Insulation of the foundation Insulation of the foundation of the house Insulation of the floor. Insulation of the basement of the foundation from the outside: we make insulation with foam plastic with our own hands with step-by-step instructions. Sheet foamed plastics

The strip foundation is not just the basis of the structure, the support of its structure, but can perform quite utilitarian functions, being the walls of inhabited basements, basements or semi-basements. In order for such premises to be warm and cozy, the foundation should not be a simple concrete casting, but a structure that will provide reliable thermal insulation of the interior. To do this, not only horizontal, but vertical surfaces of the strip concrete foundation are subject to insulation.

Concrete itself, despite its high strength and high resistance to stress, is a rather poor heat insulator. It easily receives heat and also gives it away easily. A bare concrete wall will not be a good barrier between the cold of the winter soil and the heat of the living quarters.

Note that the degree of cooling of the foundation is also affected by the depth of its occurrence. If the strip foundation is not buried in the ground below the freezing level of the soil, then areas of freezing soil may form under the house, which will adversely affect the climate in your home.

How can you insulate the foundation?

There are two main ways to insulate foundations. They differ depending on the period in which the work is performed. One option is to insulate the foundation even at the stage of its pouring, and the second is the subsequent insulation, which is carried out after the concrete casting has matured.

The most preferable is the insulation of the foundation at the construction stage. This integrated approach allows you to get good results. In order to achieve reliable thermal insulation of the foundation, even in the conditions of central Russia with severe winter periods, the warming process must be carried out from two sides.

The most logical approach to insulating the foundation during construction is fixed formwork.

Insulation of the foundation with fixed formwork

Fixed formwork is a spatial structure, inside which a concrete solution is poured. At the stage of mortar solidification, it acts as an ordinary wooden formwork, that is, it limits the spreading of the concrete mortar. However, unlike wooden formwork, after the concrete has matured, the fixed formwork is not removed, but remains on the thickness of the concrete as a layer of insulation.

Fixed formwork can be made from various materials. Particularly popular is the construction of fixed formwork from polystyrene foam boards. These are plates made of foamed polymer material, which have many tiny air bubbles in their composition.

At first glance, the disadvantage of such formwork is its high cost. The cost of its purchase and installation is several times higher than the cost of classic wooden formwork. However, such a foundation will not need to be subsequently insulated, so the total costs will be quite comparable.

Insulation of the foundation after pouring it

Work on the insulation of the poured foundation is best started directly in the process of its maturation. If you are inattentive to this stage of building a house and return to it later, then you will not be able to carry out insulation work with high quality.

The classic ways to insulate the foundation after its construction is to fall asleep on the basement floor of a layer of expanded clay, which is subsequently poured with a leveling screed. Expanded clay is clay baked in special ovens and its mass is an excellent heat insulator. Also, to increase the level of thermal insulation between the ground, the basement and the living rooms, thermal insulation of the floor of the first floor of the house is carried out.

We warm the foundation with the help of the earth

This option of foundation insulation is extremely economical on the one hand, but very labor-intensive and voluminous on the other hand.

The essence of this insulation is very simple - all the walls of the foundation to the level of the first floor are covered with earth. Thus, it turns out that under a layer of earth, inside a kind of mound, all the basements are found. Earth or sand in themselves are good heat insulators, but in order for this insulation to be effective enough even for central Russia, the foundation will have to be sprinkled with a very solid volume of sand. So, to backfill a foundation with a rather modest size of 10 by 10 meters, you will have to spend about one hundred cubic meters of sand.

A significant advantage of this approach will be the exclusion of the impact on the foundation of heaving soils of your site. In some cases, backfilling the outer wall of the foundation with sand is recommended not even for the purpose of thermal insulation, but in order to exclude the impact of soil movements on the foundation.

When backfilling the foundation with soil or sand, it is necessary to provide channels for air ducts that will provide ventilation for the basement. Naturally, work on this method of insulation must be started immediately after the dismantling of the wooden formwork, even before the walls of your future home are erected.

We insulate the foundation with a layer of expanded clay

As already mentioned, this is also one of the classic ways to insulate the foundation. In principle, expanded clay insulation can be combined with earth insulation.

In addition to the usual backfill, expanded clay can also be used as a filler for concrete castings. Expanded clay is small lumps of clay fired in a specially rotating kiln. Inside each lump there are many air cavities, which determines the excellent thermal insulation properties of this material. Thus, expanded clay can be used as a filler in a concrete solution instead of gravel.

So, expanded clay filler can be used in the construction of low-depth strip foundations. At the same time, expanded clay can be added not only to the concrete mortar for the foundation walls, but also when the floor is screed, thereby providing a completely closed heat-insulating contour of the basement.

We insulate the foundation with polystyrene foam

The development of chemical production has led to the widespread use of synthetic insulation materials. One of these materials is expanded polystyrene, which is a plate. There are many air bubbles inside.

Expanded polystyrene sheets can be glued to both concrete casting and brick walls. When installing such slabs on a foundation consisting of concrete blocks, that is, having places where individual parts are joined, they must be positioned so that the slab joints are not above the concrete block joints. This will prevent the formation of "cold bridges".

Expanded polystyrene boards can be glued from the lowest level of the foundation to the roof itself - on the entire outer surface of the wall.

Insulation of the foundation with mastics

A certain insulation of the foundation can also be achieved during the work on their waterproofing. So, to prevent the penetration of moisture from the soil, it is recommended to cover the vertical walls of the foundation with a layer of bituminous mastic. In addition to protection against moisture, several layers of such mastic will help you isolate cracks and the smallest holes, joints of foundation slabs through which heat can leak from the room.

In contact with

Owners of private houses, in an effort to make the house warm, sometimes pay attention only to walls and ceilings. At the same time, they forget that the insulation of the foundation is an equally important point.

As a result, there are problems of cold floors and excessive heating costs. Once you have invested in the insulation of the supporting base, you can save an impressive amount on heating bills.

What caused the need for thermal insulation?

A significant part of the cool air enters the room through the foundation. Therefore, the designs of many buildings are built in such a way as to raise the floors above the ground. Warm, heated air rushes up. When the roof is not insulated, heat seeps out. And the room is filled with cold air, which penetrates through the floors of the building. Therefore, the need for thermal insulation of the supporting base is obvious. If the walls are in frozen ground, the room will have to be constantly heated.

When it comes to maintaining heat in an old house, it should be remembered that all components of the system must retain heat: the foundation, walls, ceilings and roof. If at least one thing will release heat, then the whole building will not be able to keep it at a high level.

High-quality insulation of the foundation can reduce the impact of groundwater and cold on the base of both wooden and stone buildings.

Isolation methods

All methods for warming are usually divided into two types. The first - before pouring the foundation, the second - the insulation of the finished building. The first option is preferable and it is he who is used more often. In severe winter conditions, the concrete foundation is insulated on both sides.

Concrete is known for the almost complete lack of thermal insulation, it cools easily and heats up just as easily. During construction, they use both a heater, which is mounted directly into the formwork, and a special fixed formwork. Such panels are many times more expensive than simple ones, but the amount of costs is lower than the price of dismantling a simple formwork and subsequent insulation.

Insulation of the foundation of an already operated house is a complex and responsible undertaking. In cases where the building was built with insufficient foundation depth, freezing of the soil under it will be very strong. In such situations, for thermal insulation, the foundation is dug both inside and outside, and later a heater is laid. At the same time, to prevent freezing of the floor in the basement of the old building, it is sprinkled with expanded clay.

For many years, the most commonly used methods of foundation insulation have remained unchanged: with the help of earth, expanded clay or expanded polystyrene.

Earth insulation

This option is the most economical, despite the impressive volumes of sand that will have to be unloaded and leveled. The method lies in the fact that the earth is filled up to the level of the future floor, as a result, the entire basement and foundation are underground.

Ground insulation is carried out before the construction of the house. Be sure to provide a ventilation shaft for the basement.

Advantages of the method:

insulating with soil, you do not have to buy a heater;
the house will not freeze through the basement.

Flaws:

large volumes of earth and sand will have to be leveled;
soil - a weak heat insulator;
the walls of the foundation will let the cold into the room, albeit in smaller quantities.

Thermal insulation with expanded clay

One of the cheapest and most effective methods. Sometimes builders combine insulation with soil and expanded clay.

In the process of pouring the foundation, expanded clay is placed in the inner part of the prefabricated formwork. This method is used for both wall and floor insulation, in both cases it is quite effective. The unique properties of expanded clay are contained in its porous structure, due to which it does not allow moisture and cold to pass through, retains heat well. The only losses occur due to the fact that the cavities between the granules are filled with cement, and it is a conductor for cold.

Expanded clay insulation is often used for strip foundations. With a low-depth foundation, the material is used to insulate the floor in order to completely get rid of the freezing of the earth in the basement.
If the insulation occurs after pouring, then the formwork is usually used the lightest, since expanded clay is practically weightless. Sometimes slate sheets are used as formwork.

Expanded clay is a fragile insulation. When used for floor insulation, mineral wool and a film are laid on expanded clay to protect against moisture.

What about styrofoam?

When deciding how to properly insulate the foundation, often the choice falls on the foam insulation method. This is a versatile and affordable material.

Styrofoam is sold in sheets that are easy to install. Therefore, its use allows you to do all the work with your own hands.

Waterproofing

Before fixing the sheets of insulation, it is important to waterproof the surface. There are many waterproofing methods:

applying several layers of bituminous mastic;
waterproofing with roofing material;
surface plastering;
applying special penetrating compounds.

Slab laying

After providing waterproofing, expanded polystyrene sheets are mounted on the surface to be insulated. Sheets are laid from the bottom of the foundation to the level of the future floor. The insulation is fixed with the help of special adhesive compositions, which are applied pointwise to its surface. It is necessary to lay sheets of expanded polystyrene close to each other in order to obtain a monolithic surface. The seams between the insulation boards are sealed with mounting foam.

Expanded polystyrene eventually collapses under the influence of sunlight, so it should be securely covered from above with facing panels.

Thermal insulation around the perimeter

Before you insulate the foundation around the perimeter, you need to remove the soil along the entire base of the building to a depth of about half a meter and a width of about one and a half meters. After creating the trench, the sand is backfilled by about 20 cm, it is carefully compacted.

Styrofoam plates are installed on the "sand cushion". For additional reliability, insulation materials are attached using special adhesives, for example, bituminous mastic. The joints formed between the plates are blown with mounting foam. You can also fill the gaps with cold-applied bituminous mastic.

After fixing the insulation and completing the other related work, sand is again covered with a layer of at least 3 m.

The corner zones of buildings lose more heat than flat surfaces. Therefore, in these places you should use a larger (one and a half times) layer of polystyrene foam.

The advantages of perimeter insulation with polystyrene foam are as follows:

the design of the insulated foundation is protected from the appearance of deformations and cracks;
at the same time the basement is also thermally insulated;
polystyrene foam has good performance properties, which makes it a fairly durable material.

Also, expanded polystyrene can be used for internal insulation of an old house if it is impossible to carry out external insulation. To do this, the walls are glued from the inside with foam boards. A room insulated in this way can become a full-fledged room.

The use of penoplex

Penoplex material is more perfect than polystyrene. Insulation of the foundation with foam plastic prevents its deformation, the building will last longer.

Penoplex has a structure with closed pores, so that it is not subject to the destructive action of water. Other important advantages of the material are its strength and low thermal conductivity.

How is the installation carried out?

Penoplex can be installed only a week after the implementation of waterproofing, the methods of which were described above.

Penoplex is produced in the form of plates with grooves of a certain configuration. These grooves provide a very tight fit of the plates to each other without gaps.

Fastening is carried out with special adhesive compositions. You need to choose only those compounds that are not capable of destroying the insulation. The glue is applied pointwise, gradually processing small surface areas. The slab is applied to the foundation and pressed for 40 seconds. After gluing the slab, proceed to the next section. The process is continued until the entire surface of the base of the building is insulated.

It is necessary to glue the plates so that they protrude 35–50 cm upwards. After the installation is completed, the resulting voids are covered with non-porous materials. At the end, thermal insulation of the soil along the perimeter is carried out.

High-strength sealed board with PU foam

Polyurethane foam or PPU is a modern building material with many advantages. It is characterized by low thermal conductivity, strength, durability and environmental friendliness. It is easy to work with polyurethane foam - no additional fasteners are required for installation, its application to the surface is quick. PPU has high waterproofing properties that prevent moisture from entering, thereby protecting the building.

The main advantage of using polyurethane foam as a heater is the inability to spoil the result - the final coating is always obtained without cracks, bumps and joints.

How to work with polyurethane foam?

The foundation is insulated with polyurethane foam by spraying the insulation onto the surface using special installations. The resulting foam is firmly connected to the base of the structure, filling all cavities. It turns out a high-strength plate, very hard and tight. Since the material has a closed structure and there is no air gap, condensation cannot appear in such a product.

Thermal insulation of the foundation with polyurethane foam is the most effective method. It is suitable for both new buildings and for thermal protection of an old house. But the cost of such insulation is high and it is impossible to carry out the work on your own, since special equipment is required.

There are many options for waterproofing and warming the foundation, it remains only to choose which one is most suitable.

In this article I will tell you about how to insulate the foundation of various types. This will allow you to independently make your home more economical and comfortable.

Do I need to insulate the foundation

Often, beginners ask on the forums what is the best thing to do, insulate - the foundation or the floor? In fact, the question is incorrect, since both operations are aimed at solving different problems.

So floor insulation prevents the penetration of cold into the room through the ceiling.

The thermal insulation of the foundation performs the following functions:

protects the base from moisture, as well as multiple freeze / thaw cycles, and other negative factors. Thus, the insulated foundation is more durable;
prevents cooling of the ceiling and walls as a result of contact with the frozen foundation, respectively, reduces the overall heat loss of the house;
protects the basement from low temperatures, if any. This allows you to store vegetables and other products in it.

Therefore, if you decide to insulate the house, it is highly desirable to insulate the foundation as well.

External insulation of the strip foundation

First of all, consider how to insulate the strip foundation, which is the most common.

There are two ways to insulate such a base:

thermal insulation outside it is this method that allows you to protect the base from freezing and other negative factors;
insulation from the inside - as a rule, it is performed in cases where there is a basement or basement under the house. This procedure allows you to make the room warmer and, accordingly, reduce heating costs.

Often, internal insulation is performed together with the external one. Next, consider both options for thermal insulation.

So, the insulation of the strip foundation from the outside can be divided into five stages:

Preparation of materials

First of all, you need to decide on the choice of thermal insulation material. Usually, expanded polystyrene or extruded polystyrene foam is used for these purposes.

this material has a much higher strength than polystyrene - 0.2-0.5 MPa versus 0.07 MPa for polystyrene;
not afraid of moisture;
durability is much higher than that of polystyrene;
has low thermal conductivity - 0.027-0.034 W / mK versus 0.037-0.043 W / mK for foam.

The density of extruded polystyrene foam for external thermal insulation must be at least 33 kg / m 3 so that it has sufficient strength. On sale you can find a special insulation for the foundation, for example, Penoplex Foundation.

The only drawback of expanded polystyrene is the high price, which averages 4500 rubles per 1m2.

In addition to thermal insulation, you will need the following materials:

liquid waterproofing, for example, bituminous mastic;
geotextiles for arranging drainage;

drainage;
glue-foam for penoplex;
rolled waterproofing, for example, roofing material;
materials for pouring the screed (needed to equip the blind area).

Excavation work

External insulation of the foundation of a private house begins with excavation, unless, of course, you are engaged in this procedure at the construction stage.

Earthworks are carried out as follows:

First of all, you need to dig out the strip foundation. To do this, dig a trench to the entire depth of the foundation, about one and a half meters wide. Thereafter the foundation should be left for a while so that it dries well;

Next, you need to perform drainage. It is especially necessary if groundwater is located close to you or if rainfall is abundant in your area.
To arrange drainage around the perimeter of the house, you need to dig trenches at a distance of half a meter from the foundation. The depth of the trench should be such that the drainage pipe is located at the level of the base of the foundation.;

fill the bottom of the trench with sand and gravel. The thickness of the layers should be about ten centimeters;
then the bottom of the trench should be covered with geotextile with a twist to the edges;
after that, drainage pipes are laid in the ditch. In this case, it is necessary to withstand a slope of at least 2 cm per meter. The drainage system should be connected to a storm sewer or diverted to a storm well;
then fill the trench with crushed stone and wrap the pipes with the edges of the geotextile.

It is necessary to start excavation work in dry, warm work. Therefore, it is best to deal with the insulation of the foundation in late spring or summer.

The earthworks have been completed so far.

Foundation preparation

Now it is necessary to prepare the surface of the foundation for further insulation.

The work is performed in the following sequence:

the dried foundation must be cleaned of soil residues and other dirt. In this case, it is necessary to remove the chipping sections of concrete. To clean the surface, you can use a metal brush;
protruding areas that will interfere with the installation of insulation must be removed. Try to keep the surface as even as possible, as the durability of the foundation depends on it;

to improve the adhesion of the mastic, the foundation must be treated with a bituminous primer using a roller or brush;
after the surface has dried, the foundation is waterproofed. To do this, apply bituminous mastic on its surface with a roller or brush. I recommend using a ready-to-use mastic that does not need the addition of a solvent or heating.

All recesses, cracks, etc. must be filled with mastic in order to form a continuous coating with a thickness of about 2-4 mm.

Now you need to wait for the mastic to dry, and you can start warming the foundation of the house.

Insulation installation

The installation instructions for the penoplex look like this:

apply glue to the back of the insulation. Glue should be located around the perimeter of the plate, as well as in the center;
then the plate must be applied to the surface of the foundation and lightly pressed down. Start pasting the foundation from the corner.

Try to place the tiles as close to each other as possible. Some types of extruded polystyrene foam have chamfers, due to which they are connected into a lock;

as a rule, it is impossible to ideally paste over the foundation with insulation boards. Therefore, you need to inspect the walls and fill the existing gaps with adhesive foam.

This completes the heating process. I do not recommend additionally fixing the insulation to the foundation with dowels, since it will already be securely fixed with soil. In addition, when installing dowels, you will have to make holes in the foundation that will violate its integrity.

The arrangement of the blind area

Now you need to make an insulated blind area by doing the following:

the pit along the perimeter of the house must be covered with earth so that a trench remains about 30 cm deep from the ground level;
then fill the trench with sand about ten centimeters thick and carefully tamp;

on top of the trench, roofing material should be laid close to the walls of the house. Joints of roofing material, which should overlap each other, glue with bituminous mastic;

then foam is laid on the waterproofing;
a screed is poured over the foam plastic according to the standard scheme.

This completes the insulation of the foundation from the outside.

Thermal insulation of the strip foundation from the inside

Warming the foundation with your own hands from the inside can also be divided into several stages:

It is possible to insulate the basement only after its thorough waterproofing, since the room must be dry.

Preparation of materials

To insulate the foundation from the inside, you will need the following materials:

slab insulation - you can use any, including polystyrene or even mineral wool;
glue for insulation;
dowels-umbrellas;
primer;
reinforcing fiberglass mesh.

Wall preparation

Before insulating the foundation of the house from the inside, it is necessary to prepare it:

first of all, the walls must be cleaned of dirt and dust, as well as old peeling finishes, if any. To do this, they can be brushed and then wiped with a damp cloth;
then the surface of the foundation must be coated with a primer. If the base is concrete, use an adhesive primer. In other cases, you can use a universal primer.

The primer is applied with a brush or roller in a thin layer. After the first layer has dried, the procedure is repeated.

Before insulating the foundation, you need to perform thermal insulation of the floor. This operation is performed in the same way as the thermal insulation of the blind area - waterproofing and insulation are laid, after which the screed is poured.

Insulation installation

After the walls have dried, we begin the installation of insulation:

if a dry mixture is used as glue, it must be diluted in water to a mushy consistency;

the adhesive is then applied to the back of the board with a notched trowel. If the surface of the walls is uneven, you can apply glue in lumps;

then the plate is glued to the wall. At the same time, adjust its position using the level. According to this principle, the entire first row of insulation is pasted over;
the second and all subsequent rows should be staggered so that the seams of the plates do not match. During the installation process, use the level and the rule to make the surface of the walls smooth;

after the glue hardens, you need to drill holes and install the dowels. Each plate must be additionally fixed with five dowels. Slightly recess the caps of the fasteners so that they do not interfere with further finishing.

This completes the installation of the heater.

Reinforcement

Reinforcement of the insulation is carried out as follows:

fiberglass mesh sheets must be cut into strips of the desired length;
then glue the prepared mesh to the insulation. To do this, apply the adhesive to the wall surface with a notched trowel. Then attach to the area treated with glue, and draw a wide spatula over it so that the mesh is immersed in the adhesive solution.

In this way, paste over the entire surface of the walls with a mesh. At the same time, it is important to arrange it so that each subsequent strip overlaps the previous one by 10 cm;

Apply a second coat of adhesive with a wide trowel after the first has dried. The layer thickness should be several millimeters.

This completes the work. Now you can prime the walls and putty them for finishing.

Thermal insulation of the pile type foundation

Now consider how to properly insulate the foundation of a private pile-type house. This work can be divided into 4 stages:

Preparation of materials

To insulate the pile foundation, it is necessary to prepare the following materials:

insulation - the best option is extruded polystyrene foam;
materials for the frame - bars and boards, you can also make a frame from metal profiles;
antiseptic impregnation;

slab isolon;
expanded clay
material for covering the foundation, for example, basement siding.

Frame installation and insulation

When insulating a pile foundation, a big problem is heaving of the soil. If you place the skin close to the ground, then as a result of heaving it will be broken.

As a rule, this problem can be solved by the gap between the skin and the blind area. But it leads to a significant decrease in the effectiveness of thermal insulation. Therefore, I recommend performing insulation according to the technology I invented.

Work begins with the arrangement of the skin, which is performed as follows:

around the perimeter of the house you need to dig a trench, which will be located above the skin. The depth of the trench should be 20 cm;
then the trench must be filled with expanded clay. Due to this, when the soil is heaving, the skin will not break. On top, you can lay a layer of sheet isolon (foamed polyethylene) with a thickness of at least 50 cm, which will serve not only as a heater, but also as a damper;

Now you can assemble the frame. To do this, bars or boards need to be fixed on piles around the perimeter of the house. To fix them, strips with holes for bolts are welded to the piles, you can also use clamps, and do without welding;
to increase the strength of the frame, horizontal rails should be connected with vertical posts;
all wooden parts of the structure must be treated with an antiseptic. If the foundation of a wooden house is being insulated, also treat the wooden grillage and the lower crown of the structure with a protective compound;

after that, the penoplex should be fixed on the frame. To do this, you can use ordinary nails and rivers, to which the panels will subsequently be attached;
fill the gaps between the foam boards with foam;
near the lower edge of the structure along the perimeter of the house, you need to install a starting profile for attaching panels. Make sure the punk is vertical;

install corner profiles at all corners using self-tapping screws. Make sure the corners are vertical.

The arrangement of the blind area

The blind area is performed as follows:

dig a trench around the perimeter of the house about 40 centimeters deep and 1-1.5 meters wide;
cover the bottom of the trench with a layer of sand and gravel 10 cm thick. Each layer must be carefully compacted;
then cover the surface of the trench with waterproofing;

along the outer edge of the future blind area, make drainage according to the scheme described above;
then extruded polystyrene foam is laid on top of the insulation, and a screed is poured on top according to the standard scheme.

Try to make the screed as close to the foundation as possible, so that after sheathing it, a gap of about 5-7 mm is obtained between the blind area and the foundation.

The blind area should have a slight slope from the house so that water does not accumulate at the base.

Frame sheathing

The foundation is done like this:

the panels are brought into the starting bar with the lower part, with which they are connected into a hook. The extreme panels from the corner are inserted into the corner profiles. From above, the panels are attached to the crate with self-tapping screws, as shown in the diagram above.
Thus, the entire frame is sheathed;

an ebb is mounted above the casing, which allows water to be diverted to the blind area. The ebb must be of such a width that it covers the gap between the base and the blind area;
at the end of the work, the gap between the blind area and the foundation sheathing should be filled with isolon. On top, you can apply building sealant. Thanks to this, water will not seep under the foundation.

This completes the process of warming the foundation.

Conclusion

From this article, you learned in detail how to insulate the foundation. I also recommend watching the video in this article. If you have any questions for me on this topic, leave them in the comments, and I will try to answer as soon as possible.

Insulation of the foundation from the inside is used in cases where it is not effective enough or for some reason impossible. It should be borne in mind that internal thermal insulation allows you to increase the temperature inside the basement or basement floor, insulate the floors in the house, but does not protect the foundation itself from damage caused by freezing.

There are several ways to insulate the foundation from the inside, and they are often combined with the interior decoration of the basement. In any case, before starting the installation of thermal insulation, you should take care of effective and high-quality waterproofing of the foundation, and it is better to give preference to those methods of waterproofing that make it possible to make the entire thickness of concrete resistant to getting wet, for example,. A dry foundation is less prone to freezing, and therefore damage.

Types of internal thermal insulation of the foundation

In general, the methods of insulating the foundation from the inside are similar to the external insulation of the foundation. The most commonly used methods are:

Backfilling of the basement with expanded clay. Allows you to reduce the cooling of the floor of the first floor. Insufficiently effective method, suitable for country houses of temporary residence;
Insulation of the basement walls with plates - polystyrene foam, polystyrene or foam plastic, with their subsequent finishing. A very popular method of thermal insulation, most often used in combination with external thermal insulation of the foundation for buildings with basements used.
Insulation of the foundation from the inside with polyurethane foam. A very effective way of additional or independent thermal insulation of the foundation, which allows you to create a seamless coating with excellent adhesion, but this work requires the involvement of professionals with a special installation.

The choice of method of warming the foundation from the inside

When choosing a method, you need to focus on several factors:

The design of the building, the dimensions of the basement or semi-basement;
The presence of external insulation and temperature conditions from the outside of the foundation;
Soil type and location of groundwater;
The required temperature regime in the basement after insulation, the presence of heating and ventilation;
The need for further decorative finishing.

A cheap method of internal thermal insulation of the foundation is filling the space under the floor with expanded clay. This material removes water and creates an air cushion that protects the floors of the first floor from cooling. You can fill up both the entire space under the floor and the formwork installed on the inside at some distance from the foundation walls.

If the basement is used to accommodate domestic premises, and its walls need not only insulation, but also finishing, it is advisable to use polystyrene or foam boards, which allow you to create an even coating ready for cladding. The most high-quality and durable in this case will be the insulation of the foundation both from the outside and from the inside - by eliminating the temperature difference, you can avoid the formation of condensate on the inner walls of the basement. If insulation from the outside is not possible, it must be done: concrete treated in this way is not subject to freezing, but retains vapor permeability, reducing moisture under the insulation slabs. It is also necessary to arrange supply and exhaust ventilation, since these materials do not allow moisture to pass through.

If funds allow, you can choose thermal insulation with polyurethane foam - this method is effective and suitable for any basement.

The technology of backfilling the foundation with expanded clay

This technology is usually used in wooden houses, summer cottages and garden houses. Materials for backfill thermal insulation are inexpensive, and its implementation does not require any special skills.

Backfill thermal insulation technology:

Formwork is prepared from boards or plywood panels, installing them at a distance of at least 0.3 meters from the inner walls of the foundation around the entire perimeter. The height of the formwork is up to the floor level of the first floor.
The boards used for formwork are carefully treated with an antiseptic for wood that is used in contact with the ground. Strengthen the formwork with slopes. A plastic film is laid at the bottom of the formwork - it serves as a waterproofing protection against the absorption of moisture from the soil by expanded clay.
The backfill is made with dry expanded clay - pebbles of volcanic origin. The expanded clay layer should be equal to the height of the formwork. In some cases, with a low height of the basement, it is possible to cover the entire space under the floor of the first floor with expanded clay, while waterproofing is laid on the entire backfill area.
You can additionally insulate the floors by laying a layer of vapor barrier membrane and mineral wool mats between the joists.

The technology of insulation of the foundation with polystyrene plates

Polystyrene is the second name for the familiar foam, modified to give it special properties. Polystyrene plates of various brands are presented on the market, they differ in density, resistance to mechanical damage, and thickness. To insulate the foundation from the inside, polystyrene plates 50-100 mm thick are sufficient.

The technology of thermal insulation of the foundation from the inside with polystyrene:

Polyurethane foam insulation of the foundation and basement

A modern, highly effective method applied by the method of spraying foaming liquid under pressure. The result is a layer of foam with a closed structure, resistant to getting wet, without seams and joints. The application of polyurethane foam does not require any special preparation of the walls and can be completed in the shortest possible time. The only serious drawback of this method is its high price and the need to call specialists, which, however, pays off during the operation of the building due to the excellent heat and waterproofing properties of the polyurethane foam coating. You can apply any finishing materials on it and use it for internal and external insulation not only of the foundation, but also of any other house structures.

Insulating the foundation of the house from the outside is no less important than the walls and roof, because the non-insulated base of the building passes ≈ 20% of thermal energy to the street. And these are extra expenses for heating and energy carriers. Non-insulated walls are more susceptible to the destructive power of rains, winds, frosts and the sun - moisture, turning into ice, breaks concrete, and microcracks cause the appearance of "cold bridges", accelerating the transfer of heat from the house to the outside. Ultraviolet and wind only help the destruction of concrete or brick.

The benefits of insulation

Microcracks will not always remain small, they will increase over time, thereby increasing the risk of failure. Total insulation of the foundation from the outside is the displacement of the dew point from the wall material into the insulator, which helps to maintain the technical and physical characteristics of concrete. For example, when the ground freezes by 15%, the rupture of water molecules can cause the soil to shift by 30-35 cm, which can deform it. In hard rock, these risks are reduced, but do not disappear, so the depth of the foundation of the house is calculated based on the freezing point of the soil in the region. The material is fixed vertically and horizontally, and it is desirable to do this in 2-3 layers.

Insulation of the house outside is carried out not only for heated rooms. Even in the absence of a basement, the insulation of a shallow strip foundation, together with the plinth, reduces heat losses by 15-25%.

For those who like to save money: with proper insulation of the foundation and basement, the floor of the lower floor can not be insulated.

A cold foundation creates conditions for easy penetration of air from the street into the house. Therefore, the floor level is immediately brought to 20-30 cm above the ground. If it is not insulated, the rooms in the basement and the walls of the basement will be constantly damp and cold. The benefits of insulation are manifested in the following:

The overall heat losses are reduced, energy costs during the heating season are reduced.
The heaving soil under the house does not deform the foundation when thawing or freezing.
Prevents condensation and fungal diseases from appearing on the walls of the basement.
The service life of concrete structures is increased.
An additional advantage is the protection of the waterproofing layer from damage.
The displacement of "cold bridges" closer to the outer surface.

The issue of insulation is solved in the same way: before pouring it around the perimeter of the trench, a fixed formwork is equipped, and it is advisable to use expanded polystyrene for it, which will be an additional warming layer. Then the foundation after pouring will be in a "bag" of expanded polystyrene and will be insulated from the outside and from the inside.

How to properly insulate

Beginning - digging a trench along pre-marked lines, indicated by a cord tied to pegs around the perimeter of the foundation. With a large amount of work, it is easier to rent an excavator, and it is better to trim the walls of the trench with a shovel.
A sand-gravel cushion ≈20 cm thick is laid on the bottom and rammed with moisture.
A vertical fixed formwork made of expanded polystyrene boards is attached to the outer and inner walls of the trench. Slab gaps are filled with construction mounting foam - this will help to avoid wetting the foundation with groundwater.
A reinforcing frame is created. For the base, reinforcing bars of 10-16 mm are used, which are knitted together with soft steel wire or fastened with special plastic clamps. Reinforcement neutralizes the action of compression and bending forces from the ground and the weight of the building.

When arranging wooden formwork, it is possible not only to insulate the outer walls, but also to lay (or apply) a layer of waterproofing. You can mount it immediately if a block foundation was built, and only after four weeks when pouring concrete. When using liquid waterproofing (bitumen, tar, mastic), the room must have a positive temperature. Rolled materials are fixed with dowels or on the same mastic.

The question of how to insulate the foundation from the outside is solved by using extruded polystyrene foam (foam foam). It has high specifications. Moreover, the depth of insulation does not depend on the thickness of the foam layer, since the plates can be built up on top of each other (in a checkerboard pattern). The thickness of the thermal insulation layer should increase, approaching the soil surface. For central Russia, up to 1-1.5 m from the ground, foam boards up to 8 cm thick are laid, then 3 cm can be used. On the north side, 10 cm plates are attached to a depth of 1-1.5 m, below - 5 cm.

Advantages of penoplex:

High rates of heat and sound insulation, strength and moisture resistance.
Neutral material, thanks to which rodents, fungal organisms and insects do not damage it.

Styrofoam is fixed in several ways:

heating method. To do this, with the help of a building hair dryer, the waterproofing agent is heated until it begins to melt and, until it has cooled down, a foam polystyrene plate is pressed against the wall.
If the walls are uneven, then the plates are fixed to the mastic or building cement-polymer adhesive. The mastic is applied pointwise with a brush; after gluing, the fastening can not be duplicated with dowels-umbrellas.
In both the first and second versions, the joints are filled with mounting foam.

The last step is backfilling the trench. The soil is mixed with sand in proportions of 1: 1, the gap between the foundation and the foundation pit is covered with this mixture, every 20-30 cm the sand is watered and rammed. A blind area is made on top.
backfilling

Insulation of the foundation of a wooden house

The basement is a monolithic continuation of the base, located above the ground surface, so it also needs to be insulated and protected from moisture. According to the rules, the draft level of the floor on the first floor should be on the same level as the top of the basement. Therefore, the insulation of the latter will not allow the walls to freeze, while at the same time making the floors of the first floor and the basement ceiling warm. Small additional costs are offset by savings on heating.

A house made of logs or timber may have a wooden plinth, and foam plastic is not suitable for its insulation, since polystyrene foam does not allow air to pass through. This is important for long-term operation, because such a house suffers from condensation in the basement.

Such a base is recommended to be insulated with polyurethane foam. This is a new synthetic insulation, it is applied by spraying, and the PPU expands and fills all the pores, cracks and joints between the materials. Its good adhesion helps the foam adhere to any surface.

Algorithm for warming a wooden basement:

First, a wooden crate is constructed - after applying PPU, it is sheathed with a decorative finishing material, for example, siding or clapboard. Between the laths, the crate is filled with polyurethane foam using a sprayer, which, expanding during hardening, forms a continuous durable layer up to 7 cm thick. And this is enough - the thermal conductivity of the material is 0.019-0.035 W / (m · TO).
The hardened excess foam is cut off with a knife or a carpentry cutter, after which the surface is covered with decorative building materials.

This method is much easier, but only suitable for wooden bases. The general principles of insulating a house from any building materials are clear and simple so that it can be done independently without using the paid services of specialists.

Categories

Popular