Cementing of floors, methods of implementation and materials. Self-leveling floor or screed, which is better: what is the difference between a cement screed and a self-leveling floor Do-it-yourself cement self-leveling floor

If there is a slight difference in the floor, approximately from 2 mm to 2 cm, it is more advisable to use a self-leveling floor to level the base. The polymer mixture dries faster than regular screed and is much easier to work with. You can see this for yourself by carefully reading the step-by-step instructions for working with self-leveling floors, saving time and effort when working with long-drying cement-sand and concrete screeds.

The self-leveling floor is a self-leveling polymer mixture based on cement or gypsum, which allows you to completely prepare the floor for the next stage of work. Depending on the final goal, the self-leveling floor can act as a flat base for further finishing (tiles, parquet, laminate, etc.) and finishing. It is quite rare to find a self-leveling floor in its pure form in an apartment, since the thermal insulation and aesthetic qualities of such a floor are not very high. Although the variety of colorful colors of modern mixtures helps solve the aesthetic problem, more often the self-leveling floor in its pure form is found in production workshops and large retail areas. But pouring a self-leveling floor at home with a 3D effect will look very impressive.

Self-leveling mixture allows you to achieve high-quality results with minimal effort

Compared to screeds, self-leveling flooring has greater wear resistance. It is possible to lay the floor covering on a hardened floor only after 7–10 days. This time is specially allocated to ensure that all the particles of the binder materials are connected to each other, the coating is completely hardened, and you can safely work with the finishing. As for the hardening of the self-leveling mixture, it occurs 4–6 hours after pouring. At the end of this time, you can safely walk on the floor in soft shoes. That is why it is important to work quickly with the mixture so that each subsequent portion of the fill has time to join with the previous one and form a monolithic coating of the same level.

Gypsum self-leveling mixtures are warmer than concrete and are ideal for laying under parquet. Such finishing and self-leveling floors equally absorb excess moist air and release it back. The self-leveling floor can withstand high loads - about 800 kg per 1 cm 2. Other advantages of using this leveling technology include the ease of working with the mixture, the formation of a durable monolithic and seamless coating, and the waterproofing properties of the material. After hardening, the self-leveling floor can withstand a wide range of temperatures equally well. Therefore, it can be poured both in wet warehouses and in saunas with dry and hot air. The only drawback of this floor leveling method is the high price, but it pays for itself if you look closely at all the advantages.

Screed and self-leveling floors have one similar feature - both mixtures are intended for leveling the floor for further finishing. However, this is where their similarities end. Different degrees of granularity of materials affect the technology of pouring mixtures, preparatory work and the characteristics of the finished coating. So, if a cement screed needs to be leveled manually, then with a self-leveling floor everything is different. It is not for nothing that it is also called a self-leveling mixture. Polymer binders and a less viscous consistency allow the material to spread over the surface and fill all cavities on its own. The composition also affects the hardening time and quality characteristics of the coating. It will take at least a day for the screed to polymerize before you can walk on it, while the self-leveling floor will take only 4 hours. Complete drying of the screed may take a month or more. Prolonged drying and slow evaporation of moisture leads to differences in height in different parts of the floor.

The small grain size of the filling mixture indicates its use at the final stage of floor installation.

Pouring a self-leveling floor allows you to avoid all these problems. However, for good adhesion of the material to the base, it must be carefully prepared (sanded, removed oil traces, coated with a primer), which is absolutely not required for a screed. You will also need to constantly maintain room temperature in the room, and quickly work with the prepared working mixture. The consumption of self-leveling floor per square meter is less than concrete and cement screed.

Before pouring a self-leveling floor with your own hands, you need to carefully prepare the surface, get rid of all irregularities and traces of paint and solutions. To do this, you can use the manual method - a hammer and a spatula. However, for more efficient work, we recommend using a vibratory grinder or a regular grinder. When working on large areas, we use larger equipment to grind the surface - a mosaic grinder. Lumps and irregularities will create unnecessary problems and differences in the foundation, so you must definitely get rid of them. Just like against chips and cracks on the surface. If there are any, we seal them with putty. To reduce the hassle of removing oil stains, paint and all kinds of solutions, we recommend that you fill the floor before painting begins. In addition to cracks on the base of the floor, do not forget about the seams near the wall. They also need to be cleaned and sealed with putty or foamed so that the mixture does not leak through the cracks.

The mixture will be perfectly absorbed into the primed surface and the risk of peeling will be minimized.

When the initial preparation of the base is completed, let the putty dry and move on to the next stage - priming the floor. This point is mandatory. It not only improves the adhesion of the material to the floor, but also prevents excessive absorption of moisture from the self-leveling floor into the base. The mixture spreads better on a primed surface. To prime the floor, it is preferable to use a deep penetration primer rather than concrete contact. The presence of quartz sand in it gives the surface roughness, which is why the self-leveling floor can spread unevenly. We need to achieve a smooth surface. We don't skimp on the primer. The more evenly and thickly it is applied, the better the final result will be. Ideally, we recommend going through the primer 2 times. Now we wait for the primer to dry.

Another point that needs to be taken into account at the preparatory stage of work is the installation of damper or edge tape. It is mounted below along the entire perimeter of the junction of the floor and the wall and does not allow the poured floor to expand while gaining strength. However, if the thickness of the tape leveling layer is a couple of millimeters, the installation of the damper tape can be neglected. In all other cases, when the thickness of the leveling is 1 cm or more, installation of a damper tape is required.

To determine the thickness of the pouring layer of the self-leveling floor, it is necessary to find the zero level. It is more convenient and faster to carry out this procedure using a laser level. It is installed in the middle of the room and taps a straight line along the entire perimeter of the room for further measurements. Unfortunately, not everyone has a laser level, so as an alternative we use a regular level and a pencil. At any height from the floor, for example 1 m, using a pencil and level we draw a line along the entire perimeter of the room. For ease of work, you can use a beating thread. Using a tape measure, we find the zero mark, the highest point of the subfloor. This will be our difference, by which we need to raise the entire floor in order to level it.

We achieve maximum measurement accuracy using laser technology

If there are more significant differences in the middle of the base, increase the thickness of the layer to ensure that all the unevenness of the floor is leveled into one plane. We mark the thickness of the zero floor at the bottom of the wall on the damper tape. We transfer the resulting size to various points on the walls. Connect the marks into a single line. Depending on the thickness of the layer, we select the appropriate quick-hardening mixture for the tile or other floor covering. The minimum and maximum thickness of the floor leveling is indicated on the packaging. We purchase the required number of packages, focusing on the layer thickness and material consumption specified by the manufacturer of the self-leveling floor.

Mix the mixture strictly according to the instructions. Otherwise it will lead to loss of strength. It is especially important to add as much water as indicated on the package. Some beginners and even experienced craftsmen neglect this rule and add more liquid than required. What does this lead to? Excess water does not allow achieving a uniform structure. When pouring the floor, nothing is noticeable, but after hardening the first flaws are visible. This is due to the fact that excess water remains on the surface and the dispersion sags.

The texture of the flooring mixture should be smooth and uniform.

The temperature of preparing and pouring the mixture is another important point that affects the strength gain and quality of work. The manufacturer also indicates these temperature limits on the packaging. The optimal parameters are considered to be room temperature in the range of 18–25°C. Low temperatures, below 5°C, will lead to the destruction of polymers and loss of strength, the water will begin to solidify, and the mixture will not harden. High temperature, over 30°C, promotes rapid evaporation of water, which prevents the mixture from spreading

Before pouring, the mixture must first steep for 3–5 minutes. This is important, otherwise unevenness may form on the surface. The recommended period for using the working mixture after preparation is also indicated by the manufacturer. As a rule, it ranges from 40 minutes to 1 hour. We recommend pre-preparing several containers with the working mixture. While we are pouring the first portion, the rest will already ripen. After settling, mix the mixture again with a construction mixer.

In order not to be afraid of stepping and leaving marks on the fresh filling field, we put paint shoes (boots with spikes) on our feet. These shoes will allow you to walk comfortably on fresh floors and trim undisclosed areas if necessary.

Now we recommend dividing the room into several zones. To prevent the self-leveling floor from extending beyond the boundaries of the room, we block the threshold with a metal profile, fixing it to the floor. Take the first container and distribute the mixture evenly. Although the self-leveling floor is considered self-leveling, you should not pour it into one point and wait until it spreads over the surface. After pouring and spreading the mixture, connect the needle roller. It helps the mixture spread and expel air bubbles. During leveling, we adhere to the level height marked on the damper tape. After pouring, it should completely cover the line around the perimeter. If the difference is only a few millimeters and you did not install a damper tape, level the self-leveling floor evenly with a needle roller towards you. We do this until the end of the room. We pour the mixture from the window and gradually move towards the door.

Let the floor dry and harden. The next day we check the quality of work using a level and a rule. If everything is smooth, there are no cracks, you can be congratulated on a successful job. Now we wait 7-10 days for the floor to finally set and settle, and then we begin laying tiles, parquet or other flooring.

Installing a self-leveling floor only at first glance does not seem to be a very complicated procedure. However, a frivolous attitude to the filling process threatens the appearance of significant defects - cracks, peeling and excess air bubbles in the new coating. These problems can be avoided by following certain installation rules, and then the finished floor will delight you for many years.

What mixtures are best to use?

Construction stores offer a huge selection of self-leveling floors, so you need to immediately decide what kind of floors you want. Budget options are usually used as a base for other floor coverings. Decorative self-leveling floors will cost much more.

The types of ready-made mixtures offered have their own characteristics and vary significantly in price. It takes some effort to choose the best option among such a variety.

To calculate the required amount of dry mixture, you need to multiply the height of the future floor by its area. It is also necessary to carefully read the instructions for the selected mixture - it may contain information about the need for special tools or additional processing of the base.

Preliminary work

• construction mixer;
• electric drill;
• rollers and spatulas;
• special shoes that allow you to move on the floor without damaging the surface.

From building materials, prepare the mixture for the self-leveling floor, a primer and a suitable container for diluting the mixture.

The need for additional operations before installing a self-leveling floor is determined by the distance between the concrete base and the expected level of coverage. Usually the floor height is the same as in the adjacent rooms.

In this case, the coating should not interfere with opening and closing the doors. If the distance from the base to the future floor is more than 4 cm, then it is better to first fill the screed, and then install a self-leveling coating up to 1.5 cm high. Otherwise, the repair will cost a pretty penny.

Preparing the base

Before priming the base, it is necessary to carefully putty all uneven areas, cracks and chips. After the putty has dried, a primer can be applied. The number of layers will depend on how quickly the base absorbs the composition. If the primer is completely absorbed, then you need to apply more, remembering to dry each layer. The result should be a flat base that does not allow moisture, vapors and gases to pass through.

The level of future flooring is marked on the walls, taking into account the height of the floors in adjacent rooms. Don't forget about the door - it should open and close freely. For extra strength of the screed, a reinforcing mesh is laid on the base of the floor.

Preparation of the solution

According to the instructions, the dry mixture is diluted with water and mixed with a construction mixer. Some mixtures are stirred at certain intervals, others are diluted in the usual way.

Only strict adherence to the instructions guarantees the quality of the self-leveling floor, and vice versa, deviation from the manufacturer’s instructions often leads to undesirable consequences. For example, an excess of liquid reduces the strength of the coating, and a lack of it leads to a loss of plasticity of the mixture.

To make the solution homogeneous, first pour in water, and then pour the mixture into it. The cleanliness of the container plays an important role here. If you don’t have a construction mixer, you can mix the composition using an electric drill with a special attachment.

The resulting mixture is used immediately after preparation, following the instructions on the package. It is important to meet the time specified by the manufacturer, since the thickened solution can no longer be diluted with water without losing the strength of the coating.

Self-leveling floor pouring technology

The prepared mixture is gradually poured onto the concrete base, starting from the recesses (if any). The mixture is then spread with a notched trowel and leveled with a notched roller.

After pouring, the coating must be compacted, removing air from it. For this procedure, special shoes are used - “crampons”. You can use the new floor only after it has completely dried (the time is determined according to the instructions).

Common Mistakes

• The self-leveling floor is called self-leveling because the plastic mixture spreads, forming a perfectly flat surface. But sometimes the mixture needs help. When the spilled solution does not reach the corner, it is stretched there using a notched trowel.
• An incorrectly selected roller may move the mixture too intensively, or not move it at all. The needles of the “correct” roller should be 1-2 mm higher than the filling level.
• It is better to provide dampers in advance and take into account the height of the threshold, even if it seems that the threshold is high enough and is capable of containing the spilled mixture in the room. However, the slope of a room can be deceptive. In any case, the installed dampers will not interfere, but they will eliminate the need to urgently look for suitable materials to create a barrier in the path of the flowing mixture.
• Don’t save time and make a preliminary measurement of the heights of the room. There are cases when some irregularities are not visible to the eye before pouring the mixture. And after the work is completed, a protruding bump will ruin the entire repair and require additional expenses.

Despite some features and nuances, screeding a floor with a self-leveling ready-made mixture is a fairly simple and very interesting process that does not require professional skills and provides an excellent result.

How to fill a self-leveling floor yourself

Many of us are a bit of a perfectionist. We want everything to meet certain standards. This also applies to home renovations, and in particular to floors, which will be a key element in this article. There are a huge number of flooring materials. Each of them has its own advantages and disadvantages. However, the self-leveling floor is especially different from the rest. Its main advantages are that it perfectly levels the surface. It is also suitable as a topcoat. This floor can be made in any color or even have a complex pattern. And the main design novelty is 3D floors.

Everything is clear with the design. There is no limit to colors and designs. So let's get straight to the point and find out how to fill a self-leveling floor with your own hands.

Beginning of work

All construction work begins with preparation, and the application of a poured floor is no exception. The first step is to inspect the surface for any significant differences in height. If there are any, you should deal with them using a jackhammer.

Done? Great. We move on, but the inspection is not over yet. Now we are looking for cracks. And if even a small gap is found, it should be sealed with special dry mixtures. You can also make a new concrete screed, which is then treated with a primer and other special means. This will give the coating additional strength.

At the same time, do not forget that with changes in temperature and humidity, the screed may become deformed. To minimize this effect, foam deformation tape should be glued around the entire perimeter of the room. At the end, when the self-leveling floor is dry, this tape will need to be cut off. And seal the formed cracks with sealant.

Conditions for pouring

When pouring the floor, certain conditions must be adhered to. First of all, this concerns temperature. The readings on the thermometer should not fall below +15 degrees. If the temperature is lower, the material consumption increases significantly. However, high temperatures also have a negative effect. They speed up the hardening process, so you will have less time to work.

All windows and doors in the room should be closed so that there is no draft in the room. However, that's not all. The moisture level of the concrete base should not exceed 4%. If the indicator deviates upward, the surface should be treated with a second layer of waterproofing.

Does everyone know the role of primer? If not, read the next sentence. A primer for cement or concrete bases is designed to increase adhesion. If you are using a cement-sand screed, a regular primer will do just fine. But with a concrete base, it will no longer “roll”; you will need to buy a special primer. It can be applied using a roller and brush (in hard-to-reach places). If the screed is too porous and dry, the procedure should be repeated. But only after the first layer has completely dried.

But now a very useful feature will be “burned”. The fact is that you can do without most of the procedures described above. No, this does not mean that you can pour polymer floors onto an unprepared base with cracks, holes and bumps. No way! However, you can use a self-leveling concrete screed. After drying, the floor will be perfectly smooth. Another advantage of such a base leveling system is that the floor practically ceases to absorb moisture. In the case of self-leveling floors, this is especially beneficial. But you still need to treat it with a primer.

Necessary materials

You should approach pouring a self-leveling floor fully prepared. A couple of brushes are not enough here, but there is no need to be alarmed, since the set is quite standard. So, you will need:

• Wide spatula. It will be required for the preliminary distribution of the total poured mass.
• A needle roller that will remove any air bubbles that appear.
• Construction mixer for mixing the mixture.
• Materials for preliminary repairs.

Also, do not forget about the special sole that is attached to the shoe. It is made in the form of high spikes. Thanks to it, there are no footprints left on the floor, and you don’t have to throw away your shoes.

Carrying out basic work

So, your floor is perfectly level and your tools are neatly stacked and ready for use? Great! Let's get to work. You are unlikely to be able to find a self-leveling floor from two different manufacturers with an absolutely identical composition. Therefore, it makes no sense to give universal advice on mixing components. Therefore, first you should carefully read the instructions attached to the product, so as not to spoil everything at the very beginning.

When the mixture is successfully prepared, pour it onto the floor. But only without sudden movements. If liquid gets on the wallpaper, the wall covering will have to be replaced along with the floor. It is easier to remove marks from tiles, but also very problematic. Therefore, we do everything calmly.

Next, using a spatula, the mixture should be evenly distributed throughout the room. By the way, the future floor should be poured near the far wall from the door. Also, don't forget about studded tips for your boots. If this is your first time dealing with such an experience in renovating premises, it is better to take a notched trowel. With its help, you can distribute the composition more evenly.

Distributed? Do you see any air bubbles? So, they shouldn't exist. To get rid of them, you need to walk around the room with a needle roller.

The floor is almost ready. Now you just have to wait for it to dry. Usually you can walk on it in regular shoes within a day. However, there is no need to rush into arranging furniture. The coating will be able to fully withstand serious loads only after 3 days. But it is worth considering that these terms are conditional. As already mentioned, the composition of the material is always different. And not only the mixing method, but also the hardening time depends on this.

How to make 3D floors

If plain versions of self-leveling floors do not suit you, make them in 3D format. Of course, this option will add originality and uniqueness to the design of the room. However, it is worth stocking up on strength, because the installation process is more painstaking. If you are not afraid of difficulties, read on.

To make a 3D floor you need to do the same manipulations as when applying conventional material. That is, pour out the liquid, distribute it around the room, remove air bubbles and wait until it dries completely. However, this is only part of the job.

Next, you will need a special large-format print that will be glued to the floor. The procedure is somewhat reminiscent of wallpapering, since it is important that in the end there are not a single wrinkle or air pocket left. Instead of printing, you can also use various objects, such as coins.

Now the last step remains - applying varnish. It will extend the life of the floor and protect the design from erasing. And if any decorative elements are used, the varnish will securely fix them.

Regardless of what kind of floors you make, 3D or regular, the result will be beautiful. However, if the entire process described seems complicated to you, use the services of a specialist.

Video: self-leveling floor - secrets of mastery

Step-by-step technology for pouring self-leveling floors

The technology of pouring self-leveling floors compares favorably with concreting screeds in its high productivity and low labor intensity. There is no need to set beacons and level the mixture; it is enough to distribute it evenly in separate areas of the room. In a single horizontal level, the self-leveling compounds will spread on their own; the master will only have to expel the air bubbles with a needle roller.

Classification of self-leveling floors

The industry produces self-leveling mixtures based on organic resins (epoxy, polymer) and mineral binders (gypsum, cement). Polymer self-leveling floors are:

• epoxy-urethane - a rational combination of plasticity and rigidity of the layer;
• methyl methacrylate - an expensive product for outdoor use and unheated rooms;
• epoxy - prohibited in living rooms, they are moisture resistant, but are destroyed by shock and vibration loads;
• polyurethane - vibration- and impact-resistant, very expensive.

Classification of polymer self-leveling floors.

Mineral self-leveling floors are often classified by layer thickness:

• starting – 5 – 10 cm, drying 6 – 12 hours;
• medium thickness – 2 – 5 cm – dry for 3 hours;
• finishing - allow you to bring horizontal surfaces to zero.

Depending on the operating conditions, self-leveling mixtures are recommended for use in the following premises:

• bathrooms - epoxy compounds;
• balconies, external stairs - polymer mixtures;
• living rooms - cement and gypsum levelers or polyurethane floors;

Important! If we talk about polymer self-leveling compositions, it is recommended to use only polyurethane floors in residential premises, because... only they meet all environmental and sanitary standards.

All of these materials fall into the category of self-leveling floors, since they almost do not need to be leveled. However, modifications based on mineral binder have a rough surface, are not strong enough (they emit dust when walked, although there are modifications that have sufficient wear resistance), and the surface does not have the necessary aesthetics of perception. They are used as perfectly smooth, quick-drying screeds for floor coverings, or as a finishing coating for industrial and warehouse premises.

Self-leveling polymer flooring has a self-sufficient design and wear resistance, therefore it is used as an independent finishing coating.

Self-leveling floor manufacturing technology

Unlike screeds, self-leveling mixtures are capricious in terms of the quality of the base; it is forbidden to lay waterproofing and insulation under them (except for starting compounds), since adhesion to the load-bearing surface is sharply reduced. Self-leveling floors are very expensive, they are usually used for a thin layer, and are combined with cement-sand screeds, so it is necessary to choose a rational manufacturing technology.

Pulling the self-leveling floor to zero.

Self-leveling mortars have high linear expansion, therefore they are cut off from the walls by a damping layer, are never rigidly connected to the building envelope and are not reinforced with wire mesh.

Requirements for grounds

The budget for finishing the premises dictates the main condition - efficiency. Self-leveling floors are applied in a thin layer, so it is extremely important to fulfill the following requirements:

Important! The self-leveling floor should be distributed only onto concrete surfaces that have gained strength and have minimal moisture.

Since mineral mixtures are used for leveling and are not a decorative coating, the requirements for bases are less stringent. For a polymer self-leveling floor, even fine dust, moisture and the master’s luxuriant hair are dangerous. Therefore, professional vacuum cleaners are used, finishers work in disposable suits with elastic bands on the cuffs, hats and respirators.

Damping layer and expansion joints

Unlike a floor on the ground and a concrete screed, the damper layer on the walls of the room along its perimeter is made exclusively from damper tape. Pieces of extruded polystyrene foam are not suitable for this technology. In addition to the vertical load-bearing surfaces, the entire height of the self-leveling floor, with a margin of 2 - 3 cm, is covered with tape over the communications passing through the floor/ceiling (hot water/hot water risers, heating, sewerage).

Damper tape sticker.

The horizontal level is marked using the tape, taking into account the highest point inside the room and the general level of all rooms of the apartment.

Horizontal level tapping.

In large premises (utility unit, garage, terrace, studio room), individual areas larger than 50 m2 are separated by a special profile (corner) to create expansion joints. In small rooms, the expansion joint runs along the bottom of the doorways and is decorated with threshold strips during finishing.

Expansion joint of self-leveling floor.

Economical screed schemes

The main secrets of choosing economical self-leveling floor manufacturing schemes are:

lowering the level - if the highest horizontal “zero” mark is located inside the apartment, a layer of self-leveling floor near the door in the hallway will inevitably create a step that is not comfortable when using the home, so you can deliberately lower the zero level, but only within 2 cm, which will be unnoticeable even in rooms 10 m2 or less;

Lowering the floor level.

For small differences in height, the required amount of self-leveling floor is used without a concrete screed.

Mixing the solution

Since pouring in one step is preferable, and the lifespan of the solution is not too long, the technology for mixing self-leveling floors has the following nuances:

Advice! If the ratios of components are indicated incorrectly by the manufacturer (range ±1 liter per bag of product), it is recommended to measure the spreadability yourself to select the optimal amount of liquid.

To check spreadability, the following technique is used:

• a ring is cut out of a 5 liter plastic bottle;
• installed on a smooth, slippery surface (tile, glass);
• is filled completely with the solution and carefully removed through the top.

The ideal spreading option is that the solution spreads after removing the ring to a diameter three times the size of the bottle (60 cm spot for a 20 cm cylinder).

Laying the mixture

The finished solution is applied to individual areas of the base, taking into account the spreadability of 1/3 and the thickness of the layer along the horizontal marks on the damper tape. If necessary, redistribution of the mixture is done with a spatula/trowel 20–30 cm from the dumped pile of mortar.

Laying begins from the corner farthest from the entrance opening of the room, the master moves inside the room on special paint shoes, periodically expelling air from the solution with a needle roller.

Trimming the damper tape

Excess damping material in height is removed with a utility knife after the mixture has hardened. Walking is possible after 3 – 12 hours depending on the composition; full strength gains take longer.

Trimming the damper tape.

If the self-leveling floor is intended as a finishing layer, additional sanding and varnishing may be required. Finishing coatings are installed on the starting self-leveling floors, not reaching the walls around the perimeter of the room. The remaining gap is decorated with platbands, which are fixed to the walls, and not to the screed.

Thus, the method of pouring a self-leveling floor is much simpler and more economical. Than traditional cement-sand screed. The technology is available to a home craftsman with minimal finishing skills and a small arsenal of tools.

How to properly pour a self-leveling floor onto a screed

Since a self-leveling self-leveling floor is suitable as a quick-hardening screed and an independent finishing coating, the technologies are somewhat different. This manual discusses exclusively the nuances of a self-leveling self-leveling floor for finishing coating.

Types of self-leveling floors

When installing a self-leveling screed, it is not enough to know how long the material takes to dry. It is necessary to take into account all the features of self-leveling floors (LP) in the complex:

• Base material:

You can pour a mixture of any cementitious material onto floor slabs and concrete screeds. If the design has heated floor contours, dry mixtures with a mineral binder are recommended.

Before pouring, it is necessary to remove porcelain tiles (tiles and mosaics), hardboard (fibreboard), and bitumen waterproofing materials from the surface. When installing a screed on extruded polystyrene foam, plywood and other wooden coverings, you will first have to pour a 4 cm floating screed reinforced with wire mesh.

There are options for rough (10 - 100 mm), fine (1 - 10 mm) leveling. Most mixtures cannot be brought to zero, so it is necessary to increase the floor height in all areas.

Mixture consumption depending on the thickness of the screed.

• Operating conditions:

For terraces, balconies, verandas, loggias and other rooms without heating, a frost-resistant NP is required - acrylic-cement, cement or polyurethane, MMA. Cement, gypsum and methyl methacrylate floors are usually used in apartments. For bathrooms, a quick-drying mixture is preferable; warehouse and garage floors should be highly wear-resistant.

Self-leveling floor on the balcony.

• Finish coating:

For linoleum and laminate, budget options based on gypsum or cement are preferable. Any mineral mixture is suitable for porcelain tiles and tiles in a dry room; in bathrooms it is better to use a complex binder or cement base.

Gypsum dries quickly (2 – 5 hours), but is not strong enough for the finishing layer and walk-through areas. Cement screed is highly durable, but it takes a long time to harden (more than 2 days) and does not have decorative properties. Therefore, polyurethane-cement mixtures (abrasion resistance, strength) and acrylic-cement compositions (frost resistance and lack of delamination) are produced.

Epoxy resins are prohibited in residential premises; they are used for garages and industrial facilities; they harden within 24 hours. Polyurethane self-leveling flooring is expensive, but it has no disadvantages and dries in 12–20 hours. The only disadvantage of MMA binder is the unpleasant odor of the material and very fast setting (30 minutes).

Manufacturing technology

You can correctly pour screed from self-leveling mixtures inside heated and cold rooms. The technology is more expensive, but allows savings in the finishing process due to less consumption of tile adhesive. The frost-resistant self-leveling floor does not require additional cladding, unlike a concrete screed. The structure can withstand similar loads, but already has a decorative finishing layer by default.

Preparing the base

The installation of screeds using dry mixtures that self-level under their own weight is much more expensive than using ready-mixed concrete. Therefore, you should comply with the requirements of the NP technology so as not to waste the repair/finishing budget in vain and not to correct your own mistakes. The main requirements for a cement or concrete base are:

• absence of defective areas - cracks are filled with a spatula (chamfer at the edges at 45 degrees), puttied, loose surfaces are removed or treated with reinforcing compounds;
• dust removal - the composition of the self-leveling floor is balanced by the manufacturer, so third-party inclusions, inevitably mixed with the components of the NP, reduce the strength and adhesion to the base material;

Pasting walls with damper tape.

Pouring NP refers to wet technologies, since when the self-leveling screed dries, the humidity in the premises increases. Therefore, preparatory finishing or repair operations can also include partial installation of false panels and gypsum board partitions. Contact with wet screeds is contraindicated for plasterboard structures. Therefore, the technology is used:

• the frame of partitions and false panels is mounted before pouring;
• double-sided sheathing of the sheathing is carried out with narrow strips of plasterboard near the floor;
• A damper tape is glued to the gypsum board.

Frame for the partition before pouring the self-leveling floor.

After the NP is poured and dried, the gypsum plasterboard systems are finished. At the same time, the drywall will not absorb moisture and will retain its strength and rigidity.

Advice! It is better to carry out painting work in rooms after curling the NP, so as not to scrape off paint stains from the base, which reduce the adhesion of materials.

Preparing the mixture

To fill NP correctly, you must comply with the conditions specified by the manufacturer on the packaging of the dry mixture:

• the material is added to the container with water, and not vice versa;
• bags with NP should be located in close proximity to the workplace, since the lifespan of the solution is usually limited to 30 - 120 minutes;
• The cement self-leveling floor traditionally includes a filler - fine sand, so it is forbidden to stretch the solution further than 30 - 50 cm from the pouring point;
• After the initial mixing with a mixer, the product must settle (5 - 15 minutes from different manufacturers, depending on the type of binder), since chemical hydration processes begin inside it, then it is re-mixed and poured onto the base.

Some companies indicate the ratios of NP components in a fairly wide range (for example, 8 - 9 liters of water per bag of mixture). Therefore, when mixing, you can determine the quality yourself. Recommended spreadability is 1/3, that is:

• if you cut off the bottom of the lid of a plastic bottle with a diameter of 5 cm;
• install the resulting ring on a smooth surface (glass, tile);
• and fill it with the prepared solution;
• After removing the ring, the mixture should spread into a spot with a diameter of about 15 cm.

Checking the spreadability of the solution.

If the spreadability is insufficient, it is necessary to add water; if the solution area increases to more than 15 cm, it is necessary to increase the content of the dry mixture.

Fill

To walk on a self-leveling floor spilled onto the surface of the base, it is correct to use paint shoes or special soles with spikes, which can be fixed with tape on any shoe.

Paint trowels for making screeds.

Unlike concrete screeds, the mixture is leveled minimally with a spatula, but it is necessary to remove air from it to ensure a homogeneous structure of the screed without internal cavities. For this, a needle roller is used (issue price is 500 rubles), mounted on a long wooden or plastic handle.

A regular or frost-resistant self-leveling floor is poured out of the container in which the mixing was carried out in a small layer and spread over the surface of the floor slab or existing screed, first with a spatula, then repeatedly with a needle roller.

The installation of perfectly smooth surfaces with a self-leveling floor has nuances:

• it is forbidden to pour the solution in one place, since NPs self-level only when applied approximately equally to all areas, so you need to distribute it with a spatula;
• work begins on the wall farthest from the entrance door to the room;
• due to the variety of mixture compositions, it is necessary to follow the recommendations of the specific manufacturer;
• after the specified time, you can walk on the floor, but only to perform other operations (for example, trimming the damper tape to height);
• laying of the finishing floor covering is carried out after 5 - 7 days, which is also indicated on the packaging of the mixture from a specific manufacturer

If all of the above conditions are met, the self-leveling self-leveling floor will provide a perfectly flat horizontal level, will have the declared properties, will not crack and will not shrink over time.

Important! The supply of hot water to the heated floor circuits is allowed 7–8 days after the self-leveling screed has completely dried and hardened.

Thus, pouring a self-leveling floor with self-leveling properties can be done on your own, even with minimal experience in finishing work. The basic requirements are stated by manufacturers on the packaging of dry mixtures, which allows you to avoid mistakes.

Advice! If you need repairmen, there is a very convenient service for selecting them. Just send in the form below a detailed description of the work that needs to be performed and you will receive proposals with prices from construction teams and companies by email. You can see reviews about each of them and photographs with examples of work. It's FREE and there's no obligation.

Ceramic tile heater - cheap and practical

Self-leveling self-leveling flooring is one of the best options for flooring in an apartment or country house. Self-leveling solutions are used as a base for other materials or as an independent coating. The mixture for self-leveling floor can be poured in any room from the bedroom to the garage or workshop. The main thing is to choose the right mixtures. Their range today is quite wide and includes coatings with different compositions, surface structures and layer thicknesses. Each of the mixtures has its own characteristics, pouring technology and recommended area of ​​application.

What does self-leveling floor consist of?

The main characteristic of any mixture for self-leveling flooring is its composition. Depending on the components used for the production of flooring, there are four main types of compositions:

1. The most common are floors with a cement binder. They are quite easy to install, durable and wear-resistant. To the positive characteristics we can add relatively low cost and a large selection of manufacturers.
2. Gypsum-based solutions are also quite popular. They are distinguished by high strength and durability, as well as the ability to fill fairly thick layers. A significant disadvantage of mixtures with a gypsum binder is their rapid wear in rooms with high humidity.
3. Self-leveling floor mixtures based on polymers and polyurethane are the highest quality coatings. They are particularly strong and durable. Laying them will require a lot of effort and experience, but the result is an ultra-thin screed. It is from this type of mixture that it is possible to obtain a floor covering with excellent artistic characteristics. Masters manage to create real masterpieces.
4. Combined compositions are produced based on cement and polymer resins. Their price is lower than that of polymer mixtures, and their quality is higher than that of cement mixtures.

Let's look at each in more detail.

Cement self-leveling mixtures

The mixture contains three main components: cement, sand and water. Only high-quality cement is used that does not contain foreign impurities. Only in this case will the screed acquire the necessary hardness after drying. The second component is pre-cleaned sand. For self-leveling floors, it is recommended to use medium fractions. Water for mixing mixtures should not contain any chemical impurities. It is desirable that the pH and salt levels are within normal limits.

In addition, the composition includes the following necessary components for self-leveling floors: plasticizers, antifreeze additives, acidity modulators and moisture-retaining additives. These chemicals give the cement mortar plasticity and the ability to flow over the surface of the base.

Note: Cement self-leveling mortars have the lowest cost among all types of mixtures. To pour such solutions, no special skills are required; even a beginner who is far from construction can do the job. These factors explain the popularity of this type of self-leveling coatings.

In those rooms where the base level has significant differences, depressions and cracks, cement mortars are used as a starting coating, and more expensive polymer mixtures are poured on top. This way it is possible to reduce repair costs, and it is much easier to fill on an already prepared base.

Cement-based mixtures are suitable for use in living rooms and various utility rooms.

Gypsum-based mixtures

The components of a gypsum-based self-leveling floor are almost no different from similar cement mixtures. The only difference is that gypsum is used as a binder. All features of such a self-leveling mixture are related to the characteristics of the binder component. Thus, gypsum hardens faster and allows you to create a thicker screed. When choosing a composition for pouring, you should remember that gypsum is not resistant to high humidity.

Advice: In this regard, the gypsum composition of the self-leveling floor is recommended for use in dry rooms for various purposes with light loads on the floor.

Polymer compositions for pouring floors

Polymer compounds occupy a special place among mixtures. What does a polymer-based self-leveling floor consist of?

Polyurethane solutions include polyurethane as a binder and various chemical additives that increase the plasticity and uniformity of the solution. In addition, quartz filler can be added to the composition to increase strength and wear resistance. As a rule, two-component self-leveling floors with fillers are used in rooms where the floor covering will be subject to regular high loads.

In methyl methacrylate solutions, the role of a binder is played by the resin. As the floor hardens, it acquires a high degree of strength and has a perfectly flat surface. To improve the quality of the coating, sand, plasticizer and various hardeners are added to the floor mixture.

Epoxy self-leveling floors, made from epoxy resin, are most often used in large areas, industrial or industrial buildings, where the floor covering will regularly experience enormous loads.

Tip: Cement-acrylic mortars are suitable for rooms with high humidity, as they are not susceptible to moisture.

Calculation of the amount of mixture and its preparation

After you familiarize yourself with the characteristics, read the reviews and decide which mixtures are most suitable for filling the floor, you will need to calculate the required amount of composition. The density of the self-leveling floor mixture is 1.3 kg/l per 1 m2. To fill a layer of 1 mm for each square meter of floor you will need 1.3 kg of dry powder, for a floor of 2 mm - 2.6 kg, and so on.

How to make your own self-leveling floor mixture? There are a few basic rules to remember. The powder should be poured into a container with water, and not vice versa. This way you will be able to obtain a solution of uniform consistency. The amount of water is calculated according to the recommendations on the packaging. It is best to mix the solution with a drill with a special attachment. Particular attention should also be paid to the time during which the mixture thickens, and all work should be planned in such a way as to use the prepared solution before it begins to set.

To improve the quality of the coating and simplify the work on installing the floor, builders and apartment owners are increasingly using a self-leveling mixture for self-leveling floors.

Such compositions are easy to prepare and work with, as a rule, do not require special skills and are affordable. The building materials market surprises with the variety of SCM for self-leveling floors, of varying quality and characteristics. Let's consider the specifics of using the mixture, what the self-leveling floor is made of, and the main properties of the pouring result.

Depending on the room in which the work is planned, as well as what result is needed, different compositions are recommended for use.

Mixtures for self-leveling floors for finishing and rough filling differ in the thickness of the possible layer, drying time, strength and, of course, price.

It is customary to distinguish between types of mixtures using the following criteria:

• fill layer thickness;
• type of diluent: aqueous or solvent;
• electrical conductivity coefficient;
• layer texture;
• base binder.

Most of the basic properties of the mixture for self-leveling floors depend on the main binder

Basic component	Scope of application	pros	Minuses
Gypsum	Rooms with low humidity (up to 70%)	The thickness of the leveling layer can reach 10 cm, which makes it possible to hide very significant differences in height at the base; Low thermal conductivity; Budget cost.	The readiness period and drying period are longer than that of cement mortar; They lose strength at high humidity.
Cement	No limits	Fast coating ready time; Not susceptible to high humidity; High strength.	High price; Thin layer filling up to 5cm.
Epoxy resin or methyl methacrylate	Without restrictions, most often for non-residential premises.	Daily availability of coating; Excellent design and decorative capabilities; Can be applied over 3D layouts; Increased wear resistance.	Not suitable for leveling significant surface defects; Toxic when working; High solution consumption: more than 1.5 kg per 1 m2.
Polyurethane (polyaspartates)	Most often used in private construction.	High strength; non-slip, abrasion-resistant; Suitable for filling inclined surfaces without the formation of sagging.	Not resistant to mechanical damage; Long readiness cycle; High price

Work stage

The rough screed is poured in a thick layer

Among other things, the mixture for self-leveling floors should be distinguished according to the stage of work it carries out. For the main or black screed, levelers are used. These mixtures are poured over beacons with a large layer thickness.

Used to eliminate gross defects in ceilings and height differences. This type of fill dries quickly. You can save on volume by laying reinforcing mesh in a layer.

The top fill should be no more than 5 cm thick

The top leveling fill for decorative finishing is carried out with appropriate compounds in a thin layer of no more than 5 mm.

The mixtures are expensive and are used as final leveling.

The solution sets quickly, but final hardening comes with time.

Some types of mixtures are poured as a decorative coating, usually an epoxy fill for 3D floors.

It is important to understand that finishing mixtures can be applied to virtually any base, as indicated on the packaging. But when using a certain brand of self-leveling floor composition for a screed, you will have to use a finishing fill of the same brand.

Compositions

The binder component of the mixture is mixed with mineral additives

Many people will decide that everything is simple, just mix the floor mixture with your own hands and save money. In theory, self-leveling flooring is not complicated in composition. Moreover, most manufacturers do not hide the elements of the mixture and write them on the packaging.

As mentioned above, there is always one binder component, to which various mineral fillers, additives, additives and, of course, sand are added.

All these components perform their function and are mixed in a certain proportion. And even if you find the proportions and recipe, which manufacturers usually hide, there will still be a lot of fine edges. What kind of sand? Which faction? What to mix and in what order.

In the end, it is unlikely that you will be able to save money. Rather, spend extra on ready-made dry construction mixture.

It is quite possible to prepare less complex mixtures for rough screeds yourself.

Before purchasing a mixture, evaluate your capabilities, both financial and physical, if you carry out the work yourself. To learn how to fill such floors, watch this video:

And a few simple tips to help you decide on a purchase:

The evenness of the prepared floor directly affects the service life of the decorative coating, so you should not save at this stage.

The self-leveling floor owes its name to the method of its installation - this is an option for making a screed by pouring a self-leveling mixture. A distinctive feature of cement self-leveling flooring is its thickness, which is about 3.5 mm. Sometimes cement self-leveling flooring is called liquid linoleum - in fact, its surface is perfectly smooth and even, like tiles, only there are no seams on it. This floor can be safely used in public and residential premises, it is environmentally friendly, its installation and operation are safe for people. Self-leveling, cement-based flooring is the optimal solution for creating a heated floor system.

Liquid floors are usually used as a basis for creating a fine finish - laminate, parquet, and linoleum are laid on it. In most cases, they resort to purchasing ready-made dry mixtures; the retail chain has a wide range of products from domestic and foreign manufacturers.

The mixture for filling the floor includes:

• cement as a binder component,
• fractional sand,
• mineral supplements,
• polymer fillers.

Cement mixtures that do not contain additives have high quality characteristics, but to ensure a self-flowing texture, you will need to add a large amount of water. This point can lead to a decrease in the strength of the coating. The problem can be solved by the presence of polymer additives in mixtures. To obtain a high-quality result, you only need strict adherence to the technology of performing the work. Looking at the self-leveling cement floor in the photo, one can only be amazed at the ideal appearance of its surface.

As for the choice of the mixture from which the cement self-leveling floor will be made, the price sometimes plays a decisive role here. When choosing between expensive organic-based and cement-based self-leveling floors, preference is often given to the latter - the cost of such a product is much lower.

We install a self-leveling cement floor with our own hands - preparatory work

The process can be divided into several stages. Preparatory - consists of cleaning the surface of the floor and walls from dust. Next, mark a line at which the floor level will be located, and glue polystyrene foam adhesive tape, which has a spongy structure, along it. The width of the damper tape corresponds to the thickness of the self-leveling coating. If it turns out that inaccuracies were made when gluing the tape, then the parts of the tape protruding beyond the edge of the floor are hidden under the baseboard.

Primer - it is applied to a clean surface in any way, using a roller, brush, or spray. Treatment of all cracks and roughness is required.

It will take about half an hour for the primer to dry; to enhance the effect, the procedure is repeated 1 or 2 more times until a damp shine is obtained. Particular attention is paid to loose, old foundations. New concrete surfaces can be primed in one coat. If darkening and foaming occurs when applying the primer, you should expect a longer drying period due to the increased level of humidity in the room. It will take 6 to 24 hours for the primer to dry completely.

After this time, you can begin installing beacons; this procedure is especially important for rooms with a large area, in which case uniform application of the cement composition can be difficult. The installation of beacons divides the area into segments and allows you to fill the mixture in stages. The cement solution is prepared before installing the beacons, this will make it possible to begin work immediately.

The height of the beacons must correspond to the planned thickness of the self-leveling floor. If the floor surface is flat, self-tapping screws are used as beacons; they are screwed into the floor at a distance of about 1 m in a checkerboard pattern. If there are significant differences on the floor, from 3 cm or more, then metal corners can be used as beacons; they are attached to the floor using gypsum or cement mortar. The correctness of their installation is checked using a building level; strictly observing the horizontal line is mandatory.

If the room has a very large area, then they resort to another method of installing beacons - large areas usually require a thick leveling layer. In this case, the same screws screwed into the base can serve as beacons; marks are made on the walls at the height of the screw heads. The horizontalness is checked using a level, then a thin wire is pulled between the marks. Next, the floor is poured.

How to prepare the leveling mixture

You can begin preparing the mixture for filling the floor only after making sure that the solution under the beacons has completely hardened. Carefully study the instructions on the packaging of the mixture. Pour the amount of water specified in the instructions into the prepared container, and carefully pour the contents of the package into it. It is not recommended to add any foreign substances to the solution.

To obtain a high-quality mixture, it is better to use a drill with an attachment or a construction mixer. After the mass reaches a homogeneous consistency, leave it for a few minutes, then stir well again. It is not recommended to set a high speed on a drill or mixer - a better mixture is obtained at low speeds.

Pouring the floor

The pouring process lasts half an hour - this is the time during which the solution is suitable for use. For this reason, it is better to do the work with assistants. The prepared solution is poured onto the floor surface and leveled using rollers.

To avoid haste, sometimes the solution is prepared in portions, for example, the first portion of the solution is prepared, one of the workers levels it, the second prepares the next one, immediately after leveling the first, the second part of the mixture is poured out and also leveled.

The surface obtained in this way will be even and smooth, it will not have seams. A large room is divided into several parts and gradually they are filled. This is how a cement self-leveling floor is made; in the video you can see this process in more detail.

Having completed pouring the floor, it is rolled with a special roller with needles on the surface - this will ensure a better fit of the solution to the base, and will also remove air bubbles from the solution.

You can walk on wet floors in boots with spikes or shoes with metal pads. It takes about 6 hours for the mixture to dry; usually the exact drying time is indicated on the packaging with the mixture.

A cement self-leveling floor, the manufacturing technology of which is quite simple, can be made with your own hands. The bulk of the work will be preparatory work. But, despite the time spent and efforts made, the results of the work will definitely please you with a perfectly leveled floor surface.

Cement-acrylic self-leveling floors

Initially, this type of self-leveling floor was developed for installation in food industry facilities. The polyacrylate copolymer included in its composition provides high strength and protection from moisture and chemical reagents.

Cement-acrylic floors are used inside and outside buildings, taking into account the possibility of their operation at high and sub-zero temperatures.

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Before installing the finishing floor coverings, it is necessary to carry out work to level the base. Modern building materials provide the opportunity to achieve an ideal, even surface in different ways. The range of materials and technologies is quite large: from the construction of floorings from sheet materials of sufficient strength to the production of “wet” screeds using cement-sand mixtures or self-leveling (self-leveling) compounds. What is better: self-leveling floor or cement screed? To decide on the advisability of using one or another base, it is necessary to understand their features and subtleties of application.

Screed and self-leveling floors differ from each other according to several criteria:

• time costs and labor intensity of work;
• cost of materials and labor;
• compatibility with the material of the top finishing flooring;
• Possibility of use at various height differences.

The feasibility of using a self-leveling floor is high when it is necessary to perfectly level the surface and carry out work in the shortest possible time. Self-leveling flooring is not suitable for use with large differences in height and for laying finishing materials such as tiles, stone, porcelain stoneware. Despite the relatively low labor intensity, the cost of installation and material for a self-leveling floor are high compared to a concrete screed.

Concrete screed perfectly levels the surface, its cost is relatively cheap, however, the process of leveling the floor is labor-intensive and time-consuming. Concrete screed involves the need to deliver many bags of cement and sand to the site being repaired and mixing the mortar manually. Therefore, when carrying out repair work in a multi-storey building, it is necessary to understand that the high location of the object increases the cost of the cement screed due to the need to lift the material to the floor. Cement screed dries quite slowly and the rate of hardening directly depends on the thickness of the layer.


Concrete floor screed

Brief information about the features of concrete screed

Over time, cracks and scratches appear on the concrete surface, which inevitably leads to the need to level the flooring. It is impossible to efficiently install or replace laminated or parquet flooring or linoleum without restoring the concrete screed. The minimum thickness of pouring the concrete mixture when eliminating deficiencies in the existing concrete screed is 30 millimeters.
TIP: The surface of the concrete screed must be additionally sanded if relatively thin linoleum is to be laid. However, sanding costs extra money.
Specialists make concrete screeds using beacons; it is this technology that allows you to maintain the required level throughout the entire room. The need to use beacons and manually level the mixture with a special tool also makes the process labor-intensive and classifies the screeding process as low-tech.

IMPORTANT: Experienced specialists note the positive aspect of using a screed - elements of the “warm floor” system can be immediately laid inside it.

The advantage of a concrete screed: it can be used to install a heated floor system

Brief information about the features of self-leveling floors

Self-leveling flooring, which is a self-leveling gravitational composition, is used for surfaces with small differences in height. This type of substrate can withstand heavy loads, including high wear resistance and does not wear out.

Composition of working mixtures and their features

The physico-chemical properties of the materials that make up the cement-sand screed and self-leveling mixture determine the differences in the implementation of floor pouring technologies.

"Wet" cement screed

The traditional composition for wet cement-sand screed consists of three components: sifted sand, cement and water. Its preparation is carried out by the masters themselves by kneading immediately before use. At the same time, the proportions of elements are also regulated situationally, so the human factor plays an important role here. There is a ready-made dry mixture for cement-sand screed, which is only diluted with water. This mixture contains a small amount of profile modifiers. Modifiers increase the manufacturability of installation and improve the performance characteristics of cement-sand screed, namely:

• improve the mobility of the solution;
• increase the initial setting period of the diluted mixture;
• increase the moisture resistance of the floor;
• increase the strength of the coating and its abrasion;
• increase resistance to deformation under temperature influences, which is important when additionally using “warm” floor technology.

IMPORTANT: With or without the use of modifiers, the process of laying cement-sand mixtures requires the processing of large volumes of materials, as well as significant effort to achieve the effect of a flat surface.

Semi-dry cement screed

By choosing a ratio of components in which the mixture is dominated by a larger amount of sand and relatively little water, it is possible to achieve the effect of rapid hardening of the prepared solution. Semi-dry screed has reduced strength; it often crumbles and splits, and cannot withstand heavy weight loads. This method is most often used in apartments with a small amount of lightweight furniture, during accelerated repairs.

Dry cement screed

When dry screeding, no water is used at all, since a dry mixture is used to fill the floors. This backfill is leveled mechanically and sheet materials - plywood or gypsum fiber - are placed on top. With its low weight, this screed is suitable for use in private houses on wooden floors.
TIP: “Wet” screed, as it is more durable, is more often used in non-residential premises (garages, retail spaces), other types of screed are preferable for apartments and houses with a relatively small area.

Dry screed is most suitable for use in apartments with a flat floor base

Self-leveling self-leveling screed

Compositions for self-leveling floors are manufactured factory-made in the form of dry mixtures or suspensions; they cannot be prepared independently. The mobile liquid consistency of the finished solution allows it to spread freely and level due to gravitational forces. Classification of self-leveling floors is made in accordance with the composition of the mixture. Mineral or polymer compounds can be included in the finished mixture, and therefore self-leveling floors are conventionally divided into:

• epoxy;
• polyurethane;
• epoxy-polyurethane;
• methyl methacrylate.

Polyurethane compounds are characterized by increased elasticity and moisture resistance; they are designed for use under conditions of significant loads and surface compression/expansion, as well as vibration and temperature changes.

An impact-resistant surface is obtained by using epoxy compounds. These two-component compounds are also impact-resistant and can withstand high-intensity mechanical impacts.

Epoxy-polyurethane mixtures are distinguished by strength, elasticity and elasticity, and in fact, combine the positive characteristics of mono-component epoxy and polyurethane mixtures.

If a high speed of hardening of the composition is required, it is necessary to use methyl methacrylate compositions - two hours after pouring it is possible to move on the floor surface.

Polyurethane floor screed

Features of coatings due to the compositions used

In addition to the main operational characteristics, when choosing the type of screed, it is necessary to evaluate other important parameters: time and method of preparation, installation, and other installation operations. These factors affect the final result, cost and time spent on floor repairs.

Cement-sand screed

The technological feature of this type of composition is its thick consistency and poor ductility. This necessitates the use of trowels, graters and rules, as well as significant physical effort to distribute the mass over the floor surface. In order to facilitate the application process, it is practiced to add modifiers to the mixture. If installation is carried out quickly and there are no factory modifiers, it is possible to add concentrated detergent to the composition - it also increases the plasticity of the mixture. For large differences in heights, the “beacon” laying technology is used; it is characterized by a general increase in the cost of work and additional labor costs.
IMPORTANT: The cement-sand screed solution is prepared immediately before use using cement sand and a variable amount of water. The quality and composition of the solution is complete. Depends
from the human factor and the skill of the performer - incorrect use of the proportions of materials when mixing the mixture can lead to
to its fragility and cracking.

Scope of application of cement-sand screed

Due to the pronounced roughness of the surface of the cement-sand screed, it is used as a basis for laying linoleum, parquet, laminate, floor boards, and carpet.

For technical or industrial premises, cement screed is sometimes used as a finishing coating. The top layer of the screed is strengthened for its further use using ironing technology, in which cement laitance is squeezed onto the surface of the mortar and dry cement or other powder toppings are rubbed into it, which compact the outer layer of the screed and strengthen it. The surface thus reinforced can withstand the use of heavy equipment, including forklifts.

For residential premises, the minimum thickness of the screed is 3-4 centimeters. To prevent mechanical damage and cracking, it is practiced to place a reinforcing metal or polymer mesh inside the composition. After 12 hours after pouring the cement-sand screed solution, it is possible to carefully move along its surface in soft shoes. Nominal strength is achieved after 14 days, after which installation of decorative finishing materials is possible. The final hardening of the solution occurs within 90 days. When using wood materials as a finishing floor covering, it is necessary to take into account the moisture content of the base, namely, the base must be completely dry.

Floor surface polishing machine

Screed using self-leveling floor

Installation of the self-leveling floor is carried out without “beacons”; the filling technology is simple and does not require significant specialist effort. Due to the fluidity of the solution and its ability to self-level and quickly dry, the installation process is fast and efficient.

Scope of application of self-leveling floors

The quality of the resulting surface of self-leveling floors allows you to lay absolutely any decorative coating on top. Often, self-leveling floors are left as a finishing coating due to its attractive appearance and the possibility of various decoration methods during the installation process.

Polymer self-leveling screed has a rich color palette; in addition, glitter, flock and other decorative decorations can be used. So-called 3D floors are gaining popularity. An impressive appearance and a variety of fantasy images are achieved by installing a high-resolution printed vinyl image in the middle layer, and filling it with a layer of transparent polyurethane or epoxy component on top.
Tip: Using a similar technology, it is also possible to produce some interior items, in particular tables, whose design will repeat the design of the floors.
Self-leveling floors are popular for food, chemical, and pharmaceutical premises, as well as in gyms and fitness clubs, public institutions, and kitchens in catering establishments, that is, where sterility and cleanliness, ease of maintenance and disinfection of surfaces are important.

For domestic premises, self-leveling floors are indispensable in bathrooms, kitchens - in areas where there are pronounced temperature fluctuations and high humidity.

After 3 hours after pouring the self-leveling mixture, you can already move on its surface, and after three days it is advisable to begin laying the decorative material.

The minimum permissible thickness for pouring the mixture is 0.5-1 mm, but generally, pouring is done at 3.5-5 mm. But with a minimum pouring thickness, floors are only suitable for home use, and for industrial use the thickness is calculated in accordance with the expected loads.

The process of pouring self-leveling floor

Features of the use of various screeds in practice

The advisability of using one or another type of screed or a combination of them depends on several factors.

An indicator for the use of cement-sand screed is the complex terrain of the floor, namely:

• large differences in height between floor slabs;
• significant unevenness, potholes;
• large angle of inclination of the plates.

These defects require the installation of a thick layer of screed, therefore, the advantage of using cement-sand mortars in this case is undeniable.

If it is necessary to achieve significant heat-saving characteristics of floors, for example, interfloor, perilite, expanded clay or polystyrene foam balls are added to the cement-sand screed. Heat-saving functions are not characteristic of self-leveling floors and heat-saving indicators cannot be achieved by adding any additives.
Advice: It is believed that you can make a self-leveling floor yourself, without resorting to the services of specialists.
The stages of surface preparation for all types of screed can be characterized as follows:

• cleaning floor slabs or existing rough fill;
• surface dust removal;
• treatment with primer compounds to ensure better adhesion.

Ready-made concrete floor screed

Combined screed method

If it is necessary to achieve a smooth floor surface with a highly deformed working surface, experts recommend using a combined method - first, make a layer of concrete screed over the entire surface or parts of it, and install a self-leveling floor on top. This method saves money by 40% compared to using only self-leveling floors on difficult surfaces.

Combined method of using concrete screed and self-leveling floor

Approximate cost calculation for screed

Self-leveling floors and screeds are designed to level the surface, but at the same time they differ in properties and cost. For clarity, it is possible to give an example of a conditional calculation of the costs of installing coatings, based on the conditional area of ​​the object of 100 square meters.

Initial data

Let's calculate a situation in which it is necessary to level the floor of 1009 square meters with a coating whose thickness will be equal to 10 centimeters. Three options seem possible:

• A mixture of high-quality sand concrete. Its average cost is 150 rubles per 50 kg, that is, 3 rubles per 1 kilogram;
• Cement screed with modifiers– the average price is 180 rubles per 25 kilogram, namely 7.2 rubles per kilogram;
• Composition for self-leveling floor– approximately 230 rubles per 20 kilograms (more than 11 rubles per kg).

For 10 square meters of object you will need:

• 2 kilograms per square meter of sand concrete, and its total cost will be 60 thousand rubles;
• 1.8 kilograms of modified screed, the total cost of this material will be 129,600 rubles;
• 1.6 kilograms per square meter of mixture for self-leveling floor, but, with a significant cost of one kilogram, 184,000 rubles will be spent on the material.

Based on the above calculations, it is obvious that when the thickness of the surface leveling is large, it is necessary to combine a cement-sand screed and a self-leveling floor.

Surface quality

For tiles, porcelain stoneware and stone, the mirror surface provided by the use of self-leveling floors is absolutely unnecessary.

Therefore, self-leveling flooring is used before laying the following materials:

• linoleum;
• laminate;
• parquet;
• carpet

It is these materials that require all the properties of a self-leveling floor, since they provide the final ideal appearance of the repaired floor.

Medium thicknesses for leveling

At medium differences, namely 2-3 centimeters, it is necessary to make a decision based on the current situation at the repair site, as well as in accordance with the intended design.

So, if you only need to lay linoleum or laminate and do it as quickly as possible, it is advisable to make a self-leveling floor. If installation of heated floors is required, then a cement-concrete screed is used, and at the request of the customer, an additional self-leveling floor is used.

In any case, one of the important determining factors in choosing the type of screed is time and the amount of money.

Advice: If you need to quickly make a high-quality coating and there is no goal of saving, self-leveling floors will be the ideal solution.

Final alignment

For high-quality finishing leveling with a thickness of 1-3 millimeters, only a self-leveling floor is used. It is important to keep in mind that any other screed will not adhere to the base and will crack due to the thinness of the layer.

Finished coating for laying laminate

Let's sum it up

For quick orientation when using types of screed, depending on the coating and leveling thickness, we present a general table.

Parquet, laminate, linoleum, carpet, other material requiring a flat surfaceTile, mosaic, stone, other material that requires a rough surfaceThin layer of fill from 0-5.mm Self-leveling floor Self-leveling floor The average filling layer is from 5-30.mm Self-leveling floor/screedModified screed The filling layer is thick, there is a significant difference in heights and defects - 30-200.mm Combined method - screed with self-leveling floorAny type of screed

Video: subtleties and secrets of self-leveling floors and liquid screeds