Water pipes

Why is it impossible to insulate the house from the inside? Do I need to insulate aerated concrete - options with and without insulation Do I need to insulate the foundation.

The first and most famous reason why you should take a responsible approach to the issue of warming the base of the house is constant fluctuations in temperature and soil moisture. Natural phenomena provoke cracks in the foundation and its subsequent destruction.

It may also seem important for the economical owner the fact of energy saving: a warm foundation will reduce heat leakage and save heating costs by a third.

Besides, insulated foundation is able to protect:

residential premises from the penetration of low temperatures;
communications from cold and moisture.

To insulate the foundation means to protect it not only from the cold, but also from the water.

Excessive moisture can cause a lot of trouble to the foundation of the house and the house itself, if the barrier is not taken care of in time.

Even on the basis of these few examples, one can give a positive answer to the question: is it necessary to insulate the foundation?

Warming and

The foundation is insulated from the outside before the floor is laid and the walls are erected. And you can do the inside when there is no way to carry out the outside, and if there is a basement in the house.

Both the first and second options are designed to:

prevent the penetration of cold into the base structure and into the living quarters;
prevent the infiltration of rain and melt water.

Separately internal insulation contributes:

the formation of its own microclimate in the basement, which also affects the microclimate throughout the house;
the formation of a reliable barrier to groundwater;
preventing the accumulation of condensate on the basement ceiling and the formation of mold.

However, choosing a method one point to be taken into account: the difference between external and internal insulation is that the first method reliably prevents seasonal temperature changes from affecting the foundation, and the second one gives a weak spot at this point.

Insulating the foundation from the inside, you need to be prepared for the fact that temperature fluctuations during the change of seasons can be fatal for the foundation and structure.

How to insulate different types of foundation?

During the laying of the foundation of the house, there should not even be a question, but is it necessary to insulate the foundation?

If you build “for centuries”, then, undoubtedly, the life of the building you have planned will, first of all, depend on the strength of the foundation. And also - warmth and comfort in the house.

Consider, how to insulate various types of foundation to protect the base from negative natural influences.

shallow foundation

It is used in the construction of light frame buildings, has two types: tape and tile.

The insulation is placed at a distance of 1-1.5 meters from the foundation masonry, and between them they form a zone of non-freezing soil.

Column Foundation

To insulate this type of foundation, it is necessary to equip the so-called. pick-up - a kind of basement, the main function of which is protection from moisture and freezing of the space between the soil and the foundation.

The pickup process is laborious, but during the operation of the building it will justify itself.

It is done like this:

It is necessary to dig a shallow (200-400 mm) trench.
Fill a third of the trench with sand or gravel.
Attach bars with grooves (slots, slots) to the foundation pillars.
Insert special thin boards into the grooves.
Fill the lower part of the structure with expanded clay and your foundation will be out of danger.

Monolithic foundation

An excellent basis for compact buildings without a high base, a very popular type of foundation among domestic developers.

Monolithic foundation insulation technology the most expensive, as it is made using polyurethane foam. But, despite the high cost of such a heater, it is used with the prospect that the costs will pay off in the future.

The cost of heating a house when using this type of insulation is scanty.

Pile-vit foundation

Buildings on such a foundation have one characteristic feature: an open space between the foundation and the ground, which always leads to significant heat losses. Warming of the pile-vit foundation is mandatory, otherwise it will be very uncomfortable to live in the house.

Stages of insulation:

Waterproofing grillage.
Installation of a heat-insulating layer.
Finishing work on the outer layer of thermal insulation.

As a heat-insulating material in the process of warming such a foundation, as a rule, foam is used.

Foundation insulation scheme

For owners of private houses used for year-round living, the question remains: Is it worth insulating the foundation from the inside if it is already insulated from the outside?

For a greater heat-saving effect, it is possible to carry out double-sided insulation of the base of the house. So, usually, economical owners act, taking care of the heat in living rooms and not wanting to overpay for heat supply.

Foundation insulation scheme heated room combines two types of insulation: horizontal and external vertical.

How to insulate

As a heater you can use traditional materials. The same as for wall and ceiling insulation:

mineral wool, ecowool;
Styrofoam;
polyurethane foam;
expanded clay;
Earth.

Petr Kravets

Reading time: 3 minutes

A A

The construction of any building is always carried out according to the recommendations of SNiP and TSN, all work is done in strict compliance with the rules and instructions of GOST. But on the question of whether it is necessary to insulate the foundation of a house without a basement, there is no clear regulation.

Here one must be guided by common sense, because even if the building is not equipped with a basement, the base of the reinforced concrete structure is a powerful cold bridge, which will lead to significant heating costs and significant work to strengthen it against frost swelling.

Thermal insulation of the basement is carried out without fail, both horizontally and vertically.

When designing and building a strip foundation, especially a shallow one, the norms of SNiP 50-101 are used.

With this version of the foundation, the house is not equipped with an underground, but such a project can be implemented if the following work is done: ring-type drainage is made around the perimeter, the soil under the base is replaced with non-metallic one, and all cracks are backfilled with a sand-gravel mixture.

Such procedures can only partially solve the problem, preventing the soil from filling with moisture. To do this, in building codes, it is separately recommended to insulate the blind area of the house with polystyrene foam, laid horizontally with a width of 0.6-1.2 meters, to a depth of about 0.4 m.

At the same time, access to the side surfaces of the strip foundation with a slight depth should be maintained.

Most often, at the stage of digging a foundation pit, its walls are pasted over with extruded polystyrene foam of increased density. This solves several problems:

Cold bridges are eliminated, which ensures floor insulation in the house and significantly reduces heat loss;
Provides protection for waterproofing, which can be damaged by swelling from frost;
The freezing of the concrete base is reduced, especially in cases of damage to the waterproofing layer, when the concrete absorbs moisture from the ground. When frozen, it increases by 9% in the pores of the material, which leads to gaps and cracks in the base of the house.

Insulation work on the foundation can increase its resource during operation by 40%, regardless of the presence of a basement in the house.

The house in which people permanently live is heated, in which case floor insulation is made in several versions, each of which has its own advantages.

Floor on the ground over a layer of thermal insulation

Sheets of extruded polystyrene foam reduce heat loss, the ground under the house can freeze through the basement and foundation, which in themselves will be cold bridges;

Floor on the ground without thermal insulation

In this case, heat loss through the ceiling will be maximum, but the ground under the house does not freeze due to the heat transferred from the house.

Overlapping on beams

Between the finishing and rough layer of floors in a private house, thermal insulation is arranged in any case according to building rules, and ventilation products must be made in the basement. In this case, the soil and the foundation will definitely freeze through with constant frost, standing for several days.

Floor slab

The coldest option when heat loss is maximum. All structures and surfaces below the floor slabs will be cold.

Summing up, we can confidently say that if there are defects or gaps in the external waterproofing, then all concrete structures that are used underground absorb moisture. It freezes and creates cracks and tears inside the material.

If backfilling is done with soil that was removed from the pit during digging, then swelling of parts of the foundation becomes frequent. This is fraught with deformation and destruction of floor screeds. All these problems can be eliminated by high-quality thermal insulation.

Vertical thermal insulation consists in gluing surfaces outside with expanded polystyrene, which gives insulation to the basement and facade of the house. Horizontal - insulates the blind area by 10 cm with polystyrene foam 1.25 meters wide with a depth of 0.5 meters.

These types of protection against heat loss should be carried out comprehensively, since soil around the entire perimeter is adjacent to the insulated foundation (base of the house).

Thermal insulation of a house without heating

If the house is not heated, which is often found in garden cooperatives, then there is often an opinion that the protection of the foundation and soil is not needed due to the lack of people living in the house. This is a big mistake, since the design loses more than half of its resource in its reliability and useful life.

Do I need to insulate the basement if there is no basement? The need for thermal insulation of the building becomes clear if we study the thermal contours of the structure:

Geothermal heat is present in every section of the structure;
Horizontal insulation keeps the soil warm, preventing it from freezing;
Vertical thermal insulation protects the structure and the waterproofing layer from freezing during the cold season.

The horizontal contour of polystyrene foam must be made in one piece, without joints and seams, therefore there are some features of laying material plates:

Under the sole of the foundation around the entire perimeter of the pit and in part of the blind area, a heat-insulating layer is made, which will keep the heat under the whole house;
Comprehensive protection against heat loss is done under the ground floor, the edges of the foundation from the inside, the outer sides of the foundation and under the material of the blind area to insulate the entire house and create a continuous line of the thermal contour.

If you do not make thermal insulation with polystyrene foam of the outer surfaces of the strip foundation, then its destruction can occur even with high-quality waterproofing, equipped drainage systems and when replacing the soil in the sinuses with special materials.

At first glance, the foundations do not need to be insulated, since they are located below the ground level. Hence the question: Do I need to insulate the foundation of the house? And if it is necessary, then why and in what cases?

You can immediately assume the following answer: in the absence of a basement, it is not necessary to insulate the foundation, but it is enough to insulate the outer walls of the house and the floor (floor) of the first floor, and the foundation itself should be insulated only if there is a basement. But not everything is so simple, as you can read below.

Explanation just in case. Perhaps someone does not know: the foundation is what is below the ground level; socle - a continuation of the foundation above ground level, to the bottom of the wall. "In the common people" usually the base is also called the foundation, but we will call them correctly, although the technologies and materials for warming both are the same.

Why insulate the foundation of the house?

If you look at a picture of a house taken with a thermal imager, you can see places where heat is actively leaving the house:

The brightest places are those through which heat loss occurs most intensively. The photo shows that there are such places in the area of \u200b\u200bthe foundation / basement. It was found that heat loss through the foundation is approximately 17% of the total heat loss of the building, i.e., almost a fifth, which is quite robust. Here is the answer to the question "why insulate the foundation?": to spend less on heating.

So, the basement and foundation are insulated to prevent heat leakage in the lower (basement) part of the house. Such heat losses are fraught with the formation of dampness on the walls of the basement and the appearance and development of mold on them. But even if the house does not have a basement, the insulation of the foundation will keep our warmth where it is needed most: inside the house.

The foundation is insulated both outside and inside (from the basement side). I must say right away: it is preferable to insulate the foundation from the outside than from the inside, and why - read on.

How to insulate the foundation of the house?

The foundation is insulated with heaters produced in the form of plates and, of course, not afraid of moisture. As a rule, these are the following materials:

extruded polystyrene foam,
perlite bitumen boards,
foamed synthetic rubber.

In addition to those listed, it is possible to insulate the foundation and plinth with polyurethane foam, which is applied by spraying:

The foundation is insulated by backfilling with materials such as expanded clay, boiler slag, etc. Backfilling with such materials not only insulates, but also prevents the foundation from being squeezed out by heaving of the soil.

Explanation just in case. What is backfill? A trench is dug for the foundation. Formwork is installed in the trench - two walls of, for example, boards. Concrete is then poured between these walls, getting the actual foundation. But the width of the trench is wider than the foundation. This gap then needs to be filled up, which is called backfilling.

Of the plate heaters for self-insulation, extruded polystyrene foam is best suited (read more about the insulation technology for them). Well, backfilling with expanded clay or slag is also not a problem to do yourself, even easier.

The dangers of a perfectly insulated foundation

Here are those times. We just talked about the benefits of warming, but it turns out that there are also some dangers? For the budget, right? Unfortunately no. For home!

To understand what we are talking about, you need to remember that there is such a phenomenon as heaving of the soil due to the expansion of moisture in the soil when it freezes. The problem of heaving is not a joke, because of this the house “dances”: it rises in the cold, it gets warmer - it falls. Moreover, the freezing of the soil is uneven even in the same area:

It turns out that in one place the heaving force is greater, in another it is less, which is why the house does not just “dance”, but “dances” like a drunk. It's bad for the house.

If the foundation is not insulated, then the heat from the room heats the ground under the house - all the thermal energy goes into the ground in a powerful stream (red area under the foundation):

Such soil does not freeze, the heaving of the soil moves away from the building. On the one hand, this is good. On the other hand, why do we need to heat the ground? No need. Well, they insulated the foundation to some extent:

The key phrase here is "to some extent". Because there are different insulation standards: at least Russian and Western. According to Russian standards, 50 mm of extruded polystyrene foam is enough to insulate the foundation. As a result, we see what is shown in the diagram above: thermal energy is retained in the room, the ground under the house warms up less, but still warms up, which is why the freezing zone (white) is still away from the house. Good: we save some money on heating and frost heaving is not scary.

The humor is that in the West, where the climate is considered milder, the norms for insulation are more stringent: not our 50 mm, but 200 ... 300 mm of insulation under the foundation! That is, in the West they strive to insulate ideally, reaching zero heat loss. Well, since all their brain tricks reach Russia sooner or later, we will continue - we will insulate the foundation ideally, according to the Western model ... so far in theory. We get the following - the soil freezing zone creeps under our house, which makes frost heaving dangerous for it:

Conclusion: the greater the thickness of the thermal insulation, the less heat leakage, but there is a danger that the soil under the foundation will freeze.

And if so, then it makes sense to talk about ...

How to protect the foundation of the house from frost heaving of the soil?

Although this applies to the topic of home insulation indirectly.

The forces of frost heaving act in two ways: 1) from below on the sole of the foundation; 2) tangentially along the sides of the foundation.

Under a foundation with a "normal" depth - below the freezing level of the soil - moisture will not freeze; if the sides of the foundation were also made honestly, smooth, then the forces of frost heaving, directed along the tangents, are not terrible. Here is the first answer for you: make the foundation in good faith and using time-tested technologies.

Unfortunately, this is not always possible, as a rule, for reasons that depend not on us, but on the terrain and soil quality. Then you have to arrange shallow foundations: tape or slab. And with them it’s a different story: with perfect insulation, the freezing zone moves towards the edges of the foundation and, in order to move it away, they make an insulated blind area along the perimeter of the building:

This is especially true of facilities whose construction is planned to be "frozen" for some reason - either until spring, or until better times.

If we screw this thing up - we don’t do anything against frost heaving, then we can get something like this:

In addition to warming the blind area, there are other ways to get rid of frosty heaving of the soil. Let's consider them all.

How to prevent frost heaving of the soil?

I know five ways.

2. The device of a closed loop drainage system around the perimeter of the building:

The drainage system is a perforated plastic pipe sprinkled with rubble, laid along the perimeter of the building at the base of the foundation. So all the moisture that is in the soil under the foundation will be removed from under the foundation - go into the drainage system. It can even be just a rubble channel, without a pipe.

Where to lay the drainage pipe, you ask a question?

Under the foundation itself:

IT IS FORBIDDEN! The pipe will burst from the pressure from above, and there will be no drainage.

We lay the drainage pipe outside the foundation so that there is no pressure on it:

The pipe, of course, will be in the cold zone. It will freeze, and the drainage will not work. In order for the drainage pipe to continue to work, an insulated blind area is again arranged:

3. Replacement of heaving soil with non-heaving soil:

The meaning of this is the following. In terms of composition, soils come in different consistencies: some are very heaving (which absorb more moisture into themselves), some are not heaving at all (crushed stone, rocky soil ... that is, fractions through which water cannot rise due to capillary processes and cannot , respectively, will be stored there). The replacement is that the loam or clay is replaced with sand. Sand not only has a greater bearing capacity, but the sand fractions are also quite large, water practically does not linger in it, and the filtering capacity of sand is much higher than that of clay soil. The sand for the pillow should be as large as possible available in our region, it should not contain sandy loam, loamy impurities (lumps of clay are acceptable, they are typical for quarry sand, we just throw them away at the time of the pillow). The absence of clay will allow high-quality compaction of the sand.

In addition to sand, crushed stone, sand-gravel mixture (SGM), screenings can be used. But the use of crushed stone and screenings is justified if they are comparable in price to the price of sand. Well, or if you really want to. And also if the soil has a low bearing capacity, and then they try to increase its bearing capacity with the help of a crushed stone pillow.

It is on this that the device of a sand or sand-gravel cushion under the foundations is based.

Note. For the installation of a pillow under the foundation, you can use a concrete battle, but it is better not to use a brick one, because there are different bricks, including clay. And in general, the bricks crumble from moisture.

4. Laying the foundation below the freezing level.

5. If we arrange a columnar foundation, then make it T-shaped - with an extension at the bottom:

How it works, in my opinion, is obvious: frosty heaving tries to push the column up, but the “skirt” at the bottom does not allow this. The same applies to the tape T-shaped foundation:

You can use one or all methods at the same time, at will and possibilities. But it is better and more correct to carry out anti-rocking measures in a comprehensive manner, because one thing may not be effective, for example, sand has silted up. Or the drain is clogged. With time.

So, I suppose, the theory is enough for now, you can now consider whether it is necessary to insulate the foundation of the house. Your his. In the next article, we will deal with the insulation of the foundation from the outside - we will consider different insulation technologies for different types of foundations.

Do I need to insulate the foundation of the house?

Material with a porous structure.

When creating blocks, use:

Aerated concrete blocks are very convenient: they can be cut (and quite easily), they weigh little, do not affect people's health, cost relatively little and have a high level of sound insulation.

But aerated concrete also has a number disadvantages:

They are not sufficiently resistant to mechanical stress. That is, from such material it is possible to build buildings with a maximum height of 3 floors.
The material is relatively fragile and therefore requires precise installation of the foundation and laying of the blocks themselves. Errors in laying (or installing the foundation) often lead to cracking of the material.
Anchors should also be used as fasteners (other fasteners can lead to concrete cracking).
Since the material is porous, it will absorb moisture well, so you need to clad or cover with a special solution.

Do I need to insulate a house made of aerated concrete 400

Now this topic is relevant among the owners of aerated concrete houses "to insulate or not to insulate their homes."

It is difficult to answer, it depends on many parameters, including the location of your house (region).

Although often the construction team insists on insulation (mandatory) to increase the cost of work.

If you want to avoid unnecessary expenses, you need to calculate how much this insulation will pay off, if it pays off in more than 100 years, then the meaning of such insulation ...

If the walls are built with high quality and your climate is mild enough, then you will probably have enough simple roof insulation (also inspect windows and doors, insulate if possible), but without external wall insulation.

So is it necessary to insulate aerated concrete?

It is necessary to insulate if your house is located in a cold climate and this will bring you benefits - that is, savings on heating.

But keep in mind one thing, aerated concrete blocks have a high level of vapor permeability and they need to be insulated in such a way that the vapor permeability decreases from the outer part of the wall to the inner one.

Insulate aerated concrete house with your own hands

Typically, blocks are insulated from the outside using one of 2 types of insulation:

Penoplex;
Mineral wool.

External insulation of blocks with foam

Penoplex insulation is the most profitable option (in terms of cost) and in terms of quality of insulation. Foam insulation is best done from the outside.

First of all, you need to prepare the surface. Since the blocks themselves are even and with a smooth surface, it is not necessary to further level the surface to the ideal.
If there are cracks or chips, they must be covered with plaster (or special glue)
You also need to close the window slopes.
After plastering, the surface is coated with a primer (this creates greater adhesion).
After the primer has dried, you can start laying foam boards.
The insulation is glued to the surface with cement glue and additionally pressed with dowels.
And in conclusion, you need to take care of the decoration of the facade.

External insulation of blocks with stone wool

Warming of the house can also be done with stone wool, it can be used both under siding and under plaster.

If under the siding, then they install the crate using vertical guides on the outside of the house, lay the insulation in niches and cover it with a layer of vapor barrier, and fix the siding on top.

Is it possible to insulate from the inside?

Experts and craftsmen recommend insulating it from the outside, it’s not worth it inside. Since from the outside to the inside, the vapor permeability should decrease. Otherwise, moisture will accumulate in the blocks themselves, and the strength of the entire structure will decrease.

Only external insulation will help you to insulate the house and protect the structure from moisture.

The average cost for warming a house made of aerated concrete

Option 1

Many of the regular readers of our insulation portal often ask the question: Do I need to insulate the foundation of a residential building without a basement? If the structure has a basement, then there are no questions - we isolate it in any case. We all understand that the absence of a basement means that the building stands on a concrete foundation, which is recessed into the ground to a certain depth. To find out the details, we turned for help to the leading engineer, an expert in the field of control and accounting of heat consumption - Leonid Zverev.

— Hello, Leonid! Please clarify the situation, is it worth insulating the foundation of a house without a basement? To what extent will the dwelling lose heat through the concrete base, at what stage should this be done, what insulating materials should be used for this? Our readers are very interested the effectiveness of the choice of such insulation and, of course, the level of heat conservation when insulating the basement.

Leonid Zverev:

- Good afternoon. Well, for starters, let's figure out why the basement is missing? Modern building systems of modular or frame houses do not initially provide for a basement. From the side of heat engineering, such a room, significantly deepened into the ground, is not required in the current living conditions.

All communications are brought into a specially designated room or annex, the so-called control unit, where a boiler, water filters or a reserve tank are installed.

We return to the main question: there is a house, it stands on a foundation, why insulate it? In this case the concrete base is in contact with the walls which are insulated and maintain a comfortable indoor temperature. Concrete absorbs moisture in large quantities. This does not harm the material itself, it does not collapse from this and retains its original strength. However internally, the amount of heat from the walls and floor begins to be transferred to the base, so to speak, trying to heat it up. As a result, we get the problem: through the junction of the floor and walls to the concrete base, a significant amount of heat begins to leave, so carefully accumulated indoors in various ways.

The most effective type of insulation is extruded polystyrene 5-15 cm thick. installed outside the foundation. Such plates are quite simple and quick to install, do not require special skills or professional tools. The joints between the plates, as well as the irregularities of the foundation base, are filled with liquid foam in the required amount.

If the housing construction is located on a flat area and there may be cases of accumulation of moisture under the base of the building, it is also necessary to take care of waterproofing. The hydrobarrier can be of several types: in the form of a rolled film coating, water-based cement materials, roofing felt or resin applied directly to the insulated surface.

Currently, the building materials market has a huge selection heat-insulating liquid coatings, the so-called ceramic-based paints. Such materials simultaneously act as a heat insulator and prevent the penetration of moisture into the basement.

In conclusion, I will say the following - the insulated foundation is not afraid of freezing during frosts, the flooring will retain heat more efficiently, and the bottom of the wall will never get moldy.