Floor materials, such as linoleum or ceramic tiles, require an absolutely even base. Surface imperfections and unevenness are usually detrimental to coating performance and durability. Therefore, many are interested in how to level the concrete floor.
How to level concrete floors
There are a lot of floor leveling technologies. However, all of them can be divided into two main groups:
- wet method, which includes the use of a cement-sand mortar or self-leveling mixture;
- dry - on logs, which involves the use of plywood, chipboard, etc.
When choosing how to level a concrete floor, consider:
- What condition is the floor in?
- maximum height difference of the base;
- type of decorative coating.
- Self-leveling floors will be the ideal solution when the floor surface has minor irregularities. The height difference should not exceed 3.5 cm.
- When leveling with a large layer of screed, the option of leveling by beacons is more suitable. This is the approximate height level of the new concrete base. It is also used if it is supposed to lay some communications through the floor and hide them under the leveling solution.
- Lag leveling is ideal for cold floors, in particular in your own home or the ground floor of an apartment building, since the space left between the floor and the slab is effectively used for thermal insulation. Through it, it is possible to carry out ventilation, drain, as well as other overall communications.
Substrate preparation for leveling
At the first stage, it is necessary to carry out preparatory work. A large rate of heat loss through the cement screed is the main disadvantage of this type of floor. Therefore, they first make insulation, and only then choose how to properly level the concrete floor.
The type of insulation is pre-selected and installed according to the technological scheme. To do this, you can use basalt wool, expanded polystyrene or expanded clay. However, the work does not end there. After pouring the subfloor and its final cooling, a number of defects form.
- Regardless of the technology chosen, the base must be thoroughly cleaned of the old coating, plinth and other, and, of course, of the resulting debris.
- Defects present on the old screed: tubercles, chips, depressions or other irregularities must be leveled. For pouring use a concrete mixture, various mastics or grout.
- As already noted, one of the important points in leveling a concrete base is the magnitude of the height difference, which is quite simple to calculate. The existing surface irregularities are determined using two levels: long and small.
- The floor surface is primed to increase the adhesion of the screed to the floor. This is especially true for the technology of self-leveling floors. Thus, it is possible to reduce the likelihood of cracks in the layer of the future screed, as well as to waterproof the floor. If the surface strongly absorbs moisture, it is advisable to repeat the priming procedure.
Preparation procedure:
- Crack removal. Visually determine their location. Then you need to expand them with a hammer and chisel. To fill the resulting cavity, you can use cement mortar or special building compounds;
- High bumps. It is recommended to remove them with a cutting tool - a hammer drill or an angle grinder. In the latter case, a concrete disc is needed;
- Pits. To remove them, you do not need to make a completely new screed. After processing the floor with a grinder, the resulting containers are covered with fine dry gravel. Then a solution of two-component epoxy concrete is prepared. The height of the repair screed is usually between 2 and 6 mm. The final drying time is about 50 minutes.
In this way, defects can be locally corrected. But how to level concrete floors if the level of height difference is significant? There are several effective ways to help solve this problem.
All work must be performed only after the final drying of the concrete screed. This process can take 20 to 60 days depending on its thickness and volume of water.
How to level the concrete floor in the apartment
With significant irregularities that exceed 10 mm per 1 r.m. it is recommended to make a new screed. But you need to be prepared that this process will take a long time. This method is used for leveling floors in utility rooms: garages, private boiler rooms, it is also possible to pour on the first floors of buildings.
We will analyze step by step how to level a concrete floor under linoleum, under a laminate and other popular floor coverings.
Cement-sand screed
Beacons are laid along the premises, which are metal slats, perforated corners or other similar material. In fact, they divide the floor into stripes. The distance between them depends on the area and configuration of the room. As a rule, the step is about 1 m. The DSP mixture is poured between the strips and “pulled apart”. Next, the solution is leveled using the rule. They move it in four directions: to the sides, towards themselves and away from themselves, relying on beacons. Each leveled section must be less than a meter long. It will take at least three days to dry such a floor.
The main disadvantage is the increase in the mass of the interfloor overlap. The weight of the screed is preliminarily calculated and the possibility of pouring it is checked. The technology is no different from the standard. Since it is necessary to level the concrete floor in the garage as correctly as possible, preparatory work is being carried out. The premises are completely vacated, the above-described preparatory work is being carried out.
Stages of execution.
- Setting the fill level. This is done using the building level. The best option is to use a laser tool.
- Installation of reinforcing mesh.
- With the help of a galvanized drywall profile, milestones are installed. They are fixed at the right height with a cement mixture.
- Preparation and pouring of the solution. It should evenly fill the entire volume, without going beyond the profile.
After completion of work, it is necessary to moisten the surface with water for 2-3 days. This will prevent cracks from appearing. The final drying time is usually around 25 days.
Self-levelling mortar
Not always the above method will be relevant. This is especially true for apartments where additional loads on interfloor floors are unacceptable. An alternative method is to pour self-levelling compounds. This is one of the modern ways to level the base for floor finishing materials. Leveling compounds are supplied as a dry powder. They may differ in composition: base, additives or fillers. It is important to choose the right type and composition. If the difference is more than 3 mm, you will need to use two types of mixtures. The rough surface will be formed first, which will eliminate obvious defects. The second, finishing, is intended for final processing. For this reason, the preparation of the mixture for use may vary and is carried out in full accordance with the instructions on the package. However, they are united by common points:
- The mixture is prepared immediately before use, as the solution dries up after about 30 minutes. For breeding, you need a container. Experienced craftsmen recommend a plastic bucket, since it is much more convenient to pour the mixture this way.
- The solution is poured under certain conditions. In particular, the door and windows in the room must be tightly closed to exclude possible drafts. The temperature regime, above 10 °, has some limitations, which must be maintained not only in the process of working with the mixture, but also when the self-leveling floor dries.
- If necessary, you can organize additional heating in the room.
- Although manufacturers claim that you can walk on the self-leveling floor in a couple of hours, however, practical experience shows that it will be more reliable to wait two to three days.
Manufacturers offer two main types of self-leveling compounds. Under a laminate or other coating, use the option for rough leveling. If we are talking about how to level the concrete floor in a garage or other similar premises, then they are additionally covered with a mixture for finishing leveling, on which paint, varnish and more can be applied.
How to level a concrete floor with expanded clay concrete, plywood without lag and other leveling methods
Another technology for leveling the subfloor is a dry screed, which simultaneously serves as thermal and sound insulation. This is ideal for surfaces with significant elevation changes. After preparing the base, polyethylene is spread over it and lag profiles are installed. Between the guides, granular material is poured, the excess of which is shifted in the direction of the exit.
Special sheets of Superpol are laid on the filling material, fixing them to the guides using self-tapping screws. The joints are sealed with tape.
Expanded clay floors
Using the same technology, the floor is leveled with expanded clay concrete. The difference lies in the composition of the solution. During its preparation, expanded clay of a fine fraction (up to 5 mm) is additionally added. As a result of this, the specific gravity decreases, since hollow components - expanded clay granules - will be present in the solution. At the same time, the pressure on the rough surface is reduced.
The disadvantage of this method is the low mechanical strength. It can only be used for private houses or apartments. If the critical pressure indicator is exceeded, local destruction of the floor will occur.
Expanded clay screed can be done in other ways:
- The entire surface of the base is covered with a layer of expanded clay with a height of 80–100 mm, leveled and poured with a layer of PCS.
- Expanded clay is scattered over the floor surface, leveled and watered with cement milk. They give time to “grab” and fill it with a sand-cement screed, which is then leveled.
- Initially, an expanded clay-sand-cement layer of the required thickness is laid on a concrete base. After about a day, the hardened layer is poured with a leveling PCS.
Attention
It is impossible to carry out filling at negative temperatures. Water crystallizes, which will lead to the destruction of the leveling layer.
Use of plywood
A feature of this method is the increased requirements for the base. The level of height difference should not exceed 1.5 cm. However, unlike the methods described above, plywood has several positive qualities.
The main one is a good level of thermal insulation. Together with the previously installed insulation, they will reduce heat losses in the room; plywood also has soundproofing properties. After its installation, the noise level in the room should decrease.
Before leveling the concrete floor with plywood without a log, it is necessary to select the appropriate material. It must have moisture resistance and sufficient mechanical strength.
To protect against moisture, the cement base is covered with a plastic film. The floor is dried first. Then you need to do the following.
- Prepare a plan for the layout of plywood sheets. According to the received plan, the purchase of material is carried out.
- Installation of sheets is carried out butt-butt. To seal the seams, you can use construction tape.
- Fastening to the base is done with dowels. Glue mounting is not recommended as cement flooring and plywood have different thermal expansion values.
After the final installation, it is necessary to check the level of the plane again. If the height difference remains the same, another leveling technology should be used. It consists in installing a log, on which sheets of plywood will be fixed in the future.
After installing the leveling coating, it is necessary to reduce the likelihood of moisture on the concrete surface. To do this, plywood panels should be sealed as much as possible.
In practice, there are many ways to level a concrete floor. But the above are the most effective and less time consuming.
Watch how to properly level a concrete floor video.
A flat floor in any room is necessary not only for aesthetic reasons, but also prevents injury to the owner of the property. The unpleasant appearance of a rickety cabinet cannot be compared with the overturning of a rocking TV or a broken limb as a result of a fall on "almost level ground." Whatever the cause: initial errors during construction or the appearance of potholes and cracks during operation, the question “How to level the floor?” sooner or later it gets up before new settlers, and during repairs.
In modern housing construction, the basis of the floor in a house, apartment, garage, office is concrete or concrete slabs. Depending on the purpose of the room, linoleum, ceramic or PVC tiles, parquet, laminate, carpet are laid on top, and the durability of the external, often expensive coating, depends on the evenness of the concrete floor base.
To obtain an even solid base for the floor finish, to achieve thermal, hydro and sound insulation, leveling is carried out either by screeding or by applying solutions of special mixtures for leveling the floor.
The choice of leveling method depends on the size of the floor height difference and the finished floor material: with a floor level difference of 3-4 cm, a leveling screed of the concrete floor is performed; if the floor is generally even, but a large number of cracks are found, then leveling is performed with self-spreading mixtures or tile adhesive.
Specialists distinguish between several types of screed, based on two main laying methods: dry screed and screed with the addition of various liquids.
Dry screed is easily performed even by a novice builder, it is cheaper and significantly insulates the room. Expanded clay, dry quartz sand, expanded polystyrene are used as a filler. Plywood, gypsum-fiber moisture-resistant sheets (GVL) or wood boards (chipboard, fiberboard) are laid on top, so a dry screed is made more often in living rooms.
The cleaned floor is impregnated with a primer solution that strengthens the concrete and increases its waterproofing properties. You can use "Betonkontakt". After drying, a layer of polyethylene (more than 50 microns) film is laid, joining the panels with an overlap of 18-20 cm and gluing them with adhesive tape. An overlap of 12-15 cm is left along the walls and glued with a damper tape.
In the absence of the necessary experience, it is advisable to lay U-shaped profiles turned upside down on the floor as beacons, setting them in level. Having filled a part of the filler into the formed cells, level it with a rule and lay sheets of the future floor, gluing the joints of the GVL with PVA glue and tightening it with self-tapping screws after 18-20 cm.
At the walls, the edge of the gypsum fiber sheets is cut off. You should not pay attention to the apparent instability of the first sheets; when they are spliced into a single monolith, they get a solid warm floor.
Thinking about the best way to level the floor, the majority tends to the classic version of the cement-sand screed, which gives a solid, even base for the finishing layer of the floor. The thickness of the future screed must be at least 3 cm, otherwise the strength is reduced significantly.
The concrete base is also cleaned, primed and dried. With the help of a conventional, water or laser level, beacons are installed, using a laser level, you can install beacons without assistants. Lighthouses are mainly installed with durable metal slats or T-shaped profiles, but pipes, edged boards or timber can be used.
The slats are installed on a thick solution, at a distance of no more than a meter from each other. The solution must be allowed to harden, otherwise, when leveling the screed, you can move the beacons and all the work will go down the drain.
Subsequent work does not require experience, but patience: pouring out the solution sequentially from the far corner, the floor is carefully leveled with a rule, moving it not only along the rails, but also making hand movements in a circle. In this case, the solution moves to the right and left, compacting and filling the voids.
To prepare the solution, cement of the M500 brand is most often used, adding three parts of sifted sand and water to one part of it (about 1 liter per 1 kg of cement). You can also use ready-made leveling compounds for the floor, commercially available: M150, M200, M400. The higher the number in the name of the mixture, the stronger the resulting coating. Prepare solutions in accordance with the instructions on the bag.
On the next day after laying, the screed must be lightly moistened with a roller, on the second day it is re-moistened and the strength of the solution is checked. If it is already possible to walk on it, the beacons are carefully pulled out and all the voids formed are rubbed with a fresh solution.
The screed is covered with a plastic film and, periodically moistening over the next week, is kept until hardened for at least 2 weeks, and preferably a month.
Along with strength and relative cheapness, the leveling floor screed takes a lot of time, which modern self-leveling mixtures, often called self-leveling floors or leveling mixtures, lack. The top coating can be installed after 10-12 hours, and the fully self-leveling floor acquires its characteristics within 12-14 days.
Such mixtures can be used with a height difference of not more than 3 cm, guided by the instructions attached to the bags with mixtures, since the further strength of the coating is more dependent on the chemical filler of the mixture. Deep (more than 6 mm) cracks and depressions must first be repaired with mortar and dried.
A leveling mixture diluted according to the instructions is poured onto the cleaned and primed concrete and leveled with a metal spatula. After that, the self-leveling floor is rolled with a spiked roller, removing the smallest air bubbles that reduce the strength of the floor.
It is necessary to do the work together, as the mixture sets in about 10 minutes. If it is necessary to slow down the rate of solidification, the floor is preliminarily slightly moistened with cold water, which also avoids cracking of self-leveling floors.
The small thickness of the finished floor allows it to be widely used in rooms with low ceilings. Along with the high cost, the negative characteristics of self-leveling mixtures include brittleness and low resistance to low temperatures of epoxy mixtures; mixtures based on polyurethanes are not resistant to chemical attack; methyl methacrylic are slightly resistant to abrasives.
Sometimes small cracks or irregularities are found in the floor, in this case it is possible to level the floor with tile adhesive, given that, for example, Ceresit can crack already at a thickness of 3 mm. It is undesirable to use full leveling of the floor with tile adhesive, replacing the self-leveling floor with it, despite the cheapness of the glue.
When deciding for yourself how or with what mixture to level the floor, it is necessary to take into account the temperature and humidity of the room, the level difference and the slope of the concrete base, the expected loads during the operation of the floor, labor and financial costs.
In this article I want to tell you and show you how to level the concrete floor quickly, efficiently and without large financial costs in almost any room. And all this can be done independently by anyone.
Preparation of concrete surface and materials
Our floor looked like this
Let's start to bring it into something suitable for . (or other coverage of your choice).
The floor is pre-cleaned of dust and dirt. Large chips, cracks putty. We treat the entire surface of the concrete floor with a deep penetration primer. 24 hours after priming, you can start leveling the concrete floor. It is recommended to glue the bottom of the walls with a special tape, but this is not necessary.
To level the existing one, we will use the self-spreading mixture "Osnovit T-45 Skorline" fast-hardening.
Is issued in packing on 20 kg. The cost of one package is approximately 250 rubles. In order to level the concrete floor, we needed to level and raise the floor by about 1 cm. The area of the room is 12 square meters. The consumption of this mixture is small compared to other manufacturers - 13 kilograms of the mixture per 1 square meter, with a layer of 1 cm. To level the concrete base, in our case, 156 kg of the mixture will be needed, respectively, these are 8 bags. Just in case, we bought another bag of mixture, but it did not come in handy. At a cost of 250 rubles per bag, we will spend 2,000 rubles on a room. Agree, it's not much.
In addition, we need a needle roller with a long handle. Its cost is about 250 rubles.
Drill with a nozzle (nozzle 250 rubles) for mixing the solution.
And containers for preparing the solution. We bought 2 containers of 20 liters worth 130 rubles each. We will also need the so-called paint studs. But, since there were none in the nearest stores, I made them with my own hands. To do this, you will need two planks the length and width of your foot, self-tapping screws - 12 pcs. for each and ordinary tape. We screw the self-tapping screws into the plank, when needed, we fasten it with adhesive tape to the legs. The main thing is not to do this ahead of time, so as not to spoil it in other rooms.
Concrete floor leveling procedure
So let's get started. You need to prepare the water in advance, as the mixture begins to thicken quite quickly. Water consumption 7 liters per 1 bag.
For work, you will need at least 2 people, it is difficult to do it alone. In order to level the concrete floor, carefully pour the contents of one bag into a bucket of clean water at the rate of 1 kilogram of dry mix per 350-370 ml of clean water (7 liters of water per 1 bag). At the same time, stir the mixture with a mixer.
Mix until a homogeneous mass is formed. We are waiting for 1-2 minutes.
At this time, pour the second bag into another container and mix, allowing the solution in the first container to settle. After 2-3 minutes, mix the solution in the first container again, and if there are no lumps, the solution is ready for use.
It is advisable to use the solution within 40 minutes. In this case, be sure to stir immediately before use.
While one person prepares the concrete floor, the second pours the finished one onto the floor, starting at the far end of the room, shod with paint shoes so that he can walk on the poured mortar without leaving marks. Each portion of the poured solution must be rolled with a spiked roller for better spreading and removal of possible air bubbles. And so we do with the whole quantity.
The whole filling took us 40-50 minutes. When the entire area of \u200b\u200bthe room is flooded, we still roll it several times with a needle roller. Removing air bubbles from the mixture to prevent further cracking of the floor. This mixture is good because you can walk on it after 2!!! hours. And the thickness of the mixture is from 2mm to 100mm.
If the room is very hot, after 2-3 hours you need to cover the entire area of \u200b\u200bthe room with plastic wrap. This procedure is necessary in order to protect the surface from drying out too quickly. If this is not done, then cracks may form.
Final works
After we have leveled the concrete floor:
ceramic tiles can be laid after 3 days.
Parquet, laminate, carpet, linoleum, cork after 7 days.
The final mixture dries after 28 days. So our . This is what it looks like a few minutes after the end of the pour. Almost like a mirror.
And this is what it looks like 2 hours later.
You can already walk on it. Especially true for walk-through rooms,. Total room 12 sq. m. we spent about 3000 rubles and 2 hours of our time. Economical and very high quality.
In some places, small tubercles turned out. This is a consequence of the fact that the roller was rolled poorly. But this defect is easy to remove with coarse sandpaper or a stone.
The technical characteristics of concrete floors must meet the requirements of SNiP 2.03.13-88 and the recommendations of the manual in the development of existing rules and regulations. Unfortunately, not all builders perform their work with high quality; during the laying of the finish coating, you have to deal with the correction of the admitted marriage.
Concrete floors can be leveled with self-levelling mortars, cement mortar screeds or ceramic tile adhesives. Under linoleum and carpet, the leveling of concrete floors is considered a mandatory operation; under ceramic or stone tiles, the decision is made based on the actual state of the supporting base. All floors installed on logs can be laid without prior leveling of concrete bases.
In the article we will consider several examples of leveling using various materials, taking into account the actual condition of the floors.
The composition of modern materials for leveling concrete floors includes several components, along with high mechanical strength of the mixture, they have good spreadability, ease of use, low shrinkage, resistance to various chemical compounds, manufacturability and relatively low cost.
Most of the existing brands meet the requirements of consumers, during the selection, the main attention should be paid to the following factors:
- which floor should be leveled. There are options for in-situ concrete, industrial reinforced concrete slab, base cement screed, self-leveling floor, underfloor heating system, etc.;
- fill thickness. Depends on the maximum roughness values and the type of alignment. Alignment can be preliminary or final. There are no strict requirements for the horizontal surface to the preliminary, it is used for finishing floor coverings along the logs. During installation, the position of the lag is controlled, if necessary, with the help of wedges or other linings, they are aligned;
- floor finish type. The softer the flooring, the more accurate and stronger the alignment should be, the better the material should be purchased.
After all the questions have been answered, you can begin work on leveling the concrete floor. To perform the work, you will need a suitable self-leveling floor, a primer, a construction mixer for preparing the mixture, a mortar container, a powerful (preferably industrial) vacuum cleaner, needle and paint rollers, a wide stainless steel spatula, a laser or water level, dowels for beacons, damper tape, tape measure, ordinary bubble level or rule.
Step 1. Count the amount of materials. To do this, first find out the maximum difference in height of the concrete floor. When checking its status, you need to use a long level or rule. Apply tools around the perimeter of the room, in the center and diagonally, keep the level in a horizontal position. The clearance is determined by eye or with a tape measure. The more lines that are tested, the more accurate the final results.
The minimum thickness of the leveling layer should be within 2-3 mm, add the maximum height of the irregularities to this value. The thickness of the liquid screed should be 2–3 mm greater than the height of the maximum irregularities.
Practical advice. In order to save expensive material, it is recommended to cut down the highest ledges. Preliminary mechanical alignment saves 25-30% of the material.
Step 2 Foundation preparation. The branded strength of the material for the leveling layer should not exceed the strength of the concrete base by more than 50 kg/m2. You can check the strength of the base with an ordinary coin. Draw two perpendicular lines on the concrete with the edge of a coin at an angle of about 30 ° to the surface, if the lines are even and without chips, then the base has sufficient strength for leveling work. The presence of a deep furrow, the appearance of chips at the intersection of the lines indicates that the strength of the base does not meet current standards. In this case, it is impossible to simply level the concrete floor, it is necessary to fill in one more layer according to SNiP. If the floor height does not allow this, then the old layer will have to be completely removed. It is very long and expensive.
Why is foundation strength so important? If the leveling layer is much stronger, then during shrinkage it will tear the weak base, the filling will peel off. There is a way out - to do the alignment with a weak solution. But it can only be used under hard topcoats, this option cannot be used for soft ones.
Removing the old screed is the best solution
Step 3 Clean the concrete floor. You need to remove dust, dirt, all loose elements of the concrete floor. Remember that the cleaner the base, the higher the adhesion of the leveling layer.
Step 4 Seal large gaps a day before leveling. Clean them from the remnants of old material, remove dust and moisten a little. Cracks can be sealed with the same mortar that is used to level the concrete. Clog them tightly, do not leave air pockets. You can level with a trowel or a small spatula.
Step 5 Prime the surface. The primer should be for concrete surfaces only. Due to it, not only the adhesion of the two materials improves, but also the indicators of hydroprotection improve, which is very important for floors in residential premises. It is necessary to prime with a roller, in hard-to-reach places use a paint brush. If the primer is absorbed very quickly, then the operation will have to be repeated. The second layer of primer is applied only after the first has completely dried, the time depends on the brand of material, temperature and humidity in the room.
Step 6 Glue foam polyethylene damper tape around the perimeter of walls, columns, interior partitions. It compensates for thermal expansion, prevents swelling and cracking of the leveling layer.
Important. If the room has a large area, then shrinkage seams should be made. They are located at a distance of about three meters, the lines should be parallel, at the intersection the angle is only a straight line. Damper joints can be made in advance using metal profiles or cut through the next day after pouring the solution. Remember that the second option is accompanied by a lot of noise and dust.
Step 7 Find the horizon level on the wall. It is much easier and faster to do this with a laser level, if you don’t have one, then use a water level. Set the laser level in the center of the room, bring a horizontal beam to the walls. Using a tape measure, mark at the desired height from the concrete floor surface.
Step 8 Screw self-tapping screws into the concrete floor to control the height of the leveling layer. Beacons should be in the corners and along the lines of the room, the step between the rows is approximately one meter. First, fix the dowels against the walls, the height is set according to the marks. Then, between the extreme opposites, pull the rope and install all the other dowels along it. If you do not have strict requirements for the horizontal fill, then you can not install beacons.
Step 9 Prepare a solution. The proportions are indicated by the manufacturer on the packaging, follow his recommendations. Water is always poured into the container first, and then the dry mixture is added. It is advisable to pour the mixture with the mixer on, this will help minimize the number of lumps and allow you to constantly control the consistency of the solution. Mix the material thoroughly and leave it for 5-10 minutes. for insistence. During this time, all the smallest lumps of cement are completely saturated with water. At the same time, chemical curing reactions are started. After infusion, stir the mixture again a little.
Important. Do not allow an overdose of water, this significantly reduces the strength indicators. One more thing. Accurately calculate the volume of the solution with your performance, consider the recommended use time. Keep in mind that once the solidification process has begun, it is impossible to stop it, and adding water to the thickened mass only exacerbates the situation. On average, a freshly prepared mixture should be used within half an hour.
Step 10 Start pouring the solution. Start pouring from the far wall of the room and move towards the exit. Pour the solution from a height of 20-30 cm, avoid large splashes. Move the bucket in a zigzag manner, do not leave large gaps. The width of the strip is approximately 40 cm, you should easily level it with a spatula. Each subsequent portion of the material should overlap the previous one by about five centimeters. Constantly monitor the marks on the wall and the markers from the dowels, if necessary, increase the thickness of the mass or disperse the excess over the free area.
Step 11 As the flooded area expands, roll it with a spiked roller. It removes air bubbles and improves the adhesion of the mass to the concrete base. The length of the needles of the roller should be several millimeters greater than the maximum thickness of the application of the solution. Keep this in mind when purchasing the instrument.
Practical advice. To increase the strength of the leveling layer, it is necessary to prevent direct sunlight from entering the room, close windows and doors to prevent drafts. If this is not done, then some areas will lose moisture much faster than is necessary for optimal conditions for chemical reactions to occur. In these places, the strength of the layer becomes significantly lower than expected.
After complete hardening, the floor surface can be covered with any soft coatings or pasted over with ceramic tiles. But it should be borne in mind that leveling with bulk materials according to the above technology will always have deviations from horizontal within ± 1.5–2 mm. Is it possible to level concrete floors with perfect precision? It is possible, but for this you should use a different technology for the production of work.
Prices for self-leveling floor compounds
self-levelling floor compounds
Alignment of the concrete floor on the lighthouses
This method takes a little longer, but guarantees a perfectly horizontal surface. The most difficult thing is the creation of lighthouses. For this process, we will give detailed instructions. For work, only a laser level is needed, ordinary water levels cannot achieve such a result.
From the tools you will need a large rule, wide and narrow spatulas, a trowel and a folding wooden meter. Roulette is not good, it is too soft.
Lighthouses can be made from any cement or gypsum mixtures, but we recommend using Fugenfüller putty. It has high physical strength, excellent adhesion to all mixtures made on the basis of cement with or without the addition of innovative fillers. In addition, the hardening time of the putty is approximately 30 minutes, which is quite enough for the manufacture of lighthouses at an average pace. After the preparation of the last lighthouse is completed, it is already possible to work on the first ones.
Another plus of the leveling beacons offered by us is that they make it possible to save building materials. The height of metal profiles is at least one centimeter, which means that the minimum thickness of the fill will be the same. The minimum height of our beacons is equal to the thickness of plastic crosses and is only a few millimeters. The difference in the volume of filling due to the height for large rooms is significant.
Step 1. Set the laser level, check the condition of the floor, determine the minimum thickness of the leveling layer. Remove construction debris from the surface, vacuum it.
Step 2 Prepare putty. Accurately observe the proportions indicated by the manufacturer, do not experiment, they will not lead to anything good.
Step 3. Start installing beacons against the wall, the rule will be used instead of a tape measure to measure the distances between the beacons. Lay out the first pile of putty at a distance of about 15-20 cm from the wall, trim it a little.
Install a plastic cross for ceramic tiles in the center.
Put a meter on it and, taking into account the location of the laser beam, drown it in the solution. Make sure that the cross is lying horizontally, check its position in several places.
Carefully remove excess putty. You can not clean up near the cross, it will then be cut off with a spatula. If you touch the unhardened putty, then you can violate the position of the cross, you will have to redo everything again.
Step 4 Lay a rule on the floor, the distance between the beacons should be 15–20 cm shorter than the length of the rule. In the same way, the width between the lines of beacons will be determined. Install all beacons in the room.
Step 5 After the point beacons have hardened, clean the surface of the crosses from putty, pay attention that it is even. Put the rule on two adjacent points on top, put the solution with a spatula into the gap formed between it and the concrete floor. From the first time it is difficult to guess the thickness, in the future practical experience will appear and the work will go much faster.
Step 6 Rule carefully align the surface of the shaft made. If there are unfilled places, then add a little putty to them and again level the surface with the rule. Remove excess mass immediately in a container, mix the mass periodically.
It is possible to level the floor only after the beacons have completely solidified. It is allowed to use a self-leveling floor mortar, a cement-sand mixture or an adhesive for ceramic tiles. Decide for yourself which one, but there are general recommendations.
- The cost is the cheapest cement-sand mortar. If you have large areas or a significant thickness of floor leveling, then it is better to use this material. Per cubic meter of solution, significant financial savings are obtained.
- In terms of physical strength, tile adhesive is in first place. But it is difficult to work with him, you need to have practical experience.
- Self-leveling floors serve as additional waterproofing, in some cases this property allows you to speed up construction work.
As for time, there is almost no difference. It is not necessary to believe that bulk materials can significantly reduce the time for leveling the floor. An experienced builder will make exactly the same footage with the help of beacons and rules.
Step 7 Pour the mass between the beacons, align it as a rule. The tool must be pulled towards you and at the same time perform small movements to the left and right in amplitude. There are gaps - add the solution and repeat the leveling.
Practical advice. For inexperienced builders, after leveling the rule, small waves may remain on the floor surface. This is not a problem, do not scrape off the frozen mass. It is much better, easier and faster to repeat the leveling of the floor in a direction perpendicular to the first one. No more beacons. Just pour a thin layer of the solution on the floor and, as a rule, pull off the excess, make the mass a little thinner. It will fill all the waves and perfectly level the floor.
Leveling a concrete floor with tile adhesive according to a simplified scheme
This method is great for ceramic tiles, the time of work is significantly reduced, and the quality completely satisfies the tilers. It is rather difficult to level the floor during tiling by changing the thickness of the adhesive; only highly professional tilers can do this. And even then, most of them prefer to level the concrete base on their own and lay tiles on the finished surface, especially if the height difference is 1 cm or more. The end result is time savings.
Step 1. Cut down large mounds, clean the surface from construction dust and debris. If the concrete is very dry, then it is recommended to moisten it with plenty of water. Water should not be immediately drawn out of the adhesive, it is needed for the optimal flow of chemical reactions. The lack of the required amount of liquid critically reduces the strength of the adhesive leveling layer.
Step 2 Prepare the tile adhesive. There is a caveat here, the glue should be a little thinner than the manufacturer recommends. It will be difficult to work with thick, in addition, in places with a small thickness, water is quickly absorbed by concrete, which causes a decrease in physical strength indicators. We have already mentioned this. The consistency of the solution should resemble ordinary sour cream or heavy cream and spread a little over the surface.
Step 3 Pour the adhesive in portions onto the floor surface and, as a rule, pull off the excess. The towering sections of concrete serve as beacons, the glue fills only the depressions.
Important. Before starting work, you need to determine in which direction to pull the tool. This can be done after a careful inspection of the concrete floor. You should find the beacons by which it flooded. Then use a bubble level or rule to find out the location of the recesses.
Professional builders during this alignment after the first screed make a few more additional diagonal or circular movements as a rule. At the same time, the pressing force is minimal, the quality of alignment largely depends on practical experience.
If after the first pass the height differences are still large, then draw the rule in a perpendicular direction to the first pass. Once again we warn you, on the second pass, reduce the pressing force. You do not need to achieve ideal performance, differences in height within ± 5 mm for laying tiles are not a problem.
In order to improve the adhesion of the adhesive to concrete, after pouring, it is recommended to carefully rub it into the floor with a spatula or trowel. The recesses found after stretching the rule must be immediately covered with glue and re-leveled. The work does not take much time, the only drawback is that tiles can only be laid the next day. But a professional builder does not waste time, there is always a small amount of previously deferred or preparatory work at the facility.
Video - Leveling the concrete floor with bulk mixtures
During the arrangement of the coating in the premises, as a rule, the question arises, how to level the concrete screed?
In modern construction, the main material for the floor is concrete or concrete slabs. Depending on the type of premises, the top layer can be linoleum, ceramic or PVC tiles, parquet or laminate flooring.
The service life of such a coating will directly depend on the evenness of the concrete base.
Work options
In order to level the floor and get a solid base for the front flooring, to provide heat and waterproofing, you can use the screed method or a special mixture (for leveling).
The leveling method will depend on the magnitude of the elevation changes and the material of the front deck. If the level difference is from 3 to 4 cm, then leveling is performed. If a large number of cracks are found on the floor, leveling is carried out using self-spreading mixtures or tile adhesive.
Professionals, in order to carry out alignment, use the main types of screed, which are based on two laying methods:
- dry screed;
- screed with liquids.
Dry screed
Dry screed, due to the ease of implementation, can be done by anyone. Another privilege of the device of this screed is a significant warming of the room at a relatively low cost. Expanded clay and quartz sand are used as a filler. Then plywood, gypsum-fiber moisture-resistant sheets or wood boards are laid on top. As a rule, dry leveling can be done in residential areas. The prepared floor is impregnated with a primer solution, which strengthens the concrete and increases its waterproofing function. After the floor dries, a layer of polyethylene film is laid, while the seams are overlapped by 20 cm and glued with adhesive tape. An overlap of 15 cm is left on the walls and glued with a damper tape.
Beacons are U-shaped profiles, which are laid on the floor, turning them upside down, they are set according to the level. The filler is poured into the resulting cells, leveled with the help of the “rule”, then the sheets are laid. The joints are glued with PVA glue and tightened with self-tapping screws in 20 cm increments. At the junction with the walls, the edge of the gypsum fiber sheets is cut off.
Cement-sand mixture
Most experts recommend the classic cement-sand screed option, which provides strength and leveling of the base for the front deck. The minimum thickness of such a screed should be 3 cm. If you make it thinner, you can drastically reduce strength. The concrete base is also cleaned, primed and dried. With the help of ordinary, water or laser levels, beacons are mounted. Beacons are metal rails or a T-shaped profile. In some cases, you can use pipes, edged boards or timber. The slats are laid on the liquid solution at a distance of no more than 1 m from each other. Allow the solution to dry. During the alignment of the screed, the beacons can be moved, and everything will have to be done in a new way.
The scheme of the cement-sand screed
The next job will require patience. Consistently, the solution is poured from the far corner, the floor is carefully leveled using the rule. They move it not only along the rails, but also make translational movements with their hands in a circle. As a result, the solution will move to the sides, compact and fill the voids.
For the mortar, in most cases, you can use cement grade M500 in a ratio of 3: 1 (approximately 1 liter of water per 1 kg of cement). Use of ready leveling mixes is possible. Their brands are M150, M200, M400. The higher the number in the name of the mixture, the higher the coating strength indicator will be. Such solutions are prepared in accordance with the instructions on the bag.
A day after laying the screed is slightly wetted with a roller, the next day it is re-moistened, the readiness of the solution is checked. If it will be possible to walk on it, then the beacons are carefully pulled out, and all the remaining voids are rubbed with a freshly prepared solution.
The screed is covered with a polyethylene film and periodically moistened throughout the next week, aged until fully compacted, but not less than 2 weeks, 1 month is optimally recommended.
Self-levelling mortars
Together with strength and relatively low cost, a leveling screed takes a lot of time, which cannot be said about a modern self-leveling mixture, more commonly called a self-leveling floor or leveling mixture. The top layer of the coating is installed after 12 hours, and the fully self-leveling floor reaches its condition in a maximum of 14 days.
It is possible to level the floor with this type of mixture in case of a height difference of no more than 3 cm, guided by the application that is on the bags with the mixture, since the future coating density directly depends on the chemical composition of the filler. Cracks with a depth of more than 6 mm are pre-sealed with mortar and dried.