Insulation of the foundation slab. Features of insulation of a monolithic foundation slab? Internal insulation technology

To begin with, the location of the foundation for the building is marked on the building site.
The top layer of continental soil must be removed to the depth of laying the foundation slab, the bottom of the excavation must be as smooth as possible.
The prepared area is filled with coarse sand, which must be compacted using vibrating rammers. A small layer of concrete is poured over the layer of sand, for which it is exposed.
After the concrete screed has hardened, lay out the insulation from polystyrene foam boards, making sure that the mounting grooves match as much as possible. Large gaps should not be allowed between the insulation boards.
A layer of polyethylene film is laid on top of the laid polystyrene slabs, which is glued together using special tape.
Construction formwork is erected for pouring a slab base, into which a spatial frame made of reinforcement with a diameter of 10 mm is mounted. Concrete is poured from the corner of the slab foundation, evenly leveled and compacted using a vibrator.
The foundation slab gains strength in about 28 days, the formwork can be dismantled two weeks after the structure is poured - by this time the foundation has gained up to 70% strength.
The side walls of the foundation slab are additionally insulated with expanded polystyrene slabs.

An insulated monolithic slab will last long years without structural damage from exposure to unfavorable factors.

When choosing a foundation, they are guided firstly by reliability, and secondly by cost. It would be nice if both qualities were combined, but this is not always possible. One of the most reliable foundations for building a house is a monolithic slab foundation. In some cases - on normal soils for light houses it is relatively inexpensive, but in difficult cases it can be expensive.

Scope and types

A monolithic slab for a house belongs to floating, non-buried foundations; it can also be shallow. It got its name due to the fact that a reinforced concrete base is poured under the entire area of the house, forming a large slab.

A prerequisite is the presence of a sand and gravel cushion, which redistributes the load from the house to the ground and serves as a damper during frost heaving. Often such a foundation is the only possible solution. For example, on unstable, loose soils or on clays with a large freezing depth.

The monolithic slab foundation design is simple and reliable, but its manufacture requires a large number of reinforcement and large volumes of high-grade concrete (not lower than B30), because the entire area occupied by the building is reinforced and concreted, and with a margin - for greater stability. That’s why such a foundation is considered expensive. In principle, this is true, but it must be considered. In some cases, its cost is lower than deep strip laying - due to less excavation work and less concrete.

Laying depth monolithic slab determined depending on the weight of the house and the type of soil. With shallow depth on heaving soils in winter, the house along with the base can rise and fall. If the reinforcement and slab thickness are correctly calculated, this does not affect the integrity of the building. The plate compensates for all changes due to elastic force. In the spring, after the soil has melted, the house “sits” into place.

There are four types of slab foundations:

Classical. A reinforced concrete slab is placed on a sand and gravel bed with or without insulation. The thickness of the concrete layer is 20-50 cm, depending on the soil and the mass of the building. The thickness of the layers of the cushion depends on the depth of the fertile layer - it must be completely removed. The resulting pit can be filled 2/3 with sand and gravel.
Insulated Swedish stove (USH) with built-in heated floor. Firstly, it differs in that the slab formwork is permanent - made of L-shaped polystyrene foam blocks. This significantly reduces heating costs - heat loss is minimal. Also, heated floor pipes are laid on top of the insulation, reinforcement is laid on them (sometimes under them), and everything is filled with concrete, the thickness of the concrete layer is 10 cm. All communications, including water supply and sewerage, are laid at the stage of preparing the foundation - in a sand cushion. That is, after making the foundation, the heating system is ready and the engineering systems are connected. This approach allows you to speed up construction, but the foundation itself is expensive. This type of foundation requires competent engineering calculations and the same execution: you cannot make mistakes when calculating and laying communications, since alterations are impossible. Questions also arise regarding the repair of systems immured in the foundation. It is impossible, so they use expensive materials with a long warranty.
USHP - insulated Swedish stove with built-in heated floor
Russian - a plate with stiffening ribs. To strengthen the structure for heavy houses and in difficult operating conditions (severe frost heaving), Russian scientists came up with the idea of making more massive stiffeners. They are usually arranged under load-bearing walls. In this case, the complexity of the work increases - the stiffeners are installed separately, and the slab separately. But the bearing capacity of such a foundation is much higher, which makes it possible to reduce the thickness of the slab to 10-15 cm.

Construction technology of insulated slab

Energy saving is becoming a really hot topic, so few people build foundations without insulation anymore. Any slab foundation is a multi-layer structure, and in the case of insulation there are even more layers. To achieve the desired level of quality, each level must be carefully completed. Let's look at each in more detail.

Preparing the base

The dimensions of the pit for the monolithic slab must be at least 1 meter larger than the building itself. In this area, the fertile soil is completely removed. Its thickness varies in different regions - from 20-30 cm to 50 cm and more. In any case, everything is removed.

Along the edge of the pit, just below the general level of the bottom, they are laid drainage pipes, discharging surface water into drainage wells. This measure is necessary so that the walls and the foundation itself do not get wet.

The bottom is leveled, the holes are filled in, the humps are removed, everything is carefully leveled to the horizon level and compacted. Roll out onto a leveled bottom. It should cover not only the bottom, but also the walls. The canvases are spread with an overlap, the edges are glued together with reinforced tape. Geotextiles prevent plant roots from germinating and also prevent sand, which serves as a damping pad, from being washed away.

Clean, medium-grain sand is poured onto the laid geotextile. A layer of sand is 20-30 cm. It is poured thin layers, evenly distributed and compacted layer by layer. The layer of sand that can be properly compacted with a manual vibrating plate is 8-10 cm. These are the layers that sand is laid in. It must also be laid level, in an equal layer throughout the entire pit.

The thickness of the layer can be controlled using stretched cords. They are tied to driven stakes, specially made supports - benches, to formwork installed in a level (see photo below). All cords must be in a horizontal plane. Knowing the initial distance from the bottom of the pit to the tensioned threads, you can determine the height of the poured layer.

Crushed stone is poured onto the compacted sand. Fill the entire volume at once, distributing it evenly over the site. The leveled crushed stone is compacted to a high density.

At this stage, sewer and water pipes. Ditches of the required depth are dug in the already compacted crushed stone. They should be such that there is some space around the embedded elements. Pipes are laid in the ditches, filled with sand, leveled, and the sand is compacted with a shovel or board. More severe compaction may lead to cracks. That’s why the pipes are laid after compaction.

Concrete preparation

Formwork is placed around the perimeter of the pit. It is usually assembled from 40 mm thick boards or 18-21 mm plywood. The height of the formwork for a monolithic slab is the total thickness of the remaining layers. Along its edge it is convenient to control the level of concrete when pouring, so the board must be edged. To save material, you can set up the formwork only for preparation. After the concrete has set, it is dismantled and placed higher, reused to fill the main slab. But the loss of time with this approach is significant, so this is not always done.

In any case, the formwork is supported from the outside with stops and jibs. The structure must be rigid to support the mass of concrete.

A 100 mm layer of concrete is poured onto the compacted gravel. This can be low grade concrete - B7.5 - B10. Concrete preparation will be a reliable basis for laying waterproofing and insulation, and also serves to more evenly distribute the load from the house.

Waterproofing

Since the monolithic foundation slab is completely in the ground, it needs careful waterproofing. Therefore, two types of materials are usually used: coating and roll. The base is first thoroughly dust-free, then impregnated with diluted kerosene or solvent primer (and the sides of the concrete preparation are also coated). It is sold very thick and does not adhere well to concrete. As a result, the roll waterproofing adheres poorly and the foundation will get wet. When diluted, it becomes more fluid and penetrates deeper into the concrete. At the same time, it almost does not lose its properties.

When laying out rolled waterproofing, it is released 10-15 cm beyond the foundation. The panels are rolled out with an overlap, the connecting edges must be coated with bitumen mastic and pressed well. When laying out, you need to make sure that there are no creases or waves.

If the groundwater level is high, two layers of roll waterproofing may be needed. It is then rolled out crosswise and also glued onto a primer ( bitumen waterproofing), but you can no longer breed.

Double waterproofing of a monolithic foundation slab - coating and roll

From rolls waterproofing materials Gidroizol and TechnoNIKOL Technoelast EPP-4 on high-density polystyrene performed best. Tekhnolnikol has this brand high strength the breaking strength is about 60 kg, which increases the chances that it will not be damaged during further work. You shouldn’t use roofing felt, no matter how much you want to save money. In its modern version, it is too thin and brittle and quickly loses its properties. You cannot replace the waterproofing in the slab, so use the best material.

Capillary suction of moisture through the slab can also be reduced using liquid impregnations such as Betonite. It significantly reduces moisture absorption. Penetrates to a depth of 50-60 cm, so it saturates the concrete preparation through and through. The disadvantage of this material is its high price, but the properties of the material are excellent.

Insulation

To insulate the slab foundation, high-density extruded polystyrene foam is used. The thickness of the insulation layer is 10-15 cm, depending on the region (for the Middle Zone 10 cm is enough). Laying is carried out in at least two layers, overlapping the seams that form cold bridges. This requires more time, but heating costs will be lower. If the slabs have an L-shaped lock, they can be laid in one layer.

Since polystyrene foam is “not friendly” with petroleum products, a thick sheet of paper is spread over it. plastic film, and then the heat-insulating material is laid.

Reinforcement

For the reinforcing frame, ribbed reinforcement of class AIII, with a diameter of 12-14 mm, is used. It is laid lengthwise and crosswise, in increments of 15-30 cm, and can have one or two layers. It all depends on the type of soil and the mass of the building. All reinforcement parameters are calculated separately.

The reinforcement must be at a distance of at least 5 cm from the edge of the slab. Therefore, it is placed on special supports that provide the required clearance.

When reinforced, a cage is obtained; at each intersection, the rods are tied together with a special soft steel wire. There are also connection techniques - using plastic clamps or welding. Plastic clamps They connect quickly, but not everyone trusts them. It is not recommended to use welding, because the weld seam is the most vulnerable place to rust, and the connection is too rigid. When using wire and clamps, the entire structure can “play” a little without destroying the ligament, and when welding, such movements lead to the seam bursting. As a result, the reliability of such reinforcement is low.

Pouring the foundation slab with concrete

The thickness of the slab is calculated for each specific case and can be from 20 cm to 50 cm. When pouring, use concrete of at least grade B30. The entire perimeter must be filled in one day, avoiding the appearance of vertical seams. Therefore, for concreting a slab foundation, ready-made concrete is most often delivered: large volumes are required within a certain period of time.

The arrival schedule of the vehicles must be calculated so that you have time to distribute the first portion and compact it. For compaction, construction deep vibrators are used, which create high-frequency vibrations. As a result, all air is removed, the concrete mixes better, becomes more fluid and plastic. The result of this treatment is not only a smooth concrete surface, but also a higher hygroscopicity class.

As a last resort, you can fill the slab in horizontal layers. Vertical division in this case is unacceptable, since cracks are likely to appear at the joints.

Curing

For the normal process of concrete hardening, a sufficient level of humidity of 90-100% and temperatures above +5°C are required. It is advisable to fill the slab in warm weather with a temperature of about +20°C. This temperature regime is optimal for the hardening process. Caring for concrete monolithic slabs consists of preventing mechanical damage and maintaining moisture.

Immediately after laying, the concrete is covered with a diaper or tarpaulin. This prevents it from heating up from the sun, and the wind does not affect it. The film is glued into large panels. The strips are laid with an overlap of 10-15 cm and taped with tape. It is desirable that there be as few unlined joints as possible, that is, the shelter should consist of one or two pieces, if one is too inconvenient. In this case, individual pieces of film overlap each other by at least half a meter.

The dimensions of the film are such that the side surface of the formwork is also covered, and a load can be placed on the edges of the film, which will prevent the wind from lifting it. Also, with a load - boards - they press the place where the two panels overlap to reduce windage; they can be spread out on the surface.

If the air temperature is above +5°C, approximately 8 hours after pouring, the concrete is watered for the first time. Irrigation should be drip, not jet. To avoid damaging the surface with drops, you can lay burlap on it or sprinkle a layer of sawdust and cover it with film on top. The covering material is watered, and it maintains the moisture content of the concrete. In any case, watering is carried out only at temperatures above +5°C.

If there is a threat of frost, the slab and formwork are additionally insulated. You can use any heat insulating materials, both prepared for building a house, as well as sawdust, straw and other available materials.

When to remove formwork

Differences between an insulated monolithic Swedish slab and a video about its construction

As mentioned earlier, the insulated slab under the house developed by Swedish builders is energy-saving. During its construction it is used permanent formwork from extruded polystyrene foam. As a result, heat leakage into the ground is minimal. The second fundamental difference is the water heated floor system built into the slab.

Since engineering systems are poured deep into concrete, it requires accurate and competent calculations. High demands are also placed on execution. Even small mistakes are critical. You can make USP yourself, but it is better to order the project. For an approximate cost breakdown, see next photo. The amounts are no longer relevant, but the percentages are correct. The cost of the foundation project is about 1%.

IN next videos you will see the stages of manufacturing a Swedish stove for a specific house. Many useful devices are described that will make work easier, and explanations are given for some of their features.

And look how the Germans pour such a slab. There are also many useful nuances.

Insulation is an important part of any construction. It is necessary to insulate all external parts of the building from heat loss: walls, roof, basement and foundation. Insulating the base of a building not only limits heat loss, but also prevents frost heaving of the soil. How to insulate a monolithic foundation? 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 top of the foundation wall are covered with insulation. In addition, heat-insulating slabs are laid under the external blind area around the buildings. These measures help protect the soil and walls from freezing and, therefore, avoid frost heaving of the ground around the house.

Different foundation designs have different insulation methods. Deep strip - only vertical walls near the surface of the ground are insulated, shallow strip - walls and the sole. The pile foundation rests on non-freezing soil, so only the side surfaces of the piles are insulated.

Insulation of a monolithic foundation slab is carried out from the sides and bottom. This is necessary due to the location of the slab in the soil freezing zone. 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

Foundation insulation is subject to increased requirements for moisture and water resistance. It comes into contact with wet soil, so in addition to insulation it must prevent moisture from penetrating into the walls of the house. In addition, the foundation insulation must withstand compressive loads.

Ideal material for foundation insulation - extruded polystyrene foam. The trade name of the material is penoplex. It has a closed cell structure, so water and moisture do not penetrate into the material and cause its destruction. Temperature fluctuations around zero create a variable “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 polystyrene foam (foam plastic) is not used in foundation insulation. Can only be used moisture-resistant types insulation: PPU 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 ordinary polystyrene. But it pays off in durability.

How to insulate: from the inside or the outside?

How to properly insulate a 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 placement of the insulation inside the wall does not protect the wall and the slab, but it allows you to improve the microclimate in the room. This means that external insulation is the best option for any building surfaces.

However, insulation from the outside is not always possible. So for the foundation, external insulation is possible only at the construction stage. Afterwards, the base can only be insulated from heat loss from the inside.

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

If the insulation of the slab was done 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 at the construction stage

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

To eliminate uneven pressure of the foundation on the ground, part of the soil is removed and backfilled with gravel and then sand. A layer of sand is spilled with water and compacted thoroughly.
After this, a layer of waterproofing and insulation boards are laid.
Reinforcing 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 bottom row is supported by plastic beacons (so that after pouring the reinforcement is inside the concrete).

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

Swedish foundation

The foundation, insulated from below with polystyrene slabs and equipped with warm pipes, is called Swedish. The abbreviation for the foundation sounds like “USHP” or Insulated Swedish Plate.

The thickness of the base slab 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 above the soil freezing line. In this case, frost heaving is brought under control and compensated for by external insulation of the slab.

Additional heating arrangement allows you to get a foundation and a warm floor for 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 a third. Construction costs are reduced.

Advantages of an insulated foundation

Let us list the advantages of insulating the foundation slab necessary element construction:

Saving concrete, reducing construction costs.
Acceleration of house construction time.
Reducing heat loss and reducing utility bills.
Improving the indoor microclimate.
Increasing the durability of the foundation slab and the entire structure.

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

rfund.ru

Insulation of the foundation slab: work order

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

general information

The design of the slab base consists of layers:

geotextile is covered with overlapping strips on the sand layer, the joints are taped;
pour crushed stone in a layer of 15-20 cm;
pour a leveling layer of cement mortar, 5-10 cm thick;
be sure to isolate the structure from moisture using rolled or coating materials;
arrange a heat-saving layer;
cover with plastic film in stripes overlapping by 20 cm;
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 to a great depth and significant deepening is required strip foundation, the installation of the slab will be cheaper and less excavation 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 entire house along with it move simultaneously with the soil;
the slab can be mounted on any type of soil, even on peat bogs and marshy areas;
the slab is erected above the soil freezing level, thanks to the sand cushion, frost heaving has virtually no effect on the structure;
reinforced concrete slab is not subject to shrinkage;
suitable for the construction of buildings up to 3 floors.

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

Advantages of slab insulation

As thermal insulation material Expanded polystyrene, polystyrene foam, and polyurethane foam are used. Mineral wool is not suitable due to its low strength and high degree moisture absorption.

There is a technology for installing a Swedish stove. The main difference is that concrete structure It is built 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 stove are:

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

A drainage system consisting of pipes for draining rain and melt water is provided around the building.

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

Disadvantages of a slab foundation

A slab foundation is not always the best option. Always do everything in advance necessary calculations and select the most suitable type of foundation for your home.

Disadvantages of the stove:

not suitable for construction on sloped areas;
to build a house with a basement on a slab, you need to dig it to a great depth, this will be very expensive;
it is difficult to repair communications carried out under the foundation slab;
during construction in winter you will need additional expenses to heat the concrete and maintain the required temperature in the area.

A slab foundation is erected only when it is impossible to install a strip foundation.

Insulation materials

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

No. Thermal insulation material Characteristics

1	Styrofoam	Consists of cells filled with air. Available in the form of sheets, it has insufficient density, so its surface needs additional protection.
2	Extruded polystyrene foam	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 laid out so that the seams of the sheets of the first and second row do not intersect. During installation, provide 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, resulting in a dense, solid foam that is applied to the surface. The slab insulated with polyurethane foam has high thermal and sound insulation properties and can withstand moisture. Refers to low-flammable materials, and some brands are difficult to burn.

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

Installation of insulated slab

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

Insulating a slab foundation allows you to save significant money on heating the room during operation.

Site preparation

At the creation stage of the project, it is necessary to take into account that the area for the foundation slab must be wider than the house building by at least 1 m on each side.

Instructions for performing preparatory work:

The site where construction is taking place is cleared of debris and the root system of trees and shrubs.
Mark the position of the slab according to the design.
The fertile layer of soil is cleared and removed. The degree of slab burial depends on geological and climatic conditions. Most often, the thickness of the slab varies from 20 to 30 cm, less often the base is buried by 50 cm.
They dig a pit and manually level its bottom and side walls.
Pipes are installed around the perimeter to drain rain and melt water.
Geotextiles are laid out in overlapping strips. The material should cover the bottom and extend to the entire height of the walls.
Drive in wooden stakes or metal rods. Pull the cord strictly horizontally. It will serve as a guide for uniform filling of sand and crushed stone.
Pour sand 20-30 cm thick. Distribute the sand evenly over the entire area, moisten it with water and compact it well.
Lay out geotextiles.
Pour crushed stone, distribute it evenly around the perimeter, and compact it thoroughly.
Conduct all necessary communications. They dig trenches under them in the rubble a little wider than the cross-section of the pipes. The pipeline is laid and a layer of sand is poured on top.
The sandy surface is leveled.

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

Insulation of the slab

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

Mount removable formwork from boards, install supports so that the structure does not fall apart under the weight of concrete.
A layer of concrete 50 mm thick is poured.
After the cement mortar has completely hardened, sheets of penoplex are laid on it close to each other 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 sufficient. The joints of the row are placed in a checkerboard pattern, offset by 1/3. When laying in two rows, the joints should not intersect.
Spread thick polyethylene in overlapping strips. The joints are sealed with tape.
The reinforcement frame is laid and the formwork is filled with concrete.

After the slab has dried, the formwork is dismantled, the side walls are thermally insulated with the same material that was used to lay it under the slab.

The insulated base helps to increase heat saving indoors.

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

Rules for installing heating pipes

When installing USHP, heating pipes are used. There are the following rules for their installation:

More dense pipe laying allows you to get more high temperatures heating the room.
The distance between external walls and pipes should not exceed 150 mm. Closer to the center, the laying step can be increased 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 junction of monolithic slabs. In this case, it is better to lay two circuits. The pipeline crossing the joint is insulated with steel sleeves 30 cm long.

How to make an insulated Swedish stove with your own hands can be seen in the video: An insulated foundation slab allows you to reduce heating costs during operation and helps reduce the level of frost heaving in 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

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

A layer of horizontal insulation can reliably isolate the foundation slab from the zone of frost heaving, contact with soil moisture and prevent freezing.

Advantages of insulating a slab base

Horizontal slab insulation

High-quality insulation of a monolithic foundation slab guarantees the durability of the building and long-term operation without the need for unplanned repair work. Particularly relevant is the insulation of 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 on heating a residential building, real heat saving mode.
Preventing the formation of condensation that can destroy the building structures.
Improving living comfort.
Temperature stabilization interior spaces exploited residential building.

Materials for insulating a monolithic slab foundation

fundamentaya.ru

Insulation of a monolithic foundation slab from the inside

Insulating the slab of any foundation is one of the most important things when building a house. This is best done in the warm season, and should not be done in rainy weather. Insulation of a monolithic foundation slab is especially important for cold regions where the soil freezes at great depths. When heaving soils freeze, they 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 heat loss throughout the entire future building and preserve its durability.

What does foundation insulation provide?

The better all the work is done, the longer and more reliably the building will last. And most importantly, the house will remain warm even in severe frosts. Do not forget that most of the cold enters the house through the foundation. And if the building has a basement (billiard room, gym), then care should be taken about internal insulation. This is especially important if the basement is not heated. But the most important thing is external insulation any residential building.

The main reasons why insulation is necessary:

Increasing waterproofing properties.
Reduced heat loss.
Reducing home heating costs.
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 lifespan.

What insulation should I use for the foundation?

The most important part of the job when insulating a new foundation slab is required is selecting the appropriate material. It should not deform under soil pressure and absorb moisture. These are the most important parameters of any thermal insulation. Soft materials such as mineral wool are not suitable. The best option is polyurethane foam and extruded polystyrene foam. They both have excellent thermal insulation characteristics and a fairly low cost, which is also important during construction.

Polyurethane foam

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

This material has a number of positive properties:

low thermal permeability;
good adhesive properties;
reliability;
durability.

And the main thing is that when using polyurethane foam, there is no need to use additional means for steam, water and waterproofing. It 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 appropriate equipment.

Extruded polystyrene foam

This type insulation costs significantly less than polyurethane foam and is easier to install. This material consists of plates that do not allow or absorb moisture. He keeps his for a long time thermal insulation properties even in cold regions. Advantages of extruded polystyrene foam:

high strength;
long term services;
reliable thermal insulation properties.

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

Extruded polystyrene foam with grooves

This is a new type of insulation. Milling grooves on the surface of polystyrene foam slabs are excellent for insulating the foundation. Used in conjunction with geotextile fabric as fastener drainage. Its main properties:

good thermal insulation;
protective layer waterproofing;
waterproof.

Foundation insulation with polystyrene foam

To insulate a monolithic slab, you can use both polystyrene foam 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 waterproofing, then you can begin laying extruded polystyrene foam slabs.

Most effective method insulating the foundation with this material means using it in zones of soil freezing. The insulation is installed to the freezing depth. This is quite enough. Special attention when insulating, it is worth paying attention to the corners: in such places, the polystyrene foam used 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 insulation under the blind area structure.

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

Insulation of the foundation with polyurethane foam

When insulating a monolithic foundation using polyurethane foam, it is important that there are no breaks 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 entire 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 approximately 15 mm thick.

Upon completion of all work, the foundation is waterproofed and covered with soil. Equipment for installing such insulation can be purchased in specialized stores or rented. But it’s easier and faster to use the services of professionals.

rfund.ru

Some effective construction technologies have been recently developed. This is explained by the appearance on the market of new materials with better or unique characteristics. Some of these techniques can be reproduced an ordinary person after relatively little study of the relevant materials. In this article we will look at the insulation process with my own hands the foundation of a private residential building or other relatively small building.

Why you may need to insulate a foundation slab

Improving the insulation parameters of a building will simplify and make its operation cheaper. This fact alone is enough to think about carrying out the appropriate work. Energy resources, despite temporary market fluctuations, will always have high value. By reducing their consumption, you can count on significant savings.

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

Separately, it is necessary to consider soil heaving. It occurs in winter. These mechanical impacts can create 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 with examples that confirm the feasibility of its use. In this case, you should pay attention to the “insulated Swedish slab” 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 stiffeners. It is installed on a cushion and surrounded by polystyrene foam boards.
Sand is initially poured under the main insulation and on the sides of it.
A system for collecting water and discharging it into drainage is pre-installed.
The blind area along the contour reduces the load on the drainage complex.
Providing comfortable temperature conditions produced using a “warm floor” system. It is built into the foundation at the stage of its creation.

This name itself determines 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 time frames are quite sufficient for valid conclusions. Practical tests confirmed the presence of the following features:

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

Material for creating a high-quality insulating layer

You can make a choice based on analogues of materials that are used in Swedish technology. But first, let’s rule out unsuitable options:

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

Using the method of elimination, we found the “winner” of this correspondence competition. This is factory-produced foam polystyrene, penoplex. We list below those characteristics of the material that will be useful for solving the tasks:

Its production method involves the production of standardized products. Thus, if you purchase penoplex from a well-known brand, you can be sure that each slab will have the same parameters.
Precise dimensions and low weight will facilitate transportation, storage, and installation operations.
The uniform distribution of closed bubbles in the penoplex structure provides excellent thermal insulation properties. To fully insulate a monolithic foundation, you do not need to create a layer that is too thick.
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 slab foundations

We have found out the main parameters of this technique, so we can proceed to the description of the working operations. Let's look at the steps that are used to insulate a foundation slab:

For this group of works, it will be enough to create a layer of high-quality penoplex with a thickness of no more than 10 cm. It can be formed from two rows of slabs, which are laid 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 and soil characteristics. When creating a recess, the bottom must be made level, so it is recommended to use manual labor in the final stages.
Sand is backfilled and compacted, after which temporary formwork is installed, and the first layer of concrete is poured without reinforcing elements.
When the base has hardened, foam boards are laid on it in the order indicated above. They are covered on top with thick plastic film. The seams between the individual strips are carefully sealed with wide tape.
Next, the main foundation is created from reinforced concrete.
After it hardens, attach to the end parts adhesive composition foam boards.

mynovostroika.ru

Insulation of a monolithic foundation slab with polystyrene foam

It is difficult to build a solid foundation on unstable soils. In such cases, a slab base is used. It acts as a shallow foundation, drifting across the site as soil masses move. Since the entire structure moves, no destructive stresses arise.

For proper operation This type of foundation requires protection from freezing. Insulation of a monolithic foundation slab:

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

Choice of insulation

Not everyone, even the most efficient material, suitable for working in or near the ground. When choosing a material you need to be guided by:

moisture-proof. When saturated with water from the soil, 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 noticeable pressure on the material. It is especially noticeable on 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. Groundwater may contain increased concentrations of salts. All these factors lead to premature destruction of the insulation.

When installing insulation inside a building, the material must be non-flammable. If there is a possibility of fire, it should not be released harmful substances which may cause suffocation.

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

Often, extruded polystyrene foam is used for zero-cycle work. Insulating the foundation slab with expanded polystyrene, done according to all the rules, allows you not to worry about the safety of concrete and heat conservation.

Characteristics of expanded polystyrene

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

outside;
from the inside;
in the body of concrete

External 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, basically, insulation is attached precisely to the side surfaces.

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

Waterproofing occurs by applying bitumen mastic or melting paraffin on the surface and edges of the slab. The second method is more economical and reliable. Using a gas burner, pieces of paraffin are melted. The material is evenly distributed over the surface, absorbing into it.

Waxing closes the pores of concrete, creating a barrier against moisture. Complete adhesion helps prevent insulation peeling. This means that insulation can be easily attached to it.

Expanded polystyrene boards are mounted on glue or on cement-sand mortar. The first option allows for insulation at sub-zero temperatures. The underground part is secured only by gluing. This is necessary to avoid violation of the hydraulic barrier.

The base part of the insulation of the slab foundation with polystyrene foam is additionally fixed with plastic dowels. To do this, holes are drilled through the glued plates. They go through all the insulation and part of the foundation.

The glue is applied around the perimeter of the slab and in several stripes in the center. Wait for 1 minute and press the plate against the surface for a couple of minutes. After gluing, the bottom plates are sprinkled with a layer of sand. This helps secure them in the mounting position.

The second row of insulation is installed with offset seams. It is advisable to bandage the horizontal joints as well. This helps to avoid the occurrence of cold bridges.

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

Fixation with umbrellas is carried out at five points on the slab. The dowels are installed after the slabs are completely glued, but no later than three days later.

After installation, the seams are sealed with foam. Excess foam is cut off and the surface is plastered over a 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:

On top of the stove;
In the body of concrete.

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

waterproofing is installed along the foundation slab, extending onto the wall;
logs are screwed on top of the waterproofing layer;
a layer of insulation is placed between the logs;
a waterproofing film is attached to the joists on top of the insulation;
a plank base, plywood or OSB boards are mounted on the film;
A backing made of cork, foamed polyethylene or pine needles is laid on top of the subfloor. The finishing floor is mounted on it.

You can do without lag. In this case, the slab foundation is completely insulated with polystyrene foam. The material is laid in a continuous layer. The underlay and finishing floor covering are laid immediately on top of it.

When installing in concrete, the following work is performed:

the base plate is waterproofed;
An insulation layer with a thickness of at least 100 mm is installed. It is better to use products with a locking connection system;
PVC film with a density of at least 1.42 g/cm3 is laid on the insulation;
fits reinforcement mesh. Its role can be played by a masonry mesh with a cell of 100*100 mm;
the surface is filled with a screed no thinner than 5 cm;
The finishing coating is laid over the screed.

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

Insulation of the foundation slab body

Warm concrete is used in many areas of construction. It can be purchased in the form of already ready mixture or manufactured on site. For preparation, add to the initial mixture to form the foundation slab. granulated polystyrene foam.

Polystyrene concrete with a density of D1200 is used for constructing structural elements. When preparing 1 cube, the composition includes:

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

When creating such concrete, you need to remember about shrinkage. It is 1 mm per 1 m of surface. The slab needs to stand for some time after gaining strength. It is necessary to arrange a leveling screed on 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 slab 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, unlike plain concrete.

The choice of type and technology of foundation slab insulation depends on design features buildings and construction sites. It is worth choosing the optimal solution based on the data of thermal engineering calculations and comparison of the estimated cost.

tstinfo.ru

Insulation of slab foundations - 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 monolithic foundation slabs, which can be built on various types soil. But concrete has high thermal conductivity, so developers need to take care of insulating load-bearing structures during the construction process.

Insulation methods

Insulation of a slab foundation must be carried out in the part that is located in the soil freezing zone. The developer should lay insulation under the foundation slab, as well as under the external blind area, which must be created around the building. And also the basement of the building and the upper part of the foundation wall must be covered with special material. Timely insulation of a 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 in the house.

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

Tape (in-depth). For insulation, various materials are used, 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 side surfaces of piles buried in the soil are subject to insulation.
Monolithic tile construction. The foundation slab is insulated not only from below, but also from the sides.

Advantages of timely insulation

An insulated slab foundation has a large number 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.
An insulated foundation allows you to minimize heat loss. This has a positive effect on the indoor microclimate, as well as on bills public utilities, which rapidly increase in the winter season.
The timing of construction work is being accelerated.
The useful life of the supporting structure is maximized, since it is no longer subject to the harmful effects of moisture and low temperatures.
An insulated foundation slab prevents condensation from forming on interior walls ah premises.
The service life of waterproofing materials, which are used in the process of constructing slab foundation structures, is maximized.

What materials can be used to insulate a slab foundation?

Currently, the domestic construction market offers a huge range of materials 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 foundation structures using special equipment. Components entered into chemical reaction, already on concrete surfaces form a durable foam that hardens almost instantly. This material helps to minimize heat loss, prevents the penetration of extraneous noise from the street into the premises, does not undergo putrefactive changes with constant contact with a damp environment, and is highly resistant to fire.
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 requires additional lining.
Extruded polystyrene foam. This material has a fine-cell structure and is supplied to the construction market in the form of rectangular sheets. It has excellent technical properties and is able to withstand high loads without changing either the internal structure or geometric shape. IN last years When insulating slab foundation structures, developers use extruded polystyrene foam, since it does not require additional protection and can perform its functions for decades.

In recent years, many developers prefer to insulate 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 come into contact with a damp environment for many decades, insulating the foundation with penoplex will 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 penoplex 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.

Rules for insulating slab foundation structures

Before insulating a 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 penoplex from the outside, this will protect not only the slabs, but also the walls from freezing. In the case when polystyrene foam panels are laid on the inside 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. It follows from this that external insulation of the foundation with penoplex will be ideal option for any construction projects.

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

Carrying out insulation measures during the construction process

The procedure for insulating 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 concrete slab will be created. Its depth should be 1 meter. Recesses are made at the bottom into which drainage pipes are laid, the functions of which are to drain 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, geotextile, is rolled out on its surface. 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 crushed stone is laid on top of the geotextile. Thus, a sand-crushed stone cushion (approximately 30-40cm thick) is created at the bottom of the pit.
Utilities, such as water and sewer pipes, are laid. After laying them, the surface is sprinkled with sand and leveled.
Formwork is constructed around the perimeter of the prepared pit. For these purposes, it is customary to use boards or sheets of moisture-resistant plywood. From the outside, the formwork must be supported with jibs or stops so that the wooden structure can 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 hardens, the developer must begin carrying out waterproofing and thermal insulation measures.
Due to the fact that the monolithic concrete slab will constantly be in the ground and in contact with a humid environment, the developer must provide it with high-quality waterproofing. For these purposes, in the construction industry it is customary to use rolled or coating material. The concrete base must be thoroughly cleaned of debris and then removed from dust. To increase its adhesive properties, it is recommended to treat it with diluted kerosene or solvent. After this, roofing material is rolled out on the prepared concrete base, the sheets 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). This material is usually laid in two layers. Care must be taken to ensure that top sheets covered the joints of the lower panels.
The foundation structure is being reinforced, which will increase its strength and load-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 this, the remaining solution is poured out.

After the concrete has hardened, the developer can continue construction work. In order to protect the building as much as possible from the harmful effects of harmful environments, he must carry out internal insulation of the foundation. To do this, you should use sheets of extruded polystyrene foam, which are glued to the floor and walls of the premises and are subsequently finished.

To ensure that any building does not require repairs for a long time, you need to take care of creating the most reliable foundation possible. This applies not only to the construction of the foundation, but also to its further insulation.

Thermal insulation is especially necessary in cold regions (where temperatures drop well below zero for long periods of time). First of all, this applies to concrete foundations: strip and slab.

Is it necessary to insulate, and why?

P Before considering methods of work and choosing which technology is better, you need to understand why thermal insulation of the base is needed, and whether it is needed at all.The technologies discussed below are equally relevant for those who learn how to insulate a foundation wooden house, and for buildings made of concrete, brick, blocks.

Insulating the foundation solves several problems at once:

Protects concrete from direct contact with moisture. It destroys the structure itself, and in addition leads to dampness in the basement (if there is one).

Protects the base from soil heaving.

Prevents freezing of a monolithic slab (or strip foundation).

The soil surrounding the foundation contains a certain amount of moisture. It will differ in different regions and in different areas, but there is always water in the ground. And upon contact with concrete, it will accelerate its destruction. The moisture contained in the pores of concrete freezes, turning into ice. Ice occupies more volume than water, i.e. it expands. Over time, this leads to the appearance and enlargement of cracks.

Another problem that foundation insulation solves is soil heaving. It occurs with seasonal changes in weather: in minus temperature the soil rises, after which (with warming) it sinks back.

This negatively affects the condition of the monolithic slab, since constant pressure occurs on the concrete. This poses a particular danger if the work technology was violated when pouring the foundation (which often happens). In this case, insulating the foundation allows you to create a kind of protective layer that will take on the pressure of the soil.

The most serious reason why it is necessary to insulate the foundation from the outside is its freezing in winter. In cold weather, the soil freezes, taking heat away from the stove. As a result, the floors in the rooms on the first floor become cold, and the basement (if there is one in a private house) becomes cold and damp.

For the reasons mentioned above, we can firmly say whether it is necessary to insulate the foundation, and why. For permanent buildings that must last more than 10 years, thermal insulation is clearly necessary.

Basic requirements for materials

U Warming the foundation cannot be done with any material.The main criteria are :

durability: thermal insulation work requires digging a trench around the entire perimeter of a private house, and doing this every few years is difficult and expensive);

water resistance: even with a protective structure (which covers the insulation from the ground), moisture may penetrate the heat insulator, which will impair its effectiveness.

List of methods and general stages of work

U warm the foundation of the house from the outsidepossible in several ways :

Board materials (foam plastic, polystyrene foam, mineral wool boards).

Bulk materials (expanded clay).

The work can be carried out both at the stage of construction of a private house, and for already finished construction . The second option is better than the first: after construction, the foundation must sit for some time (about six months or a year, ideally, if we are talking about a two- or three-story building) residential cottage) to finally get into shape. However, during construction very often deadlines are running out, and therefore minimum holding periods are observed, after which work on the construction of walls begins immediately.

Regardless of exactly how the foundation will be insulated, there are general rules and stages:

Ideally, the entire perimeter should be coated with a primer. This is cheap, takes little time, and at the same time allows you to create additional protection for the concrete from moisture.

Work (regardless of what technology is used) is easiest to carry out in the warm season. The weather these days should be dry, since you will have to work in a trench, and the wet ground will significantly complicate the task.

Application of board materials

The most common option is the use of slab materials. These include:

Insulating the foundation with polystyrene foam (or mineral wool) is the most popular option among those who want to cope with the task themselves. The work can be carried out in two ways:

Self-tapping screws. The insulation sheet is attached to the surface of the slab. About 6-10 screws are used per 1 m².

For glue. The plates are glued to the surface using a special solution.

The general operating rules are as follows:

The insulation begins to be attached from any lower corner, horizontally (i.e., the next sheet is attached to the side, and not from the top).

Each subsequent row is mounted with a shift: so that the seams between the insulation do not create a continuous line).

The seams are taped with waterproofing tape (or construction tape).

Insulation of the base with polystyrene foam (video)

Application of Spray Insulation

TO This option includes the use of polyurethane foam. The technology has a significant drawback: insulating the foundation with your own hands is difficult to do: spraying requires special, expensive equipment. Its purchase is unprofitable if you plan to insulate only 1 cottage, even with all the additional outbuildings.

To get acquainted, let's look at how to insulate the foundation of a house from the outside in this way:

The insulation itself is prepared at the work site (produced by mixing two components T ov in an airtight container).

From a special installation, polyurethane foam is sprayed onto the surface, where it instantly hardens, turning into dense foam.

Of the obvious advantages of this method:

saving time (in 1 work shift, 1-2 workers can cover more than one hundred “squares”, while attaching foam plastic can take more than 1 day);

does not require surface leveling;

creates a continuous layer (without seams, like between sheets of foam);

polyurethane foam is the “warmest” insulator (thermal conductivity is about 0.03 W/mK).

Insulation of the base with polyurethane foam (video)

Application of bulk materials

U The easiest way to warm the foundation with your own hands is to use a bulk insulator - expanded clay.

A wider trench will be required for such work. Expanded clay, as insulation, does not hold back the cold well, and therefore a layer of 5-10 cm (as with the materials above) will no longer be enough. The recommended width of the expanded clay layer is 40-80 cm.

Let's consider how to insulate correctly foundation in this way:

The bottom of the trench dug around the perimeter is covered with a waterproofing film (or geotextiles, orYou can use regular dense polyethylene, ideally in several layers).

Approximately 10-20 cm of crushed stone is poured onto the bottom.

Placed in crushed stone drainage pipe (to remove moisture that may enter the expanded clay layer.

The trench is backfilled with expanded clay.

Ideally, it is recommended to make a partition from brick, plastic or metal panels or slate,and pour expanded clay between the partition and the foundation. In this case, it will act as a barrier, preventing moisture from getting inside (on the expanded clay).

Installation of insulation protection

After the insulator is fixed to the surface, it is recommended to complete the insulation of the foundation with your own hands by installing a protective structure. Regarding expanded clay, it was already mentioned above.

For polyurethane foam or sheet materials, work is performed as follows:

Mounted wooden or metal carcass- lathing. It is attached to the foundation, and the insulation is installed (sprayed) between the frame.

A protective layer is attached to the frame using self-tapping screws. This can be slate, plastic or metal (if metal, it must be galvanized or stainless) panels or sheets.

As an option, you can build a brick partition in front of the insulation (as mentioned above).

An uninsulated foundation can result in greater heat loss than a tightly sealed, well-insulated home.

Foundation insulation reduces the need for high power heating system and avoids moisture condensation, which often occurs as a result of temperature differences between inside base and soil around the base.

A poorly designed foundation insulation system can cause many problems, such as moisture problems and pest infestations.

Insulation of basement external walls

Installing insulation on the outside of the strip foundation base has several options. External insulation has the following advantages and disadvantages:

Advantages:

Minimize thermal coupling and reduce heat loss through the foundation.
Protection against moisture penetration into interior finishing.
The insulation protects the foundation from the effects of the freeze-thaw cycle in extreme climatic conditions.
Reduced condensation.
Reduces wastage of internal space.

Flaws:

Expensive installation for an existing building if also installed drainage system along the perimeter.
Many external insulating materials susceptible to attack by insect pests.
Many contractors are not familiar with the proper procedures in detail.

Experienced builders believe that the best way to insulate a foundation is to insulate it from the outside. Carefully designed perimeter drainage system consisting of washed gravel, perforated plastic pipe and fabric filter. Highly recommended for areas with poor soil drainage.

Some foam insulation is made with boric acid to discourage termite infestation. However, borate can slowly leach from most materials when exposed to groundwater.

Insulation of basement internal walls

In most cases, the best way is to insulate the internal walls of a strip foundation; this is also a less expensive option for a finished building. This insulation has the following advantages and disadvantages:

Advantages:

This is much cheaper than insulating external walls for existing buildings.
There is a wider choice of materials as you can use almost any type of insulation.
There is no threat of insect infestation.
A space insulated from the cold ground is more effective than using external insulation methods.

Flaws:

Many insulations require a fire resistant coating because they release toxic gases when ignited.
Reduces useful internal space by 3-5 cm.
Does not protect against moisture penetration like external insulation.
If the perimeter has poor drainage, the insulation can cause moisture to become saturated around the perimeter of the foundation and seep through the foundation walls.

New methods of foundation insulation

Some new building systems make it possible to build a ready-made insulated foundation without the use of wooden or metal formwork, is a system of concrete forms (ICF), simply put, permanent formwork made of polystyrene foam, which uses rigid foam as forms for formwork, thereby insulating the inside and outside of the foundation.

Thermal panels

Among the new products, there is also insulation that does not require finishing, This thermal panels made of polystyrene foam with stone chips.

Polyurethane foam

Other synthetic polymer material, used for thermal insulation of foundations, is polyurethane foam. It is prepared by mixing liquid components using a special technique. Manufacturing process carried out at the construction site.

Apply this material by spraying method. Cured material for 17-20sec.

One of the main advantages is the extremely low thermal conductivity of 0.028 W/m0S. In addition, the spraying method contributes to the formation of a solid layer of insulation where there are no seams (even if the foundation has complex geometry). Thus, it completely eliminates the possibility of cold bridges appearing. The spraying process itself takes much less time than installing the panels.

The disadvantage of polyurethane foam is the cost, including installation, which is more expensive than extruded polystyrene.

The strength of this material depends on its density. For basic insulation, it is recommended to use polyurethane with a density of at least 60 kg/m3.

Blocks with insulation inserts

There are also blocks with foam inserts. They are installed as blocks that do not require plaster. Some concrete block manufacturers add materials such as polystyrene or wood shavings into the concrete mixture.

Despite the fact that filling the cavity of the blocks with insulation improves their thermal properties, at the same time it does not significantly reduce heat loss compared to insulation made on the surface of the walls, or on the outer or inner parts of the foundation walls.

Research and computer models showed that an infill block provides little heat savings because most of the heat passes through the solid parts of the walls, such as the block material and mortar.

Insulation of slab foundations

Slab foundations are often insulated along the outer edge of the slab support or between the screed and the slab. The base of the slab is often isolated from the ground. Each approach has its own advantages and disadvantages.

Insulating the outer part of the foundation or the edge of the slab reduces heat loss from both the foundation and the slab.

This method provides greater protection for the foundation from freezing. This also allows for a shallow foundation without the risk of damage from soil heaving. All exposed parts of the insulation should be covered with metal, cement or another type of membrane to protect it from damage.

When insulating a slab foundation, the insulation should be located between the support and the slab. This protects the insulation from insects and damage better than external application and insulates the slab from the cold base.

Insulating an existing slab is generally not practical.

However, you can insulate the outside of the slab from top to bottom:

Blind area.
3-8 cm of sand.
2-5 cm of rigid insulation.
A layer of polyethylene 150 microns as a moisture retarder.
10 cm of washed gravel and drainage pipes under the slab.

The insulation can be applied over the existing slab, from top to bottom, as follows:

Finish floor covering.
RIP insulation
Substrate
Rigid polystyrene foam glued with moisture-resistant strips along the joints.
Polyethylene layer 150 microns.

An alternative is a floating floor, which consists of:

Finish floor covering.
RIP insulation
2 layers of 12.5 mm thick OSB or plywood should be screwed, overlapping all the seams of the previous slab by 30-60 cm, there should be a 12.5 mm gap in the seams between the slabs to compensate for thermal expansion. The same gap must be made from the edge of the wall.
Rigid polystyrene foam glued with moisture-resistant strips along the joints.

The above methods have the following advantages and disadvantages:

Advantages:

Relatively simple installation.
The floor is insulated from the ground.
The floor surface is close to the air temperature in the room.

Flaws:

Expanded polystyrene requires fire-resistant coatings.
This can increase the depth of frost penetration along the edge of the slab in extreme climates.
In summer, the floor will not receive coolness from the ground.

Insulation of the basement floor from the inside

Insulating a basement depends on whether it has ventilation. Traditionally, basements are ventilated to avoid moisture problems. However, this method does not always work well.

If the basement must be ventilated, carefully seal all openings in the ceiling to prevent air from entering the house. Insulate the ceiling by pressing fiberglass insulation tightly to the base.

Cover the insulated surface of the floor with a vapor barrier. Carefully seal all seams to prevent air and moisture from passing through. Secure the insulation with mechanical fasteners so that it does not fall out between the joists. The insulation is attached between the beams.

Place a sheet of polyethylene, or other equivalent material, over the earthen floor. Carefully seal all seams with tape. Cover the plastic sheeting with a layer of sand or concrete to protect it from damage. Do not fill the film with anything that could make holes in it, such as crushed gravel.

If the basement is not ventilated, then all of the above is done + insulation of the walls and floor.

Insulation of the foundation slab. Features of insulation of a monolithic foundation slab? Internal insulation technology

Scope and types

Construction technology of insulated slab

Preparing the base

Concrete preparation

Waterproofing

Insulation

Reinforcement

Pouring the foundation slab with concrete

Curing

When to remove formwork

Differences between an insulated monolithic Swedish slab and a video about its construction

Insulation of foundations

Foundation insulation material: penoplex

How to insulate: from the inside or the outside?

Penoplex insulation at the construction stage

Swedish foundation

Advantages of an insulated foundation

Insulation of the foundation slab: work order

general information

Advantages of a slab foundation

Advantages of slab insulation

Disadvantages of a slab foundation

Insulation materials

Installation of insulated slab

Site preparation

Insulation of the slab

Rules for installing heating pipes

Insulation under the foundation slab: step-by-step instructions

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 provide?

What insulation should I use for the foundation?

Polyurethane foam

Extruded polystyrene foam

Extruded polystyrene foam with grooves

Foundation insulation with polystyrene foam

Insulation of the foundation with polyurethane foam

Insulation of a monolithic foundation slab with polystyrene foam

Choice of insulation

External insulation technology

Internal insulation technology

Insulation of the foundation slab body

Insulation of slab foundations - Technologies, subtleties, nuances

Insulation methods

Advantages of timely insulation

What materials can be used to insulate a slab foundation?

Rules for insulating slab foundation structures

Carrying out insulation measures during the construction process

Is it necessary to insulate, and why?

Basic requirements for materials

List of methods and general stages of work

Application of board materials

Insulation of the base with polystyrene foam (video)

Application of Spray Insulation

Insulation of the base with polyurethane foam (video)

Application of bulk materials

Installation of insulation protection

Insulation of basement external walls

Insulation of basement internal walls

New methods of foundation insulation

Thermal panels

Polyurethane foam

Blocks with insulation inserts

Insulation of slab foundations

Insulation of the basement floor from the inside

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