How to make a ceiling screed yourself?

Laying process floor coverings in an apartment quite often it comes up with a problem with uneven floors. To solve such problems, there is a floor screed. It is worth noting that it is with the screed that you need to begin the process of transforming the floor. The screed will eliminate unevenness and also add strength.

At the moment, cement-sand mixture (CSM) or special ready-made mixtures are the most common screed methods.

So, let's start making a ceiling screed

Before applying DSP, it is necessary to clean the surface of debris and dirt and be sure to prime it. The choice of primer type is made depending on the type and condition of the surface being treated.

Then, to prepare the surface, a special material is applied - a primer. Depending on the porosity of the surface, it is diluted with water or applied undiluted.

Now the most important thing is to determine the zero level, that is, the highest place on the surface. Beacons are placed from this place, between which it is recommended to stretch levels (rope, fishing line), after which it will be possible to visually assess the height of the future screed, and accordingly required volume material.

To make work easier, especially on large areas, beacon guides are used, which allow you to fill the DSP in strips and prevent the mixture from spreading. There are special guides on sale, but for these purposes it is quite possible to adapt improvised means, such as metal pipes or boards, the height of which does not exceed the future screed. The recommended distance between them is 1 meter.

DSP is applied in a checkerboard pattern, through one strip and leveled with a trowel or a flat board.

After hardening, the guides are removed, and DSP is applied to the remaining strips. It is not recommended to make the screed more than three centimeters high, otherwise it may become covered with cracks when it hardens.

If an increased load is planned for the future floor, it is necessary to reinforce the screed with a special mesh. In addition, reinforcement allows you to increase the height of the screed to ten centimeters.

While the screed is drying, there should be no sudden temperature changes or drafts in the room. It is also necessary to remember that complete drying of the screed occurs no earlier than 30-40 days.

A smooth, snow-white ceiling is considered by professionals to be the most important indicator of a flawlessly completed repair. Of course, this means someone who has not experienced the trends of modern fashion with its inherent complications, such as multi-levelness and refusal white. Making a ceiling screed is a labor-intensive task, but it is quite doable, and all the work can be done independently.

The use of plaster or leveling mixture especially in rooms with low ceilings where the possibilities for creating suspended structures, allows you to “save” the height of the room, and the use of natural materials makes the ceiling “breathable”.

The preparatory stage of work includes thorough cleaning of the ceiling surface from layers of old coatings and peeling plaster. It is also necessary to determine the greatest height difference. It should not exceed 50 mm if the ceiling screed is to be done using leveling mixtures.

For small differences (up to 5 mm) it will be enough to use leveling putties. On construction market You can find a fairly large assortment of putties that can be applied in a thick layer. The putty is applied to the surface and, after drying, treated with fine-grain sandpaper.

But if the difference is more than 20 mm, it is necessary to use a reinforcing mesh and then work with plaster. Painting (serpyanka) and metal grid. The serpyanka is glued to the ceiling with glue. PVA is most often used. All seams should also be sealed with mesh. You can also find self-adhesive serpyanka on sale. To secure the metal mesh, staples or nails with wide heads are used. This mesh is used if it is necessary to apply a layer of plaster more than 50 mm. Before plastering, the surface must be primed, for example, with concrete contact. Among modern materials that make it possible to eliminate significant differences, we can note, for example, Rotband mixtures.

Alignment quality control is carried out various methods. You can use beacons, which are often used as nails. They are driven in so that the caps lie in the same plane, and the ceiling is leveled along a thin rope or thread stretched between them, filling the gap between the thread and the surface with plaster.

Another way is to use a water level. At its core, this level is two communicating vessels filled with water. By applying level tubes in different places, the degree of surface leveling is assessed. More modern method– use of laser marking. With this device you can mark both vertical and horizontal lines.

After waiting the required period, a layer of leveling putty is applied to the dry plaster. Then they prime and paint, if this final finishing option is chosen. As a primer, you can take the same paint, diluted with the thinner indicated in the instructions for use, by 20 percent. If you decide to use a primer, then it is better to use it in tandem with paint from the same manufacturer.

Before you practice decorative finishing ceiling, its surface must be made perfectly flat. Only in this case the quality of work will be high. First of all, this condition must be met when ceiling, made from precast concrete slabs, which are not always perfectly installed. Therefore, first we do the ceiling screed, and only then move on to decorative design.

The answer to the question of why a ceiling screed is needed is quite simple. Reinforced concrete slabs- these are massive floor elements that, even with the help of technology, are difficult to install on one level, therefore, as a rule, there are some differences between them. Their size depends on the quality of installation of the ceiling: what better specialists and their work, the smaller the difference in the levels of the bottom of the slabs will be.

Of course, you don’t have to save money on your own home and call a team of specialists who can quickly and efficiently screed the ceiling. But if you study all the nuances of this process, you can try to do it yourself.

Before you begin screeding the ceiling surface, you need to decide on the method you will use. There are two types of screed ceiling surface: “wet” and “dry”. The first method involves the use of solutions or mixtures. It could be concrete screed ceiling made from cement mortar.

The second method requires the use of sheet materials such as plasterboard, plywood, fiberboard or chipboard. How to determine the right method for making a screed with your own hands? Of several criteria, it is worth paying attention to one main one. To do this, measure the difference at the junction of the plates. If it exceeds 5 cm, then wet screed will not work, since the thickness of the applied plaster will exceed the normalized value. This is fraught with the fact that, under the weight of its own weight, the plaster layer simply cannot withstand it and falls, and this can lead to human injuries.

In addition, a large thickness of plaster may exceed the standardized load for which the ceiling was designed, which will also lead to negative consequences. To prevent all this from happening, you should use a dry screed. Of course, she also has her shortcomings. For example, this method “steals” quite a lot of height from the room, so even without that low rooms will become even lower.

The plaster is a hardened concrete mixture, the application process of which is quite labor-intensive, especially on the ceiling surface. But this method of screeding the ceiling does not lose its relevance, because sometimes it is the only way to create a flat surface. In addition, you can plaster any coating: wood, concrete or metal. But in any case it is necessary to carry out preparatory work. They include several stages:

Cleaning the surface of contaminants, for example, mold or other fungal stains that need to be disinfected;
Removing old coating in the form of paint, whitewash, etc.;
Priming the concrete surface using strengthening mixtures;
For wooden and metal structures installation of reinforcing mesh is required.

Then they move on to the installation of beacons, which are then used to plaster the ceiling. Using a paint cord, you need to mark the zero level, which determines the lowest level of the ceiling surface. It will be the first lighthouse. The rest are installed every 30-50 cm on plaster marks. The height of the beacons should not be greater than the thickness of the plaster, that is, 5 cm.

After installing the beacons, you can begin plastering. To do this, you need to make a working solution based on gypsum, cement or lime. Then follow these simple instructions shown in the video:

Apply the first layer of spray without leveling;
Distribute several primer layers, gradually leveling the plaster;
After applying the last layer, remove the marks with beacons and fill the recesses remaining from them with the solution;
Using a rule applied along, across and diagonally to the ceiling, check the evenness of the surface (excess plaster is cut off, and, on the contrary, more mortar is added to the missing places);
Seal with a grater internal corners and places where the ceiling meets the walls;
Apply a final, carefully leveled coat to create a smooth surface.

When applying plaster, be sure to ensure that no defects in the form of shells or pits are formed. After the rough screed you can apply finishing coat in the form of putty.

Do-it-yourself dry ceiling screed can be made from plasterboard, which serves as a high-quality alternative to the long and labor-intensive method using plaster.

As can be seen in the photo, using plasterboard sheets designers implement different ideas and ideas in interior design, which is a definite advantage.

In addition, simplicity and speed of installation can also be attributed to the advantages of dry screed. The sequence of work includes only three stages:

Marking the ceiling surface, when the zero level is placed on the walls, the corners and frame are marked, and options for laying out plasterboard sheets are determined so that their shift is equal to the pitch of the sheathing;
Installation of the frame structure is a stage that involves fastening guides, which can be made of wood (attached with screws or direct hangers) or metal (fastened only with direct hangers);
Cutting and installation of plasterboard sheets according to the drawing.

Screeding the ceiling with your own hands is possible, despite its labor intensity. The main thing is to follow the installation steps and recommendations of specialists. Then the ceiling with its evenness and beauty will only emphasize the interior design.

Perfectly flat ceiling surface - required condition, which must be observed before decorative finishing of this surface, so that the quality of the work carried out is high level. This is especially true for ceilings made of reinforced concrete slabs. The evenness of the ceiling is achieved after the ceiling has been dry screeded.

A perfectly flat ceiling surface is a prerequisite that must be met before decorative finishing of this surface.

The difficulty in leveling the surface of reinforced concrete slabs (unlike others) lies in the fact that most often they do not lie in the same plane, but there are significant differences between them. In any newspaper you can find advertisements in which professional builders For a certain fee they will do everything quickly and efficiently. But if you want to save money, then you can try to do everything yourself, based on the recommendations of experts. Moreover, the described nuances are suitable for almost any ceilings.

There are two known ways to level (screed) the ceiling:

“Wet” screed involves the use of special solutions and mixtures, and “dry” screed involves leveling the ceiling surface using sheet material. These include:

drywall;
plywood;
Fiberboard, chipboard and many others.

There are several criteria for choosing a ceiling screed method, but the main one is that if the differences at the joints are more than 50 mm, then you should choose the “dry” leveling method, since the thickness of the plaster layer will exceed permissible norm and may fall off during operation, causing serious injury to a person.

It should also be noted that “dry” ceiling screed significantly reduces the height of the room, which is not very beneficial for low ceilings. In this case, it is more advisable to use putty for leveling (provided there are small differences).

To work, you will need to prepare the following tools and devices:

In preparation for screeding, remove the previous layer from the ceiling. finishing material, whitewash, putty.

spatulas of different sizes;
aluminum rule;
metal smoother or grater;
plaster comb;
plaster falcon;
a plastic container with a volume of at least 18 liters;
drill with mixer attachment;
sponge grout.

Before you begin directly leveling the ceiling surface with your own hands, you need to prepare it, especially if this is not a newly built house. The layer of previous finishing material, whitewash, putty, etc. is removed from the ceiling.

To ensure that the work progresses quickly and not too tediously, you should use the recommendations of experts:

The plaster is removed with a sharp spatula, periodically sharpening it.

To make work easier, you can lengthen the handle of the spatula by screwing a wooden or plastic stick to it.

The plaster must first be moistened with a spray bottle or a foam sponge.

The layer will be much easier to remove water-based paint, if you add a few drops of iodine to the water.

The most difficult situation is with water-dispersion paint. Here you will need to use either a drill with a wire brush, or a special remover, which can be purchased at any hardware store.

a layer of old material is removed not only from the surface itself, but also from the tile joints. To do this, take a pick, hammer and spatula. Only the lagging and cracked part of the material needs to be removed;
if there is fungus on the surface, then you definitely need to pay attention to this problem. Otherwise, the new surface will suffer the same fate. First, the surface is treated with an antiseptic, which is either bought in a store or made by hand, and then it is primed to increase adhesion to the material.

Screeding the ceiling with your own hands begins with eliminating the largest defects using coarse putty for rough work. You can use tow, which is soaked in a solution of such putty and you get a kind of sponge for sealing cracks. To prevent the joints between the plates from cracking, they are reinforced with a special mesh, which is pressed into the layer of putty.

Before applying the second layer of putty, you need to “comb” the first one with a plaster comb, without waiting for it to harden.

After all of the above, they begin to putty the entire surface of the ceiling, for which the prepared mixture is applied to the base and carefully leveled with a spatula. The putty mixture is applied in a direction away from you, with a thickness of no more than 20 mm. Next, the layer is leveled with a rule of zigzag movements towards itself. Before applying the second layer, it is necessary to “comb” the first one with a plaster comb, without waiting for it to harden.

Only after two days can you begin to apply the next layer.

Combing the previous layer allows you to roughen the surface to increase the adhesion of materials.

The length of time the layers are kept is determined by the level of humidity in the room. If the room is dry and warm, then the plaster hardens very quickly, and high humidity promotes uniform hardening of the material.

It is necessary to take into account the fact that during work the air humidity increases, therefore, the plaster will not dry quickly. You should not change the humidity level artificially, since the layers of plaster must harden under the same conditions in which they were applied.

Concrete flooring is currently perhaps the most widespread in both residential and industrial construction. It is suitable for almost any finishing coating or can, after appropriate processing, be used independently. Its main advantages, subject to the filling technology, are high strength, resistance to destruction, and durability of use. It is not surprising that when conducting private construction or when renovating an apartment, in the vast majority of cases, homeowners opt for this particular flooring technology.

Is it worth inviting specialist builders, or is screeding a concrete floor with your own hands a completely affordable process for the average homeowner? This publication is devoted to answering these questions.

Types of concrete floor screeds

Concrete floor screeds may have different design, performed using slightly different technologies and intended for different purposes.

Thus, they can serve solely for leveling the floor, which is carried out before installing the finishing coating. Powerful screeds serve as a reliable foundation in rooms where increased mechanical loads are expected. They can also perform the functions of ensuring the required thermal balance, acting, for example, as powerful heat accumulators in “warm floor” systems. Screeds are often used to cover communication systems. They can they are used and in order to create a certain slope in those rooms where it is necessary.
Concrete screeds differ according to the number of layers:

— They can be single-layer, that is, poured simultaneously to the entire calculated height. This is usually used in industrial, commercial or utility applications. non-residential premises, where there are no increased requirements for the evenness of the floor.

— Multilayer screeds are poured in several stages. Typically, the first layer serves as a rough base, and the top one creates a smooth surface for further flooring work. This approach is also used in cases where the total thickness necessary screed reaches too large sizes, and it is more expedient to do it in layers.

Screeds also differ in the degree of adhesion to the base:

— Bound ties have direct contact with the base. Of course, with such a filling technology, maximum homogeneity of the materials and their high adhesion to each other must be ensured. Such coatings are characterized by good strength qualities in terms of withstanding high mechanical loads. However, the condition of the surface layer will largely depend on the moisture level of the base. Such screeds are mainly performed on dry floor slabs on the floors of buildings.

— In the case where the base does not have sufficient waterproofing, a sleep screed is used separation layer. A layer of waterproofing material (roofing felt, polymer film, coating composition) becomes a barrier to the penetration of moisture from below, and the screed itself has no contact with the base. With this technology, the layer of poured mortar cannot be less than 30 mm and, as a rule, requires reinforcement.

This technology is often used when constructing screeds on the ground, for example, in garages, sheds, basements, and on the first floors of houses without basements. They also use it in rooms with high humidity levels.

— Where enhanced thermal insulation of the floor is required or there is a need for sound insulation, floating screeds are used. In this case, the concrete solution is poured over a layer of insulation of one type or another. The screed turns into completely independent design- a slab that is not connected either to the base or to the walls of the room. The minimum thickness of the fill in this case is at least 50 mm, and reinforcement of the screed becomes a prerequisite.

The humidity of such a screed is absolutely independent of the condition of the base, and a good insulating effect is achieved. Disadvantages - excessively large thickness, and therefore - load on the floor. Typically, such screeds are used only on the first floors of residential or ancillary buildings, especially if the filling is carried out on the ground.

Screeds can be made with a homogeneous solution or include certain fillers:

— The addition of a cement-sand solution of polystyrene foam chips significantly increases the thermal insulation qualities of the coating.

Typically, such screeds require a second, strengthening and leveling layer.

— Where screeds of great thickness or with increased thermal insulation qualities are required, expanded clay is added to the concrete solution.

Expanded clay concrete has sufficient strength, but for laying some coatings, you will also need to fill in the front layer from ordinary mortar. And here ceramic tiles It will be quite possible to lay directly on such a base.

Screeds with micro-reinforcement show good performance fiberglass. This technology allows you to dramatically increase the strength of the coating to mechanical loads, stretching, and bending.

Such screeds usually do not crack, are less susceptible to shrinkage during hardening, and have less dust formation. They are great for underfloor heating systems.

flooring can be done using classic, “wet” technology, or using semi-dry technology. Semi-dry screed is a relatively new thing, and not all more ready to try it out in practice. In addition, it requires special professionalism in preparation. mortar mixture, in laying out, compacting and leveling the mortar. Most home builders prefer to use proven “wet” technology, which will be discussed later in the article. However, if you are limited in time, consider inviting a semi-dry screed installation specialist. When choosing a contractor, pay attention to the technology used - the presence of a mechanized supply of the composition will ensure cleanliness in the apartment. For example, laying a semi-dry screed along latest technology is carried out by the company "EUROSTROY 21 CENTURY" (company website www.prestigehouse.ru).

Solutions for pouring concrete screed

It is quite natural that if you need to pour a concrete screed, you will first need to decide on the type of solution. There are some options in this matter.

According to the existing canons of SNiP, the minimum strength of a conventional concrete screed, regardless of the type of further cladding, must be at least M-150 (the coating can withstand a force of 150 kg/cm²). If used self-leveling jellied composition, then here the requirements are even higher - from M-200. The solution should be selected in accordance with these requirements.

1. The “classic” concrete mortar used for pouring a regular floor screed is considered to be a cement-sand mixture in a ratio of 1:3. This “recipe” is time-tested and fully justifies itself. However, there are several nuances, without taking into account which you can easily ruin the future screed:

To prepare concrete, you cannot use ordinary “washed” river sand that has not undergone special treatment. Frozen surface will not be durable and will begin to crumble, crumble and crack over time. The fact is that grains of sand have smoothed outlines due to prolonged exposure to water, not providing adequate clutch. In this regard, quarry sand is much better than its faceted grains of irregular shape. True, when choosing, you need to look carefully so that it does not contain a large number of clay inclusions - this will also reduce the strength of the screed.

Availability small quantity The gravel component of the fine fraction will not affect the strength properties of the screed. However, if a smooth surface is required, it will be necessary to sift the sand through a sieve.

A very important condition for the strength and durability of the screed being poured is the optimally selected amount of water. It is no secret that some novice home builders, in an effort to make the work of pouring and leveling concrete easier, use excessive amounts of water, getting semi-liquid, easy spreading solution. By doing this, they are laying a “time bomb” - at the end, the screed will not have the required qualities.

Firstly, an excessively liquid solution will definitely cause severe shrinkage when hardening. In this case, one cannot expect a flat surface in accordance with the set level. And secondly, a violation of the cement-water balance will certainly reduce the strength qualities of hardened concrete. The surface is loose, unbound, with increased dust formation.

There are, of course, special amounts of water in concrete mortar, but they are usually adhered to by the technologists of production enterprises. reinforced concrete structures and large mortar units. In home construction, they often rely on own experience, intuition and common sense. In addition, it is very difficult to accurately calculate the amount of water due to the fact that it largely depends on the moisture content of the filler. The sand can be wet and heavy - and this is also water, which will participate in the process of preparing the solution.

Ideally, the concrete solution should be dense, but sufficiently plastic, so that when it is poured and leveled, there are no air voids left in the thickness of the floor. You can roughly focus on the following ratio - a liter of water per five kilograms of cement-sand dry mixture.

It is important to choose the right “golden mean” so that the solution is both dense and plastic

It is very difficult to mix the screed solution by hand using a shovel. It is better to use a concrete mixer or construction mixer of sufficiently high power for this. First, mix the dry ingredients in the required ratio (maybe with a little moisture), and then add water very carefully, portionwise.

An important condition for the quality of the future concrete screed is the purity of water. It is prohibited to use process water containing fats, oils, petroleum product residues, etc. Also, dirty, oily containers should not be used to carry water to the concrete mixing site.

2. The modern range of building materials on sale can significantly simplify the process of pouring screed. For these purposes, ready-made dry construction mixtures can be used.

Compared to using the usual cement-sand mixture, this technology has a number of advantages:

According to strength and other operational indicators ties made from ready-made mixtures, are in no way inferior to ordinary concrete, and can even surpass it in a number of parameters.
To prepare the solution you do not need powerful equipment or heavy manual labor– a mixer or even a powerful electric drill (hammer) with an appropriate attachment is enough.
In principle, there are no problems with the dosage of components - everything is already provided by the manufacturer, and the master can only strictly follow the instructions for preparing the solution.
Many solutions prepared from such mixtures are much lighter, which reduces the load on the floor, reduces transportation costs and makes it easier to lift materials to floors.

It is possible to select the desired composition for specific operating conditions. Thus, there are solutions for rough or leveling screeds, for underfloor heating systems and for rooms with high humidity. Special plasticizers or microfibers added to their composition not only increase the strength characteristics of the coating, but also reduce the time it takes for the screed to completely harden, reducing the overall duration of construction work.
What is very important for beginners is that working with such compositions is simple and does not require particularly high skills. The main thing is to follow the recommendations for pouring technology, which are necessarily attached to any batch of material.

All this will be true only if a high-quality dry mixture is purchased. Alas, there are a lot of fakes or low-quality mixtures on the building materials market in this segment. It is best to choose formulations from reputable manufacturers, be sure to check the certificate so as not to run into counterfeit products. It is also important to check the shelf life of the material - it is limited, and an expired mixture can significantly lose its quality.

The only drawback of this approach to pouring screed is that the price may be slightly higher than with self-production solution. Well, you have to pay for convenience and quality.

Prices for various types of screeds and self-leveling floors

Screeds and self-leveling floors

Preparing the surface for pouring concrete screed

The surface for pouring the screed is prepared in different ways, based on the conditions:

If the floor will be laid on the ground, for example, in a private house without a basement or basement, then the work is carried out in next sequence:

— The soil is selected to a depth of 500 mm.

A sand cushion 100 mm thick is poured and carefully compacted. A gravel layer is poured on top of it in the same way.

— Rough pouring of concrete with the addition of expanded clay is done to a height of 150 — 200 mm – for insulating the floor surface.

— After the base has hardened, it must waterproofed– roofing felt or dense plastic film to prevent the entry of ground moisture from below. Waterproofing material must definitely go out on the walls on height, slightly greater than the height of the planned screed. If necessary, another layer of insulation can be poured on top, and then a reinforced finishing screed can be poured.

In apartments, first of all, it is necessary to remove the old screed. This is done for several reasons:

— Firstly, the old screed does not guarantee integrity, since it can peel off, crack, and these deformations will be transferred to the newly poured layer.

— Secondly, do not forget about the maximum permissible loads on floor slabs. So, in serial high-rise buildings old building permissible load of about 400 kg per square meter - static and 150 kg - dynamic. And the news is one square meter concrete screed, 50 mm thick, approaches 100 kg. Therefore, all work related to thickening the screed will have to be coordinated with design organizations. And it is far from a fact that such permission will be obtained.

- And thirdly, the height of the ceilings in apartments is usually not so significant that you can afford to significantly raise the floor level.

The old screed is dismantled with a hammer drill, but very carefully to prevent destruction or damage to the floor slab. The remains of the chipped concrete are removed, and then the surface is thoroughly cleaned and dust-free.

If a bonded screed is planned, then it is necessary to thoroughly clean the existing recesses, cut cracks or crevices to a width of at least 5 mm so that the concrete solution can freely penetrate into them when pouring.
If the screed is floating or on a separating layer, then all defects must be repaired immediately. Do not leave voids under the waterproofing layer - condensation can accumulate there, and these areas high humidity, it is likely that they will become a “problem area”.

Defects are sealed using a repair compound, epoxy putty or ordinary concrete mortar. In case of large defects, polyurethane foam can sometimes be used.

The corners between the walls and the floor are especially carefully checked and repaired - water from the concrete solution when pouring the screed can penetrate deep into the ceiling or even leak to the neighbors below.

Then, in any case, the surface of the ceiling should be treated with a penetrating primer. This measure will additionally remove dust from the surface of the slab and improve its adhesion to the concrete being poured. In addition, the ceiling will not actively absorb moisture from the solution. This is extremely important. A lack of water in the layer of wet concrete adjacent to the base will lead to incomplete maturation of the cement stone, and the screed will peel off or collapse under even minor loads.

The soil is poured over the surface in strips and distributed evenly with a roller. In hard-to-reach places, for example in corners, it is better to use a brush.

Elastic is glued along the perimeter of the walls. damper tape. It will become a compensator for the expansion of the concrete screed, which will prevent its deformation or cracking. In addition, under no circumstances should the screed come into contact with vertical structures, be it walls, partitions or columns.

If the screed is on a separating layer, then first the entire surface of the ceiling is covered with a dense polyethylene film, at least 0.2 mm thick. The strips are overlapped by at least 100 mm. The joints must be taped with waterproof construction tape. You need to try to very carefully lay the film in the corners so that strong wrinkles and folds do not form - air “pockets” may remain there. The edges of the film on the walls should be 5 ÷ 10 mm higher than the planned screed - it will be easy to trim them later.

Schematic - waterproofing film and damper tape for screed on the separating layer

After the polyethylene is laid, the damper tape is glued - just as mentioned above.

Beacon system and reinforcement

To achieve horizontal screed and its required height, it is necessary to create a system of beacons along which the concrete mortar will be leveled.

Definition of zero level

It is very successful if the farm has it or if it is possible to take it from friends. In this case, the work will be significantly simplified - it will be much easier to cut horizontal stripes on the walls and control the level of alignment of the guides.

If this is not possible, then you can set up beacons just as well using a water level and a regular building level.

The water level consists of two cylindrical transparent vessels with the same scale applied, connected by a long elastic thin hose. According to the physical law of communicating vessels, the liquid level in them is always at the same height from the horizon. Thus, having made one mark at a certain level, you can high precision transfer it to other surfaces within the length of the flexible hose.

Marking begins by determining the zero level of the future screed. To do this, first of all, you need to draw a basic horizontal line. This is done as follows:

The estimated highest corner of the room is visually determined. A mark is made on the wall in this corner at an arbitrary height. It is better, of course, to make it so that it is as convenient as possible to work, for example, one and a half meters from the floor.

Using a water level, this mark is transferred to all walls of the room. The distance between the risks should allow you to connect them with a line using an existing ruler (you can use a long building level or a pure rule).
The drawn line should run along the entire perimeter of the room and close at one point - this will indicate the correctness of the measurements.
Measurements are taken from the applied baseline to the floor surface. Measurement points are usually every 0, 5 m. It is imperative to ensure that the measurement is carried out strictly vertically. The obtained values need to be written down (on a piece of paper or even on the wall with a pencil).

The measurement point that gives the minimum height of this distance will correspond to the highest section of the base.

From the obtained value in the most high point the thickness of the future screed is subtracted (minimum 30 mm). For example, the minimum height is 1420 mm. We subtract the thickness of the screed (30 mm) and get 1390 mm. This is the distance from the drawn reference line to the zero level.
Now it will not be difficult to draw the entire zero level line around the perimeter of the room - to do this, you need to measure the resulting value from the base down, mark the points and connect them with a straight line. To simplify your work, you can make a template and quickly move the marks from the base line. After connecting them, you get the main line of the zero level.
In construction practice, it is rare, but it still happens, when in the center of the room the floor level is slightly higher than at the walls. This must be checked by pulling the cord at the zero level between opposite walls and measuring the height from it to the floor. A similar check should be carried out in several places. If it is determined that there is a hill in the center, it will be necessary to shift the zero level upward to ensure the minimum permissible thickness of the screed over the entire area of the room.

Marking for beacon system

It is advisable to mark the beacons and guides immediately after hitting the zero level, guided by the following principles:

The orientation of the guides should correspond to the intended direction of the most convenient pouring of the screed. This is usually done along the room, from the far wall to the exit.
It happens that due to the complexity of the room configuration, it will be necessary to change the direction of pouring in a certain area. This should also be immediately taken into account when marking beacon lines.
The distance between the wall and the parallel guide closest to it is usually maintained no more than 250 - 300 mm. If you leave it large, a poorly leveled area or even a failure may form along the wall, which will require additional intervention later.

The distances between adjacent guides are not particularly regulated. The main thing is that the leveling rule installed on them protrudes on both sides by about 200 mm. The guides should not be spaced too far apart - quite large gaps may appear in the center between them after the hardening concrete shrinks.
I distribute the guide lines across the width of the room, usually at the same distance from one another.

How to set beacons and zero level guides

Previously, various available materials were used as guides for the beacon system, for example, wooden blocks or unnecessary pipes. Today, metal profiles are mainly used for these purposes.

Thus, galvanized U-shaped profiles from plasterboard systems perform very well. They are resistant to deflections and create a reliable “rail” for working as a rule.
Plaster profiles are very popular, although they are not without some disadvantages. They have a stiffener, however, on long sections when working as a rule, they can still sag. Therefore, when using them, the number of support points must be increased.
In some cases, you can do without using profiles altogether.

There are many ways to install a beacon, and it is impossible to consider everything. Let's look at just a few of them.

One of the most accurate and simplest is using self-tapping screws.

— At the far end of the room, at a distance of 250 - 300 mm from the corner between opposite walls, a strong cord (for example, a fishing line or a thick nylon thread) is pulled strictly at the zero level. It is important to tighten it as much as possible so that there is no sagging in the center.

- At the intersection of the line of the extended cord with the line closest to the wall, directing in the floor is drilled a hole into which a plastic dowel is driven and a self-tapping screw is screwed in. Using a screwdriver, it is screwed in so that the upper edge of its cap exactly coincides with the zero level.

— A similar operation is repeated on the opposite side of the room, closest to the exit.

— Two self-tapping screws defining the guide line are connected to each other with a tightly stretched cord, so that it runs along the top of their heads.

— On this segment, mark and drill holes for dowels, distributing them evenly so that an interval of 350 ÷ 400 mm is maintained between them.

— Self-tapping screws are screwed into dowels until their heads coincide with the tensioned cord. A check must be carried out using a building level - if necessary, the required adjustments can be made.

— In the same way, a line of screws is made on the opposite guide, and then on the intermediate ones. In this case, the check must be carried out in all directions - longitudinal, transverse and diagonal.

— Once the same zero level has been reached along all lines, the stretched cords are removed. Prepare a thick concrete solution. It is laid out in small slides along the line of screwed-in screws. Then a U-shaped profile is put on top and pressed into the solution. The transverse flange of the profile should rest against the head of the screw. It is important that the profile “sits” evenly on both sides, without distortions.

Installation and fixation metal profiles— guides

— After the solution has set and securely fixed the profiles in the installed position, you can proceed to pouring the screed.

With plaster profiles it turns out to be somewhat more complicated - it is more difficult to fix them using the heads of the screws. For these purposes, special fastening elements can be used - “eared”, which are placed on self-tapping screws, and their petals are used to crimp the side flanges of the profile.

Video: placing beacons using screws and fasteners -“ Ushastiki»

Another subtlety is that plaster profiles also have their own height, and this must also be taken into account when setting the screws to the zero level.

In addition, much more fixing solution will be required - to the point that I even resort to laying out a solid shaft into which the profile is embedded with emphasis on the screw heads.

Some craftsmen are accustomed to doing without metal profiles altogether.

— The exposed self-tapping beacons are tied with thin wire, thereby creating a kind of reinforcement frame. Then the solution is laid out along the entire line in a slightly excess quantity, so that the resulting shaft is slightly above the zero level.

— When the solution begins to set, a guide plane is formed. Using the rule, the upper edge of this shaft is compared and smoothed down to the screw heads.

- After hardening, you will get excellent guides along which you can work as a rule, and then they will enter the structure of the poured screed.

If the screed is carried out on the floor, then the self-tapping method becomes inapplicable - the tightness of the film cannot be broken, and in addition, there should be no rigid adhesion of the new screed to the base. In this case, you will have to tinker more, laying out piles of mortar and accurately inserting the guides at the zero level along the stretched cords.

To speed up the readiness of the beacon system, tile adhesive is often used instead of conventional mortar - its hardening time is much shorter. But gypsum compositions are unacceptable. Firstly, they practically do not shrink, unlike cement ones. Secondly, gypsum compositions have completely different indicators of water absorption, adhesion, strength, ductility, etc. We can say with 100% certainty that cracks will appear on the screed where the beacons are located.

Nuances of screed reinforcement

Of course, this measure is useful, especially with thick ties. Most often, a metal mesh made of galvanized steel wire with cells from 50 to 100 mm is used for this - it can be purchased ready-made in stores. Only when placing it, many people make a serious mistake.

If you look at numerous photographs on the Internet, you can see a mesh laid directly on the floor slab or on a layer of waterproofing. There are many doubts about the usefulness of such reinforcement. Ideally, for the reinforcing belt to play its role, it should be placed in the thickness of the mortar being poured, approximately in the middle of the height of the screed.

To do this, you can purchase special polymer stands. However, it won’t be difficult to make supports from wire or even raise the mesh onto linings from pieces broken tiles or fragments of old concrete screed. Wooden pads should not be used under any circumstances.

Obviously, it is necessary to install the reinforcing grid before setting the guides. Most often, the installation of the beacon system and reinforcement is carried out in parallel, and the mesh can also be fixed on those piles of cement into which metal profiles are embedded.

Filling the screed

Oddly enough, the process of pouring the screed itself looks, in the series of all technological operations, probably the most uncomplicated. If all the preparatory work is done correctly, then this stage will not be difficult.

For normal pouring and hardening of the screed, the optimal temperature is from 15 to 25 degrees. It is allowed to carry out work even with more low temperatures(but not lower than +5), but the maturation period of concrete will increase significantly. In too hot weather it is also better to refrain from pouring -= upper layer can quickly dry out and crack. Does not like screeds and drafts, although there is full access fresh air cannot be blocked.
It is best, of course, to work together - one is preparing the concrete solution, and the second is directly pouring and leveling the screed. The technology for mixing the solution has already been described above.
Work is carried out from the far corner of the room, gradually moving towards the exit. You should try to complete the pouring within one working day - this way the screed will be as uniform and durable as possible. If for some reason this is not possible, then the floor surface is divided in advance into sections (they are called fill maps) with jumpers installed between them.
spread in excess quantities between the guides, so that its layer is 15 - 20 mm above the zero level. Initial distribution is carried out using a trowel or shovel. It is imperative to ensure that there is no unfilled places- this happens often under the guides, under the bars fittings or at corners. It is necessary to achieve maximum compaction of the concrete solution and release of air bubbles from it. To do this, you can carry out “bayoneting” - the solution is pierced with a shovel or trowel before leveling.
Next, on on the rulers set the rule. Using forward and transverse zigzag movements, the solution is leveled to the level of the guides, so that a flat, smooth surface is obtained.

If the sand has not been sifted and large fragments (pebbles or shells) remain in it, then certain difficulties may arise - these inclusions can leave grooves and you will have to suffer a lot, removing them and smoothing out unevenness in order to bring the surface to an ideal state.

Concrete mortar added as needed so that the work goes on continuously. Excess mortar is carefully removed at the end of filling the room.

Video: a visual example of pouring screed along beacons

After the filling is completed, it is necessary provide measures, excluding accidental entry of people or pets into the premises during the first 5 - 7 days. In order for the maturation process to proceed effectively, the surface must be moistened daily (starting from the second day) with water, maintaining it during wet. In extreme heat, it makes sense to cover it with film after initial setting to avoid drying out.

If a regular one was used sand-cement mortar, then we can talk about the readiness of the screed with operational use no earlier than after 3 weeks. When using dry building mixtures, the timing may be different - they must be indicated in the attached instructions.

After the screed is ready, it is checked for evenness and surface quality. To do this, set a rule on the embedded guides and measure the resulting gap in the center. There is no escape from shrinkage of concrete, and if the gap does not exceed 1 - 2 mm, then this will be within normal limits.

Often a thin layer of compound is poured over the screed to make the surface perfectly smooth. However, this is a topic for separate consideration.

Before decorating the ceiling, its surface must be made perfectly flat. Only in this case the quality of work will be high. First of all, this condition must be observed for ceilings made of prefabricated reinforced concrete slabs, which are not always perfectly installed. Therefore, first we screed the ceiling, and only then move on to the decorative design.

Design features

The answer to the question of why a ceiling screed is needed is quite simple. Reinforced concrete slabs are massive floor elements that, even with the help of technology, are difficult to install on one level, therefore, as a rule, there are some differences between them. Their size depends on the quality of installation of the floor: the better the specialists and their work, the smaller the difference in the levels of the bottom of the slabs will be.

Alignment methods

Before you begin screeding the ceiling surface, you need to decide on the method you will use. There are two types of ceiling surface screed: “wet” and “dry”. The first method involves the use of solutions or mixtures. This could be a concrete ceiling screed made from cement mortar.

In addition, a large thickness of plaster can exceed the normalized load for which the ceiling was designed, which will also lead to negative consequences. To prevent all this from happening, you should use a dry screed. Of course, she also has her shortcomings. For example, this method “steals” quite a lot of height from the room, so already low rooms will become even lower.

Plastering the ceiling

Plaster is a hardened concrete mixture, the application process of which is quite labor-intensive, especially on the ceiling surface. But this method of screeding the ceiling does not lose its relevance, because sometimes it is the only way to create a flat surface. In addition, you can plaster any coating: wood, concrete or metal. But in any case, it is necessary to carry out preparatory work. They include several stages:

Cleaning the surface of contaminants, for example, mold or other fungal stains that need to be disinfected;
Removing old coating in the form of paint, whitewash, etc.;
Priming the concrete surface using strengthening mixtures;
For wooden and metal structures, the installation of reinforcing mesh is required.

Applying plaster on beacons