Insulation of concrete floors with polystyrene foam. The simplest and most affordable material for floor insulation is polystyrene foam. Calculation of insulation thickness

I didn’t want to answer due to lack of professionalism and little experience, but since there are, as correctly noted, many options, then I will also speak out. And I’ll start with the fact that it is indisputable that thermodynamics and molecular kinetic theory of gases (MKT)
So, heat is transferred from a warmer body to a less warm one. Everything that exists in the world is matter, and it is transmitted through it. Heat transfer, that is, direct contact, convection, that is, the transfer of energy with particles of liquid and gas in space and radiation (the only way to transfer energy in a vacuum). I repeat - the first transmission options are only through MATTER, and the third does not work if there is interference to the beam (for example, a shadow on a sunny day). So here it is. Energy is generated (transformed) in a residential building and then, passing through a number of obstacles (enclosing and supporting structures), it escapes into the atmosphere and lithosphere. Our task is, since losses cannot be avoided, to organize the loss of energy in such a way that the floor is warm. So, we can have three design options - an insulated floor, the same plus a heap, and, finally, point 2 plus a blind area with insulation (or insulation of the foundation to the freezing depth).
If we insulate only the floor, which is good, then what we get is warm above, but very cold below. You can make a very good floor pie and get good thermal insulation, but it is very difficult to get energy to be transferred in a house from top to bottom - convection works from bottom to top, the contact area with the walls is too small for heat transfer, and radiation from heating devices is small - the temperature difference is small, plus the batteries are full . But there is cold air below, which constantly takes energy! Fans, etc. are unnatural and therefore wrong. Correcting design flaws mechanically (electric floors, etc.) is a dead end. This time. Secondly, even an excellent floor WORKS - the floor is the most loaded part of the house and its characteristics change the fastest, that is, during operation we may be faced with the fact that part of the house will have to be repaired earlier than the house as a whole, and moreover, the most inconvenient for part of the simultaneous residence in it is the floors. Zapadlo does not sleep...
Option 2. There is a blockage. That is, we transfer part of the heat filter to the border of the warm circuit. Everything is the same, BUT! The underground temperature rises, the air temperature rises. We reduce the thermal insulation of the floor and increase the thermal insulation of the pile, and the temperature in the underground also increases, and the temperature of the floor surface increases accordingly. Now about something else. Here they don’t want to drown the earth, but! One way or another, when maintaining a non-freezing regime in the house, the ground is not frozen, since, in the absence of debris and, accordingly, the greater temperature difference between the subfloor and the “above floor”, energy exchange increases proportionally, in our opinion, heat loss. Only in this case, the “comfort point” is clearly not located on the floor surface, but much higher. The warmer the subfloor, the lower this “comfort point” is and the easier it is to finally lower it to the floor. And to help this, you need to connect another source of heat exchange - convection, that is, either through the air intake of the furnace, or through holes in the floor, we connect the living space with the subfloor, then the temperature on the floor surface rises and reaches the required level. This is where it’s time to connect the MKT. The tree absorbs moisture at high RELATIVE humidity, trying to reach equilibrium, and the fungus develops when the wood is certainly saturated with it. By creating convection, we normalize humidity and antisepticize the floor structure in the most natural way. Here, at least there will be puddles under the floor - there is ventilation - there is no fungus. Well, about the birds. It is much easier to inspect and repair rubble than floors. At this point I didn’t write about the features of radiation at different temperature differences, because I had pretty much forgotten this matter, anyone who is interested will find it.
Option 3. An insulated blind area is added, and even with snow on top. Everything is quite simple here. The earth turns from a heat cooler into a heat accumulator, allowing you to save the same energy.
Somehow I described everything concisely and one-sidedly, but my fingers hurt.

Properly carried out floor insulation work is the key to maintaining a comfortable temperature in the house and minimal heat loss. Such work can be carried out both during the construction of a new building and in existing houses, for example, insulating the floor in a wooden house from below from the basement. Not only high-quality floor insulation, but also the correct choice of heat-insulating material will help achieve energy savings and reduce heat losses by up to 20%.

The presence of a basement in the house allows you to insulate the floor below Source oig-homes.com

Advantages of bottom insulation

From the point of view of labor costs, it is more profitable to insulate the floor from above. In this case, the insulating layer is mounted between the frame (joists) and the top finishing layer.

But in some situations, bottom insulation is preferable.

This method of thermal insulation is most often used in private houses with an uninsulated basement, garage, and in frame buildings on pile and pile-screw foundations.

Bottom insulation has a number of advantages:

the insulation layer is not subject to loads from furniture standing on the floor and people moving around the house, so you can use thermal insulation material of any hardness;

the height of the room does not decrease;

Not only the top flooring, but also the entire floor frame is protected from freezing, which reduces the likelihood of freezing and water getting on the wood - this increases the service life of wooden structures and ensures their reliability.

It is more expedient to insulate a house on stilts from below Source valet.ru

Thermal insulation materials

The choice of insulation for a wooden house is based on two criteria: non-flammability and the ability to resist the formation of mold fungi and other microorganisms. But when choosing a material for lower insulation, the specific situation and the intended installation method are taken into account.

Before purchasing materials, it is better to consult with a contractor than to insulate the floor in a private house from below. Most often used:

mineral wool;

Styrofoam;

penoplex;

• expanded clay

Minvata It is considered one of the best insulation materials, so many people prefer it. A plus is good sound insulation performance. Cotton wool is not subject to biological destruction and does not burn.

Cons: low mechanical strength and deterioration of thermal insulation properties when exposed to water or steam. Therefore, when using, special attention should be paid to vapor and waterproofing. Cotton wool can be presented in flexible rolls or dense slabs.

Mineral wool in slabs is often used for insulation on the basement side Source silastroy.com

On our website you can find contacts of construction companies that offer house insulation services. You can communicate directly with representatives by visiting the “Low-Rise Country” exhibition of houses.

Styrofoam- another popular insulation material. Combines the good qualities of mineral wool and mechanical strength. But in case of possible fire it releases toxic substances. Thanks to its structure, it retains heat well and ensures minimal heat loss. Long service life eliminates the need for replacement, but the ability to absorb moisture may negatively affect some characteristics.

Penoplex. A recently appeared material is based on polystyrene, into which gas is introduced. The mass is foamed and squeezed into molding containers. The gas evaporates and the output is a sheet of insulation with many pores. This is a material with unique thermal insulation characteristics, very light, and easy to install. Durability and immunity to biological organisms ensure a long service life. The material is not flammable, does not emit harmful substances and does not absorb water.

Penofol- a material for the production of which foamed polyethylene is used. An aluminum film is applied to its top layer, which reflects heat, giving the room the characteristics of a thermos. The structure of penofol does not contain pores, which prevents it from allowing air to pass through.

Penofol perfectly reflects heat Source ultra-term.ru

Expanded clay- bulk material in the form of porous balls, which is formed during the firing of clay or shale. This is a completely environmentally friendly material that has high heat savings, good fire resistance and resistance to freezing. But over time, expanded clay cakes under the influence of gravity and begins to lose quality, so this material must be changed periodically.

To decide how to insulate the floor in a wooden house from below, you need to choose the insulation that will perform the function of a heat insulator better than others in a particular situation.

Principles of installation work

Regardless of the choice of type of thermal insulation, it is necessary to follow the sequence of work performed for proper insulation. If we consider the structure from bottom to top, it will look like this:

waterproofing layer;

thermal insulation layer;

vapor barrier layer;

design for floor installation;

Compliance with this order of work guarantees the maintenance of normal temperature conditions in the room and protection of the structure from freezing and rotting.

The easiest way to insulate the bottom is through joists. They are beams measuring 5x10 cm or more, on which the floor is subsequently laid.

Scheme of floor insulation by joists Source nehomesdeaf.org

After their installation (the recommended distance between adjacent logs is 1 m), sheets of plywood, chipboards or beams are hemmed from below, on which a layer of waterproofing is laid. This is a measure to combat condensation, which can reduce the performance of the thermal insulation layer. Approximately the same technology is used when insulating the Stanislav Chalet house.

Next, the insulation is installed. Its thickness should not exceed the thickness of the log, but it is better to be a few centimeters smaller. The next stage is laying a vapor barrier, which will prevent moisture from entering the insulation from inside the room. And finally the floorboards are laid.

If it is necessary to insulate the finished floor in a wooden house from below, problems with attaching the insulation may arise, which can be solved in one of the following ways:

Glue mount. Almost any insulation can be glued to the surface of the floor (and ceiling in the basement) using special adhesives.

Fastening with slats. To support the insulation, beams, slats, etc. are nailed to the joists.

Fit to size. Tight joining of the thermal insulation material to the joists using, if necessary, spacer wedges.

When laying insulation end-to-end with joists, it is necessary to strictly maintain the size Source nehomesdeaf.org

In any case, it is necessary to lay a vapor barrier, and after insulation, hem the basement ceiling with boards. This will prevent the insulation and its particles from falling down.

On our website you can find contacts of construction companies that have a full production cycle. You can communicate directly with representatives by visiting the “Low-Rise Country” exhibition of houses.

Technology and features of floor insulation from below in a wooden house

For each type of insulation, there are some features of use.

Mineral wool

The sizes of rolls and slabs are usually multiples of 60 cm, which makes this distance the optimal step between the logs. Mineral wool is cut to size with a cutter and placed in the space between the joists. For a tight fit, the size should be 1–2 cm larger than the distance between the joists. Cotton wool should not be pressed down forcefully as this may affect its characteristics.

The best option would be to lay two layers of insulation. The second layer is laid so that the joint of the bottom layer falls on the center of the top piece. This method of installation will prevent cold air from entering the room.

Video description

You can see the stages of floor insulation with mineral wool along joists in the video:

When working with this insulation, it is necessary to use personal protective equipment - gloves, a respirator and goggles, since small particles can get into the mucous membrane and into the respiratory tract, which will cause irritation.

Penoplex and foam plastic

If foam plastic is used when insulating a wooden floor from below in a private house, you must take into account several rules for working with it:

Foam absorbs water, so waterproofing is required. Many experts do not take this property into account during installation, which leads to a decrease in thermal insulation characteristics.

It is recommended to cut the sheets not exactly to the size of the gap between the joists, but 1–2 cm smaller. This will allow you to fill the gaps between the sheet and the joist with polyurethane foam, which will increase the thermal insulation properties. The joints between the sheets also need to be foamed.

Sheets can be fastened using slats, spacer wedges or special adhesives.

Floor insulation with foam plastic in a wooden house Source sk-amigo.ru

The principle of working with penoplex is no different. But due to the smaller thickness of the material, it can be laid with overlapping sheet joints to avoid the formation of cold islands (similar to mineral wool).

But this method significantly increases material consumption, which means additional financial costs.

We invite you to familiarize yourself with the popular one - from the construction company "Shelf" - presented at the exhibition of houses "Low-Rise Country".

Penofol

Due to its property of not allowing moisture to pass through, penofol does not require additional installation of vapor and waterproofing. But to prevent the water vapor that forms in the room from settling on the insulation layer, an air gap is needed between it and the flooring for air circulation.

Laying is done with the foil side up only. This will allow heat to be reflected, which will increase the temperature in the house. Penofol can be used as waterproofing when laying mineral wool or polystyrene foam. This can increase thermal insulation several times, but this method is quite expensive.

Penofol joints are sealed with adhesive tape Source build.4-u.info

The material is sold in rolls and can be easily cut into pieces of the desired size. Fastening is carried out with a construction stapler on staples or with thin slats that are nailed. To improve the result, it is recommended to lay penofol in several layers.

Conclusion

One of the main problems of wooden houses is cold floors, which interfere with a comfortable life and increase heating costs. Proper insulation will solve this problem. Regardless of the material that is chosen for insulating the finished floor in a wooden house from below, it is necessary to strictly follow the general technology and procedure for insulation, as well as take into account the features of a particular insulation. The cost of installing insulation pays off within one season.

If you decide to insulate the floor with foam plastic on your own, then this review is for you. In it we will look at the simplest workflow technologies that anyone can do. You just need to follow simple recommendations to get results no worse than those of the professionals.

How to organize your workflow

Before you start work, you must decide what type of insulation will be used. This depends on the type of structure and the foundation on which the work will be carried out. Simply read the information below and choose the solution that best suits your situation.

Insulation for screeds and soil foundations

Thermal insulation under the screed can be done in two ways:

• Insulating a concrete floor with polystyrene foam (or working on a poured rough screed);
• Insulation of the soil base.

Let's look at each of them and start with concrete floors. First, let's look at what materials are needed.

Material	Recommendations for selection
Styrofoam	A material with a density of 35 kg per cubic meter should be used. It has high rigidity, and its thermal insulation properties are higher than those of less dense options. As for the thickness, it all depends on the object; for interfloor ceilings, 5 cm is enough; for the floor of the first floor of a private house, it is better to put at least 10 cm
Waterproofing material	A film is used under the screed; it must have a high density so as not to tear under loads. You can also lay waterproofing material on top of foam plastic, in which case you need to purchase twice as much of it
Reinforcing mesh	To strengthen the screed layer, you need to put a special metal mesh made of wire 3 mm or more thick. Cell size doesn't really matter
Screed mortar	You can make it yourself from 1 part cement and 4 parts sand. But you can buy a ready-made composition in bags, which is simply diluted with water, the price of such mixtures is low, but the process is greatly simplified and accelerated

The workflow in this case looks like this:

• The surface is cleaned of dirt and debris. If there are irregularities on the slabs or rough screed, they must be knocked down with a hammer or hammer. Slots and cracks are sealed with cement mortar;
• . Most often, a special film is used under the screed; it is black and has a high density, which provides reliable protection of surfaces. When laying, make overlaps at the joints of at least 100 mm and glue the joints with tape; the film should extend 15-20 cm onto the walls;

Lay a special tape along the walls, which will provide a deformation gap; it is sold in hardware stores.

• Insulation with polystyrene foam is very simple: the sheets are laid tightly on the surface. Where necessary, the material is cut into pieces of the required size. The more accurately you cut the elements, the fewer gaps there will be on the surface;

• A reinforcing mesh is laid on top of the foam.. Some additionally lay a layer of waterproofing, but this is not necessary. The mesh is placed so that the sheets overlap at the joints by at least 5 cm, this will ensure the reliability of the floor over its entire area;

• Beacons are exhibited. You can use either products specially designed for this purpose or a profile for plasterboard or wood. The position of the guides is fixed using a solution. Work continues after the mixture has dried and gained strength (usually this takes about a day);

• The solution is prepared and poured onto the floor section by section. The process is very simple: the mixture is distributed over the surface, after which it is leveled using a rule or a level lath. Excess is removed where necessary, the solution is added, and leveling is done again. After carrying out the work, you can walk on the floor within a day, and you need to apply the topcoat no earlier than 1-2 weeks, when the surface is completely dry;

• The last step is to lay the flooring.. If you have leveled the floor well, then no additional preparation will be needed.

Now let's figure out how to insulate the floor with foam plastic on the ground. To help you better understand the workflow, a diagram is provided below.

• Sand for making a pillow (layer thickness can be from 20 to 50 cm);
• Waterproofing material;
• Polystyrene foam with a density of 35 kg per cubic meter or more;
• Reinforcing mesh;
• Screed solution.

The work instructions look like this:

• First of all, the soil base is leveled and compacted.. It’s better to do this in advance so that the earth settles and you don’t have to wait a couple of weeks;
• A sand cushion is poured. Its thickness depends on the level to which the floor should rise. The layer is compacted using a manual or electric tamper. The better you compact the floor, the better;

To ensure that the sand is better leveled and compacted, moisten the surface generously before starting work.

• Waterproofing material is laid. Most often, the surface is covered with plastic film, the joints are made with an overlap of 100 mm and glued, and the edges extend onto the walls by 15-20 cm;

• Foam is laid on the film. Thermal insulation material is placed as tightly as possible so that there are no gaps through which the cold will penetrate. Remember that the transverse joints should not coincide;

• A film is placed on top of the insulation, and the surface is reinforced with mesh. The easiest and cheapest way is to use a special mesh for the screed, which is simply laid out on the base. There is no need to secure it additionally;

• The beacons are laid and the screed is poured. Here everything happens exactly the same as in the case above, so there is no point in considering this part of the work in detail.

If you decide to make heated floors, then the technology will be supplemented by the following steps:

• After the surface has been reinforced, the underfloor heating system is installed.. These works are described in a separate article, please read it if necessary:
• The beacons are placed and the screed is poured. Here you should remember only one thing: the minimum layer of solution above the heating should be at least 20 mm. This will ensure the strength of the surface.

Insulation of wooden floors

If you have a floor on wooden joists, then the workflow will differ from that described above.

First, let's look at what is needed to insulate a wooden floor:

• Board and block for the construction of rough flooring;
• Waterproofing material for the base under the insulation;
• Foam plastic, you can also use options with low density, since in this case there is no load on the material;
• Polyurethane foam for sealing all joints;

• Vapor barrier material for laying over insulation;
• A block for a counter-batten and a board or sheet materials for flooring.

The DIY process looks like this:

• If you already have a floor, you will need to remove it.. It is important to be careful not to damage the materials if you are going to put them back;
• A cranial block is attached to the bottom of the beams. Rough flooring boards, pre-cut to the required size, are placed on it. They are secured with nails or self-tapping screws;

• Waterproofing material is being laid. The film is spread over the beams over the entire surface; in order to fix it in the desired position, the easiest way is to use a construction stapler. For reliability, an overlap of 100 mm is made at the joints and the connection is additionally glued with tape;

• The wooden floor is insulated. Everything is simple here: the sheets are cut so that they fit as tightly as possible into the openings between the beams. If necessary, the heat-insulating material is laid in two layers, and the joints should not coincide;

• The gaps between the insulation and the beams are filled with polyurethane foam. It allows not only to ensure ideal thermal insulation of the surface, but also serves as glue, reliably fixing each element;

• Vapor barrier material is laid. Everything is simple here: the film is spread over the surface and secured with a stapler. Overlaps are made at the joints, and for reliability they can also be glued with tape;

• Lastly, the block is attached and the floor is laid on it.. The block is needed to create a ventilation gap to remove fumes from the structure. The floor is attached to a block, this can be a regular wooden board or sheet materials like plywood or oriented strand board.

Insulation using a solution with foam plastic

Polystyrene foam is sold both in slab and granule form. The bulk version is much cheaper and can be used to make a solution that will have good thermal insulation properties.

To work we need the following:

• Granular foam. It can be bought in the same place where sheet materials are purchased;
• Cement, it is better to take the M500 brand option;
• A concrete mixer, since you need to prepare a lot of solution and it will be difficult to mix such volumes with your hands.

This option is suitable for floor insulation in houses of any type; the work process consists of the following steps:

• First of all, the surface is cleared. It is necessary to remove all debris and protruding elements that may interfere with the work;
• Then waterproofing material is laid. For work, polyethylene film with a density of at least 100 Microns is used. It is laid in the same way as in the cases above - with overlaps on the walls and additional gluing of the joints for reliability;

• Installation of beacons, this process is described above, so we will not dwell on it;
• The solution is being prepared. To do this, first of all, prepare a mixture of cement and water to obtain a semi-liquid mass. Then granulated foam is introduced into the solution in a proportion of 3-4 parts of granules to one part of cement. All components are mixed well to obtain a homogeneous consistency;

• The mass is distributed on the surface, primary leveling is easiest to do with a shovel or wide spatula. The train should be located level with the lighthouses;

• . To do this, use a rule or an even strip of sufficient length. The better you level the floor, the easier it will be to carry out subsequent work;

• Final alignment is carried out. For work, a cement-sand mortar or a self-leveling composition is used. The second option is preferable, since with its help it will not be difficult to create a perfectly flat plane.

This option can be used both in a private house and in an apartment, when you need to make a thin layer and it is not possible to use sheet materials.

Conclusion

After reading this review, you can easily insulate the floor with polystyrene foam without outside help. The video in this article will help you understand the workflow even better, and if you have questions, write them in the comments at the bottom of the page.

Insulation of floors during renovation is the key to ensuring that the house will be cozy and warm, and you can even walk on the surface of the flooring barefoot without experiencing discomfort. And floor insulation is especially important in Russia, since the climatic conditions here leave much to be desired in most regions. You can insulate the base under your feet with a wide variety of materials, including isolon and mineral wool, which is often used in construction. But is it possible to use polystyrene foam for floor insulation? It turns out that it is possible, and this is one of the best insulation options.

Foam plastic is actually familiar to every person. And the scope of application of this material is quite extensive. But few people know what polystyrene foam is made of and what it actually is from a physical and chemical point of view.

So, polystyrene foam is light blocks of various sizes, consisting of foamed but pressed together granules of a substance such as polystyrene. During the production of the material, granules of this substance are treated with steam, the resulting particles undergo a drying stage, after which they are glued and pressed into a single block. And at the same time, 97% of foam is ordinary air. During the drying process, the foam acquires the same sound and heat insulating qualities that are familiar to us. The production of polystyrene foam is regulated by GOST 15588-66.

GOST 15588-86. Polystyrene foam boards. Technical conditions. Downloadable file (click the link to open the PDF in a new window).

Comparison table of characteristics of polystyrene foam and EPS

Comparative Thermal Conductivity Chart of Polystyrene Foam

Polystyrene foam has low thermal conductivity, which allows it to retain heat for a long time, thereby reducing heat loss in the house. Such indicators can be achieved precisely due to the porous structure of the material.

Polystyrene foam is not afraid of moisture thanks to a special production technology, when raw material granules are treated with moisture-saturated steam; it is resistant to the appearance of colonies of harmful microorganisms and mold growth. Fungus does not develop on it, which from a health safety point of view makes it one of the best insulation materials for walls and floors. The material also has a long service life and low weight, which is why they like to use it in construction. The material is easy to use, since, if necessary, it can be easily cut into elements of the required size, and you can drag the blocks yourself, without involving the help of third parties.

On a note! To ensure the proper level of thermal insulation of the floor, it is enough to buy very thin blocks of foam plastic - 10 cm of material thickness is enough to cope with this task.

Polystyrene foam is an inexpensive material, somewhat rigid and durable, does not require the construction of plywood structures for flooring, and does not require special skills or knowledge from the craftsman. This is an ideal option for coverings such as slats or parquet due to its soundproofing characteristics.

The main disadvantage of the material from a construction point of view is its requirement for the evenness of the base on which it will be laid. If this condition is not met, the foam will break and crumble, as a result of which it will lose its properties, albeit partially.

On a note! Polystyrene foam is often confused with expanded polystyrene, which is used for packaging various fragile products. In fact, these are somewhat different materials, although they have a lot of similarities. Packaging polystyrene foam is fragile, and its thermal insulation characteristics are much lower than those of polystyrene foam.

Table. Technical specifications.

Disadvantages of polystyrene foam

Polystyrene foam is far from an ideal material; it also has its own disadvantages, which you need to know about in order to draw your own conclusion whether or not to buy such material for floor insulation. The main ones are the following.

1. Low strength indicators. The material is easy to damage or break. But at the same time it is easy to cut.
2. The material is afraid of the effects of varnish or paint - it is destroyed because of them.
3. This is not a breathable coating, although it is full of air in itself.
4. If there are mice or rats in the house, they can greatly damage this type of insulation. Therefore, it is best to cover foam blocks with plaster.
5. This is not an environmentally friendly material, and if it is set on fire, it releases a huge amount of toxic fumes into the air. But the foam itself is absolutely safe for humans.
6. You still need to create a frame for foam plastic, but in the case of this material it can not be made as powerful as when using the same mineral wool.

Insulation of wooden floors

Wooden floors are quite common both in apartments and in private sector houses. They are environmentally friendly, easy to install and have good strength characteristics. However, on the lower floors, the relatively low thermal conductivity of wood is simply not enough to provide the proper level of heat, which means that the floors still need to be insulated. And here foam plastic would be an excellent option.

As far as we know, this is an entire structure that assumes the presence of an air gap between the plank covering and the ceiling. And it is precisely in this space that foam blocks need to be laid. Even a novice builder or a person who is far from construction, but decided to repair or simply insulate the foundation himself, can do this work.

In any case, the use of polystyrene foam requires careful preparation of the base. That is, it must be cleaned, leveled, and all cracks must be sealed. After this, a waterproofing coating is laid, on which the foam is then laid. But first, logs made of wooden beams are installed.

On a note! As waterproofing, you can use any material suitable for these purposes, even ordinary polyethylene film.

Foam blocks must be laid tightly, without gaps, and the joints between them can be foamed to reduce the number of cold bridges. Next, it is recommended to cover the foam with another layer of waterproofing.

Advice! To install insulation in a private home, it is better to buy foam plastic with a thickness of at least 10 cm. Moreover, the higher the humidity in the room, the thicker the insulating coating is used.

Insulation of the concrete base

Concrete floors are distinguished by high reliability indicators; they are usually very smooth and durable; they are not afraid of serious loads. However, it cools down quickly, does not retain heat, and the cold lets in easily. That is why concrete floors must be insulated. And here, too, polystyrene foam comes to the rescue. However, depending on whether there is a basement under the concrete floor or not, the insulation technology will also differ.

If there is a basement

This section is relevant for owners of private houses or those who have apartments on the ground floors. Concrete floors in these cases are quite cold, and even a good floor covering will not save you from discomfort. Here it is recommended to mount the insulation on the basement side, then the concrete slab itself, that is, the ceiling, will be in a layer of air and will better retain heat, and the cold will not penetrate into the house.

It is best to use foam plastic with a thickness of 5-10 cm, as is the case with wooden floors. If the concrete slab is uneven, then in any case it is important to prepare it for the installation of foam sheets. All cracks on it, if any, are sealed with polyurethane foam.

You can fix the foam on the concrete using dowels 12-14 cm long. You need to work slowly, drilling holes in the concrete with a hammer drill, marking places for fastenings. Before fixing the material, apply a special adhesive suitable for foam plastic to the surface of the concrete. The joints between fixed sheets can be covered with polyurethane foam.

Important! Polystyrene foam burns well and is easily damaged. Therefore, after installation, it is in any case important to protect it with plaster or ceramic glue using a thin reinforcing mesh.

No basement

If there is no basement in the house, and the apartment is located above the first floor, then another technology for floor insulation with foam plastic is used. In this case, the sheets are installed above a concrete surface. The old floor covering is completely removed, all cracks in the base are sealed, and the floor is leveled. It is best to seal cracks with thick cement mortar. Only after this is it produced with special compounds or materials. The easiest way is to use bitumen mastic, but in some cases roll material will also be convenient.

Afterwards, a reinforcing mesh or ordinary masonry is laid on the surface of the waterproofing. And only then sheets of foam plastic are placed on it. But here you can use thin sheets about 2-3 cm thick. The main thing is to install it with a minimum of joints so that cold bridges do not form. It is best to fix the foam with special glue.

Next, after laying the foam, it is done using a laser level. They can be fixed with the same mounting adhesive. Beacons are placed at a distance of no more than 1.4 m from each other, but at the same level. After this, a screed solution is poured over the foam - a regular concrete screed is performed, and the foam will be sealed on both sides with concrete surfaces.

Advice! You can level the surface of a concrete screed using a self-leveling mixture.

Foam plastic in floor construction on the ground

In private houses, in some cases, the first floor is not built above the basement, but directly on the ground. Here it is important to pay maximum attention to heat and waterproofing. It is best to lay not one, but two layers of thermal insulation material. The floor can be either above or below ground level. In any case, it is important to use the thickest foam possible when installing floors.

The base under such a floor must be carefully leveled and compacted. After which it is important to make a so-called cushion of gravel or crushed stone and compact it, and then cover the surface with a waterproofing coating. The best option is roofing felt. Next, the foam boards are laid very tightly to each other. Moreover, the joints of all seams should not converge in one place - it is better to lay the sheets in a checkerboard pattern. All joints between individual sheets are foamed.

Advice! The latest sheets should be taken slightly larger than the required dimensions in order to install them with some effort.

Then further waterproofing work is carried out again. You can cover the foam with a polyethylene film, but it is thick enough and durable. Next, the screed is poured using conventional technology. The thickness of the screed layer should not be less than 4 cm.

An example of floor insulation with foam plastic

Let's take a step-by-step look at insulating the floor in a house with polystyrene foam. This is a fairly simple option, and any person can perform such insulation.

Step 1. First of all, the rough base needs to be cleared of debris and all irregularities removed. If necessary, cracks are sealed and protrusions are ground. It is important to remember that polystyrene foam does not tolerate a crooked base. Next, a waterproofing layer is laid. In this case, roll material is used, which is laid in separate strips overlapping each other. In this case, the individual strips are fixed to each other by heating with a blowtorch. Waterproofing should be applied to the walls by approximately 10-15 cm.

Step 2. Next you need to install floor joists. In this case, they are wooden beams on which the floor under your feet will subsequently rest. Logs should only be used from dry wood. The lags can be fixed to the base using dowels. The step between the lags can be equal to the width of the foam sheet.

Step 3. After installing the joist, all communications that will be located inside the floor pie should be laid. This could be wiring, pipes, and so on. Laying should be done in accordance with the project of the house or renovation. As for the water supply, especially in a private house on the ground floor, it is best to place it on heat-insulating material.

Step 4. Next, you need to lay foam plastic on the surface of the waterproofing layer between the joists. It is laid consistently and tightly so that no gaps are formed. But if they appear, it is best to cover them with polyurethane foam. The logs should be of such a height that they are approximately 5-10 mm above the level of the laid foam.

Step 5. Then you need to “sew up” the floor pie with plywood sheets, OSB sheets or a regular board. That's it, the floor is ready, you can install the finishing floor covering.

Prices for foam plastic for insulation

polystyrene foam for insulation

Video - Floor insulation with foam plastic

Polystyrene foam is a truly convenient and practical, and most importantly, inexpensive material that is excellent for insulating floors in the house, as well as in any building. It is easy to work with, and the material performs its functions properly. So the main thing is to work without violating the technology, and then after installing such insulation in the house it will be comfortable and cozy.

A modern house is a structure that is subject to fairly stringent requirements for thermal protection. There are now a large number of highly effective thermal insulation materials on the market. They allow you to ensure comfortable temperature and humidity conditions in the premises. The most effective and reliable way to increase heat-protective characteristics is to insulate the floor with polystyrene foam.

The need for thermal protection and requirements for insulation

If a person is told that something needs to be done, he has every right to know why it is needed. If a house has insufficient thermal insulation of its structures, serious problems arise during operation.

The insulation performs the following functions:

• preventing freezing of the ground floor floor and penetration of cold into the premises;
• protection against condensation, which leads to the formation of mold, mildew and rotting of wooden house structures;
• the house will require lower heating costs during the cold period;
• increasing sound insulation characteristics.

The following requirements apply to the insulation used in the floor pie:

• good strength characteristics;
• resistance to moisture;
• resistance to rotting and molding;
• safety for humans;
• non-flammability;
• ease of installation.

All these requirements are met by extruded polystyrene foam, which can be used to insulate structures of concrete, wood, brick and frame buildings.

What is expanded polystyrene

Expanded polystyrene consists of styrene granules filled with gas. Air is the most effective insulation, so a large number of cavities allows the material to have good heat-protective properties. Currently, two types of expanded polystyrene are widely used in construction: polystyrene foam and extruded material. The second one is preferable to use.

These two materials look similar in appearance, but differ in their characteristics and manufacturing method. Polystyrene foam is made from polystyrene foam balls by sintering. In the production of extruded polystyrene foam, granules are mixed with a foamed reagent and pressed through an extruder.

What's better? Polystyrene foam or extruded polystyrene foam?

Polystyrene foam has only one advantage compared to extruded material: low cost.

If a house is being built without severe cash constraints, it is better to choose the second option.

If we conduct a comparative analysis, we can come to the following conclusions:

• extruded polystyrene foam has high strength and works better in floor construction;
• polystyrene foam is characterized by higher water absorption (about two times);
• in the presence of moisture and exposure to low temperatures, the foam may crumble into individual balls;
• polystyrene foam is a medium- and low-flammable material and, when exposed to high temperatures, releases substances hazardous to humans;
• Thanks to special additives, extruded polystyrene foam becomes fire resistant.

Best suited for insulating the floor of a wooden house extruded polystyrene foam. To reduce construction costs, you can apply floor insulation with two types of polystyrene foam at the same time. The lower thick layer of greater thickness is made of polystyrene foam, and the upper one is made of a more durable material 3-5 cm thick. This method allows you to achieve a compromise between price and quality.

Wooden house floor pie

Depending on the strength, the material can be laid in two ways: without logs and with their help. In the first case, the weight of the entire structure of the finished floor falls on the insulation, so a cement-sand screed is made on top of it. We have already looked at it in detail earlier. Most often, this method is used for the floors of brick and concrete buildings.

For a wooden house, insulation is carried out between wooden joists. It is important to take into account the location of the insulation in the building - the thermal protection of the attic floor differs from the insulation of the floor above a cold basement or underground.

Please note that the process is slightly different from the above method.

In the first case, the layers are laid in the following order:

1. wooden floor;
2. vapor barrier;
3. insulation.

When used in construction first floor floor The installation order is as follows:

1. wooden floor;
2. waterproofing;
3. insulation;
4. vapor barrier.

When using extruded polystyrene foam, a vapor barrier need not be installed.

For polystyrene foam, it is important to remember that protection from steam is located on the warm air side, and protection from moisture is located on the cold air side. Only in this case will the house be reliably protected from the penetration of cold air. As a vapor barrier and waterproofing, you can use ordinary durable polyethylene film.

Installation process

Depending on the installation method, work can be carried out in different ways.

The minimum layer of insulation depends on the climate in which the house is located, but on average it is 10 cm.

Laying insulation without joists (under screed)

The work process begins with cleaning the base from dirt and dust. Next, if necessary, perform alignment. After preparing the base, the slabs are laid out, taking into account the gap for thermal expansion. These gaps are filled with fiberglass or polyurethane foam. With this installation method, a cement-sand screed is placed on top of the insulation. For fragile foam, it must be additionally reinforced.

Laying between joists

The process starts with log installations, the pitch of which is selected depending on the size of the insulation boards.

This method does not require high strength, so you can safely use polystyrene foam.

Between the logs, depending on the structure being protected, it is laid vapor barrier or waterproofing. The plates are mounted in the same way as in the previous case, with a small gap. After installing the insulation, construction of the structure begins finished floor.

Schemes for constructing a floor pie are given in this article above.

Floor insulation with expanded polystyrene can significantly reduce the load on the building structure. This is especially important if the house is being built on unstable soils with poor characteristics, since it allows you to avoid overloading the foundations.

If you follow all the rules for laying polystyrene foam, it can protect your house from the cold for 40-50 years. The correct choice of materials and quality control of work can reduce the costs of operating and repairing a home.

This video clearly describes insulation using this method: