio of 10:5. If the soil is clayey, then the sole is made of 3 layers, 60 cm thick, laying the middle with coarse filler. This is followed by the processes of abundant moistening and compaction.
3. The foundation for the foundation is created from the thinnest layer of concrete of 20–30 mm on compacted sand. But first you need to lay the masonry mesh, and then slowly pour the solution onto it, piercing it with fittings to remove air. In case of hot weather, it is moistened to prevent cracking.
4. Blocks are placed using lifting equipment and in the presence of 2-3 assistants supervising correct installation elements. But first you need to prepare a cement composition, the density of which resembles thick sour cream, in such a quantity that there are 10-15 liters for each unit of base. Or purchase a special construction adhesive: it is preferable, as it speeds up the process, but is more expensive.
5. All contacting surfaces of the FBS are coated with the fastening solution: both vertical and horizontal. The sequence of laying the foundation from FBS blocks:
- Installation begins with elements along the extreme axes, at the corners of the future structure, which are connected to each other to trace the perimeter.
- The first row is made of dimensional or flatter products. This ensures guaranteed stability.
- The blocks are laid out strictly according to the level, filling the seams between them with the prepared composition.
- The direction of each row is opposite to the previous one. That is, even rows, for example, go from north to south, and odd rows go from south to north. The elements are mounted according to the same scheme as brickwork, with offset.
- After the foundation for the external walls is made, they begin to build the foundation for the internal ones.
- The vertical seams of the upper rows fall in the middle of the lower ones. Corner elements are placed with overlap.
- A solution 1.5 cm thick is applied between the rows.
Common mistakes when laying blocks
This information is aimed primarily at beginners in order to focus their attention in order to avoid dangerous situations.
| Errors | What to do to prevent them |
| Poor organization of the sand cushion | Compaction of the concrete pad must be done carefully, layer by layer, using river sand and wetting it |
| Formation of voids and holes not provided for in the design | Such gaps lead to destruction of the product. Therefore, these cracks are filled with concrete or brick without disturbing the integrity of the block, and a solution is applied on top. But first of all, you need to strictly follow the instructions for constructing structures |
| Exceeding the horizontal angle by more than 2°, and vertically by 3° | This must be monitored throughout the entire work using special beacons, cords and levels |
| Construction of the foundation without taking into account future utility networks | This issue is resolved at the stage of purchasing special blocks for this purpose. |
Waterproofing should not be neglected, which will protect the concrete from destruction under the influence of incoming moisture. For this protection, a roofing material coating or thorough bitumen coating of the base on all sides is used. For insulation, extruded polystyrene foam or polystyrene foam is selected, which is glued on the outside and inside.
The technology discussed above is most often used for shallow foundations made of FBS. If material needs to be placed in heaving soil, it will be correct to do the installation according to this scheme:
- a trench is dug to 0.4 m;
- a cushion of hard crushed stone and sand 0.3 m thick is laid on the bottom;
- the reinforcement is installed and a solution 0.1 m high is poured on top;
- after the screed hardens, blocks coated with bitumen are placed;
- another reinforcing concrete frame is made on top.
Sometimes, in order to reduce the cost of constructing light structures without a basement and under the necessary soil conditions, an “intermittent” foundation is allowed. Its essence is to place the FBS at a distance of 0.7 m from each other, but no more. Material savings reach 20%. But this scheme is only suitable for one- and two-story buildings.