Floor insulation with expanded clay: pros and cons. Is it possible to fill expanded clay without waterproofing?

The socket has two phases
11.08.2023

Quite a few city dwellers are thinking about purchasing or have already become the happy owners of several acres of land in the suburbs, away from noise, dust and smog. An indispensable attribute of free country life is a house - a massive brick one or, elegant in its simplicity, a wooden one.

Despite the visible advantages of wooden houses, such as beauty, environmental friendliness, and relatively low price, a lot of effort and money is required to invest in systems for hydro-, steam- and thermal insulation of walls, roofs, floors, windows and doors. Insulating the floor with expanded clay in a wooden house is the simplest and cheapest way to conserve heat and walk around barefoot to your heart's content.

A few facts about expanded clay

Expanded clay has been successfully used as floor insulation for decades. Even the emergence of new insulation technologies did not affect the popularity of this unusually light porous material made of baked clay.

In addition to the price acceptable to almost everyone, expanded clay is characterized by the following valuable properties:

  • High level of thermal insulation. Compared to wood, expanded clay retains heat three times better;
  • Resistance to temperature changes - expanded clay is not flammable and does not collapse at extremely low temperatures;
  • Environmentally friendly - the insulation is absolutely unattractive to rodents;
  • Easy to transport and install.

The quality of expanded clay directly depends on the accuracy of production technology. During the technological process, low-melting clay is subjected to a sharp thermal shock, as a result of which it swells and becomes porous, and the surface of the granules melts, imparting resistance to external influences and strength. Thus, each expanded clay granule is enclosed in an almost hermetic shell.

Based on granule size and structure, expanded clay is divided into types:

  • Gravel, with grain diameter from 5 to 40 mm;
  • Sand – up to 0.5 cm;
  • Crushed stone - grain sizes can be different, since the material is obtained by crushing gravel into large fractions.

Where is expanded clay used?

Expanded clay for floor insulation is an ideal and inexpensive option. Its installation does not require special knowledge and skills and can be done by anyone.

It has been proven that a layer of this material just 10-15 cm thick reduces heat loss by 60-70%. Expanded clay sand is an ingredient in dry mixtures for a wide range of applications, used for insulating walls, foundations, etc. It is also often backfilled and compacted under parquet flooring.

The instructions below will tell you how to insulate a floor with expanded clay with your own hands.

Sequence of actions when insulating a floor with expanded clay

  1. The first step is removing the floor covering: linoleum, parquet, laminate or floorboards. All fasteners are also removed, leaving only the logs if they are still suitable for further use.

  1. Next, the sand cushion is filled, leveled and compacted. layer of at least 10 cm;
  2. The pillow is covered with a layer of waterproofing. Usually this is a thick polyethylene film. Ideally, it will be distributed as a single sheet over the insulated area.
    Otherwise, the joints are hermetically sealed with construction tape. The edges of the film should be on the walls. The height of the overlap is necessarily a couple of centimeters higher than the expected thickness of the expanded clay layer;

  1. Determining the level of the future floor and placing beacon guides. Beacons are placed on alabaster or gypsum mortar. After it has completely hardened and the final level has been checked, you can fill in the insulation;

Note!
If you do not have a construction education or experience in insulating with expanded clay, then to calculate the thickness of the thermal insulation layer, it is better to seek help from professionals; they will accurately determine the value of the thermal resistance of the room.
Remember that the thickness of expanded clay for floor insulation must exceed 10 cm.

  1. Expanded clay backfill. Expanded clay is distributed over the waterproofing in a layer of the required thickness; the evenness of the surface is determined by the level or rule.

Advice!
Insulation of the floor in a wooden house with expanded clay should be carried out by mixing at least two fractions, this will ensure the best compaction of the insulation and protect it from further shrinkage.

  1. This step prepares the floor for subsequent pouring.. Before pouring, expanded clay is generously moistened with so-called “cement milk”, prepared from a mixture of water and cement. This measure facilitates the process of pouring concrete or cement mixture, preventing the movement of expanded clay granules.
  2. A possible, but not obligatory step is reinforcing the floor with metal mesh. The reinforcement minimizes potential deformations, and hence the destruction of the screed.
  3. Filling is done carefully and carefully. Try not to make any holes in the insulation with the solution, otherwise the floor will have to be leveled additionally later.

The strength gain and complete hardening of the poured coating occurs only 28 days after pouring, although you can walk on and beyond without fear within a week.

For your information!
You can check the progress of the hardening process using a regular glass jar. If you place it upside down on the screed and it fogs up, the floor is not dry yet.

As you can see, insulating floors with expanded clay if you follow the builders’ recommendations is a completely feasible task. The result of your work will be a smooth and warm floor, which you can decorate to your liking.

Summary

We told you about insulating the floor in a private house with expanded clay, about the advantages and types of this universal and environmentally friendly material. In the video presented in this article you will find additional information on this topic. We hope that our advice will help you choose the right thermal insulation material and install it correctly.

Supporters of using environmentally friendly materials in construction for floor insulation can easily use expanded clay. This thermal insulation material is called the most natural, which is not surprising: it is made from clay and rocks containing slate by rotating the raw materials in a hot oven. Under the influence of high temperature and centripetal force, the rock is sintered and granules of different sizes are formed. In fact, insulating a floor with expanded clay means not only using a material that is harmless to health, but also reducing the cost of construction, since, firstly, the material itself is cheap, and secondly, working with it does not require a lot of time and special equipment.

There are several construction technologies for using granules: introducing them into a concrete screed or pouring expanded clay around the perimeter of the floor, roof or into the spaces between walls. Let's consider both options for using expanded clay for floor insulation.

Expanded clay in concrete mortar: a popular but controversial method of insulation

A fairly common method of constructing a floor using a mixture of expanded clay and cement. Among other advantages of this particular option, floor screeds indicate an improvement in the thermal insulation properties of such a floor. However, it should be clarified that the advantage of expanded clay as an isolette is the presence of air bubbles in its granules (for production, a special type of clay is taken that foams during firing).

Expanded clay under the influence of high temperatures and centrifugal force is formed into durable granules of different sizes

This is important to know
The heat-saving qualities of expanded clay differ in different brands. Granules that have a more porous structure retain heat best. Such expanded clay can retain up to 80% of heat.

By introducing expanded clay into an aqueous cement-sand solution, we obtain a material in which air is partially replaced by water, as a result of which its heat-saving qualities are significantly deteriorated. But, all of the above does not mean that expanded clay concrete screed does not insulate floors. It insulates, but is slightly worse than a layer of bulk dry expanded clay. The following reasons are given in favor of adding it to concrete mortar:

  • where the floors are very uneven and the required screed height is large, it is impossible to do without introducing filler into the solution, and expanded clay is best suited for this;
  • It is more convenient to work with granules as part of a solution, rather than in bulk.

Some secrets of laying expanded clay concrete screed

The ratio of the cement-sand mixture to the filler should be approximately 2:1, and its consistency should be close to a thick dough. Even experienced builders do not risk naming exact proportions, citing differences in cement grades and types of expanded clay granules. A sign that the ratio of ingredients is correct will be the coating of all granules with the solution.

Expanded clay concrete screed is of high quality if all the granules are enveloped in the solution

Lighthouse slats are installed on the floor using plaster. The solution is applied with a trowel and leveled using a rule - a special board. If the top covering is an ordinary concrete floor, then a screed made of simple concrete mortar is laid on top of the expanded clay, without waiting for it to dry. The floors dry out after a couple of days, but the floor covering should be laid no earlier than after a month.

Expanded clay in bulk: how to lay under concrete and wooden floors

Expanded clay as an insulation material is excellent for concrete and wooden floors. The methods in which it is laid in these two cases are somewhat different from each other. In the first case, loose granules of insulation should be fixed in place so that they do not move during subsequent laying of the screed. In order to insulate wooden floors, expanded clay is spread in an even layer between the joists and leveled. The main thing is that its layer is at least ten centimeters.

This is important to know

In order for the expanded clay granules to fit into denser layers and be less friable, you should purchase material of different sizes. In this case, large and small granules will have better adhesion.

How to lay material granules under a concrete screed

Let us tell you in more detail the stages of installing concrete floors with their insulation with a layer of expanded clay:

  • Floors can be laid directly on the subgrade. To do this, it is compacted, a sand cushion is made and a layer of gravel is poured. This is preparation for subsequent floor installation.
  • Expanded clay crumbles and levels, without elevations in one direction or another. It is more convenient to do this using a laser level device.

This is important to know

The expanded clay layer must be insulated from moisture from below. Even when laying it not on an earthen floor, but on a wooden base, you should first lay the film. Its height on the sides must be calculated so that it rises above the expanded clay by several centimeters.

The concrete solution is applied to a layer of expanded clay and leveled using the rule along the lighthouse slats

  • In order to avoid shifts during subsequent pouring with concrete mortar, the top layer with granules is fixed with liquid cement mortar. If a large load is placed on the floor in the future, then a reinforcing mesh is placed on top.
  • The screed solution is applied to a layer of expanded clay and leveled along the lighthouse slats using a long rule.

The solution contains cement and sand in a ratio of approximately 1:3 or 1:4 (depending on the brand of cement and the time of its manufacture: the older the cement, the less sand you need to take). Often, various types of plasticizers and other fillers are added to the screed, which add convenience during work and improve the quality of the floor.

Why expanded clay is used for insulation: properties and advantages of the material

Among the characteristic features of expanded clay are the following:

  • baked clay and air-filled cavities of granules can perfectly insulate against the penetration of cold from the soil and prevent heat from escaping from the room;
  • the material is resistant to temperature changes;
  • has increased fire resistance;
  • able to withstand severe frosts without losing its qualities;
  • absolutely harmless to all living things, as it is produced without the use of chemicals and from natural materials;
  • Expanded clay, among other things, makes structures lighter and insulates from the penetration of sounds.

It is not surprising that from the beginning of the twentieth century, when expanded clay began to be widely used on construction sites, to the present day its demand continues to be high. And this is despite the breakthrough in technology, when hundreds of high-tech materials appeared. In a word, cheap and “modest” expanded clay remains an indispensable material for insulating floors and other building structures.

In order for the home to be comfortable, it is necessary to take care of additional insulation of the walls, roof and floor. Thanks to such work, you can not only create comfort, but also significantly save on heating the room in the future. Where is it advisable to use expanded clay? As an insulation material for vertical and horizontal surfaces, it is widely used in private homes and industrial buildings. This option is considered the best and financially justified.

Expanded clay: what is it?

This building material is fairly light granules with small pores. They are obtained by It can be used both in private houses and in standard apartments located in high-rise buildings. Expanded clay is environmentally friendly for human health, as it does not contain any synthetic additives or harmful substances that can be harmful and lead to harmful consequences. It allows air to pass through well, which prevents moisture condensation. Expanded clay insulation (people's reviews allow us to judge its quality) first of all has good thermal insulation. It also acts as a noise-absorbing material and has a high level of frost resistance and is not destroyed by temperature fluctuations. The service life of expanded clay is quite long; in terms of this indicator, it has no equal among other materials. It is worth noting that this insulation is not at all afraid of prolonged interaction with hot and cold water. Therefore, there is no need to be afraid that after a flood you will have to completely change the base of the floor.

Types of expanded clay

Expanded clay is used quite often as insulation in construction. However, you need to know that, depending on the scope of application, it is necessary to choose a certain type of material. As a rule, three main varieties can be distinguished.

The first, sand, is most often added to dry mixtures that are intended to be applied to surfaces in order to create a thermal insulation layer. The maximum size of its granules is 5 mm. This type can also be used to create a heat and sound insulating cushion, which is compacted under the main covering.

Please note: a layer 15 cm thick allows you to save 50% on heating.

Expanded clay, as an insulation material (reviews are mostly positive), in the form of granules is used not only for floors, but is also widely used for roofing and ceilings. Owners of private houses give preference to this fraction when it comes to an attic or attic.

Expanded clay in the form of crushed stone is finely crushed gravel. The grain sizes are different. Thanks to this, the compacted layer is as functional as possible. Consumer reviews give the right to judge its high quality and properties. It copes well with its main purpose even in the coldest rooms.

Properties of expanded clay as insulation

The main indicator of this material is its natural clay composition. After high-temperature treatment, it becomes quite strong and reliable. It is worth noting that by using it in garages and basements, you can forget about such a problem as rodents. At an average cost, it has a long service life. And in comparison, for example, with wood, it is significantly better, since it does not rot, does not create a favorable environment for insects, and is not at all afraid of humidity and even prolonged exposure to water.

The properties of expanded clay as insulation are multifunctional both in winter and summer. It is considered the most versatile material, which has a high level of frost resistance and copes well with exposure to high temperatures.

The main property of this material is the complete absence of toxicity. Also, importantly, expanded clay does not create a favorable environment for mold, mildew and other pathogenic bacteria. Due to the fact that it does not enter into chemical reactions with aggressive substances, such a coating completely eliminates the possibility of the formation of harmful vapors that can adversely affect human health.

Expanded clay guarantees excellent thermal insulation for both the foundation and the roof. Thanks to its use, the house will faithfully serve for many years. Let's consider the advantages of insulation

Reviews from consumers who have already used expanded clay to insulate their homes allow us to highlight its main advantages.

Let's discuss the disadvantages

Like any other material used in construction, expanded clay has some disadvantages:

  • In private houses, garages and basements, the layer thickness should exceed 50 cm, otherwise there will be no benefit from such a pillow at all.
  • In very damp rooms, expanded clay is completely unsuitable as floor insulation. Feedback from people allows us to draw these conclusions. However, the above-described drawback can be corrected using a special waterproofing film.

Scope of expanded clay

The scope of application of this material is quite large. First of all, it is a common material for It is in this place that it is considered the most ideal and financially acceptable. But for comparison: expanded clay as wall insulation (reviews help to conclude that this method is unprofitable) is used quite rarely. Some may say that nowadays manufacturers have developed special heated floors. And so it is. However, their cost is quite high, which makes this option practically inaccessible. But expanded clay, on the contrary, is easy to install and at a price suitable for any family with average income.

Depending on the base of the floor, the appropriate insulation method is selected:


Wall insulation using expanded clay is also used in construction. Basically, this method is acceptable in newly erected buildings. It consists in using a certain three-layer method, where the main layer consists of capsimet (a mixture of expanded clay with cement laitance).

Due to its light weight, this material is widely used for insulating roofs, attics, and attics. This method will not lead to an increase in the load on the foundation and, as a result, will not require additional financial costs for strengthening. Expanded clay as ceiling insulation is used in a unique way, that is, from the attic side, using the floor insulation method. The main advantage of this option is the absence of leaks and mold formation.

Insulation of earthen soil is also quite important; it is very often used in greenhouses for growing seedlings, seedlings, etc.

Expanded clay production technology

Some types of clay, which melts easily, are placed in a special chamber. In it it softens to a dough-like mass. After this, using high temperatures (over 1000 0 C), it is heated to boiling. It is this process that leads to the formation of porous granules. The more there are, the higher quality the expanded clay is considered. Here the raw materials remain until completely cooled. After which it is sorted and prepared for transportation. Expanded clay granules are produced in this way. However, if sand is needed, then the finished material is ground into small particles using a press. Crushed stone is produced in a similar way with the only difference: expanded clay granules are crushed into several parts. Their sizes are mainly different, which allows you to get a better result when filling.

Floor insulation technology

Expanded clay can be used as floor insulation only after special preparatory work has been carried out. There are several required steps:

  1. Preparation. It is necessary to completely remove the old coating. Based on reviews from people who have already used this method of insulation, wooden floors are disassembled down to the fastening structure. If the joists are in good condition, they can be left.
  2. Forming a sand cushion. It must be at least 10 cm thick. Before laying subsequent layers, the sand is carefully compacted.
  3. After this, expanded clay is poured. It is recommended to immediately determine the thickness of its layer, since the thermal insulation effect will depend on this parameter.

All work is carried out strictly according to guidelines in order to maintain the evenness of the floor covering. If all steps are carried out with precision, then a good result is guaranteed.

Where to start insulating the floor with expanded clay?

Before you start insulating the floor, you need to familiarize yourself with all the nuances. Expanded clay as a floor insulation (people's reviews confirm this information) is considered the most ideal option, but only if installed correctly.

So, let's take a closer look at what you need to know to get the desired result:

  1. Determination of the material from which the floor base is made. This criterion is quite important, since its thermal conductivity fully affects the overall indicator.
  2. Calculation of the thickness of the expanded clay layer. For clarity, we can give the following example: a concrete slab with the addition of expanded clay 60 cm thick will provide the same warmth as a meter of brickwork.
  3. Planned load. The floor is the only surface that is constantly exposed to mechanical stress. Therefore, it is necessary to take this parameter into account at the planning stage. When calculating what the expanded clay layer should be, the main thing is to avoid mistakes, so it is recommended to contact specialists to make accurate calculations.
  4. Don't forget about the waterproofing layer. There are several features in which expanded clay without this layer will not be effective.

You also need to remember that an expanded clay pillow acquires maximum properties with a width of at least 15 cm

If the floor insulation work will be carried out independently, you need to take note of several important recommendations, which are compiled based on customer reviews:


Roof insulation

Expanded clay has been used for roof insulation for quite some time. Of course, many competing materials have appeared in this area over such a long period, but it has not yet been possible to completely replace natural materials. It is by using expanded clay as a floor insulation (look for truthful reviews on the information stands of manufacturing companies) that you can fully judge all its advantages.

First of all, thanks to this material it becomes possible to completely eliminate problems with condensation. The formation of steam and moisture is reduced to zero. Also, importantly, the roof will be protected from leaks for a long time. The light weight of the material will allow you not to spend money on additional strengthening of the foundation. And this is some kind of quite significant savings. If you involve professionals in the work, the end result will please the owners not only with warmth and comfort, but will not require financial investments for reconstruction for a long time.

The content of the article:

Insulating a floor with expanded clay is one of the most well-known methods of thermal insulation. Many synthetic heat insulators that were previously in demand are being replaced by natural insulation materials that are safer for humans and pets. Considering the relatively low cost of the material and consumables, it is not surprising that it has earned such popularity.

Features of floor insulation with expanded clay

Expanded clay is a natural insulation material because it is made from clay and shale-containing rocks containing no more than 30% quartz in its base. During the manufacturing process, raw materials are subjected to heat treatment in special ovens. The temperature affects it in such a way that it sinteres and forms granules of various sizes.

During production, it is not possible to produce granules of the same size. Therefore, expanded clay is divided into the following fractions: sand - 5-10 mm, crushed stone - 10-20 mm, gravel - 20-40 mm. The material is characterized by its low weight and porous structure.

Experts recommend it as a reliable and effective heat insulator, since it is not only harmless to the health of the inhabitants, but also reduces the cost of insulation, as well as further maintenance of the building. Which expanded clay is best for floor insulation depends on the type of building and its purpose. To achieve the maximum effect of thermal insulation with this material, the characteristics of the floor surface on the first floors of buildings are taken into account.

When making calculations, it is necessary to take into account that this layer of only 10 cm has an effect that is equal to 20 cm from wood insulation. Whether to fill expanded clay around the perimeter of the insulated floor or mix it with a concrete screed is up to each owner to decide for himself.

If you are interested in how to insulate a floor with expanded clay, pay attention to its basic properties in combination with other materials. One of the common methods of thermal insulation is mixing cement with expanded clay granules. As practice shows, this option improves the insulation characteristics of indoor floors. On the other hand, the main advantage of this material is the presence of air bubbles in it, which are obtained during its production.

When we insulate the floor with expanded clay with our own hands, mixing granules with cement-sand mortar, we achieve a deterioration in its thermal insulation qualities due to the presence of water in the composition. That is why professional construction teams in many cases prefer the dry insulation method. But the use of wet solutions is in demand in those facilities where the floors have significant differences and it is necessary to level them with a new concrete screed. In addition, it is much easier to work with solutions than with dry expanded clay.

It is important to know! Granulated expanded clay must be laid so that it is reliably isolated from moisture that can enter from below. Even in cases where the heat insulator is not placed directly on the earthen base, it is impossible to do without covering it with a waterproofing film. The height should be such on both sides that it rises several centimeters above the insulation.

Advantages and disadvantages of floor insulation with expanded clay


The main positive characteristics of this insulator are as follows:
  • It is completely harmless to humans and pets, since no chemicals are used in its production, but only exclusively natural materials.
  • In addition to its heat-insulating qualities, it acts as a good barrier against the penetration of extraneous noise and sounds into the room.
  • Expanded clay is characterized by increased fire resistance and resistance to significant temperature fluctuations.
  • It perfectly withstands even the most severe frosts, preventing heat loss from the building.
  • Simple installation technology makes it possible not to involve outside specialists at the stage of such work.
  • Expanded clay is practically not subject to physical, biological and chemical effects.
  • You can achieve different thermal insulation values ​​by changing the size of the material fractions.
There are, of course, certain disadvantages that characterize floor insulation with expanded clay. Firstly, it is quite high fragility, which it owes to natural raw materials. This can significantly complicate the creation of an insulating layer. Therefore, it is necessary to lay expanded clay with the utmost care so as not to disturb the structure of the granules - otherwise this will lead to a violation of the insulating qualities.

Secondly, it is worth mentioning the moisture-absorbing characteristics, which can also be a real disadvantage. This is due to the fact that the granules only absorb moisture, but do not release it outside.

Another negative quality is the thickness of expanded clay. It automatically leads to the creation of a fairly thick insulating layer. Consequently, such thermal insulation is not entirely suitable for rooms with low ceilings, because the volume of space will be significantly reduced.

Expanded clay floor insulation technology

These works are not particularly difficult if you carefully follow the recommendations given here. This does not require construction qualifications, but you must adhere to the specified algorithm.

Preparatory work before installing expanded clay


Before proceeding with thermal insulation, it is necessary to carry out a number of works to prepare the floor surface. This may include the removal of old flooring, old joists, and fastening structures. You can leave all this only if the wear of the elements allows them to be reused.

If we are talking about insulation on a soil base, then it is first carefully leveled and then compacted. A layer of gravel or crushed stone approximately 30 cm high is laid on it. A 10 cm layer of sand is poured on top of these materials.

For concrete bases, it is enough to remove protruding folds using a grinding machine with attachments for working on concrete. Pits and depressions are filled with leveling mixtures or putty.

After this, the floor is cleaned of debris, particles and dust, and wet cleaning is performed. Once the surface is completely dry, it is coated with 2 layers of primer. The base is ready for insulation.

For country and cottage-type houses, it is best to opt for insulation using joists.

Instructions for installing expanded clay on the floor


As for expanded clay fractions for floor insulation, to achieve greater efficiency it is necessary to mix heterogeneous, that is, granules of different sizes. Therefore, large pieces of material alternate with small ones in the same space. This is also due to the fact that large granules are less compacted on their own.

The very essence of floor thermal insulation with expanded clay comes down to the following:

  • Before pouring granules onto the floor, it must be waterproofed. Even ordinary plastic film can be used for these purposes. The joints on the panels are fastened using ordinary tape - this is necessary to ultimately obtain a single canvas.
  • To carry out insulation, it is necessary to obtain a perfectly flat surface of the site. To achieve its leveling, the level of the future floor is marked with construction beacons before filling. The first is installed at a distance of 2-3 cm from the wall. All subsequent ones are placed in a parallel line, thereby achieving a single screed. To fix the beacons, you can use cement mortar.
  • After all the guides are aligned, begin filling in the expanded clay granules. The insulation layer should be as even as possible and free from irregularities and differences.
  • To ensure that the expanded clay is securely fixed, it is filled with cement mortar. It will give the future layer the necessary strength.
  • In some cases, it may additionally be necessary to use reinforcing mesh. It will be able to give the entire structure a single whole and reduce the risk of deformation of the insulated coating.
The complete hardening time of the poured floor is from 7 to 10 days, after which it will be possible to move freely on it.

Pouring concrete screed


After the expanded clay insulation is laid, it must be covered with a concrete screed. It will not only add strength and fix the top layer, but also provide waterproofing on top.

But first, another intermediate layer is poured. It is made from a mixture of cement and water, which form a kind of suspension. It should be neither too liquid nor too dry. This layer is necessary to displace air with cement from air pores. The result is a monolithic coating that will not be subject to heavy loads or excess moisture.

Now you can move on to the final screed, which will not only level the insulated floor, but also prepare it for laying any floor covering.

The quality and strength of the entire assembled structure will depend on the quality of the prepared solution. In other words, this is the quality of sand and cement, as well as their proportions in the mixture. A lack of cement leads to weakening of the strength, while its excess leads to the solution hardening too quickly.

The optimal ratio is considered to be: 1.5 parts of cement to 1 part of sand, while water should not exceed 20% of the resulting volume of dry matter. It is added by eye, and then mixed until a homogeneous solution is obtained, which is poured on top of the expanded clay.

The coating is leveled evenly over the entire layer of heat insulation using a large spatula, and as a result, a so-called “coupling mirror” is formed.

The following recommendations will help you perform a correct and effective screed that perfectly levels the floor:

  1. It is important to prepare the potting mixture in the required proportion.
  2. Drafts and excess moisture should be eliminated whenever possible.
  3. The mixing installation and working containers for solutions should be prepared in advance, and you should also ensure the operability and safety of the equipment.
  4. The base level of the floor is measured, after which calculations are made to determine the height of the future screed.
  5. The layers must be applied in sequential order.
  6. In order to control cracks, cuts with a spatula can be used, if necessary.
The technology of floor insulation with expanded clay followed by installation of screed requires complete drying of the poured surface before final finishing. This allows for the necessary connection of materials. To do this, it must be covered with any protective materials - sheet cardboard, plastic, etc. will do.

Finishing of insulated floor


One of the promising options for finishing a thermally insulated floor could be laying parquet with subsequent varnishing. True, not every owner can afford this technology due to the high cost of wood. It is necessary to invite experienced craftsmen to lay parquet flooring, since it requires special sanding machines and installation skills.

To give the finished look to the laid parquet, it is sanded. The baseboards are installed and the coating is coated with varnish or oil. Parquet scraping followed by sanding occurs in several stages using machines equipped with various attachments. For example, rough processing is used to eliminate differences between adjacent parquet boards, as well as to remove dirt. After this, grinding is carried out, as well as processing of hard-to-reach places, in particular under the elements of the heating system, etc.

The varnished and painted baseboard is nailed to the walls after giving them their final look: wallpapering, painting, paneling. Skirting boards are nailed with special nails, which are driven and hidden in wooden plugs.

The last stage will be finishing the parquet. This can be varnished or oiled. This layer not only gives the floor an attractive appearance, it reliably protects it from moisture, household pollution and other influences that lead to accelerated wear of the parquet. You cannot wash parquet boards without varnish or oil, but after coating, excess dirt and dust can be easily removed from them with a damp cloth.

When working with parquet, it is necessary to use protective equipment such as masks and a respirator, and the doors and windows in the room must be open to effectively ventilate harmful fumes. It is necessary to wait between varnishing operations.

As soon as the first layer has dried, the surface is thoroughly cleaned with sandpaper. Dust must be collected with a vacuum cleaner and dry rags, after which a secondary varnish coating occurs. After it dries, the product is applied for the third and last time.

During use, the varnish layer gradually wears away and becomes covered with cracks and scratches. Therefore, it must be restored every few years. It is enough to cover the most worn areas of the parquet with oil, but in the case of varnish, sanding may be necessary to remove dirt and remnants of the previous varnish.

How to insulate a floor with expanded clay - watch the video:

For passionate supporters of the use of environmentally friendly materials in construction, the question of whether expanded clay can be used for floor insulation will probably seem strange - of course, yes! For its production, absolutely natural materials are used - clay and shale rocks, which are sintered and granulated in a rotating cylindrical kiln at high temperature. The result is granules of different sizes.

  • More about expanded clay
  • Varieties of expanded clay
  • Which expanded clay is best for floor insulation?
  • Advantages and disadvantages of expanded clay
  • Methods of insulation with expanded clay
    • Dry insulation with expanded clay
    • Wet laying of expanded clay
    • Combined method
  • Insulation with expanded clay under a wooden floor on a concrete base
    • Materials and tools
    • Dismantling the coating
    • Surface preparation
    • Waterproofing
    • Installation of logs
    • Expanded clay backfill
    • Flooring installation
  • Insulation with expanded clay under a wooden floor on the ground
  • Insulation with expanded clay under a concrete base
    • Floor preparation
    • Expanded clay backfill
    • Reinforcement
    • Performing a screed
  • Expanded clay concrete screed

But expanded clay is good not only for its high environmental friendliness. It should also be noted its low cost in comparison with other insulating materials, as well as the ease and speed of its application, because this does not require any special equipment.

More about expanded clay

The word "expanded clay" has Greek roots and is translated as "burnt clay." This material is extremely light, has a cellular porous structure, and its granules are round in shape. During the firing process, low-melting clays, to which peat, sawdust and diesel fuel have been added, swell. Expanded clay is often used in construction as a filler in concrete in cases where it needs to be made lighter.

The thermal insulation properties of expanded clay are affected by:

  • granule size;
  • granule strength;
  • density of the material.

Based on bulk density (or volumetric weight), there are 10 grades of expanded clay (from 250 to 800). The brand number hides the bulk weight of the material, expressed in kilograms per cubic meter. For example, a cubic meter of expanded clay grade 250 weighs exactly that much in kilograms.

The greater the porosity of the material, the lower its density and the higher its thermal insulation properties, which is very important when choosing which expanded clay is best for floor insulation.

Different bulk densities are obtained with different methods and modes of processing the feedstock. Bulk density is determined by filling special measuring vessels. Typically, the largest fraction has the lowest volumetric weight.

Varieties of expanded clay

Expanded clay sand

It is formed after firing clay residues or by grinding large fractions of expanded clay. The particle sizes here are no more than 5 mm. This sand, together with large fractions, is used for insulating interior partitions or when floor insulation with expanded clay concrete is required. It also serves as a filler for cement mortar.

Expanded clay gravel

It consists of rounded grains 5-40 mm in size with a porous structure, which are obtained in pyrogenic furnaces when superfusible clay is expanded. It is fire-resistant, frost-resistant and water-resistant material.

Expanded clay crushed stone

It is angular, has no definite shape, and is similar in size to gravel. It is obtained by crushing large pieces of expanded clay, and is used together with other types to produce lightweight concrete if the concrete floor is to be insulated with expanded clay.

Which expanded clay is best for floor insulation?

When classifying expanded clay, the size of its granules can be chosen as a basis. The division into factions is as follows:

  • The fraction from 5 to 10 mm is used for the production of expanded clay concrete blocks and when pouring screeds.
  • Granules from 10 to 20 mm are the answer to the question of what fraction of expanded clay is used to insulate floors or ceilings in houses.
  • Fractions from 20 to 40 mm are used to insulate basements, roofs, garage floors and heating mains.

If you put the second and third fractions into the screed, its thickness will increase.

Advantages and disadvantages of expanded clay

Advantages

The advantages of expanded clay include:

  • good thermal insulation and sound insulation;
  • fire resistance;
  • high strength;
  • durability;
  • frost resistance;
  • environmental friendliness.

Floor insulation with expanded clay under a screed can be chosen for a number of reasons:

  • Expanded clay is exceptional in that it can be poured onto any base, even onto the ground, on which foam or mineral wool cannot be placed directly, as they will quickly lose their useful qualities.
  • Expanded clay has the greatest strength among other insulation materials.
  • The environmentally friendly composition ensures that expanded clay is safe to use, since it does not release anything into the air.
  • Due to its non-flammability, expanded clay has no restrictions in terms of fire safety; it can even serve as a barrier to open flames.
  • Expanded clay is the cheapest insulation material, so insulating floors with expanded clay in a private home, as well as walls and ceilings, has long been widely used. In addition to private buildings, it is widely used in industrial and other buildings.

Flaws

A significant disadvantage of floor insulation with expanded clay is its strong hygroscopicity. When its granules are actively saturated with water, they completely lose their heat-protective properties, and do not release moisture back for a long time. Damp, heavy expanded clay begins to sag, and unevenly, which leads to deformation of the floor, which must be taken into account if insulation with expanded clay and screeding of the floors of the 1st floor are carried out. To avoid this, when installing floors, you need to carry out reliable waterproofing.

Methods of insulation with expanded clay

Builders use three methods of adding expanded clay:

  • wet;
  • dry;
  • combined.

To make the technology of floor insulation with expanded clay more understandable, you should understand each option in more detail.

Dry insulation with expanded clay

This is how floor insulation is usually done with expanded clay in a wooden house.

  1. The material is poured between the beacons or joists, and a subfloor made of plywood, chipboard or ordinary boards is mounted above it.
  2. To protect the insulation from moisture, it is necessary to lay a waterproofing material underneath it.

To increase the density of filling granules, it is recommended to take different fractions of them and mix them before filling.

This is a very quick method of insulation that does not require much labor.

Video about the dry method of insulating a floor with expanded clay:

Wet laying of expanded clay

Here a screed is made from expanded clay concrete. Liquid concrete is mixed with expanded clay, after which it fills the space between the beacons.

In addition, the screed dries faster and cracks less. But the use of the wet method leads to the fact that the thermal conductivity of expanded clay that has collected moisture increases greatly.

Combined method

Insulation of a concrete floor with expanded clay under a screed is done as follows:

  1. Dry expanded clay is poured between the beacons.
  2. Then it is leveled.
  3. Its uppermost layer is watered with liquid cement mortar.
  4. When it dries, a regular screed is made on top.

The cement mortar forms a crust on the top layer of expanded clay and does not allow the lower layers to be deformed when pouring the screed.

If a large load is expected during the operation of the floor, then you can also supplement the structure with reinforcing mesh.

Insulation with expanded clay under a wooden floor on a concrete base

Materials and tools

To insulate a wooden floor with expanded clay, you will need:

  • jigsaw or hacksaw;
  • nail puller;
  • pencil;
  • roulette;
  • hammer;
  • building level;
  • electric drill;
  • shovel;
  • self-tapping screws;
  • damper tape;
  • coating material or film waterproofing;
  • sand.

This example examines the insulation of the first floor floor with expanded clay on a concrete base.

Dismantling the coating

  1. It is necessary to remove the floor boards and take them out of the room.
  2. Carefully inspect the logs and check their position with a level.
  3. Rotten logs need to be replaced, and new ones should be leveled.
  4. If the beams are in good condition, not deformed and have no deflections, then they can be left.
  5. If the damage is minor, it is enough to replace individual beams, but if they are rotten or loose, then you need to remove everything right down to the concrete.

Surface preparation

  1. Clear the base of the floor from debris, repair small cracks and inspect the corners - if there are deep cracks, they need to be filled with foam or covered with mortar.
  2. The joints around the perimeter of the walls and floor should also be filled with foam.
  3. Then you need to pour a layer of sand onto the base and compact it thoroughly, but if coating waterproofing is used, then there is no need for sand.

Waterproofing

  1. A special membrane or plastic film must be spread on the floor so that it covers the walls by 7-10 cm with its excess.
  2. The logs should also be under the film.

When the width of the canvas is not enough, you can lay several pieces overlapping and secure the joints between them with construction tape.

  1. Fix the waterproofing on the beams with a stapler, having first tucked it well in the recesses between the joists

  1. If coating waterproofing is used, the mixture must be applied to concrete that has been cleaned of dust, including sections of walls near the floor. With this option, the logs should be on top of the protective layer. It can be coated with liquid polymers, bitumen mastic, polymer-cement based mastics and bitumen-polymer mixtures. The composition should be applied in 2-3 layers at intervals of 3 hours, so such waterproofing will take a lot of time.

  1. Finally, you need to fix a damper tape at the height of the subfloor along the perimeter of the walls, which will resist cracking and deformation of the screed during temperature changes.

Installation of logs

  1. If the old logs had to be completely dismantled, then new ones must be installed. For this purpose, durable wooden beams or boards are suitable, which need to be cut to the length of the floor, then soaked in an antiseptic and completely dried.
  2. The wooden frame on the floor must be at least 10 cm high.
  3. The outermost joists should be located 2-3 centimeters from the walls, and the step between adjacent joists should be within 50-100 cm.
  4. All logs must be placed parallel to each other and at the same level, so that their upper surfaces all lie together on the same, strictly horizontal plane.
  5. The joists need to be secured to the floor using metal corners: screw one side of the corner with screws or self-tapping screws to the joist, and the other to the floor.
  6. The extreme corners should be 2-3 cm from the edges of the joists, and the step between adjacent corners should be within 50 cm.

Expanded clay backfill

Before forming a layer of expanded clay to insulate the floor, you need to mix its large and small fractions, and then pour it between the joists.

All that remains is to lay waterproofing on top and secure it with a stapler.

Flooring installation

A subfloor made of boards, chipboard or plywood must be attached to the beams protruding from the insulation layer, after which the finishing coating can be laid. The film sticking out near the walls can be cut with a knife and the gaps can be closed with decorative skirting boards.

Insulation with expanded clay under a wooden floor on the ground

Sometimes, instead of a concrete base, there is soil under the floor; in this case, it is necessary to insulate the floor with expanded clay over the soil in the following sequence:

  • Level and compact the soil.
  • Add about 10 cm of gravel.
  • Fill the gravel with sand and compact it tightly.
  • Next, add insulation, and the thickness of the expanded clay layer should be 15-25 cm.
  • Having leveled the insulation layer, it is necessary to fill it with concrete on top.
  • You can lay a wooden floor.

Insulation with expanded clay under a concrete base

Floor preparation

In this case, standard preparation of the subfloor is performed:

  1. It is necessary to dismantle the old coating, seal all the cracks, and clean the surface from dust.
  2. After this, lay a film on the base or cover it with liquid waterproofing. To cover all the joints along the perimeter of the floor, the film must be placed on the walls.
  3. Finally, at the level of the future screed, you need to secure the damper tape, after which you can proceed to insulation.

Expanded clay backfill

First you need to calculate how much expanded clay you need to insulate the floor. According to the standard for 1 sq. m area you need 0.01 cubic meters. m of expanded clay with a layer thickness of 1 cm. That is, the required amount depends on the thickness of the intended insulation layer and the area of ​​the room.

Expanded clay thickness for floor insulation:

  • On the 1st floor and above unheated rooms - 10 cm.
  • On the 2nd and above floors in residential premises - 3-4 cm.

For example:

  • In a room of 20 sq. m you need 10 cm of insulation thickness (expanded clay).
  • With a thickness of expanded clay of 10 cm, you need 0.1 cubic meters. m per 1 sq. m area.
  • For 20 sq. m of area will need 0.1 * 20 = 2 cubic meters. m of expanded clay (1 cubic meter of expanded clay = 400 kg).
  1. The resulting quantity must be prepared by mixing its different fractions.
  2. Then you need to fill the entire space between the beacons with this mixture, leveling the material with a piece of plywood or a rule.
  3. Particular care must be taken to fill joints and corners so that there are no voids left there.
  4. Then the expanded clay must be compacted carefully so as not to damage the granules.

Reinforcement

Place a large-mesh metal mesh on top of the insulation, which should be 4-5 cm away from the walls everywhere. The mesh should have no sharp protruding edges, bulges or dents.

Performing a screed

  1. The mixture for the screed should consist of 1 part cement and 3 parts sifted sand, which must be mixed well with water until an even thick consistency is obtained, then pour it in portions between the guides on the floor.
  2. The mixture must be leveled with a long rule, running it along the beacons and removing its excess.

    After this, you need to wait until the concrete gains sufficient strength to lay the floor.

This floor insulation with expanded clay assumes that the screed is laid directly on the insulation without additional insulation.

Video about floor insulation with expanded clay under a screed:

Expanded clay concrete screed

If the subfloor is very uneven or you need to significantly raise the floor level, then this requires an expanded clay concrete screed:

  1. At first, the surface also needs to be cleaned of dirt and dust.
  2. Then apply foam along the joints and cracks and apply waterproofing.
  3. Then you can begin the main process.
  4. Secure metal beacons to the floor using cement mortar.

  1. Having mixed cement and sifted sand in a ratio of 1:2, add 3-5 parts of expanded clay (this depends on the expected load on the floor) and 1 part of water.

  1. Fill the space between the beacons with the mixture 2-3 cm below their level.

  1. Compact and level the surface, to do this, drown the floating granules in the solution again.
  2. As soon as the screed has set slightly, prepare regular concrete without additives and pour it over the screed, then level it according to the beacons.

The screed should dry for 3-4 weeks. In the first days, its surface must be watered so that cracks do not form on it. The result is a warm and durable base that can last a long time. When the surface of the screed can be walked on, it should be covered with a hydrobarrier or film.

How did you insulate the floor with expanded clay, and why did you choose it? Write your answer in the comments - your experience is important to us.