Insulation technology for slab foundation. Thermal insulation of the foundation slab - materials and options for heat saving Thermal insulation of a monolithic slab with expanded polystyrene

Insulation is an important part of any construction. All external parts of the building must be insulated from heat loss: walls, roof, basement and foundation. Insulation of the basement of the building not only limits heat loss, but also prevents frosty heaving of the soil. How is the insulation of a monolithic foundation carried out? And what are the features of installing insulation on the wall and floor of the foundation slab?

Insulation of foundations

Insulation of the foundation is necessary in those parts that are located in the zone of soil freezing. The base and the top of the foundation wall are covered with insulation. In addition, thermal insulation boards are placed under the outer blind area around buildings. These measures help protect the soil and walls from freezing and, therefore, avoid frost heaving of the earth around the house.

Various designs foundations have different ways insulation. Deep tape - only vertical walls near the surface of the earth are insulated, shallow tape - walls and sole. Pile foundation rests on non-freezing soil, therefore only the lateral surfaces of the piles are insulated.

Warming monolithic slab the foundation base is performed from the sides and from the bottom. This is necessary due to the location of the slab in the zone of soil freezing. A monolithic slab foundation is a shallow structure. Its depth rarely exceeds 50 cm. Therefore, the entire slab is located in the zone of freezing soil and requires high-quality insulation. What materials are used to insulate the foundation slab?

Foundation insulation material: Penoplex

Increased requirements for moisture and water resistance are imposed on the foundation insulation. It comes into contact with moist soil, therefore, in addition to insulation, it should prevent moisture from penetrating into the walls of the house. In addition, the foundation insulation must withstand compressive loads.

Perfect material for foundation insulation - extruded polystyrene foam. The trade name of the material is penoplex. It has a closed cell structure, due to which water and moisture do not penetrate into the material and do not form its destruction. Fluctuations in temperature near zero create an alternating liquid-ice state. When moisture is absorbed, the insulation cracks (as a result of freezing and expansion of water in the pores of the material). Therefore, ordinary expanded polystyrene (polystyrene) is not used in foundation insulation. You can use only moisture-resistant types of insulation: polyurethane foam or penoplex.

Water absorption characteristics

In addition to resistance to moisture and steam penetration, Penopex insulation can withstand significant compressive loads. Its price is higher than that of ordinary polystyrene. But it pays off in durability.

How to insulate: inside or outside?

How to properly insulate the foundation with penoplex - from the outside or from the inside? Theoretical calculations show that the location of the insulation on the outside protects the wall and slab from freezing. The location of the insulation inside the wall does not protect the wall and the slab, but it makes it possible to improve the microclimate in the room. This means that outdoor insulation is the most the best way for any building surfaces.

However, it is not always possible to carry out insulation from the outside. So for the foundation, external insulation is possible only at the construction stage. After that, the base can be insulated from heat loss only from the inside.

Warming the foundation slab from the inside gives a noticeable positive result: it becomes warmer and drier in the house. At the same time, the plate itself continues to freeze in the winter season, so its durability remains small.

If the slab was insulated during construction, then the foundation does not freeze and carries the load of the built house for a long time. How to insulate a slab foundation from the outside?

Penoplex insulation during the construction phase

Insulation during the construction phase involves laying the insulation on the ground before pouring the concrete. We list the sequence of actions for insulation during construction:

To eliminate the uneven pressure of the foundation on the ground, part of the soil is removed and gravel and then sand backfill is made. A layer of sand is spilled with water and carefully tamped.
After that, a layer of waterproofing and insulation plates are laid.
Reinforcement rods are placed on top of the insulating material and concrete is poured. In this case, the reinforcement rods are placed in two rows, the lower row is supported on plastic beacons (so that after pouring the reinforcement is inside the concrete).

In this way, a lightweight, durable and warm foundation, on which the walls of the building can be erected in a month.

Swedish foundation

Foundation insulated from below with polystyrene plates and equipped warm pipes is called Swedish. The abbreviated abbreviation for the foundation sounds like "USHP" or Insulated Swedish Slab.

The thickness of the base plate can vary from 10 to 30 cm (depending on the type of soil and the severity of the structure). The depth of such a foundation is higher than the soil freezing line. At the same time, frost heaving is taken under control and compensated for by external insulation of the slab.

Additional arrangement of heating allows you to get a foundation and a warm floor near the house at the same time. This design saves not only weight but also money. The amount of concrete for casting the base is reduced by one third. Reduced construction costs.

Advantages of an insulated foundation

We list the advantages that make the insulation of the foundation slab a necessary element of construction:

Saving concrete, reducing construction costs.
Acceleration of the construction of a house.
Reduction of heat loss and reduction of utility bills.
Improvement of the indoor microclimate.
Increase the durability of the foundation slab and the entire structure.

Such high advantages indicate that the insulated slab foundation is one of the best designs the foundations of the house.

rfund.ru

Thermal insulation of the foundation slab: the order of work

The slab base can withstand significant external influences and is suitable for construction in areas with complex, unstable soils, prone to frost heaving, with high level groundwater. Insulation of the foundation slab will help to significantly reduce heat loss through the base and reduce the effect of frost heaving of the soil. The structure, when the soil moves, rises and falls along with the foundation, which protects the structure of the house from the formation of cracks.

general information

The slab base structure consists of layers:

geotextile is covered with overlapping stripes on the sand layer, the joints are glued with tape;
crushed stone is poured in a layer of 15-20 cm;
fill in the leveling layer cement mortar, 5-10 cm thick;
be sure to isolate the structure from moisture using roll or coating materials;
arrange a heat-saving layer;
cover the plastic wrap with 20 cm overlap strips;
lay the reinforcing mesh;
poured with concrete.

Installation and insulation of a slab monolithic foundation is expensive due to high consumption building materials... When the soil freezes over great depth and a significant deepening of the strip foundation is required, the device of the slab will be cheaper, less land work will be required.

Advantages of a slab foundation

The slab base has the following advantages:

the concrete slab serves as the floor of the first floor, which further reduces the cost of its installation;
is an excellent option for the foundation of a house, the construction of which is carried out on floating soils, the slab and the whole house along with it move simultaneously with the soil;
the slab can be mounted on any type of soil, even on peat bogs and swampy areas;
the slab is erected above the level of soil freezing, thanks to the sand cushion, frost heaving practically does not affect the structure;
reinforced concrete slab is not subject to shrinkage;
suitable for the construction of buildings up to 3 floors.

Insulation of the foundation slab reliably protects it from deformation during seasonal heaving of the soil and prolongs the life of the structure.

Advantages of slab thermal insulation

Expanded polystyrene, polystyrene foam, polyurethane foam are used as heat-insulating material. Mineral wool is not suitable because of its low strength and high moisture absorption.

There is a technology for mounting a Swedish plate. The main difference is that concrete structure erected on a layer of heat-saving material, thanks to this, the soil under the house does not freeze and does not heave.

The main advantages of the Swedish plate are:

the construction of the foundation and the laying of communications are carried out in one technological cycle;
a heat-saving layer allows you to increase the efficiency of the warm floor;
installation of the foundation is carried out without the involvement of a large amount of construction equipment.

Around the buildings provide drainage system consisting of pipes for drainage of rain and melt water.

The design of the slab contributes to the transfer of all loads from the building to the layer of heat-saving material, therefore, increased requirements are imposed on the materials used.

Disadvantages of slab foundation

The slab foundation is not always the best option... You always need to carry out all the necessary calculations in advance and select the most suitable type of base for the house.

Disadvantages of the stove:

not suitable for construction on areas with a slope;
to build a house with a basement on a slab, you need to deepen to a great depth, this will be very expensive;
it is difficult to repair communications under the foundation slab;
during construction in winter, additional costs will be required for heating the concrete and maintaining the desired temperature on the site.

The slab foundation is erected only when the device of the strip base is impossible.

Insulation materials

The table shows the materials used to insulate the foundation slab and their characteristics:

No. Heat insulating material Characteristics

1	Styrofoam	Consists of air-filled cells. It is produced in the form of sheets, has insufficient density, so its surface needs additional protection.
2	Extruded polystyrene foam	It is able to withstand significant compressive loads without changing its size and structure. It is produced in the form of rectangular sheets with small cells filled with air. Lay the sheets in 1 or 2 layers. The second layer must be spread out so that the seams of the sheets of the first and second rows do not intersect. During installation, provide for the presence of holes for moisture drainage.
3	Polyurethane foam	It is a type of foamed plastic with many pores filled with air bubbles. The composition is prepared directly at the construction site. The two components are mixed, the result is a dense, solid foam that is applied to the surface. The plate insulated with polyurethane foam has high performance in heat and sound insulation, withstands the effects of moisture. Refers to low-combustible materials, and some brands are hardly combustible.

Most often, extruded polystyrene foam is used as a heater under the foundation slab.

Insulated plate installation

The construction of a monolithic slab foundation requires all calculations, taking into account geological, climatic conditions and the mass of housing construction.

Insulation of the slab foundation allows you to save significant money on heating the room during operation.

Site preparation

At the stage of creating the project, it must be borne in mind that the site for the foundation slab must be wider than the house building by at least 1 m on each side.

Instructions for performing preparatory work:

They clean the construction site from debris, the root system of trees and shrubs.
Mark the position of the slab according to the project.
They clean and remove the fertile soil layer. The depth of the slab depends on the geological and climatic conditions. Most often, the thickness of the slab varies from 20 to 30 cm, less often the base is deepened by 50 cm.
They dig a pit, manually level its bottom and side walls.
Pipes are installed around the perimeter to drain rain and melt water.
Spread the geotextile in overlapping strips. The material should cover the bottom and extend onto the walls along its entire height.
Wooden stakes or metal rods are driven in. Pull the cord strictly horizontally. It will serve as a guide for uniform filling of sand and gravel.
Sand is poured, 20-30 cm thick. Sand is evenly distributed over the entire area, moistened with water and compacted well.
Spread out geotextiles.
Crushed stone is poured, evenly distributed around the perimeter, carefully tamped.
They carry out all the necessary communications. They dig trenches for them in the rubble a little wider than the cross-section of the pipes. The pipeline is laid, a layer of sand is poured on top.
The sandy surface is leveled.

If the pipeline is laid before the stage of compaction of crushed stone, the pipes may crack.

Insulation of the slab

Step-by-step instructions for insulating a slab of a monolithic foundation:

Mount removable formwork from the boards, props are installed so that the structure does not fall apart under the weight of the concrete.
Pour a layer of concrete 50 mm thick.
After the cement mortar has completely solidified, sheets of foam are laid on it end-to-end and glued. Adhesive composition applied in dots along the perimeter of the sheet and in the center. A layer thickness of 10-20 cm is enough. The joints of the row are placed in a checkerboard pattern, with an offset of 1/3. When laying in two rows, the joints must not overlap.
Spread the dense polyethylene in overlapping strips. The joints are sealed with tape.
The reinforcement cage is laid, the formwork is poured with concrete.

After the slab has dried, the formwork is disassembled, the side walls are insulated with the same material that was used for laying under the slab.

The insulated plinth contributes to the increase in heat saving inside the room.

When installing insulation on bituminous insulation, you need to wait until it dries completely. If laid on a wet layer, the materials may be damaged and the effect of thermal insulation and waterproofing will decrease.

Heating pipes installation rules

Heating pipes are used during the installation of the UWB. There are such rules for laying them:

Tighter pipe laying allows for higher room heating temperatures.
The distance between external walls and pipes must not exceed 150 mm. Closer to the center, the paving pitch can be increased up to 250 mm.
To minimize hydraulic losses, the length of one loop should not exceed 100 m.
Do not lay pipes closer than 100 mm from each other.

Heating pipes must not be installed at the joints of monolithic plates. In this case, it is better to draw two contours. The pipeline crossing the joint is insulated with steel sleeves 30 cm long.

How to make an insulated Swedish stove with your own hands, you can watch the video: The insulated base plate allows you to reduce heating costs during operation and helps to reduce the level of frost heaving of the soil. Thanks to this, the life of the foundation is extended, and living in the house becomes more comfortable.

kakfundament.ru

Insulation under the foundation slab: step by step instructions

The monolithic slab base of the foundation has proven itself perfectly when used in soft and heaving soils. Annual freezing of soils in winter period leads to uneven rise and settlement of the slab base, which contributes to the occurrence of mechanical deformations that can cause the destruction of the slab itself and the building built on it.

A layer of horizontal insulation is capable of reliably isolating the foundation slab from the zone of frost heaving, contacts with soil moisture and preventing freezing.

The advantages of insulating a slab base

Horizontal insulation of the slab

High-quality insulation of the foundation monolithic slab guarantees the durability of the building and long-term operation without the need for unplanned repairs. It is especially important to insulate the foundation slab under residential buildings, when it is possible to avoid significant heat loss on the first floors of the house.

Insulation of the foundation slab must be performed for the following reasons:

Providing increased waterproofing of the foundation.
Significant reduction in heat loss.
Saving money for heating a residential building, real heat saving mode.
Preventing the formation of condensation that could destroy building construction building.
Improving the comfort of living.
Temperature stabilization during indoor areas operated residential building.

Materials for insulating a monolithic slab foundation

fundamentaya.ru

Insulation of a monolithic foundation slab from the inside

Warming a slab of any foundation is one of the most important things when building a house. It is best to do this in the warm season, and you cannot do it in rainy weather. Insulation of a monolithic foundation slab is especially important for cold regions where the soil freezes at great depths. When freezing, heaving soils can increase in volume, which leads to deformations of the entire building. Therefore, it is so important to take care of the external insulation of the foundation. This will help reduce the heat loss of the entire future building and preserve its durability.

What does foundation insulation give?

The better all the work is done, the longer and more reliable the building will stand. And most importantly, the house will keep warm even in severe frosts. Do not forget that most of the cold penetrates into the house through the foundation. And if the building has basement(billiard room, gym), then you should take care of the internal insulation. This is especially important if the basement is not heated. But the most important thing is the external insulation of any residential building.

The main reasons why insulation is necessary:

Improving waterproofing properties.
Reduced heat loss.
Reducing heating costs at home.
Preventing the formation of condensation on the walls.
Stabilization of the internal temperature of the building.

All this will help not only to always feel comfortable in your home, but will also increase its lifetime.

What kind of insulation to use for the foundation?

The most important part of the work when it is required to insulate a slab of a fresh foundation is the selection suitable material... It should not deform under soil pressure and absorb moisture. These are the most important parameters any thermal insulation. Soft materials such as rock wool will not work. The best options are polyurethane foam and extruded polystyrene foam. Both of them have excellent thermal insulation characteristics and a fairly low cost, which is also important during construction.

Polyurethane foam

This material is versatile, since it combines not only thermal insulation, but also sound and waterproofing properties. To use this type of insulation, you need special equipment, as it must be sprayed. For full-fledged insulation, 50 mm of insulation thickness, laid in several layers, is enough. All joints after insulation must be sealed.

This material has whole line positive properties:

low heat permeability;
good adhesion properties;
reliability;
durability.

And most importantly, when using polyurethane foam, there is no need to use additional means for steam, water and waterproofing. He has only one drawback - the need to use special equipment. Therefore, this method of insulation will require either considerable investment or the help of experienced specialists with the appropriate equipment.

Extruded polystyrene foam

This view insulation is much lower than polyurethane foam, it is easier to install. Such material consists of plates that do not pass or absorb moisture. It retains its thermal insulation properties for a long time even in cold regions. Advantages of extruded polystyrene foam:

high strength;
long service life;
reliable thermal insulation properties.

It is most often used when it is necessary to insulate the foundation, since it can be mounted independently, without using additional equipment.

Extruded polystyrene foam with grooves

This is a new type of insulation. Milling grooves on the surface of expanded polystyrene plates are excellent for warming the foundation. It is used in conjunction with geotextile fabric, as an attached drainage. Its main properties:

good thermal insulation;
protective layer of waterproofing;
waterproofness.

Insulation of the foundation with expanded polystyrene

To insulate a monolithic slab, you can use both expanded polystyrene and polyurethane foam. But the first option is preferable. Expanded polystyrene is the most effective and less expensive, and most importantly, it is easy to install. Before proceeding with its installation, it is recommended to lay the waterproofing, then you can proceed with the installation of the extruded polystyrene foam plates.

The most effective method of warming a foundation using this material is to use it in areas of soil freezing. Insulation is mounted to the depth of freezing. This is quite enough. When insulating, special attention should be paid to the corners: in such places, the used polystyrene foam should be thicker than in other areas. It is imperative to insulate the soil around the perimeter of the building. To do this, it is necessary to place a heater under the construction of the blind area.

All rows of extruded polystyrene foam boards should be stacked end-to-end, from bottom to top. Large joints are filled with polyurethane foam. This will provide high tightness, thermal insulation and waterproofing properties. Plates are planted on polymer glue or mastic, and then pressed with a layer of soil. When insulating, it is important to take into account that all plates are of the same width, you cannot use already used material, this can break the tightness. This method is suitable for all types of foundations, including monolithic ones.

Insulation of the foundation with polyurethane foam

When a monolithic foundation is insulated using polyurethane foam, it is important that there are no gaps or gaps. The insulation must form a completely closed loop. This will allow you to achieve maximum thermal insulation properties. It is sprayed onto the foundation using special equipment. The material then hardens within 20 seconds. In general, the whole process of installing insulation is quite simple and quick. The application of polyurethane foam is done in several layers, after each of them has dried. One layer should be about 15 mm thick.

At the end of all work, waterproofing is done and the foundation is sprinkled with soil. Equipment for the installation of such insulation can be purchased in specialized stores or rented. But it is easier and faster to use the services of professionals.

rfund.ru

Some effective building technologies have been developed recently. This is due to the appearance on the market of new materials with better or unique characteristics. Some of these techniques can be replicated an ordinary person after a relatively small study of the relevant materials. In this article, we will consider the process of warming with my own hands the foundations of a private residential building, another, relatively small structure.

Why you may need to insulate the foundation slab

Improving the insulation parameters of a building will make it easier and cheaper to operate. This fact alone is enough to think about carrying out the relevant work. Energy resources, despite temporary market fluctuations, will always be of high value. By reducing their consumption, it will be possible to count on significant savings in money.

It should also be noted that the correct engineering calculation will help to move the dew point beyond the contour of the main part of the structure. This means that moisture will not condense inside the structures. Thus, after the modernization, conditions for the appearance and development of mold will worsen, and latent corrosion processes will stop.

Separately, it is necessary to consider the heaving of soils. It takes place during the winter. These mechanical influences are capable of creating great pressure on the structural elements of the building. High-quality insulation of the foundation slab will prevent such and other harmful effects listed above.

Any technology becomes clearer by examples that confirm the feasibility of its application. In this case, you should pay attention to the “insulated Swedish plate” foundation. Here are the main parameters of this foreign technique, which is increasingly used today in domestic private housing construction:

It is a single structure made of cast concrete with reinforcement and stiffening ribs. It is installed on a pillow and surrounded by expanded polystyrene boards.
Sand is initially poured under the main insulation and on the sides of it.
A system for collecting water and discharging it into the drainage is pre-installed.
The blind area along the contour reduces the load on the drainage complex.
Providing comfortable temperature conditions produced using the "warm floor" system. It is built into the foundation at the stage of its creation.

This name itself defines the country of origin of the technology. In Sweden, it has been successfully used for more than half a century, and in Russia, individuals and construction companies have been using similar techniques for about ten years. Such timeframes are quite sufficient for well-grounded conclusions. Practical tests have confirmed the following features:

This technology for the construction of foundations is well suited for the construction of 1-2 storey buildings. For taller buildings it is necessary to order individual project... It will then have to be agreed upon in all official instances.
To completely exclude the possibility of flooding the structure during floods, a sand bed of the required height should be installed. To determine it, you can use statistical data for the desired region with the maximum levels. If necessary, additional measures are taken to improve the drainage and waterproofing system.
On sandy soils, you can save money during the construction process. There is no need for a productive drainage system.
Working with concrete, as in all other similar cases, is recommended only in a warm period. It is possible to fill the foundation in winter, but this will be accompanied by increased costs and increase the risk of marriage.
This design is especially effective in combination with a "warm floor". In particular, if the heating is turned off, even in the cold season, the heat will remain in the house for 72 hours.
A professional company is able to complete a full cycle of work in 3-4 weeks.

Material for creating a high-quality insulating layer

You can make a choice based on analogs of materials that are used in Swedish technology. But first, let's exclude unsuitable options:

Mineral wool different types do not have the necessary rigidity, strength and absorb water too well.
Expanded clay, other materials from granules. They are also not suitable, since they cannot become a dense, moisture-proof base for the future foundation.
Polymeric foam materials that are created directly on the job sites. Some of them can be applied. But the implementation of such a project will require certain skills. You will also need special equipment.

By the method of elimination, we found the "winner" of this correspondence competition. This is factory-made foamy polystyrene, penoplex. Let us list further those characteristics of the material that will be useful for solving the assigned tasks:

Its mode of production involves the release of standardized products. Thus, if you buy penoplex famous brand, then there will be no doubt that each plate will have the same parameters.
Exact dimensions and low weight will facilitate transportation, storage, installation operations.
The uniform distribution of closed bubbles in the structure of the foam provides excellent thermal insulation properties. To produce a full-fledged insulation of a monolithic foundation, it is not necessary to create a too thick layer.
This material is durable and does not allow moisture to pass through. Many types of slabs are made from it with special grooves along the edges, which makes it possible to ensure the tightness of butt joints without additional means.

Insulation of the slab foundation

We have found out the main parameters of this technique, so you can proceed to the description of the working operations. Consider the steps that are used to insulate the foundation slab:

For this group of works, it will be quite enough to create a layer of high-quality polystyrene foam with a thickness of no more than 10 cm. It can be formed from two rows of slabs, which are stacked in a checkerboard pattern with joint overlapping of the joint areas.
Site preparation should be carried out taking into account the geology of the site, the characteristics of the soil. When creating a depression, the bottom must be made even, therefore, manual labor is recommended in the final stages.
The sand is backfilled and compacted, after which a temporary formwork is installed, the first layer of concrete is poured without reinforcing elements.
When the base has hardened, penoplex plates are laid on it in the order indicated above. They are covered on top with a thick plastic wrap. The seams between the individual strips are carefully sealed with wide tape.
Next, the main foundation is created from reinforced concrete.
After it hardens, penoplex plates are attached to the end parts with an adhesive composition.

mynovostroika.ru

Insulation of a monolithic foundation slab with expanded polystyrene

It is difficult to build a solid foundation on unstable ground. In such cases, a slab base is used. It acts as a foundation of shallow depth, drifting along the site, while moving soil masses. Since the entire structure is moving, no destructive stresses arise.

For the correct operation of this type of foundation, it must be protected from freezing. Insulation of a monolithic foundation slab:

prevents the destruction of concrete from temperature differences;
promotes warm floor first floor;
makes it possible to save on heating the building;
reduces heaving of the soil under the building.

The choice of insulation

Not everyone, even the most effective material, suitable for work in the ground or in its vicinity. When choosing a material, you need to be guided by:

moisture resistance. Being saturated with water from the ground, the product loses its insulating properties. Expanding when freezing, moisture violates the integrity of the coating, nullifying all work;
strength. Seasonal movements of soil masses create perceptible pressure on the material. It is especially noticeable in rocky soils. Sharp edges can push through the product, leaving cracks or breaks in it;
resistance to aggressive environments. Soils are often chemically and biologically active. The groundwater may contain an increased concentration of salts. All these factors lead to the premature destruction of the insulation.

When installing insulation inside the building, the material must be non-combustible. If there is a possibility of fire, no harmful substances should be released that can cause suffocation.

With all this, the service life of the insulation should be no less than the service life of the finishing material. In this case, you do not have to change it before the coating becomes outdated. Otherwise, you will have to dismantle the finishing cloth that still meets the standards.

Extruded polystyrene foam is often used for zero cycle work. Insulation of the basement slab with expanded polystyrene, made in accordance with all the rules, allows you not to worry about the safety of concrete and saving heat.

Characteristics of expanded polystyrene

Expanded polystyrene is used for thermal insulation of the foundation slab:

outside;
from the inside;
in the body of concrete

Outdoor insulation technology

The height of the slab can be from half a meter. Freezing around the perimeter is the most dangerous for the foundation. Therefore, in general, the insulation is attached precisely along the side surfaces.

Before covering the foundation with a layer of insulation, it must be waterproofed. Despite the fact that polystyrene foam is waterproof, the coating is not seamless. Moisture penetrates into the seams between the slabs, which can destroy the slab.

Waterproofing is done by applying bituminous mastic or melting paraffin wax along the surface and edges of the slab. The second method is more economical and reliable. With help gas burner lumps of paraffin are melted. The material is evenly distributed over the surface, absorbing into it.

Waxing closes the pores of the concrete, creating a moisture barrier. Full adhesion helps to avoid flaking of the insulation. This means that insulation can be easily attached to it.

Expanded polystyrene plates are mounted on glue or on a cement-sand mortar. The first option allows you to carry out insulation when sub-zero temperatures... The underground part is fixed only by gluing. This is necessary to avoid disturbing the hydro-barrier.

The basement part of the insulation of the slab foundation with expanded polystyrene is additionally fixed with plastic dowels. For this, holes are drilled through the glued plates. They go through all the insulation and part of the foundation.

The adhesive is applied around the perimeter of the board and in several stripes in the center. It is kept for 1 minute and the plate is pressed to the surface for a couple of minutes. After gluing, the bottom plates are sprinkled with a layer of sand. This helps to fix them in the mounting position.

The second row of insulation is mounted with an offset of the seams. It is advisable to make bandaging and horizontal joints. This helps to avoid cold bridges.

If the thickness of the slabs is not enough, the insulation is carried out in two layers. Products with maximum thicknesses are taken to avoid the installation of several layers. The plates of the upper layer should overlap the seams of the lower ones.

Fixation with umbrellas is carried out at five points of the slab. The dowels are mounted after the plates are completely glued, but not later than three days later.

After installation, the seams are sealed with polyurethane foam. Excess foam is trimmed and the surface is plastered over the mesh. The mesh is necessary for better adhesion of polystyrene foam and plaster.

Internal insulation technology

When insulating a monolithic foundation slab from the inside, the material is laid in two ways:

Over the plate;
In the body of concrete.

In the first method, the sequence of work is as follows:

waterproofing is arranged along the foundation slab, with an approach to the wall;
logs are screwed on top of the waterproofing layer;
a layer of insulation is arranged between the lag;
over the insulation, a waterproofing film is attached to the logs;
a plank base, plywood or OSB boards;
over the subfloor, a cork, expanded polyethylene or pine needles backing is laid. A finishing floor is mounted on it.

You can do without lag. In this case, there is a complete insulation of the slab foundation with expanded polystyrene. The material is laid in a continuous layer. Immediately on top of it, the underlay and the final floor covering are laid.

When installed in concrete, following works:

the base plate is waterproofed;
a layer of insulation with a thickness of at least 100 mm is arranged. It is better to use products with a locking system;
a PVC film with a density of at least 1.42 g / cm3 is laid on the insulation;
reinforcing mesh is laid. Its role can be played by a masonry mesh with a cell of 100 * 100 mm;
the surface is filled with a screed not thinner than 5 cm;
the topcoat is laid on the screed.

For internal insulation, only self-extinguishing polystyrene foam should be used. For screed mounting, products of the G4 flammability class can be used.

Insulation of the body of the foundation slab

Warm concrete is used in many areas of construction. It can be purchased in the form of a ready-made mixture or manufactured in a construction site. For preparation, granular polystyrene foam is added to the initial mixture to form the foundation slab.

For the construction of structural elements, polystyrene concrete with a density of D1200 is used. When preparing 1 cube, the composition includes:

300 kg of M400 cement;
1.1 m3 of expanded polystyrene granules. It is better to use granular rather than crushed material. It is shaped like a ball, resulting in better enveloping cement mixture;
800 kg of sand;
PAD. Often saponified resin is added. Its presence in the composition provides better adhesion and increases heat-shielding properties.

When creating such concrete, you need to remember about shrinkage. It is 1mm per 1m of surface. The plate needs to stand for some time after curing. It is necessary to arrange a leveling screed over the surface.

The flammability class of such a product is G1. The concrete itself does not burn, but the insulation granules are exposed to fire. As a result, pores are created in the body of the foundation slab. They reduce the density of the structure and increase its moisture absorption.

The thermal conductivity of such a plate will be approximately 0.105 W / (m * C). The product requires additional insulation of the slab foundation from below. The thickness of the insulating material will be less than that of plain concrete.

The choice of the type and technology of insulation of the foundation slab depends on design features buildings and construction sites. Choose optimal solution is based on the data of the heat engineering calculation and comparison of the estimated cost.

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Insulation of the slab foundation - Technologies, subtleties, nuances

When choosing a foundation structure for a future building, each developer is guided primarily by its cost, reliability and durability. The ideal foundation that combines all these qualities is the monolithic foundation slabs, which can be erected on different types soil. But concrete has a high thermal conductivity, so developers need to take care of the insulation of load-bearing structures even in the process of performing construction work.

Warming methods

Insulation of the slab foundation must be carried out in the part that is located in the zone of soil freezing. The developer should lay insulation under the foundation slab, as well as under the outer blind area, which is necessarily created around the building. And also the basement of the building and the upper part of the foundation wall should be covered with a special material. Timely warming of the monolithic foundation slab will protect the soil adjacent to the building and its walls from freezing, thereby preventing frost heaving of the soil and minimizing heat loss at home.

When planning the insulation of a slab foundation, the developer must take into account the type of supporting structure:

Tape (in-depth). For insulation they use various materials, which are laid on the vertical surfaces of the supporting structure, above the ground surface.
Shallow strip foundation. For insulation, tile materials are used, which are laid on the sole and vertical surfaces of the supporting structure.
Pile. Only the lateral surfaces of piles deepened into the soil are insulated.
Monolithic tiled construction. The base slab is insulated not only from below, but also on the sides.

Benefits of timely insulation

The insulated slab foundation has a lot of advantages that every developer needs to know about:

Developers will be able to save concrete mortar, which is used in large volumes when pouring slab foundation structures.
The insulated foundation allows you to minimize heat loss. This has a positive effect on indoor climate and utility bills, which skyrocket during the winter months.
The timing of construction work is accelerating.
The term is maximized useful use the supporting structure, since it ceases to be adversely affected by moisture and low temperatures.
The insulated base plate prevents condensation on the interior walls premises.
Service life is maximized waterproofing materials, which are involved in the construction of slab foundation structures.

What materials can be used to insulate a slab foundation?

Currently, a huge range of materials is presented on the domestic construction market that developers can use when carrying out insulation measures:

Polyurethane foam. This material is made of foamed plastic, which has a porous structure filled with air bubbles. This insulating mixture is created directly at the construction site and applied to the foundation structures using special equipment. The components that have entered into a chemical reaction are already at concrete surfaces form a durable foam that hardens almost instantly. This material helps to minimize heat loss, prevents extraneous noise from the street from entering the premises, does not undergo putrefactive changes in constant contact with a humid environment, and is highly resistant to ignition.
Styrofoam. This material has been used for decades in the construction industry as insulation. Its main disadvantage is its low mechanical strength, which is why it needs additional cladding.
Extruded expanded polystyrene. This material has a fine-mesh structure and is supplied to the construction market in the form of rectangular sheets. It has excellent technical properties, is able to withstand high loads, without changing either the internal structure or the geometric shape. In recent years, developers have used extruded polystyrene foam when insulating slab foundation structures, since it does not need additional protection and can perform the functions assigned to it for decades.

In recent years, many developers prefer to carry out insulation of the foundation with penoplex. The choice of this material is due to the fact that it is highly resistant to moisture, and also has the lowest thermal conductivity. Due to the fact that the slab supporting structure will have to be in contact with a humid environment for many decades, insulation of the foundation with foam will help protect the building from its harmful effects.

Extruded polystyrene foam is ideal for thermal insulation of monolithic foundation structures, as it can withstand compressive loads. Polyurethane foam boards and polystyrene foam are cellular materials with a closed structure, due to which moisture is not able to penetrate into their cavities. That is why they are used when carrying out insulation measures.

Insulation rules for slab foundation structures

Before insulating the slab foundation, the developer must learn about all the features and nuances, as well as the most effective technologies. If the foundation is insulated with foam from the outside, then this will protect not only the slabs, but also the walls from freezing. In the event that the expanded polystyrene panels are laid on the inner sides of the walls, the developer will be able to significantly improve the indoor microclimate, but at the same time, the slabs and walls of the building will not be protected from freezing. From this it follows that the external insulation of the foundation with penoplex will be ideal option for any construction site.

External insulation of the foundation with expanded polystyrene or expanded polystyrene is possible only on initial stages construction. If developers miss this moment, then in the future they will only be able to spend internal insulation foundation with penoplex or polyurethane foam.

Carrying out insulation measures during construction

The procedure for warming the foundation with expanded polystyrene must be carried out at the initial stage of construction work. Developers should strictly follow the technology:

First of all, a pit is dug, in which a monolithic slab of concrete will be created. Its depth should be 1 meter. Depressions are made at the bottom into which drainage pipes whose functions are to divert surface waters into specially created wells. Such measures will protect not only the foundation, but also the walls of the building from getting wet.
After laying the drainage pipes, the bottom of the trench is leveled and a special material is rolled out on its surface - geotextile. It will prevent the germination of rhizomes of trees and shrubs that can disrupt the integrity of the supporting structure.
A layer of sand and gravel is laid on top of the geotextile. Thus, at the bottom of the pit, a sand-crushed stone cushion is created (approximately 30-40 cm thick).
Are being laid engineering Communication such as plumbing and sewer pipes... After laying, the surface is sprinkled with sand and leveled.
Formwork is being constructed along the perimeter of the prepared pit. For these purposes, it is customary to use boards or sheets of moisture-resistant plywood. Outside, the formwork must be supported with jibs or stops in order for the wooden structure to withstand the load that the concrete solution will exert on it.
A small amount of concrete is poured into the bottom of the pit, which will create the first foundation layer. After it has solidified, the developer must proceed with waterproofing and thermal insulation measures.
Due to the fact that a monolithic concrete slab will constantly be in the ground and in contact with a humid environment, the developer must perform its high-quality waterproofing. For these purposes, in the construction industry, it is customary to use roll material or coating. The concrete base must be thoroughly cleaned of debris and then dedusted. To increase its adhesive properties, it is recommended to carry out treatment with diluted kerosene or solvent. After that, roofing material is rolled out on the prepared concrete base, the canvases of which should overlap. All joints should be treated with mastic, after which experts recommend laying another layer of waterproofing. If the developer decides to use liquid insulation, then he needs to apply it several times to the surface of the concrete base and, after complete drying, continue construction works.
At the next stage, the slab is insulated. For these purposes, most developers use sheets of extruded polystyrene foam (15 cm thick). Such material is laid, as a rule, in two layers. Make sure that the top sheets overlap the joints of the bottom panels.
Reinforcement of the foundation structure is carried out, due to which its strength and bearing characteristics.
The concrete solution is poured in several stages. After pouring the first batch, the developer must use a deep vibrator to remove air and eliminate the resulting voids. After that, the remaining solution is poured out.

After the concrete has set, the developer can continue construction work. In order to maximally protect the building from the harmful effects of harmful environments, he must also carry out internal insulation of the foundation. For this, sheets of extruded polystyrene foam should be used, which are glued to the floor and walls of the premises and are subsequently finished.

Foundation - insulated Swedish slab (USHP) refers to slab foundations.

A distinctive feature is that this foundation, among many, is a more progressive and original type of foundation, which, in principle, corresponds to the most modern requirements on the energy efficiency of the house, and, in principle, the construction of the foundation as a whole. The UWB foundation for the post-Soviet era is a relatively young option.

For the first time, information about the foundation of the insulated Swedish plate appeared on construction forums 10 - 15 years ago. There he was very actively discussed. But a number of points that you should definitely know when using such foundations have been omitted. Mostly there were laudatory odes to this foundation.

Pros and cons of UWB

Advantages of USB, as well as of all slab foundations	Disadvantages of USB and all slab foundations
The loads are transferred fairly evenly, since the slab, more than just a tape, distributes the loads and transfers them evenly to the base in the form of soil under the foundation.	They are subject to the risks of heaving and uneven settlement, since they are located in an unfavorable zone of soils with a low bearing capacity, as well as in the freezing zone, because they are not deepened by the supporting base to the depth of freezing.
Monolithicity. All monolithic work on pouring the foundation with concrete is carried out in one step. When pouring, a concrete pump and a deep vibrator must be used. The result is a monolithic concrete layer, which is very important for the foundation.	There are nuances on the arrangement of communications and the relief of the site
Small amount of work. Unlike monolithic strip foundations, there is much less work on the USH, both earthen and about tying reinforcement, concrete acceptance, and formwork.

Differences from a conventional slab foundation:

A large amount of insulation is used in the device of the UWB. It is used along the perimeter of the foundation and, as a rule, not to the depth of freezing, but to the depth of the foundation device, this is usually 600 mm, which corresponds to the standard size of the sheet of extruded polystyrene foam.

Also, the insulation is used directly under the stove and the blind areas are necessarily insulated.

This type of foundation, according to Dmitry Marchenko, is far from ideal. Marchenko believes that the choice of this type of foundation is more related to failure decisions than rational decisions.

After this type of foundation was promoted on construction forums, it was actively picked up by the manufacturers of expanded polystyrene insulation made technological maps, instructions for arranging these types of foundations. As a result, the topic of USHB received even greater status as a professional solution for the foundation of a private house. It is not without reason that these manufacturers became interested in this particular technology of foundations - a very large amount of insulation was used in it and most of it was used simply irrationally, one could easily do without it.

Marchenko expresses the opinion that this technology is rather beneficial not for the owners of the future house, not for builders, it is beneficial specifically for the producers of expanded polystyrene.

Dmitry Marchenko studied this foundation in detail and did not see any other persons interested in this foundation, except for the producers of extruded polystyrene foam.

How rational is the UWB foundation?
On many sites promoting this foundation, you can see a large list of its benefits. According to Dmitry Marchenko, most of these advantages are simply far-fetched and, in fact, have no evidence.

Reality and advertising via USP

ADVANTAGES SPECIFIED FOR USHP	VALIDITY OF THE USHB FOUNDATION
USB is a fairly cheap type of foundation, because a much smaller volume of reinforcement and concrete is used, a much smaller volume of earthworks and monolithic works.	In comparison, a strip monolithic foundation is usually taken. Indeed, less concrete is used in USP - the slab thickness is only 100 mm and less reinforcement - reinforcement is knitted in just one layer. But long-term practice shows that one layer of reinforcement is not enough here. You need 2 layers of reinforcement and they must be tied up with clamps with a certain step, make additional "pawns" from the reinforcement. But this is not the case in the proposed USWB technology. Therefore, the main disadvantage of this foundation is a weak slab. Also, a lot of high-quality insulation is used in this foundation. And any insulation will not work here, you need high-quality and expensive extruded polystyrene foam. And for example, for a house with a slab measuring 10 x 10 meters, 18 cubes of insulation are required. And the foundation with so much insulation becomes simply “golden” in value. At a price, it even covers a monolithic strip foundation. Therefore, such an advantage as a low price is fundamentally wrong. Also, not the cheapest pleasure is the device of a sand cushion. First you need to choose your native soil, then bring in the sand, the sand must be moistened in layers and compacted, all this must be MUST be observed. These are additional costs.
USHP is suitable for the construction of houses on any soil, both heaving and non-permeable, and subsiding and non-subsiding, etc.
This foundation evenly distributes the loads.
Suitable for all types of houses - timber, brick and lightweight concrete, etc.

The thickness of the sand cushion is 300-400 mm, then it is very rarely possible to achieve high-quality compaction of sand. Very often builders neglect this.

For example, they do not do it in layers or do not shed enough or, on the contrary, fill in the sand and then it cannot be tamped properly. And even if all this is carried out efficiently, all the same, uneven ramming places are possible throughout the entire area of the sand cushion. As a result, this will lead to the fact that the base of a sand cushion under the house, and it will not be local, but common to all slabs, may turn out to be uneven and will lead to uneven shrinkage of the foundation. uneven shrinkage of the foundation, in turn, will entail possible cracking of the foundation, and then the reinforcement in one layer will be extremely insufficient for the foundation to retain its geometry and not crack, which will result in a crack in the load-bearing structures of the house. Thus, the sand cushion affects the stability of the whole house.

Also, the disadvantage is the possible deformation of the EPS itself. Despite the fact that the manufacturer claims high technical and operational characteristics of its products, that the material has very high compression rates, practice shows that at high loads it works, at least, not as stated in its characteristics. This means that material deformations are possible, which will lead to uneven shrinkage of the foundation. Extruded polystyrene foam directly under the foundation slab receives enormous loads in the form of pressure from the side of the house, which means its durability is questionable. Despite the fact that manufacturers claim ideal qualities, there are very few stories of using EPS in this way, there is no information on its caking for 10-15-20 years, and this calls into question the integrity of the whole house. There is no certainty that a person will want to risk their investments in a house in order to experiment on themselves how the EC manufacturer was conscientious.

The disadvantages of this foundation, like other slab foundations, is a low base. Usually it is 10 cm already from the mark of the blind area and the wall structures of the house are very close to the ground, which means they will be in a zone of high humidity, which is a very vulnerable moment for our climate. A plinth with a height of 10 cm is not enough for our climate; in our climatic conditions, the plinth should have a height of 50-60 cm. This will provide a sufficient distance from the ground for wall structures and remove any moisture and snow from them. Like other types of slab foundations, this foundation will require a flat area and the absence of any slopes from either side towards the house. any rain or melt water will soak the lateral parts of the foundation base and these places will heave unevenly, undermine the blind area, it may even lead to the lifting of some part of the foundation, and with an uneven play of the foundation, deformations may occur on the foundation or on the wall structures.

Most technological maps or instructions for arranging this foundation imply a drainage system. It must necessarily be arranged in a warm zone of the earth, otherwise the drainage will most likely simply burst with heaving in the first winter. It will be filled with water and in winter, when the temperature is below zero, it will simply freeze and tear it apart. But any drainage system has a tendency to silting up, and in this case, this system just under the house will have a great tendency, because already at the stage of building the foundation of the house, it will be exposed to possible risks of clogging from the workers, the vibrating plate will work. Of course, protection is arranged in the form of geotextiles, but practice shows that there are junction points and some drawbacks of the builders, as a result, the drainage systems are flooded. There is a way out that partially solves the situation, inspection hatches are being built through which it is possible to rinse drainage systems under the pressure of water, but in most cases hidden drainage systems are not the best solution, especially if it is not specialists in drainage that will deal with it, but ordinary builders. foundation device. In such cases, it is very often overlooked. important points, because if there is no practice, it cannot be replaced with information from the Internet. Moreover, it is not enough to simply lay drainage pipes. It is necessary to make a branch with a slope, you need to make a receiving well, install drainage pump... This will increase the cost of construction even more.

On the site you will have to allocate space for a drainage well., regularly maintain and monitor it, clean the drainage system, which is likely to be completely silted up in 5-10 years. And the maintainability of drainage systems in these places is simply impossible. Any excavation work in this location will simply result in foundation settlement. This is another disadvantage to questions about the price of this foundation. On this, we can already, in principle, say that this type of foundation is not profitable.

But his shortcomings do not end there.
Private houses are usually built outside the city, where they are found in a large number rodents, ants, etc. And the insulation under the foundation for them is an ideal place for arranging holes. The insulation will not be integral, and the pressure from the house will remain the same. Hence, deformations, subsidence of the insulation are possible, and with it subsidence of the foundation. And within 10-5 years, the picture with the geometry of the foundation can drastically deteriorate.
There is a solution that is partially used in the construction of any house, since it is always rational to insulate the blind area of the house, to insulate the foundation in order to exclude freezing of the slab, to exclude frost penetration under the foundation, even a monolithic one, therefore, when installing insulation from EP, the right solution is always to equip a protective mesh ... But if you protect the entire volume of insulation with a metal mesh, then it is very expensive, and it is not a fact that ants cannot get there.

As for underfloor heating when constructing this foundation: The layout of pipes for underfloor heating can already be carried out at the stage of its construction. Underfloor heating pipes are fastened with clamps to fittings, which are located at the bottom of the slab. And as a result, after pouring, you get a ready-made foundation in which the pipes of the warm floor are located, which means that you will not need to make the installation of underfloor heating according to the insulation as a classical system, when an insulator is arranged on a monolithic slab of the house, underfloor heating pipes are laid, a screed is made, and as a result you also get a warm floor, but you pay extra money for this work.

The floor screed, which is arranged along the pipes of the warm floor, has a relatively low density, and, accordingly, the heat capacity, in comparison with a monolithic slab. This makes it possible for the underfloor heating pipes to relatively quickly warm up the screed layer and give off heat to the room. If you look at the underfloor heating system in the USHP, then in contrast to the classic screed. we get: the stove itself has a high density and high heat capacity, which means that in order to heat this stove, the boiler must work much more. and you will have to pay more for this in order to warm up the entire volume of concrete, and only then will it give high-quality heat to the room. And if from floor heating pipes to finishing coating thickness is 5-6 cm, then in the case of UWB this distance increases by 2-2.5 times. And in order to warm up your house, you have to warm up the stove itself for 1-2 days, and only then some kind of thermal effect from the pipes of the warm floor will begin. This system is very slow to warm up and cool down. therefore, if we compare the device of underfloor heating, then the classical system is more advantageous, because it allows, at a lower cost in heat energy, to quickly transfer this energy to the room.

Because Since this system is directly connected to water, then it may have problems with leaks. The builders can accidentally crush or damage the pipe, which could lead to the need for repairs. In the case of the classical system, the screed breaks, the place of breakdown is found and eliminated. It is not difficult to find the place of breakdown here, since it will show a wet stain on the floor. and in the case of a monolithic slab, finding the place of damage will be quite problematic, you will also have to make a lot of efforts to get to the pipe, and the solidity of the supporting structure of the house will be broken. And in the case of a screed, the search and elimination of the hole will not affect the integrity of the supporting structures.

Like all other slab foundations, this foundation requires a clear technological calculation, as well as a clear understanding and a clear device. engineering systems zero cycle already at the foundation stage. Those. if, when installing other types of foundations, you have the opportunity to think about moving the pipe leads before installing the plumbing, then with this system you cannot move the pipes that have already been removed. ,
If you are faced with the fact that pipes, sleeves come out of the foundation slab, always protect them, covering them with something is an incomplete solution, the most proven is to make boxes of wood. ...
The technology is beneficial for manufacturers of extruded polystyrene foam.

Insulation of foundations

Insulation of the foundation is necessary in those parts that are located in the zone of soil freezing. The base and the top of the foundation wall are covered with insulation. In addition, thermal insulation boards are placed under the outer blind area around buildings. These measures help to protect the ground and walls from freezing and, therefore, avoid the earth around the house.

Different foundations have different insulation methods. Deep tape - only vertical walls near the surface of the earth are insulated, shallow tape - walls and sole. The pile foundation rests on non-freezing soil, therefore only the lateral surfaces of the piles are insulated.

Insulation of a monolithic foundation slab is performed from the sides and bottom. This is necessary due to the location of the slab in the zone of soil freezing. A monolithic slab foundation is a shallow structure. Its depth rarely exceeds 50 cm. Therefore, the entire slab is located in the zone of freezing soil and requires high-quality insulation. What materials are used to insulate the foundation slab?

Foundation insulation material: Penoplex

The ideal material for foundation insulation is extruded polystyrene foam. The trade name of the material is penoplex. It has a closed cell structure, due to which water and moisture do not penetrate into the material and do not form its destruction. Fluctuations in temperature near zero create an alternating liquid-ice state. When moisture is absorbed, the insulation cracks (as a result of freezing and expansion of water in the pores of the material). Therefore, ordinary expanded polystyrene (polystyrene) is not used in foundation insulation. You can use only moisture-resistant types of insulation: polyurethane foam or penoplex.

Water absorption characteristics

How to insulate: inside or outside?

How to properly insulate the foundation with penoplex - from the outside or from the inside? Theoretical calculations show that the location of the insulation on the outside protects the wall and slab from freezing. The location of the insulation inside the wall does not protect the wall and the slab, but it makes it possible to improve the microclimate in the room. This means that external insulation is the best option for any building surfaces.

If the slab was insulated during construction, then the foundation does not freeze and carries the load of the built house for a long time. How to insulate a slab foundation from the outside?

Penoplex insulation during the construction phase

Insulation during the construction phase involves laying the insulation on the ground before pouring the concrete. We list the sequence of actions for insulation during construction:

To eliminate the uneven pressure of the foundation on the ground, part of the soil is removed and gravel and then sand backfill is made. A layer of sand is spilled with water and carefully tamped.
After that, a layer of waterproofing and insulation plates are laid.
Reinforcement rods are placed on top of the insulating material and concrete is poured. In this case, the reinforcement rods are placed in two rows, the lower row is supported on plastic beacons (so that after pouring the reinforcement is inside the concrete).

In this way, a light, durable and warm foundation is obtained, on which the walls of the building can be erected in a month.

Swedish foundation

The foundation, insulated from below with polystyrene plates and equipped with warm pipes, is called Swedish. The abbreviated abbreviation for the foundation sounds like "USHP" or Insulated Swedish Slab.

USHP - Insulated Swedish Plate

Advantages of an insulated foundation

We list the advantages that make the insulation of the foundation slab a necessary element of construction:

Saving concrete, reducing construction costs.
Acceleration of the construction of a house.
Reduction of heat loss and reduction of utility bills.
Improvement of the indoor microclimate.
Increase the durability of the foundation slab and the entire structure.

Such high advantages indicate that the insulated slab foundation is one of the best structures for the base of the house.

Insulation of the foundation slab updated: February 26, 2018 by: zoomfund

The slab base can withstand significant external influences and is suitable for construction in areas with complex, unstable soils, prone to frost heaving, with a high level of groundwater. Insulation of the foundation slab will help to significantly reduce heat loss through the base and reduce the effect of frost heaving of the soil. The structure, when the soil moves, rises and falls along with the foundation, which protects the structure of the house from the formation of cracks.

general information

The slab base structure consists of layers:

geotextile is covered with overlapping stripes on the sand layer, the joints are glued with tape;
crushed stone is poured in a layer of 15-20 cm;
the leveling layer of cement mortar is poured, 5-10 cm thick;
be sure to isolate the structure from moisture using roll or coating materials;
arrange a heat-saving layer;
cover the plastic wrap with 20 cm overlap strips;
lay the reinforcing mesh;
poured with concrete.

Installation and insulation of a slab monolithic foundation is expensive due to the high consumption of building materials. When the soil freezes to a great depth and a significant deepening of the strip foundation is required, the device of the slab will be cheaper, and less land work will be required.

Advantages of a slab foundation

The slab base has the following advantages:

the concrete slab serves as the floor of the first floor, which further reduces the cost of its installation;
is an excellent option for the foundation of a house, the construction of which is carried out on floating soils, the slab and the whole house along with it move simultaneously with the soil;
the slab can be mounted on any type of soil, even on peat bogs and swampy areas;
the slab is erected above the level of soil freezing, thanks to the sand cushion, frost heaving practically does not affect the structure;
reinforced concrete slab is not subject to shrinkage;
suitable for the construction of buildings up to 3 floors.

Insulation of the foundation slab reliably protects it from deformation during seasonal heaving of the soil and prolongs the life of the structure.

Advantages of slab thermal insulation

Expanded polystyrene, polystyrene foam, polyurethane foam are used as heat-insulating material. Mineral wool is not suitable because of its low strength and high moisture absorption.

There is a technology for mounting a Swedish plate. The main difference is that the concrete structure is erected on a layer of heat-saving material, thanks to which the soil under the house does not freeze or heave.

The main advantages of the Swedish plate are:

the construction of the foundation and the laying of communications are carried out in one technological cycle;
a heat-saving layer allows you to increase the efficiency of the warm floor;
installation of the foundation is carried out without the involvement of a large amount of construction equipment.

Around the building, a drainage system is provided, consisting of pipes for the removal of rain and melt water.

The design of the slab contributes to the transfer of all loads from the building to the layer of heat-saving material, therefore, increased requirements are imposed on the materials used.

Disadvantages of slab foundation

A slab foundation is not always the best option. You always need to carry out all the necessary calculations in advance and select the most suitable type of base for the house.

Disadvantages of the stove:

not suitable for construction on areas with a slope;
to build a house with a basement on a slab, you need to deepen to a great depth, this will be very expensive;
it is difficult to repair communications under the foundation slab;
during construction in winter, additional costs will be required for heating the concrete and maintaining the desired temperature on the site.

The slab foundation is erected only when the device of the strip base is impossible.

Insulation materials

The table shows the materials used to insulate the foundation slab and their characteristics:

№	Heat insulating material	Specifications
1	Styrofoam	Consists of air-filled cells. It is produced in the form of sheets, has insufficient density, so its surface needs additional protection.
2	Extruded polystyrene foam	It is able to withstand significant compressive loads without changing its size and structure. It is produced in the form of rectangular sheets with small cells filled with air. Lay the sheets in 1 or 2 layers. The second layer must be spread out so that the seams of the sheets of the first and second rows do not intersect. During installation, provide for the presence of holes for moisture drainage.
3	Polyurethane foam	It is a type of foamed plastic with many pores filled with air bubbles. The composition is prepared directly at the construction site. The two components are mixed, the result is a dense, solid foam that is applied to the surface. The plate insulated with polyurethane foam has high performance in heat and sound insulation, withstands the effects of moisture. Refers to low-combustible materials, and some brands are hardly combustible.

Most often, extruded polystyrene foam is used as a heater under the foundation slab.

Insulated plate installation

The construction of a monolithic slab foundation requires all calculations, taking into account geological, climatic conditions and the mass of housing construction.

Insulation of the slab foundation allows you to save significant money on heating the room during operation.

Site preparation

At the stage of creating the project, it must be borne in mind that the site for the foundation slab must be wider than the house building by at least 1 m on each side.

Instructions for performing preparatory work:

They clean the construction site from debris, the root system of trees and shrubs.
Mark the position of the slab according to the project.
They clean and remove the fertile soil layer. The depth of the slab depends on the geological and climatic conditions. Most often, the thickness of the slab varies from 20 to 30 cm, less often the base is deepened by 50 cm.
They dig a pit, manually level its bottom and side walls.
Pipes are installed around the perimeter to drain rain and melt water.
Spread the geotextile in overlapping strips. The material should cover the bottom and extend onto the walls along its entire height.
Wooden stakes or metal rods are driven in. Pull the cord strictly horizontally. It will serve as a guide for uniform filling of sand and gravel.
Sand is poured, 20-30 cm thick. Sand is evenly distributed over the entire area, moistened with water and compacted well.
Spread out geotextiles.
Crushed stone is poured, evenly distributed around the perimeter, carefully tamped.
They carry out all the necessary communications. They dig trenches for them in the rubble a little wider than the cross-section of the pipes. The pipeline is laid, a layer of sand is poured on top.
The sandy surface is leveled.

If the pipeline is laid before the stage of compaction of crushed stone, the pipes may crack.

Insulation of the slab

Step-by-step instructions for insulating a slab of a monolithic foundation:

A removable formwork from boards is mounted, supports are installed so that the structure does not fall apart under the weight of concrete.
Pour a layer of concrete 50 mm thick.
After the cement mortar has completely solidified, sheets of foam are laid on it end-to-end and glued. The adhesive composition is applied in dots along the perimeter of the sheet and in the center. A layer thickness of 10-20 cm is enough. The joints of the row are placed in a checkerboard pattern, with an offset of 1/3. When laying in two rows, the joints must not overlap.
Spread the dense polyethylene in overlapping strips. The joints are sealed with tape.
The reinforcement cage is laid, the formwork is poured with concrete.

After the slab has dried, the formwork is disassembled, the side walls are insulated with the same material that was used for laying under the slab.

The insulated plinth contributes to the increase in heat saving inside the room.

When installing insulation on bituminous insulation, you need to wait until it dries completely. If laid on a wet layer, the materials may be damaged and the effect of thermal insulation and waterproofing will decrease.

Heating pipes installation rules

Heating pipes are used during the installation of the UWB. There are such rules for laying them:

Tighter pipe laying allows for higher room heating temperatures.
The distance between external walls and pipes must not exceed 150 mm. Closer to the center, the paving pitch can be increased up to 250 mm.
To minimize hydraulic losses, the length of one loop should not exceed 100 m.
Do not lay pipes closer than 100 mm from each other.

Heating pipes must not be installed at the joints of monolithic plates. In this case, it is better to draw two contours. The pipeline crossing the joint is insulated with steel sleeves 30 cm long.

How to make an insulated Swedish stove with your own hands, you can watch the video:

The insulated base plate allows you to reduce heating costs during operation and helps to reduce the level of frost heaving of the soil. Thanks to this, the life of the foundation is extended, and living in the house becomes more comfortable.

Insulation of a monolithic foundation slab is necessary in areas with cold climates. Such measures are required in order to protect the base from harmful effects. the environment, keeping warm, coziness and comfortable living conditions in the house. One of the most common materials for insulation are polystyrene foam and polyurethane foam.

Insulation of the foundation of a monolithic type with expanded polystyrene

Thermal insulation of base plates in this way is a relatively young form of modification of private houses. It began to be used in the 50s - 60s of the XX century. This type of slab insulation is durable and has a long service life. According to statistics, the popularity of expanded polystyrene is growing steadily every day.

Strengthening monolithic slabs with expanded polystyrene proved to be very good decision in the construction of houses, because their service life is more than 50 years. After carrying out various tests and checks, it became clear that the material did not change during the entire period of operation.

It follows from this that the growing popularity and steady increase in the consumption of expanded polystyrene is a regularity. Over the past 20 years, its use has increased tenfold. The main consumers of this material are Europe and North America.

Extruded polystyrene foam for insulating a monolithic base plate is a material with a uniform structure, consisting of closed cells. Due to the low density of the material, its thermal insulation properties increase. You should also know that expanded polystyrene has increased strength characteristics and is able to withstand quite heavy loads.

Expanded polystyrene practically does not allow water to pass through and is not afraid of the effects of chemically aggressive environments. Thermal insulation with this material is done in regions with harsh winters and very cold weather. Expanded polystyrene copes well with repeated cycles of freezing and defrosting, while its operational characteristics do not change at all. Expanded polystyrene is usually sold in the form of slabs.

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Why polystyrene and not another material?

A site for the foundation is marked.
A layer of soil is removed from above. The depth depends on the construction project. When removing the soil, you must try to make the bottom as even as possible. For this, the last 0.2 - 0.3 m is removed by hand. A layer of sand is poured onto the prepared site and then rammed.
Temporary formwork is being installed, and a concrete base is being prepared. The formwork is poured with a small layer of concrete. Base reinforcement is not required.
After the concrete has hardened, begin laying expanded polystyrene plates, in this case, it is necessary to align the mounting grooves and try not to leave large gaps.
A polyethylene film is placed on the laid layer of insulation. The joints are glued with tape. Polyethylene creates a waterproofing layer. In addition, the film prevents concrete leaks between the joints of the insulation slabs.
Formwork and reinforcement cage construction is in progress. Concrete is being poured.
After complete drying, the formwork is surveyed.
The side walls are additionally insulated with expanded polystyrene.

A few tips:

work starts from any corner of the foundation;
the slabs must be laid from bottom to top with an offset of the rows, that is, something should look like brickwork;
at a height approximately equal to the width of the slab, pull the rope. The horizontal tension is checked using a building level;
the first row of the heat-insulating layer is laid. This is done so that the subsequent rows of plates do not diverge, otherwise all the insulation will become simply useless.

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How to properly mount polystyrene foam plates on walls?

The foundation wall is covered with spread mastic. Then expanded polystyrene is attached to it and tightly pressed. All plates of the row are mounted in the same way.

When carrying out work, it is necessary to carefully monitor the connection of adjacent slabs. It should be clear, without gaps and be in the lock.

The joints on the ridges of the locks are cut off at the corners. If necessary, the joints are additionally filled with polyurethane foam.

As the high rows are laid, the lower ones are covered with soil. Such actions facilitate the work and help to press the material.

Plates located below ground level are glued only to the mastic.

This is to prevent damage to the waterproofing.

Insulation located above the ground can be additionally strengthened with dowel nails (umbrellas). All this can be easily done with your own hands, you just need to be very careful. To fix the base on the walls, holes are drilled using a punch. Umbrellas are fixed in the center and at the junctions of adjacent slabs.

The foundation insulated with expanded polystyrene is so popular for the following reasons:

when using this technology, you can save up to 40% of money;
reduction of heat loss reaches 20%;
the waterproofing layer of the foundation will last 2 times longer;
expanded polystyrene guarantees quality and long service life;
slabs reliably protect the waterproofing layer, ensuring the drainage of accumulated groundwater.

From the above, it becomes clear that, insulated with expanded polystyrene, it will serve for a long time, and the house will be cozy, comfortable and warm. In addition, the material is absolutely safe from an environmental point of view and has a low cost, which clearly tilts the choice in its direction when long-term construction is ahead.

Insulation technology for slab foundation. Thermal insulation of the foundation slab - materials and options for heat saving Thermal insulation of a monolithic slab with expanded polystyrene

Insulation of foundations

Foundation insulation material: Penoplex

How to insulate: inside or outside?

Penoplex insulation during the construction phase

Swedish foundation

Advantages of an insulated foundation

Thermal insulation of the foundation slab: the order of work

general information

Advantages of a slab foundation

Advantages of slab thermal insulation

Disadvantages of slab foundation

Insulation materials

Insulated plate installation

Site preparation

Insulation of the slab

Heating pipes installation rules

Insulation under the foundation slab: step by step instructions

The advantages of insulating a slab base

Materials for insulating a monolithic slab foundation

Insulation of a monolithic foundation slab from the inside

What does foundation insulation give?

What kind of insulation to use for the foundation?

Polyurethane foam

Extruded polystyrene foam

Extruded polystyrene foam with grooves

Insulation of the foundation with expanded polystyrene

Insulation of the foundation with polyurethane foam

Insulation of a monolithic foundation slab with expanded polystyrene

The choice of insulation

Outdoor insulation technology

Internal insulation technology

Insulation of the body of the foundation slab

Insulation of the slab foundation - Technologies, subtleties, nuances

Warming methods

Benefits of timely insulation

What materials can be used to insulate a slab foundation?

Insulation rules for slab foundation structures

Carrying out insulation measures during construction

Advantages of USB, as well as of all slab foundations

Disadvantages of USB and all slab foundations

ADVANTAGES SPECIFIED FOR USHP

VALIDITY OF THE USHB FOUNDATION

Insulation of foundations

Foundation insulation material: Penoplex

How to insulate: inside or outside?

Penoplex insulation during the construction phase

Swedish foundation

Advantages of an insulated foundation

general information

Advantages of a slab foundation

Advantages of slab thermal insulation

Disadvantages of slab foundation

Insulation materials

Insulated plate installation

Site preparation

Insulation of the slab

Heating pipes installation rules

Insulation of the foundation of a monolithic type with expanded polystyrene

Why polystyrene and not another material?

How to properly mount polystyrene foam plates on walls?