Installation of screed on expanded clay: instructions for performing repair work. Floor screed with expanded clay: Pros and cons

The most common way of leveling floors is an expanded clay screed, which guarantees not only a perfectly flat surface, but also excellent heat-insulating and sound-proof characteristics. Affordable floor screed with expanded clay will minimize the financial costs of heating the premises in the winter season.

Thanks to the simple technology, the entire work process can be performed independently without the help of professionals. But, do not forget about some of the intricacies of the work. It is not enough just to pour cement mortar on expanded clay to obtain an excellent result.

What is expanded clay?

Expanded clay is a natural material that is widely used in the construction industry. It goes well with various ready-to-use mixtures and is used to create surfaces before installing decorative floor coverings.

Characteristics of expanded clay for screed:

Ease of use. As mentioned above, the entire workflow can be done by hand. But, to achieve best result it is important to adhere to certain technological rules. Otherwise, the screed will become unusable very quickly.
It reliably protects the room from extraneous noise, and is also an excellent heat insulator.
Does not collapse under the influence of sudden temperature changes.
The material is considered environmentally friendly.

In addition to the characteristics listed above, it should be noted that this material does not absorb moisture, has a high level of frost resistance, and is also resistant to heating.

Expanded clay granules are light enough and covered with a reliable outer shell. This casing is characterized by excellent resistance to the destructive effects of moisture. Due to the presence of cavities inside the granules, the floor is insulated with expanded clay under the screed.

Modern manufacturers care about their customers, so they offer them different options for filler. Today, three types of this material can be distinguished:

gravel - has an average granule size ranging from five millimeters to four centimeters. It is relatively lightweight and high level strength.
crushed stone - excellent for preparing concrete mortar.
expanded clay sand is a free-flowing material. The size of its granules does not reach five millimeters.

With regard to the screed, this term refers to the floor layer located under the decorative coating. When choosing the type of screed, you should pay attention to the general purpose of the room, as well as to the initial state of the base.

With the help of a neatly made screed, you can make your floor perfectly flat, and if necessary, warm, durable and strong.

It is worth noting that the floor screed device involves the use of a mixture of fractions. This approach has a positive effect on layer density. It is allowed to use absolutely any kind of expanded clay, but the most optimal is sand, which gives the least shrinkage during operation.

Of great interest is also expanded clay, the performance of which is quite high.

Advantages of expanded clay screed

Expanded clay floor screed is used not only to level it, but also to raise the level. At the same time, it strengthens and warms the surface. If we draw a comparative analogy, it can be noted that a floor screed with expanded clay has higher performance and quality indicators than a screed made of cement mortar.

Versatility. It can be used in various types of premises.
Ideally smoothes surfaces with large irregularities and cracks.
All types of expanded clay are not subject to decay processes and are resistant to fire.
Anyone can make a floor screed with expanded clay with their own hands.
High level of resistance to temperature extremes.
It can be used as an excellent insulation material with excellent performance.

Of course, in addition to the indisputable advantages, the expanded clay screed has some disadvantages. It is very important to carefully carry out all the necessary measures for the installation of the screed. Then a dry expanded clay screed will last for more than a dozen years, remaining reliable, durable and perfectly flat.

Adding expanded clay to the screed

Expanded clay is added to the mixture in the following cases:

If there is a need to raise the floor level. As a result, expanded clay for dry floor screed will be much cheaper and will have a high level of strength.
Due to its low weight, this material can be used for buildings with a weak foundation.
If indoors are used wooden floors who are not able to handle heavy weight.
If the floor slab is made of concrete or reinforced concrete slabs.
During the installation of infrared or electric underfloor heating.
If the priority is thermal insulation and soundproofing of the floor.
To minimize financial costs. The purchase of consumables will be quite cheap for buyers.
Due to the fact that expanded clay creates a layer with additional insulation, it is advisable to use it in the presence of communications located in the lower floor.

Installation of floor screed with expanded clay

Before starting work, you should prepare the surface and place beacons. Further, dry expanded clay of fine fraction is scattered over the entire area of the base. It must be evenly distributed over the surface so that the layer thickness is 20 - 25 millimeters.

Due to the presence of pits and the slope of the surface in different places, the expanded clay layer may not be the same. The main thing is that the device of the final surface becomes even. In order to determine how flat the surface is, you should use the building level.

Further, expanded clay is poured with cement "milk". As a result, the granules will adhere to each other. The resulting film will not allow moisture to escape in the future and the expanded clay pillow will not sag. In order for the resulting pillow to dry, it should be left in this state for a day.

As mentioned above, cement laitance may be needed during work. To prepare it, add several times more water than when creating a screed solution. It is worth noting that even experienced craftsmen, performing a floor screed with expanded clay, regulate the amount of water, guided by the course of the work process.

In conclusion, it must be said that a floor screed with expanded clay is the best option for creating a flat, durable and reliable surface. All components necessary for work are affordable. Anyone can purchase and use this floor material for its intended purpose, regardless of budget and skills. With a material such as expanded clay, the floor screed will last for many years without losing its original qualities.

The screed is the floor layer that precedes the floor covering.

From the purpose of the room, the state of the base, what material is chosen for covering the floor, determine the type of screed.

The screed evens out the surface under the floor, insulates the floor if necessary, makes sound insulation, and provides the design mark for the last layer of the floor.

A properly selected screed makes the floor strong and durable.

The screed has a height of 3 to 20 centimeters, so it is used when it is necessary to level the base under the floor with a height difference of more than four centimeters.

The same feature makes it possible, if necessary, to make or improve, arranging such a screed under the floor on the interfloor ceiling.

In no case should such a screed be used over a warm floor, as you know, and its use will lead to thermal insulation and the screed will simply not let heat through.

If the base under the floor has a mark much lower than the design mark, a screed with expanded clay makes it possible to raise the layer to the required height.

Apply this type of screed in front, parquet, tiles. Used indoors and outdoors.

Peculiarities

The popularity of using this type of screed is due to a number of positive properties of expanded clay - the main material of the layer:

Small specific gravity expanded clay on average 0.95 g / cm3 makes the screed lightweight. In cases where a thick underlying layer is required, a screed with expanded clay is indispensable.
The moisture content in the room is regulated, because expanded clay, having a natural origin, breathes in the composition of the screed.
It does not corrode: it does not burn, does not rot, and is not afraid of chemical attack.
The porosity of expanded clay gives the screed weak thermal conductivity and sound conductivity. Therefore, it insulates the floor and protects against noise.
Expanded clay has a heavy-duty shell and delegates strength and reliability to the screed.

For the screed, they take expanded clay of fractions from 5 to 20 millimeters. It is recommended to use two different grain sizes for better backfill density.

Device

Preparation of the base.

You will need: water level, building level, broom, scoop, trowel.

The old floor is being dismantled, if any. The base is cleaned of debris, concrete sagging. If there are holes, rusts, they are filled with cement-sand mortar. If there are communications on the floor, then they are wrapped in plastic wrap, securing with tape.

It is necessary to waterproof the base. There are several options for its implementation:

Hydroisol is applied using a blowtorch.
With a brush, coat the base and part of the wall in two layers with a waterproofing mastic to the height of the marks on the wall plus five centimeters. The second layer of mastic - three hours after the first.

Waterproofing can be done with plastic wrap, 2 mm or more thick. It is laid on the base and placed on the walls 10 centimeters above the level of the planned screed. The joints of the film are glued with wide tape.

We install beacons, we perform a screed

A very important question: How does the floor level fit in different rooms?

For example: the thickness of the layer of the laid parquet is 30 millimeters, the thickness of the tiles is on average 9 millimeters, which means that the height of the screed in the room where the tiles are to be laid should be 21 millimeters higher than in the room where the parquet is planned.

This is done in order to avoid sills and to make the floor at the same level in adjacent rooms.

Before backfilling expanded clay, the thickness of the layer is determined: from the base and two centimeters below the upper edge of the beacons, this difference will then be filled with a cement screed.

They fall asleep between the lighthouses of expanded clay, level them with the rule, focusing on a previously defined mark.

The surface of expanded clay is lightly tamped with a pusher or with feet, walking here and there, and spilled with “cement milk” - equal parts of cement and cement-sand mixture are diluted with a large volume of water to the consistency of milk.

Due to this, the surface of the expanded clay layer will become hard, and it will be possible to walk on it.

A day later, a screed is performed on the base obtained. The composition of the cement-sand mortar:

sand - 3 parts,
Portland cement 400 - 1 part.

The cement-sand mortar is poured to the upper edge of the lighthouses, leveled with the rule. The solution dries out for 14 days until it hardens completely:

In a day, when he grabs, the beacons are removed, traces of them and other irregularities are filled with cement-sand mortar and rubbed with a scraper.
After two weeks, the topcoat can be laid on the screed.

And the screed will be ready to carry full loads after 28 days.

Another way

Expanded clay screed, as in the previous case, has two layers.

The main difference is that the first layer does not consist of dry expanded clay, subsequently spilled with a low-cement mortar, but a mixture of expanded clay with a cement-sand mortar is immediately used, that is, expanded clay concrete.

Proportions of expanded clay concrete components:

8 parts of expanded clay,
3 parts of sand,
1 part cement.

This method is convenient in that it is possible to make expanded clay concrete right at the place of flooring, on any floor.

Expanded clay is poured into the container, so much water is poured to wet all the expanded clay. You will need a mixer for mixing.
Sand, cement is added, you can take the ready-made mixture.
Stir again.

The mixture is mixed correctly if it is thick, homogeneous and free of lumps. If the mixture is too dry, then not enough water has been added.

Spread the mixture between the lighthouses up to the calculated mark: we leave two centimeters for the second layer to the top of the lighthouse.

The second layer, an ordinary screed, as in the first method, is applied immediately to the first one without a technological break for drying. This is the advantage of the second method and its main feature.

Fill in the strip between the beacons:

the first layer - expanded clay concrete,
followed by the second - the screed, then the next strip between the beacons is filled in the same way, and so on.

It is important to align the second layer very carefully. Expanded clay screed will acquire the necessary strength, as in the first method after 28 days.

Practice tips: some nuances and possible mistakes.

The cement-sand screed (second layer) after the end of the work and until it dries completely, needs to be moistened with water to avoid cracks.

If, when preparing a cement-sand mortar, add liquid -, then moistening the surface of the screed during hardening is not needed.

A glass jar will help to establish whether the screed has gained strength, whether it has dried out enough:

Turn the jar over and place it with its neck on the surface of the screed, if the jar fogs up, it means that the screed is not ready for use, it has not yet dried out.

Neglect of exact adherence to the technological process for the manufacture of expanded clay screed, violation of the mode of technological breaks for the hardening of layers - can lead to irreversible consequences.

The device of a floor screed with expanded clay is a reliable base for any type of floor covering, it will improve the ecological climate in the house.

One of the main requirements for a home is a comfortable microclimate at any time of the year. It is quite difficult to achieve such an effect only with the help of a heating system, since without reliable thermal insulation, energy will be wasted. To save money and ensure comfortable living conditions, it is necessary to insulate the room. One of the most effective and inexpensive ways is to do-it-yourself floor screed with expanded clay.

This type of flooring has the following positive qualities:

When used in private houses on the ground, expanded clay allows you to raise the floor level to the required level, as well as protect the room from the cold that comes from the ground.
This option can be installed on top of reinforced concrete structures that cover unheated rooms, such as basement ceilings or starting floors on the ground.
Expanded clay can be used not only for insulation, but also for sound insulation.
Its relatively low cost allows it to be used for leveling surfaces with large differences.
The mass of the material is small, so it is easy to work with it, and ready-made structures do not exert significant pressure on the floors.
Under such a floor covering, you can disguise utilities, including the "warm floor" system, electrical wiring or piping.

Expanded clay is considered a unique and at the same time inexpensive material

Cons of screeds with expanded clay:

If the filling was carried out according to the so-called wet technology, then the thickness of the floor cake reaches 10 cm, which significantly affects the height of the room.
A dry screed with expanded clay is exposed to water, so if the liquid penetrates into the thickness of the material, you will have to remove part of the floor and replace the expanded clay.

What should be the thickness

In most cases, screeds with expanded clay are laid by the "wet" method using two technologies: first, a backfill layer is applied, and concrete is applied on top of it, or expanded clay is mixed with concrete and the floors are poured. In the first case, it is recommended to make a layer of material 3–7 cm thick, depending on the load and the degree of surface curvature. The concrete layer should be about 2 cm.If expanded clay is part of the wet mix, then a layer with a thickness of 5 to 10 cm is made.

With different arrangement schemes, the thickness of the expanded clay pillow changes

Expanded clay fraction

The material comes in three versions:

Small clay particles of various shapes, grain size 0.1–5 mm. The product lends itself to heat treatment.
Foamed clay gravel. It can have an oval or round shape, the size ranges from 0.5 to 4 cm.
Irregular crushed stone with sharp corners, which is made of clay, grain size no more than 4 cm.

The fraction of the material affects its main indicators

For dry screeds, it is recommended to use a fine-grained material. For wet, crushed stone or gravel is more suitable, while it is better to buy expanded clay different sizes... The fraction of the material is indicated on the package. Some manufacturers put expanded clay into one bag with grains from 20 to 40 mm.

Calculation of expanded clay

In order not to waste the budget for the purchase of material, you must first calculate the expanded clay for the screed.

With a layer thickness of 1 cm, 10 liters of expanded clay are required to finish one square meter of the surface.
If we are talking about a floor screed over an unheated room, then the thickness of the structure should be at least 10 cm. This means that for 1 sq. m you need 100 liters of material.
For standard rooms, 3-4 cm is enough, so the consumption of expanded clay will be 30-40 liters per square meter.

In practice, the material consumption is different. The fact is that most often the surface is curved, so more material is required for alignment.

The calculation of expanded clay largely depends on the method of arrangement and the type of screed

On a note! To purchase the correct quantity, it is recommended to start with 50 liters per square meter. interfloor overlap and 100 liters per 1 sq. m for screed on the ground or cold rough surface.

Pouring wet screed

In this case, the flooring cake consists of the following layers:

rough screed;
waterproofing;
damper tape;
expanded clay;
guide system;
finishing cement-sand screed.

General scheme for arranging a screed using expanded clay

Preparatory work

The first step is to carefully examine the base. If the old coating is in good condition: there are no large cracks, traces of corrosion, delamination, and so on, then you can simply remove dust and debris from it. Otherwise, remove the tie with a hammer drill and inspect again rough coating... Areas with oil spots must be sanded down to the base material, and all cracks must be repaired with a cement and sand repair compound. After the solution has dried, the surface must be treated with a deep penetration primer.

The old concrete base is necessarily carefully prepared

Definition of zero level

The easiest way to carry out this operation is using a laser level. It must be put on the floor and turned on, the cross-level must be directed to one of the walls. Then, opposite this wall, screw a self-tapping screw into the floor so that it rises by at least 10 cm.On the head of the self-tapping screw, you need to install something long and even, for example, a rule or a building level, at the intersection of the beam and the rule, put a mark on the tool. Then the same procedure should be repeated against another wall. If the mark on the rule is higher or lower than the beam, you need to adjust it by screwing in or unscrewing a self-tapping screw.

The laser level gives absolutely accurate results, but it is an expensive instrument

As a result, 15 self-tapping screws should be installed near each wall, all of them will be located at different distances from the floor. It is necessary to find the highest and lowest fasteners and calculate the difference in their heights - this will be the blockage of the floor. Beacons should be set taking into account the exposed fasteners.

On a note! If there is no laser level, you should not buy it for one-time use, you can purchase a hydro level. It is an ordinary tube that is filled with water.

It is also necessary to select the wall from which the beating will be carried out, and measure 1.5 m from the floor, it is easier to work at this height. Make a mark at this level, and then lean the tube against it so that the water level is opposite it. If one person is working, then fix the tube. If there are two, then one holds, and the second brings the opposite end to the other wall to a height of 1.5 m. If the water level is opposite the mark, then the floor is not overwhelmed. Otherwise, you must raise or lower the tube to get the water to the edge. Where this happened, you need to put an end.

So apply 4 points on each wall, find the highest and lowest, calculate the difference and subtract the resulting number from 1.5 m. Then measure down the resulting number of centimeters from the first point - this will be the zero level.

The accuracy that the hydraulic level gives is quite enough to break off the horizon of the finished floor.

Hydro and vapor barrier

As already mentioned, expanded clay is characterized by increased hygroscopicity, therefore it is important to protect its effects of moisture. If the floor is filled with expanded clay in a private house, then it is better to opt for roll waterproofing. It is recommended to lay roofing material or other similar material with a hot method, the strips should be laid with an overlap of 10 cm.

If the expanded clay concrete screed will be poured over a concrete base, then you can limit yourself to plastic wrap or coating waterproofing. At this stage, it is also important to lay all engineering communications, which should be hidden in a plastic corrugated box.

After that, it is necessary to glue the lower part of walls, stairs and other structural elements with a damper tape, which will protect the surfaces from cracking due to linear vibrations of the screed. The tape has an adhesive surface and is easy to install.

Polyethylene film is considered the cheapest option for waterproofing, but it is undesirable to lay it under a wet screed

First fill option

Second way

In this case, it is necessary to prepare two types of solution. One consists of cement, sand and expanded clay in proportions 1: 2: 3. First, water is poured into the concrete mixer, then expanded clay is added so that it has time to absorb a sufficient amount of moisture, after which cement and sand are poured. The second solution is an ordinary cement-sand mixture with water.

First, lay the composition with expanded clay, its layer should be about 1/4 of the total thickness of the cake. After leveling, pour in the usual solution and repeat the sequence again. As a result, a coating of 4 layers is obtained, the top is the finishing concrete screed. Expanded clay screed in this case is a little colder, but this way you can save a little time.

The presence of a finishing cement-sand screed gives a perfectly even coating

Third method

Here a screed with expanded clay consists of one type of solution: a mixture of expanded clay, sand and cement, to which water is added. It is important to remember that expanded clay is much lighter than water, therefore, in a solution it will always tend upward and it will not be possible to perfectly align the coating.

Mechanical strength of expanded clay concrete with wet mix leaves much to be desired

The composition is simply poured between the lighthouses, leveled as much as possible by the rule and left to dry. Such a screed requires further processing. The fact is that expanded clay is a rather fragile material, so it will gradually collapse and become very dusty. To avoid these troubles, it is recommended to apply a topcoat with self-leveling compound or ceramic tiles.

Dry screed

This is a relatively new technology that does not involve the use of water in a mixture, so the work is easier and faster. In this case, the floor cake consists of the following layers:

base;
waterproofing;
damper tape;
backfill based on expanded clay;
gypsum fiber boards.

The dry screed is an order of magnitude warmer than the wet version, in addition, it is easier to equip it

Installation technology

Before making a screed, it is necessary to carry out the same preparatory work as when filling. It is only important to take into account that the surface under the screed should be as flat as possible in order to prevent the material from sagging.

So, the algorithm is as follows:

After waterproofing, you need to glue the damper tape. Usually this product is equipped with an adhesive layer, but if it is not there, you can press it down with expanded clay slides.
Along one of the walls, it is necessary to pour a shaft of expanded clay for dry floor screed, on which the lighthouse is laid. Its height is controlled by adding or removing material. At this stage, it is also important to consider that about 2 cm of the thickness of the cake will be covered with wood-based panels.
Then you need to retreat from the shaft a distance 20-30 cm less than the length of the rule. Thus, apply the material over the entire area and install the beacons on top. At the end, you should check everything with a building level.
Expanded clay is poured onto the area between the two lighthouses and leveled with a rule. After that, the lighthouses are carefully removed from the surface and fill the formed grooves. Then you can start installing the topcoat.

With a strong desire, the complete arrangement of a dry expanded clay screed can be completed in 1 - 2 days

Installation must start from the far corner of the room. It is necessary to cut off the part with the lock on one side, grease the lamellas with PVA glue and lay the next sheet, fixing with locks. It is important to remember that expanded clay should not get at the joints of the sheets. If this happens, you should sweep it away. As you progress, the sheets must be cut so that they fit snugly against the wall.

After laying two rows, the elements are fastened with self-tapping screws, which are screwed into the joint. The step of the fasteners is 15–20 cm, so the entire floor area is filled. It must be borne in mind that you should not make joints in the area interior doors, it is better to take them out 20 cm further.

A dry screed is the best suited for installation in city apartments, since with a small thickness it has good thermal insulation data

After the glue has dried, remove the surface with a vacuum cleaner, cut off the polyethylene and the damper tape, and you can proceed to further finishing work.

Even a novice home craftsman can equip a warm screed with expanded clay. The main thing is to choose the right materials. If there is no experience in the manufacture of mortars, it is recommended to purchase ready-made building mixtures.

Often the surface of the floor has large differences, especially in recently commissioned objects. The steps between the floor slabs can reach a height of up to 10 cm. Leveling such floors with concrete is ineffective for two reasons:

Economically disadvantageous - high material consumption
The screed turns out to be very massive and dooms the floor slabs to unnecessary stress

To facilitate the entire structure, ingredients with a low density are added to the screed; often expanded clay acts in their role. This material, depending on the size of the granules, has a thermal conductivity coefficient of 0.07 to 0.16 W / m. Knowing how to properly screed on expanded clay, you can arrange a warm floor with good thermal insulation properties.

Experts recommend using expanded clay for leveling the floor with level differences over 5 cm.Using this material for screed, it should be borne in mind that its granules have low density and often float to the surface of the solution. It is difficult to determine empirically what layer the screed is poured onto the expanded clay so that it evens out all the irregularities and does not crack. It is more rational to listen to the advice of experts and make concrete in a layer of 2-3 cm.In this case, the technology of performing work on the device of a flat floor is divided into stages:

Bringing out a single horizon line throughout the apartment.
Light fraction flooring.
Installation of beacons.
Leveling fill.

Let's consider each operation in more detail.

A flat floor throughout the apartment without differences between rooms looks beautiful. It is better to mount it all at once in all rooms, and not separately - first one, then after a month or two, the next. To obtain the same floor level in the apartment, the zero horizon line is beaten off all walls.

It is more convenient to mark with the help of a water building level. It will allow you to project a given mark on all walls with an accuracy of 1 mm. Marking with this tool is carried out as follows:

Having stepped back from the floor surface 1-1.5 m in any of the rooms, make a mark on the wall
The first communicating vessel with divisions is fixed near the drawn risks, moving along the walls, the second level of the horizontal is marked every 50-60 cm
The so-called "zero level" is drawn along the marks with an even ruler.
Having departed from the highest point of the floor 7 mm (2 mm for concrete + 5 for expanded clay), the risk of finishing pouring is marked on the wall
The screed mark is projected onto all walls and a continuous line is drawn, which will be orienting for the installation of beacons

After breaking off the horizontal, they begin to prepare the surface. The floor is cleared of construction debris and dust, then sheets of waterproofing material are spread over the entire area with an overlap on the walls to the marked horizontal. You can use plastic wrap as protection against moisture. The joints between the canvases are overlapped with an overlap of at least 10 cm and glued with moisture-resistant construction tape. Expanded clay is laid on top of the film.

Light layer installation

The material that facilitates the screed is usually classified according to the size and shape of the fractions into the following groups:

Crushed stone. Expanded clay grains of this type are 5-40 mm in size, predominantly angular in shape. They are obtained by crushing large pieces of fired foamed clay.
Expanded clay gravel. This material is rounded brown granules. According to GOST, gravel is divided into fractions of 5-10, 10-20 and 20-40 mm in size. It is used as a heat-insulating material to facilitate the construction of the screed.
Expanded clay sand. It is obtained by crushing fired clay granules to particles less than 5 mm in size. Sand is used for the construction of light thin screeds.

Expanded clay is mounted in a screed in two ways - by pouring a dry fraction followed by pouring "cement milk" or spreading the solution. The granules have a low density and, if they are not fixed, they will float through the top layer and form irregularities on the surface of the screed. The most reliable fixing of expanded clay in a single mass occurs when mixing the solution.

To prepare the mixture, take 1 part of cement grade M-500, 2 shares of building sand and 7 - expanded clay gravel... The finished solution is spread on the floor, making a layer 2.5-3 cm below the drawn horizon line and leveled with the rule. As soon as the expanded clay concrete gains the initial hardness at which you can walk on it, they begin to install the beacons.

Securing guides

Construction beacons are used to control the even fill layer. They are located at a distance less than the length of the rule by 10-15 cm from each other. The initial guide is mounted, stepping back from the wall 25-35 cm. To fix the beacons, self-tapping screws are used, which are screwed into expanded clay concrete. The use of screws allows you to smoothly adjust the height of the bar.

Self-tapping screws are screwed in so that the top point of the beacon is flush with the marked horizon line. The screws are placed along the entire length of the plank with a distance of 35-55 cm. The even position of the guides relative to each other is controlled using a building level 2 m long.

An alternative option is to install cushions made of a cement-sand mixture under the beacons. With this method, the position of the slats is adjusted by pushing them in or out of the pillows. After fixing the beacons, all residues of the solution that are above the guides are carefully removed. Then they wait for the mixture to harden, check the reliability of the fixing of the strips and proceed to pouring.

Surface leveling

The final layer of concrete mixture (1 share of cement grade M-500 for 4 parts of building sand) is poured between the beacons. When manually mixing the solution, first mix the dry fractions until a uniform gray color and then add water. When using a concrete mixer that lightens labor costs, 1 part of water, 1 cement, 4 parts of sand are poured into the container and wait until mixing into a homogeneous mass. Experts recommend adding plasticizers to the composition, for example, PVA glue. These substances increase the adhesion of the mortar and prevent cracking of the concrete.

A less labor-intensive, but more expensive method is the screed device using ready-made dry mixes. In addition to plasticizers, they include special components that provide the screed with a long service life. Such mixtures should be diluted, strictly following the recommendations of the manufacturers.

The solution prepared by one method or another is laid out on expanded clay concrete and leveled using a rule that is carried out longitudinally to the beacons in close contact with their upper surface. To make the concrete lay down evenly, it is distributed by vibration movements of small amplitude transversely to the guides. If pits appear, the mortar is taken from the leading edge with a trowel and placed in the defective place.

To make the screed monolithic, experts recommend arranging it in one day. If it is impossible to fill the floor at once in the whole apartment, it is leveled in the rooms, insulating it with a strip 3-4 mm thick, thereby providing a thermal compensation seam.

After 4-5 hours, the concrete hardens and the beacons can be removed, and the resulting voids can be sealed with mortar. To prevent the screed from cracking, it is recommended to spill it with water from a watering can 1-2 times a day for a week.

Expanded clay lightens the concrete and allows you to make a screed up to 15 cm thick. So if the floors are frightening with drops, you should not stumble over them. Effective remedy to eliminate such defects - a screed in two layers with expanded clay, the installation of which gives the room a completely different look.

Complete replacement of floors in a private house or apartment is rarely performed. In this regard, the repair should initially be approached competently. This will help to fulfill it unmistakably, and the dream of flat floors, characterized by strength and durability, thanks to the pouring of the floor with expanded clay, it is easy to carry out. Such a screed is considered the simplest, but very effective option for leveling floors under any modern coating.

To begin with, you should know that the distinctive qualities of expanded clay are lightness, porosity, environmental friendliness. It is made of baked clay, very durable and has excellent sound insulation properties. Another plus is low thermal conductivity.

Expanded clay concrete is superior to other types of screed in many respects:

the level of noise absorption;
mass;
thermal insulation properties;
breathability;
durability;
ease of transportation;
expanded clay is suitable for any floor covering.

In order to make the most of all these qualities, it is important to carry out the entire process of pouring the floor with expanded clay correctly and in stages.

What will be required when working?

To begin with, the entire surface must be cleared to the slab.

All skirting boards are dismantled, debris is removed, all existing holes and slots are cleaned as much as possible. If there are any necessary wires on the floor, then care should be taken to protect against moisture penetration. Sometimes polyethylene is enough, with which the wire is wrapped and then secured with tape. For greater reliability, a cut corrugation is also put on.

Waterproofing is an important step before pouring a floor

Before starting the main work, you should take care of waterproofing. It is especially important if the dwelling is not on the ground floor. In order to avoid leakage to neighbors living on the lower floors, a simple mixture for plaster is taken and all holes and holes are sealed with it. that is, everything that can lead to the penetration of liquid downward.

Now - about the waterproofing of the floor itself. There are several ways, however, the most common and cheapest is the use of hydrosol (liquid mastic).

Bitumen-polymer mastic

The mastic is applied with a brush to the floor and wall. The part of the wall that is just above the border of the future floor screed is being processed. Hydrosol is applied in two layers with an interval of 3 hours. No desire to spend money on liquid mastic? In this case, you can spread plastic wrap on the floor.

In this case, several points are also taken into account:

the film must be thick;
overlap (40-50 cm), fastened with tape at the seams;
the edges of the polyethylene are wound 10 cm onto the walls above the future border of the screed.

If the waterproofing is completed, then it is time to move on to further steps to fill the floor with expanded clay, namely, to the setting of beacons.

How are lighthouses displayed?

The highest point is chosen as a reference point. The "main" beacon is placed on it, at least 6 mm high. Others should be equated with him. They are fixed with cement mortar or alabaster. If only they stood securely. In this case, everything should be done quickly enough.

Using a level of any kind, the intended edge of the screed is marked on the walls. Lines are drawn along the marks, usually a dye thread is used. Connection of lines is important! The entire base-floor is divided by lighthouses into parts 1 m wide with a reference point on the line. It is easy on them to level out the expanded clay layer in the future.

When marking, take into account the height of the finishing coating in other rooms. This is necessary to avoid unnecessary sills. You should also consider the presence of wires, podiums, etc. For a more reliable installation of lighthouses, expanded clay can be spilled with a mixture. From two bags (50 kg) per 1 m2, a layer of 4 cm is obtained.

Video - How beacons are displayed

The easiest way to screed a floor with expanded clay

There are many known methods for arranging a screed. Let's consider the simplest, but time-consuming. It is within the power of even one person who is not very knowledgeable in construction. After the surface is ready, it is covered with dry expanded clay.

What should be the fill thickness? At the top point - 5 - 6 cm. Laying expanded clay, depending on this. Its consumption will be different in different areas, its evenness as a whole is important. This is facilitated by inscribed lines and installed beacons.

At the same time, we must not forget about the level.

What are the proportions? There is no exact recipe. In order to find the appropriate solution, the usual mixture is made, but 3 times more water is added. A small area is filled with this liquid. A mixture is considered normal that does not remain on the surface and does not seep through the granules without a trace. The solution is made "by eye". The main thing is that when it is applied, water does not leak. The resulting film should become a kind of expanded clay insulation. The fill dries about 24 hours.

The final stage includes the final filling with the prepared solution.

Ready. Let it dry. It will be possible to walk in a couple of days. It will take about a month to completely dry, periodically it is necessary to spray the surface with water.

Two-layer screed - method number 2

In this way, the screed is formed in two layers. The procedure, despite the seeming complexity, is quite simple and does not take much time.

How is the work done?

If it is found that bubbles, pits and dips appear, then they must be filled with a solution. Tighten with a rule until complete leveling. As in the first case, the surface will be ready in a month, give or take a few days. To retain moisture, you can cover it with a polyethylene film for the duration of drying.

expanded clay

When do you need a floor screed with expanded clay

There are situations when pouring a floor with expanded clay is the only right solution.

The height of the flooded space is from 10 cm and above.
Weak hardwood floors.
Savings on cement and expensive mixtures are required.
The presence of a heating system in the floor.

In the first case, this is due to the fact that if the screed is made only from cement or only from a mixture, it will be very heavy, which can negatively affect the floor slabs.

In the second, there is a clear need to lighten the entire structure. In the latter case, safety plays an important role.

A correctly executed screed makes it possible long time do not think about repairing floors. Substrate irregularities are easily eliminated, and the topcoat receives a strong, durable support. Any warm floor is great on such a basis, the motto of which can rightfully become the words "cheap", "high quality", "fast"!