Even before the advent of high-strength insulation materials, solid slab foundations were considered an effective means of compensating for seasonal (frost heaving) and non-seasonal soil movements. Being “floating”, they maintained the relative position of all elements of building structures relative to each other, even when houses fell into areas of small landslides. An original engineering innovation that combined the solution to energy efficiency problems was the so-called USP foundation, the technology of which came to us from Sweden and Germany. This article describes the design and operational features of the insulated Swedish stove (as the abbreviation “USHP” stands for).

About 10 years ago, the first domestic enthusiasts, developers, used standard projects from this particular company. According to Dorocell, the optimal energy-efficient foundation for low-rise housing construction is a high-quality monolithic concrete slab with stiffeners, external thermal insulation and built-in heating.

Scheme of the technology for installing an insulated Swedish USHP plate using TechnoNIKOL materials

Thermal insulation, representing a kind of “trough” for pouring concrete, serves as a natural permanent formwork.

Here is a detailed overview of the foundation of an insulated Swedish slab:

1. Formwork made of polystyrene PSB-S is assembled on a compacted sand and crushed stone bedding. At the bottom of the backfill bed, slopes were made and a drainage pipe was installed.
2. Formwork 400 mm high consists of slabs 100 mm thick and forms rectangular grooves with a cross-section of 400×200 along the perimeter to form stiffeners and a bed for pouring the main slab 100 mm thick.
3. Reinforcement of the ribs is carried out in two belts with a profile of variable section with a diameter of 8 - 12 mm. Reinforcement of the floor slab is carried out using a welded mesh 150x150 mm.
4. The heating system pipelines are embedded in the floor slab. The floor slab is reinforced using a 150×150 mm welded mesh laid on top of the heated floor pipes.
5. In addition to the heated floor, other communications are also poured with concrete - water supply, sewerage, electrical wiring in the rooms.
6. Insulation of the blind area is carried out along the perimeter of the foundation with 70 mm PSB-S slabs adjacent to the polystyrene formwork from the outside at the depth of its contact with the bedding.

Thermal insulation skirt around the foundation slab protects against freezing

The described scheme corresponds to the load generated by a two-story house with load-bearing walls made of cellular concrete, as well as climatic conditions with a frost index of 4000 - 8000. An increase in load requires an increase in the cross-section of the stiffeners, and a more severe temperature regime requires the addition of one or two additional layers of insulation.

There is an alternative technology for installing an insulated foundation: UFF - insulated Finnish slab. An overview and features of this type of foundation are described in

The best video about USP technology

Pros and cons of the Swedish stove

The most important thing is that as a result of installing the foundation according to the warm Swedish stove scheme, the developer receives a solution to a whole range of issues:

• effective drainage,
• anti-frost protection,
• energy saving,
• heating,
• comfortable microclimate,
• laying communications,
• as well as obtaining a floor surface for finishing coatings.

Other benefits of the scheme include:

• For frame houses, USHP compensates for their main drawback - the low heat capacity of the walls. A massive insulated foundation takes on the function of a backup heat accumulator.
• Price. Despite the fact that the Swedish scheme is not a cheap pleasure, it includes not only the zero cycle, but a whole set of stages. Performing these works separately costs significantly more in total.
• Deadlines. When the work is carried out by a team of qualified specialists, everything will take, on average, about a week.
• Versatility. The technology is suitable for most soils and climatic zones of the Russian Federation.
• Indispensable in the construction of “passive house” class buildings.

Disadvantages of a foundation based on a warm Swedish stove:

• Conditional (psychological) disadvantage: low base. In houses with a regular foundation, a high base is necessary to ensure normal humidity in the rooms. Until now, many of our compatriots tend to consider the height of the basement as one of the guarantees of housing quality.
• Maintainability of communications. Since the floor slab is a stressed structure, it is extremely undesirable to violate its integrity to repair bricked up pipelines. On the other hand, there are other installation methods and technical solutions that compensate for the shortcomings of the circuit. But all these measures lead to an increase in costs.
• Requires highly qualified performers. Not every team will take on the turnkey delivery of the USP.
• It requires significant one-time capital expenditures, therefore it is not suitable for developers who expect construction in small (in terms of money) stages.
• Not suitable for peaty soils and other soils with low bearing capacity, as well as areas with large slopes.

Technology development: methods, materials, components

To date, more than 1.5 million houses have been built under the USP scheme in Germany and the Scandinavian countries. In Northern Europe technology insulated monolithic slab foundation received generally accepted status and is reflected in EU building standards. In the USA, complete external insulation of slab foundations is not widespread, since 90% of the country has a frost index of no more than 3000. However, USP has also found application there: first of all, in the construction of “passive houses”.

Over the past 10 years, project developers have given greater preference to extruded polystyrene foam (EPS) as a material that provides more uniform shrinkage of foundations and maintains thermal insulation properties regardless of time and operating conditions. The stresses in concrete arising during the operation of shallow slab foundations were studied in detail. Based on their results, builders abandoned the idea of ​​using insulation materials with different ultimate strengths (previously it was assumed that in order to equalize shrinkage under the floor slab, it was necessary to use less strong slabs than under the stiffeners). It has been proven that the most dangerous stress concentrators in a slab can occur at the junction of different types of heat insulation.

Manufacturers of extruded polystyrene foam began to produce materials and components specialized for the installation of USP.

For example, Dorocell itself currently produces a complete set of “designer” parts for permanent formwork made of EPS. The company's calling card is blocks with built-in guides for fittings. Some brands pay increased attention to the aesthetic properties of the components: the sides of the formwork are molded in the form of plinths of a traditional variable section.

If we talk about the domestic market, then there are 2 brands on the market: TechnoNIKOL and Penoplex. Both companies produce EPS of European quality level for slab foundations built using USHP technology. I would like to dwell in more detail on the specialized series TECHNONICOL CARBON ECO SP. In addition to the basic slab formats, it includes L-shaped profiles for quick installation of sides. In addition to the cross-section, these elements are interesting in that CSP (cement particle boards) are fixed to their base parts on the outside. DSPs allow you to apply decorative plaster without additional preparatory stages. Thus, installation of USP using TechnoNIKOL components is currently the most convenient.

Algorithm for installing an insulated slab foundation

For a full cycle of work on arranging the USP, you will need the following basic materials:

• Geotextiles;
• 100 mm EPS slabs for formwork and 70 mm for insulating the blind area;
• fittings Ø12; welded mesh 150×150;
• Concrete grade not lower than M350 with the necessary additives, taking into account the pouring time and air temperature, anti-capillary crushed stone, coarse sand;
• Pipes of the PEX or P-PE type for a pressure of at least 6 bar at a coolant temperature of up to +95°C, as well as a protective corrugation;
• 1"" collectors (for a house with an area of ​​no more than 250 sq. m., in most cases, 2 pieces are needed);
• Shut-off valves consisting of Eurocone compression fittings, 1" ball valves and a system crimping unit;
• Special fasteners consisting of disc-shaped dowels, studded plates, FS-30/40 clamps, double-sided tape.

After completing geological surveys, strength calculations and purchasing materials, the future foundation is marked. Based on the addition of 0.3 - 0.5 m to the edge of the insulated blind area, the perimeter is determined. The axes of the internal load-bearing walls are marked, as well as the points and directions for laying communications. Further work is carried out as follows:

1. Removing fertile soil;

   

2. Laying geotextiles along the bottom with overlapping joints of at least 15 cm;
3. Layer-by-layer backfilling with crushed stone and sand is carried out. Each layer of 10 - 15 cm is compacted with a vibrating plate with added water for greater compaction;

   

4. Laying communications - water supply, sewerage, power cables, ground loop, drainage system. When laying sewer lines, ensure slopes. When arranging drainage, in addition to observing slopes, provide drainage wells. Check the operation of the slopes with water.

   

5. Backfill drainage and sewer trenches and check the overall plane of the backfill pad.

   

6. Start assembling the insulating formwork. If L-shaped profiles are not used, then you will need to do a significant amount of work. First, the slabs are glued end to end at an angle of 90° using a special glue. For additional fastening, disc dowels and plastic fastening corner elements are used. Secondly, the resulting sides need to be fixed from the outside with plywood or boards, supporting them with slats.

   

7. Starting from the second or third layer of polystyrene, niches for stiffeners are formed during installation. The slabs are laid in a horizontal plane “in a staggered manner”, with the joint line offset.
8. If necessary, a vapor barrier layer is laid on top of the last layer of EPS.

   

9. Let's start reinforcing the stiffeners. Reinforcement is provided by four longitudinal reinforcement bars Ø 10 - 12 mm, forming the upper and lower chords. The load-bearing frames are connected using special clamps outside the formwork. The finished power units are installed in the grooves and secured using FS clamps.
10. Using the same clamps, a 150x150 mesh is mounted for the floor slab (rod diameter 6 - 10 mm).
11. Heated floor pipes are installed over the laid mesh and secured with nylon clamps. When crossing stiffeners and doorways, pipes must be protected with corrugations.

    

12. After installing all the heated floor circuits, they are connected to the collector. The places where pipes rise to the collector are protected by corrugation.
13. Each circuit is filled with coolant separately. Filling is carried out through the manifold until all air is displaced from the system. Then leak tests are carried out. After testing, it is necessary to crimp all connectors of the system.

    

14. Before concreting, it is necessary to check the structure. The check consists of control measurements of the formwork, inspection of the reinforcement, clearing the site of debris, protecting communication terminals from concrete, as well as checking the fixation of these terminals on the formwork. At the end of the preparation, the entire initial situation with the location of communications should be captured in detailed photographs and an internal inspection report of the formwork and engineering systems should be signed.
15. We select a concrete supplier and order him a mixture with the properties required by the project.
16. On the day of concreting, large equipment (mixer, concrete pump) is placed, the mixture is accepted for quality, the mixture is laid and maintained. Laying work is carried out in accordance with the standard for carrying out this type of work in compliance with working methods and time intervals. During installation, it is necessary to carefully monitor the flow of mortar under the reinforcement elements. The surface is leveled using vibrating slats. Vibration processing of the incoming mixture is provided in the stiffeners. In order to ensure the required dehydration regime, the concrete is covered with polyethylene film.

    

17. In the future, it is necessary to monitor the progress of dehydration and check the surface for a strength gain of 15 kgf/cm2. This indicator makes it possible to carry out other construction work at the site.

    

18. While the concrete is gaining strength, you can organize cleaning of the area and lining the outer surface of the base with finishing material.
19. After covering the base, it is necessary to organize a blind area. It is recommended to lay a drainage membrane on top of the blind area slabs. At the end of the work, the blind area is backfilled.

What stages of installing an insulated Swedish stove are acceptable and advisable to do yourself? If you do not have experience in carrying out the types of work described, then you can only recommend paragraphs for doing it yourself. 2; 6; 7; 8; 10; 14; 15; 17; 18; 19.

Persons who have the necessary skills, but work alone at their site, are allowed to carry out all types of work except concreting. An exception may be objects with a small area (up to 30 - 40 sq. m.).

At the initial stage of building construction, the foundation is laid. The foundation is subject to not only requirements to ensure the stability and durability of the building. It is important to reduce the cost of maintaining a comfortable room temperature due to the energy efficiency of the foundation structure. The insulated Swedish stove meets the specified criteria. It represents a solid reinforced concrete base that combines heated floors and utilities. Let us dwell on the design features and manufacturing technology.

Swedish slab foundation - purpose and scope

When thinking about the design of the foundation, most developers choose between strip, slab and pile structures. However, modern construction methods and innovative technologies make it possible to build a fundamentally new foundation. The Swedish slab is a shallow slab-type base made of concrete and reinforced with a reinforcement frame.

The Swedish foundation slab is a multi-layer structure. The construction in the form of a kind of sandwich allows you to speed up the construction cycle and solve a number of important problems:

Insulated Swedish slab (USP) - a modern and complex foundation design

• effectively insulate a monolithic foundation slab;
• arrange electrical cables, water pipes and sewer networks;
• prevent possible deformation of the base;
• maintain a comfortable room temperature by heating the floor;
• create a reliable base for laying decorative coverings.

A foundation slab with an integrated heating system is used for the construction of buildings on soils containing an increased concentration of sand particles, peat, and clay inclusions.

The design features and safety margin of a monolithic slab allow the construction of buildings of various types:

• log buildings;
• timber houses;
• frame buildings;
• panel houses;
• buildings made of bricks and porous concrete blocks.

The use of lightweight building materials makes it possible to erect buildings on a warm slab, the maximum number of floors of which is 3 floors. The Swedish slab is constructed after performing thermal engineering calculations, as well as design measures that take into account the load from the mass of the structure and the characteristics of the soil. It is important to choose the right building materials from which the walls, ceiling and floor are built. Electrical appliances together with internal communications are placed in accordance with the design documentation.

The main feature of this technology is that the entire foundation of the house is based on a layer of insulation (under the slab)

A warm foundation in the form of a slab is a complex structure, the construction of which is associated with increased costs. When deciding to build an insulated Swedish USHP slab using modern insulation, you should carefully evaluate all factors.

Multilayer construction is preferred in certain cases:

• when the construction site is located on problematic soils;
• during the construction of buildings with a box height of up to 10 m;
• when located near the zero groundwater level.

The decision to use an insulated Swedish slab as the foundation of a building is made individually after analyzing all factors.

Insulated Swedish stove - main advantages and weaknesses

The experience of using slab foundations in Sweden confirms that the Swedish warm slab combines innovative technical solutions aimed at energy saving. USP plate is widely used abroad and is gradually being introduced by our builders.

A characteristic feature of the Swedish slab technology is that Swedish manufacturers have already calculated all sorts of foundation construction options for this technology, depending on the type of soil.

The number of supporters of the new fundamental framework is constantly increasing due to its advantages:

• reduced duration of construction activities. The necessary utilities are laid simultaneously with the construction of the foundation;
• no unevenness on the concrete surface. Sanding the subfloor at the final stage of construction allows you to lay the floor covering on the concrete;
• preventing soil deformation under the foundation during freezing. A thermally insulated foundation minimizes the likelihood of soil deformation at subzero temperatures;
• the possibility of constructing an insulated base without the use of special equipment. Eliminating the need to use lifting devices reduces costs;
• innovative design of a multi-layer foundation. The heating circuit lines are placed in a concrete base, which avoids additional measures for their installation;
• the possibility of using USHP slabs to build houses on various soils. A solid foundation, in the construction of which reinforcement is used, allows the construction of objects on problematic soils;
• uniform increase in the temperature of the concrete base when heated. Ensures compliance with the technology for laying heating lines;
• maintaining a comfortable temperature. Thanks to the increased efficiency of the heating system and convective heat exchange processes, it is easy to maintain the required microclimate;
• decrease in air humidity. Regardless of the moisture concentration in the soil, the formation of dampness, mold and mildew indoors is excluded.

The “Swedish slab” technology combines the construction of an insulated monolithic foundation slab and the possibility of laying communications, including a water floor heating system

The Swedish hot plate does not crack under the influence of forces from the weight of the building and reliably insulates the room. Along with the advantages, the USHP plate has the following disadvantages:

• the complexity of carrying out repair activities associated with the difficulty of access to concreted communications;
• insufficiently high durability of the Swedish stove, due to the limited service life of the heat insulator;
• impossibility of arranging a basement;
• the need for qualified performance of thermal engineering calculations, since the thickness of the Swedish plate depends on the characteristics and size of the insulation;
• increased estimated cost of work associated with performing special thermal and strength calculations;
• the impossibility of arranging a thermally insulated foundation slab in conditions of inclined terrain.

Despite these disadvantages, such a slab is superior to traditional types of foundations in many respects.

Swedish stove - device diagram and technology specifics

An insulated slab is a type of slab foundation made in the form of a sandwich.

The construction of the foundation and the laying of communications are carried out during one technological operation, which allows reducing construction time

The multilayer design includes the following levels:

• communication It includes electrical cables, water pipes and sewer lines;
• insulating. Includes sheet expanded polystyrene in extruded form, which thermally insulates the foundation base;
• enhancing. Made of reinforcing steel with a cross-section of 12-14 mm, preventing cracking of the heated floor;
• heating. It consists of a system of water mains designed to circulate coolant;
• carrier. It is a concrete base that protects the heating lines and serves as the basis for the construction of the building.

Creating a foundation using Swedish technology involves a sequence of work in accordance with the requirements of the technological process. The entire foundation is immersed to a small depth in the soil relative to the zero level. Thanks to this feature, the possibility of frost heaving of the soil at high humidity is eliminated.

In what sequence is the Swedish stove installed?

Compliance with the construction algorithm of the Swedish slab affects the strength properties of the base and energy-saving characteristics. The general scope of work includes:

The soil under the insulated slab does not freeze, which minimizes the risk of frost heaving problems in foundation soils

1. Construction of the pit.
2. Installation of drainage pipes.
3. Laying communications.
4. Laying insulation.
5. Warm floor assembly.
6. Concreting.

Let's consider the main features of the stages.

Marking the area

This stage of work involves transferring the foundation project to local conditions. Before marking begins, it is important to carry out geodetic surveys aimed at determining the nature of the soil and the depth of the aquifers.

During the marking process, the following are determined:

• foundation contours;
• ways to connect utilities.

After marking, it is important to protect the site from precipitation by installing a storm drain.

We carry out excavation work

Earthworks include the following work:

To ensure normal operation of the insulated Swedish slab (USP) and prevent frost heaving, it is necessary to provide a groundwater drainage system

1. Clearing the construction site of construction debris and vegetation.
2. Extraction of fertile soil layer to a depth of 0.4-0.5 m.
3. Formation of a compacted sand layer with a thickness of 30 cm.
4. Extraction of soil around the perimeter of the pit for drainage lines.
5. Filling clay at the bottom of the pits, moistening and compacting the clay layer.

After completing the excavation work, proceed to the next stage.

Setting up a drainage system

Sequencing:

1. Lay down geotextiles.
2. Pour in crushed stone.
3. Compact the crushed stone.
4. Lay drainage pipes.
5. Fill in a layer of crushed stone.

After laying all layers, cover the bedding with geotextile fabric.

We lay utility lines

When performing work, observe the following sequence:

All necessary communications must be laid under the slab in advance.

1. Install communications.
2. Add a layer of sand.
3. Compact the sand bedding.

After installation, it is important to check the correct connection of utility networks.

We select insulation and install it

When choosing a heat insulator, give preference to insulation with reduced thermal conductivity.

It is advisable to use extruded polystyrene foam, which has the following advantages:

• resistance to the development of microorganisms;
• environmental cleanliness;
• resistance to moisture.

Lay polystyrene foam in two layers with overlapping sheets of 40-50 cm. Use special fasteners for fixation.

We lay the reinforcing mesh and install the heated floor

When performing reinforcement, pay attention to the following points:

• use tying wire to connect the reinforcement;
• lay the reinforcing mesh in two tiers;
• ensure a distance to the heat insulator of 30-40 mm.

Install heating lines taking into account the layout. Use plastic supports for laying pipes.

Higher thermal power of underfloor heating is achieved by denser pipe laying

When laying heating lines, pay attention to the following points:

• ensuring a distance of 100 mm between heating lines;
• making a distance from external walls of 150-200 mm;
• correct pipe laying according to the developed diagram.

After laying the lines, check the tightness of the system with compressed air.

We install the formwork

Installation of a Swedish slab requires the construction of formwork around the perimeter of the foundation. For formwork, plywood or board panels reinforced with supports are used. The inner surface of the formwork structure is lined with polystyrene sheets. They provide thermal insulation of the foundation from the end part.

We pour the concrete mass

When concreting, observe the following requirements:

• pour concrete in a 10-centimeter layer;
• fill at intervals of no more than an hour;
• use a vibrator or slab to compact the concrete.

Moisten the surface of the concrete during the hardening process, cover the base with polyethylene to protect it from moisture evaporation.

The Swedish slab foundation ensures the stability of buildings and has increased energy-saving properties. will ensure reliable protection of the base from moisture. According to the Swedish method, monolithic can also be poured. To build a house on an insulated base, aerated concrete blocks and slabs are suitable. When building a house, to reduce heat loss, you should pay attention to the layout of the floor slabs. An important point is sealing the seams on the ceiling between the slabs.

In contact with

Classmates

Insulated Swedish stove (USP) is a variety, the peculiarity of which is the presence of a cutoff - a layer of insulation between the soil and concrete.

Without changing the basic qualities common to slab bases, such a cutoff rearranges the heat transfer of the slab to be transferred upward into the living space. As a result, one more thing is added to the general beneficial properties - heat is not wasted on heating the soil under the slab, which allows you to significantly save on heating your home while maintaining consistently high home comfort.

Although diffusion as a technology is relatively recent, some conclusions regarding the qualities of such a foundation can be drawn unambiguously:

1. Possibility of construction in areas with unfavorable geological conditions. This refers to the presence of groundwater, pronounced heaving processes, seasonal soil movements, and the danger of flooding of the site, which is very important in the conditions of most regions of Russia.

Important! An insulated Swedish stove is a solution for those who are forced to build a house on “difficult” soil.

2. There is no need to dig a deep pit, you don’t even need to go deep below the soil freezing level. It is enough to remove the top fertile layer and plan the area.

3. Warm floor provides a powerful thermal cushion, which does not waste energy on heating the ground and effectively transfers heat to the house. This allows reduce heating costs, which is very important for areas with low temperatures.

4. All communications are built into the slab, which does not require subsequent gating and insertion of pipes into the house. In general, this circumstance is both an advantage and a disadvantage of the USHP foundation at the same time, since along with ease of use there is a danger of failure, which will entail complex repair work and the need to break the slab. Such an operation cannot but affect foundation strength.

5. Completion means the ground floor is level and ready for flooring to be installed. Thus, the foundation simultaneously plays the role of a ceiling.

6. Effective waterproofing and thermal insulation reliably protect the Swedish stove, significantly increasing its durability and maintaining its properties. The design ensures immunity to heaving processes and eliminates the risk of deformation during movement, which is why the acquisition of material fatigue is significantly slowed down.

Flaws

The disadvantages of USP foundations are mainly common to all slab foundations, but there are also specific points.

Disadvantages of USP:

1. High responsibility of work requires availability of qualified workers who have experience and a full understanding of the physical essence of the structure.

Mistakes made due to a misunderstanding of the principle of operation of the USP can reduce all the work to zero. Moreover, the finished foundation does not allow checking how well and carefully the work was done. All problems will “come out” only after several years of operation.

2. Built-in pipes are not only a convenient and successful solution, but also a possible problem - if something fails, repair will become a very difficult task.

3. It is believed that the maximum number of floors for USHP- three. Nevertheless, for reasons of safety margin, the maximum number of storeys for such a foundation is accepted two floors. Sometimes this situation forces one to abandon the attic and build a house from lighter materials, which raises certain doubts about the heat-retaining properties of the walls.

4. The floor of the first floor - the upper plane of the slab - is relatively low, which is often perceived negatively. There are concerns about snow and water getting into the house: if flooding occurs, the entire foundation may be under water.

5. The design does not allow for a basement. For a private home, this is a significant disadvantage, since it combines an auxiliary room, a storage room for storing supplies, a workshop, etc.

Reviews from home owners

There is a fairly large number of resources on the network where there is an active discussion of the Swedish plate as a type of foundation and as a technology in general. Owner reviews contain reviews of the USP foundation impressions of living in such a house. So, USP: reviews from owners (or rather, some of them).

“Building a house on USHP forced poor location of the site- lowland, clayey soil. We decided not to save money and did everything according to technology. Warm floors are great; your home is always cozy and warm. No problems have been noticed so far"

“I started building USHP simply because I wanted just such a foundation, although the terrain made it possible to do anything else. I haven’t regretted it yet, although pipes in concrete are somehow doubtful, but let’s hope for the best...”

“I was recommended by friends, they are construction specialists. I myself know little about these matters, relied on their knowledge and experience... In general, it’s great - heated floors, it’s always May at home.”

The general mood of all reviews is quite optimistic, although for a more correct coverage of the issue it would be nice to listen to the opinion of a person who has lived in a house on the USP for 10-20 years and find out what problems arise during this period and how difficult it is to solve them. So far, reviews of this kind have not been found about USP, because the practice of building such foundations is widespread relatively recently.

USHP turnkey foundation: price

Many of the disadvantages listed above for the USHP foundation are complemented by one more: the cost of the Swedish plate. Is it so? Let's see, What items does the cost of USP consist of:

• slab area;
• Cost of materials;
• delivery price;
• equipment rental;
• remuneration of work performers.

In different areas and conditions, prices may vary. differ significantly from each other, which is why USHP foundations have very different prices. First of all - prices for materials. Gravel and sand average 1 thousand and 500 rubles per cubic meter. m., respectively, insulation - about 1 thousand rubles per package (0.6 cubic meters), concrete grade M300 - about 3 thousand rubles / cubic meter. m. The costs of purchasing pipes for communications, for heated floors, etc. are also calculated here.

For your information: judging by the data available on the network, the cost of a turnkey UWB offered by various companies and the costs of people who built it themselves differ by 2-3 times.

The reasons for this discrepancy are desire to save money(it often turns out that during self-construction a person refused, for example, a heated floor), purchasing cheaper materials, etc. In addition, delivery costs significantly affect the total amount, and distances can be very different. And we also need to take into account wages: an indicator that indicates the qualifications, as well as the experience of workers.

Thus, it turns out that an insulated Swedish stove has a price per m2 of 2 to 8 thousand rubles, and the lower threshold of cost is a rather dubious indicator, it is taken from reviews of people who did everything on their own and with great simplifications. From here you can roughly deduce the total cost of USP: foundation 100 sq. m. m. will cost the amount 200-800 thousand rubles. Accordingly, the price of a Swedish slab foundation per square meter will be 2-8 thousand rubles.

It should be taken into account that in this case it is more advisable to contact a specialized organization and conclude an agreement for the construction of a turnkey USP foundation: the price will be higher, but it is worth it in order to have guarantees of compliance with the technology.

Selection criteria in comparison with other types of bases

Tape

Which is better: USP or? The high cost of USP is a reason that forces us to re-evaluate the validity of the choice and consider alternative options.

For example, the most common strip foundation. The cost of its arrangement is much lower, and it also allows you to equip a basement, which is a serious advantage. But you should remember in what conditions USHP is used, on what soils and what is obtained as a result of construction.

A strip foundation requires burial below the soil freezing level, which can mean a depth of 2 meters or more. High groundwater levels may make such an operation impossible. In addition, for a correct comparison, the cost of covering the basement floor should be added to the price of the strip base, since that is what USP is. At the same time, the cost of materials and payment for work is reduced. Thus, the choice is a strip foundation or an insulated Swedish stove: the price may be comparable.

Finnish plate

You can consider another replacement option -. She received the abbreviation UFF (Insulated Finnish Foundation).

The essence of the design is that the walls do not rest on a concrete screed, but on a separate shallow tape. This is the main difference between the Finnish and Swedish stoves.

Additional differences from USP are:

• the heated floor is not integrated into the slab and is installed during the finishing process;
• the need for additional formwork - if USHP requires formwork around the perimeter, then UFF is equipped with internal formwork, which increases the cost of work;
• less load on the slab, the floor bears purely operational loads.

According to experts, with UVF there are some unclear points- along with fairly detailed drawings, there are no digital values ​​anywhere with which more accurate calculations could be made. This gives rise to discrepancies and unequal approaches to arranging the foundation. The technology is crude and requires development in Russian conditions and more detailed analysis.

The cost of UFF, according to experts and reviews from owners, is approximately 15% higher than the price of a USHP slab, which is explained by the high complexity of the base, more intensive excavation work and the presence of additional operations in the technology.

Useful video

The advantages of a foundation made from an insulated Swedish slab are further described in the video below:

conclusions

Housing construction in most parts of the country is carried out under difficult conditions. Often the basis for choosing a location is proximity to the city limits, cost-effectiveness of communications and the availability of communication routes. The geological conditions of the site rarely correspond to favorable geographical data, so it is necessary to use techniques that are acceptable on difficult soils, and the disadvantages that, for example, the Swedish plate has, are stated as a fact.

Thus, the use of USP can be considered a forced measure, and the high cost of the Swedish slab foundation is at the cost of compensating for the adverse effects of the environment. Nevertheless, the result obtained justifies the expenses incurred and provides the opportunity to live in a warm and cozy home. We can only wait for new reviews: USP foundation technology continues to develop.

In contact with

Nowadays, USHP foundation is becoming increasingly popular. Do not forget that before choosing this type of foundation, it is important to have a complete understanding of all its pros and cons. In this article we will try to fully reveal all the advantages and disadvantages of the USP foundation. More precisely, we will mostly talk about the shortcomings of the USP foundation.

But, before we move on to talking about the disadvantages of this foundation, let's find out what a USHP foundation is?

The USHP foundation is a type of house foundation, mostly consisting of a monolith that has a shallow depth. It is clear that USP is an abbreviation that stands for insulated Swedish stove.

Disadvantages of USHP foundation

• USP has a significantly lower height when compared with other types of foundations. And this, of course, affects the quality of future housing. Of course, many people consider the safety of their lives to be one of the most important aspects. After all, in the end, if you build a poor-quality foundation, then the construction of the house itself will be of the same quality or may not take place at all.
• All the most important and necessary engineering communications are located directly inside the foundation, and this makes access to them much more difficult. And in our time, a variety of situations are possible in which urgent access to communications will be necessary, and its absence may entail the most irreparable consequences, including the need to destroy the foundations.
• In order to carry out installation and construction work, it is necessary to hire a professional team of builders, which also leads to additional financial costs. In this case, there is no way to save money, no matter how much you would like it, since poor-quality construction of the foundation will most likely lead to the construction of a living space that is not pleasant for living.
• When choosing USHP as a foundation, you should know that you will have to forget about building a basement. The thing is that this foundation, for technical reasons, makes it absolutely impossible to build a “basement.” But for people who live in rural areas, the basement is truly a “strategically important object”, since food supplies for the winter season are stored there. Therefore, before choosing a USP foundation in rural areas, you need to think three times.
• We all love beautiful, large, multi-story buildings, so if we use USP as a foundation, then the construction of multi-story buildings is out of the question. The technical feature of the USHP foundation is such that it is in no way designed for, so to speak, “heavy buildings”, but can only be used for the construction of one-story or small, two-story buildings.

Composition of the USHP foundation

The composition of the USHP foundation includes:

• Sand pillow
• Priming
• Communication pipes
• Crushed stone
• Expanded polystyrene, also known as insulation
• Reinforcing mesh
• Warm floor system, heating elements
• Concrete

Professional builders and USP developers strongly recommend building one-story or two-story small houses on the USP foundation. The thing is that the slabs of this foundation are not designed for excessively large loads. This is due to the fact that the height of the base of the USHP reinforced concrete slab is only 100 millimeters. Of course, if it is a two-story building, then the first floor does not need to be insulated.

Now, let's talk a little about the advantages that the USP foundation has.

Advantages of USHP foundation

Earlier, we already talked about the disadvantages of this type of foundation. Despite some shortcomings, it also has a number of positive features.

• It is possible to build the foundation of this foundation on a fairly large number of soils. Of course, there are a number of soils on which installation of this soil is not possible, but there is a positive point here too. If you are planning to build a house with a USP foundation, but you know that it is impossible to install it on this soil, contact a specialist and he will tell you what to do. There is a solution. In order to build a foundation on those soils where this cannot be done, you simply need to fill the area under the foundation with medium-grain sand and level it.
• This insulation has unique properties that prevent heat loss, and this allows you to save a significant amount of money on heating your living space.
• By and large, the base of the foundation itself is already a subfloor, on which absolutely any floor covering can be laid without any problems.
• In order to install the USHP foundation, you do not need to use heavy construction equipment, but a team of up to four people will do the installation of the foundation within two weeks.

Paying attention to everything we talked about, it is very important, as they say, to think a hundred times before choosing a foundation, and it is best to contact a specialist and together, take into account all the pros and cons of this or that type of foundation.

Construction of the house begins... Right. From an insulated Swedish stove.

Why insulated? Because one of the layers is extruded polystyrene foam.

Why Swedish? Because it was invented in Sweden.

Why a stove? Because it is a single whole.

The technology for creating this comprehensive solution is simple, but requires a thoughtful approach and does not forgive mistakes. The result is excellent, costs are lower, and the service life is long. Let's figure out what new engineers from the northern country proposed to create a foundation.

USP or insulated Swedish slab is a monolithic reinforced concrete slab of shallow laying, in which utilities and a floor heating system on the first floor are located. Its functionality and reliability are ensured by a number of preparatory measures, technical solutions, and innovative ideas.

Scope of application

The construction of buildings based on USP is widespread in Estonia.

USP can become most popular:

• in areas with a harsh climate (except for permafrost areas);
• in places close to the groundwater surface;
• for low-rise frame, panel, panel, block, brick construction;
• on soft soils.

Advantages of the stove

Construction of a building based on USP has the following advantages:

1. Life support engineering networks are laid either in the slab itself or under it. As a result, there is no need to install a basement or basement floor to accommodate communications, carry out work on insulation and protection of pipelines and cables, which reduces construction costs.
2. One of the foundation layers is thermal insulation. Its presence prevents the onset of seasonal cyclical operation (freezing - thawing).
3. The widespread use of waterproofing materials protects enclosing structures from moisture penetration, which increases their service life and heat-holding capacity.
4. The use of waterproofing materials, drainage, and sand and gravel “cushion” completely eliminates the destructive effect of moisture on the foundation.
5. Due to insulation using Swedish technology and the installation of a water-based “warm floor” system, operating costs for heating are significantly reduced.
6. The solidity of the structure, reliable reinforcement, and designed stiffeners provide greater load-bearing capacity and do not create restrictions on the building construction technology or the use of various building materials for the construction of walls, ceilings, and roofs.
7. Leveling the concrete base with subsequent grinding makes it possible not to carry out the final finishing of the floor of the 1st floor before laying finishing materials, which saves money and time.
8. The materials necessary for the creation of the USP are supplied to the construction site in small batches; their use does not require the use of cranes and heavy vehicles;
9. The laying of utility networks and the installation of the foundation are carried out within one technological operation, which reduces construction time.

Disadvantages of the slab

Just like every coin has two sides, USP has its drawbacks:

• the technology provides for the installation of USHP only on flat horizontal areas (the use of bulk soils makes it impossible to ensure the required strength);
• highly qualified specialists and designers are required (accurate calculations, impeccable implementation of the project when laying communications and performing reinforcement are required);
• the complexity of repairing communications requires the laying of backup lines.

Construction procedure

It is impossible to build a reliable foundation without clearly planning the course of action.

Design and survey work

If a small slab can be made with your own hands, then it is better to entrust the study of the structure of the soil, carrying out calculations, and drawing up a project to professionals. During the preparation of project documentation:

• groundwater level research is being carried out;
• the composition of the soil and its mobility are determined;
• The possibility of shifting layers under the influence of melt and rain water is being clarified.

Based on the initial data, the calculation is made:

• pit depths;
• characteristics of the drainage system and utility networks;
• thickness of the “pillow”, insulation layer and concrete;
• reinforcement diameter and rod laying pitch;
• floor heating pipeline.

All calculations are accompanied by detailed drawings that facilitate the construction process of the USP.

Pit preparation

The general technology for constructing a pit is as follows.

• The site is being cleared of fertile soil to a depth according to the project. The width and length of the cleared area must be at least 2 meters larger than the linear dimensions of the planned slab.
• Geodetic marking of the construction site is carried out using special instruments to maintain parallelism and perpendicularity of the enclosing structures. This is especially important with a complex configuration of the future home.
• The location where communications exit from the slab is marked.

Protection from water and laying of communications

The foundation must be kept dry at all times. To do this, a trench is dug along the perimeter of the pit to lay a perforated drainage pipe to drain melt, rain, and groundwater. The pipes are equipped with vertical outlets for cleaning. An underground reservoir is equipped to receive water, water from which can be used for household purposes.

In parallel with these works, measures are being taken to lay communications: hot and cold water supply, sewerage, electrical networks. The construction technology involves laying pipes that make it possible to create duplicate utility networks.

All networks are laid on a horizon located below the soil freezing level in the region.

It is not recommended to locate the main and backup systems under the stiffening ribs and directly in them due to the occurrence of large bending loads after the installation of enclosing structures.

Preparing the “pillow”

The bottom of the pit is compacted using a vibrating plate and covered with geotextiles. Before constructing a “pillow” of natural bulk materials, it is recommended to fill it with clay to about 10 cm and compact it. This will create additional waterproofing of the USP.

The “cushion” will reduce the impact of soil movements on the foundation. It is created from crushed stone (gravel, pebbles) and sand. Solid fine-grained materials are placed on the bottom layer, compacted and covered with geotextiles. Next, sand is poured (river or large quarry). It is subjected to compaction, alternating with water pouring to increase density, and covering with geotextiles.

Installation of insulation

To maintain operational characteristics, the foundation should not be subjected to freezing and soil pressure at subzero temperatures. To do this, a heat insulator is laid on top of the “pillow”.

The following requirements apply to the slab insulation:

• outstanding mechanical compressive strength;
• zero vapor permeability and zero water absorption;
• long service life;
• high heat holding capacity;
• chemical and biological stability.

The most suitable candidate for the role of USHP heat insulator is extruded polystyrene foam. Its technological protrusions ensure a tight fit of adjacent sheets and speed up the installation process.

The recommended thickness of the hydro-steam and heat insulator is at least 20 cm. It is preferable to lay the insulation in 2 layers. In this case, the slabs of the 2nd layer must overlap the joints of the 1st.

This will avoid the formation of cold bridges and freezing of individual foundation elements.

The insulation is installed according to the following scheme:

• The 1st layer completely covers the area of ​​the slab;
• The 2nd layer retreats from the outer perimeter by approximately 0.5 meters to create side ribs; grooves 20-30 cm wide are provided for installing the first level of the armored belt in them.

Insulation of the basement and blind area is being arranged.

Arrangement of formwork

The technology offers the production of formwork in two ways.

The classic option involves the use of wooden boards and (or) sheet wood products. In this case, they rest against the outer sides of the insulation slabs of the basement level. There is no direct contact between the formwork and concrete. It is possible to use the materials in subsequent construction.

The second involves the installation of L-shaped elements made of insulation. Installation is carried out with the lower support platform facing outwards. In this case, there is no need for additional work to insulate the blind area of ​​the future building.

Creation of an armored belt and a “warm floor”

To construct a reinforced belt, reinforcement and plastic fasteners (“chairs”, “cups”) are used. They provide ease of installation of fittings, placing them at the same height level. The minimum separation of the 1st layer of the belt must be at least 50 mm. The pitch of the threads and the diameter of the reinforcement are determined in design calculations.

The installation of a water pipeline for heating the floor of the 1st floor significantly increases the functionality of the USHP. It is laid between the first and second layers of reinforced belt, which ensures fixation of the pipe. It is possible to lay it on top of the second layer. In this case, special mats or stands are used for fixation, similar in design to reinforcement clamps.

The system collectors are raised to the design level and secured. When ready, pressure testing of the “warm floor” system is carried out.

Laying of pipes for floor heating is carried out according to hydraulic calculations according to a specific scheme, taking into account the installation of partitions and the arrangement of furniture.

Pouring concrete

The thickness of the concrete layer is determined by the design organization. Under load-bearing walls, in the stiffening ribs it can reach 20 cm, over the rest of the area it is about 2 times less. This allows you to significantly reduce the cost of purchasing ready-mixed concrete.

Pouring is done using a concrete pump. To obtain a monolithic slab, it is necessary to fill it in one day. The maximum possible interruption in the supply of ready-mixed concrete is 30 minutes.

During and after pouring, it is necessary to vibrate the solution due to the complexity of the layout, the presence of a large number of communications, and different layer thicknesses.

Only surface compaction is carried out, since touching the reinforcing belt and heating pipes is extremely undesirable.

To reduce the cost of subsequent grinding or installation of additional screed, the surface is leveled.

Before pouring the foundation, the floor heating pipes must be filled with air using a compressor to avoid them being compressed under the mass of concrete.

After the concrete has set (approximately 2 hours after laying it in the formwork), it must be moistened for 3 days. At high ambient temperatures, it is recommended to cover the surface with plastic film.

After three days, the foundation can be stripped. The solution will gain full strength within 28 days.

For final finishing, the surface is diamond polished. After this, work can be done on the construction of enclosing structures.

Usageinsulated Swedish stove allows you to quickly equip the foundation for a house with minimal construction costs, reducing the cost of finishing the 1st floor and subsequent savings on heating.