Self-leveling floor on fiberboard. We make a floating concrete screed under the tiles on the wooden floor. Prices for self-leveling floors "Prospectors"

A screed on a wooden floor is not the best solution for a new floor. However, despite this opinion, if all technologies are followed, it is really feasible. In addition, there are wooden floor structures, which, being in good condition, are easier to fill with a self-leveling floor than to redo the entire floor structure.

This article will be useful for those who are building their own country house. Having made a self-leveling floor over a wooden one, it is easy to lay tiles in a bathroom or kitchen at home.

Information about septic tanks made of concrete rings will also be useful for owners of country houses. You can get information about septic tanks and make an order.

Wood floor constructions

Before starting a conversation about screed on a wooden floor, you need to understand about the structures of wooden, plank floors.

It hardly makes sense to make a screed on a wooden floor, which is laid on logs and a floor slab with a thickness of 220 mm. The thickness of such a wooden floor is 70-77 mm and the best solution for such a floor would be to remove the wooden floor together with the joists and make a screed over the concrete floor slab.

It makes sense to make a screed on a wooden floor if the floor joists are on high brick pillars. The height of such pillars can reach 30-40 cm (and more) and it is not possible to replace them with a screed. You can see two photos of schemes of such floors below.

It is precisely about floors of this design that we can talk about as a possible basis for a screed.

Features of screed on a wooden floor

Before deciding to make a screed on a wooden floor, pay attention to the following:

A screed on a wooden floor refers to unbound screeds, that is, the layer of such a screed will not be connected to the bottom layer of the base and will be isolated, unconnected to anything on the floor. Hence, some of the features of the screed on a wooden floor follow.

At first, the wooden base for the screed must be very strong and completely motionless. Damping, which is so characteristic of a wooden floor, must be completely eliminated. With a possible vibration of the wooden floor, the screed above it will crack, which is unacceptable.

Secondly, depending on the selected screed material, the screed thickness can be quite thick. For example, using a cement-sand mixture for a screed, the thickness of the screed should be from 10-12 cm. The weight of such a screed will significantly increase the load on the wooden floor. If we take into account that the wooden floor is laid on the logs, and there is a step between the logs (the distance between the logs), then when the load on the wooden floor increases, the distance between the logs must be reduced. In large rooms, the distance between the logs can reach 85 cm.Therefore, having decided to make a cement-sand screed in a large room, you have to disassemble the floor, reduce the step between the logs, put new logs and restore the wooden floor again.

It's still a job, and, perhaps, it is worth thinking a hundred times before making a cement-sand screed on a wooden floor in a large room.

In order not to disassemble the floor and not to reduce the distance between the logs, use not a cement-sand mixture, but for example, anhydrite floor leveling agents. The thickness of such a screed is from 30 mm, the leveler does not require reinforcement and can be used for loose screeds.

Thirdly, a cement-sand screed on a wooden floor is made, always with a reinforcing mesh. This is done, again, to increase the strength of the screed. Moreover, the fiber in the screed will not relieve you of the use of a reinforcing mesh. That is, for a semi-dry screed, you will also have to make a reinforcing mesh with cells of 100 × 100 mm.

Output. The use of a cement-sand screed for large rooms with a wooden floor is not justified by time-consuming work. But. If the circumstances and conditions are such that it is impossible to avoid screed on a wooden floor, then for the screed device it is better to take a leveler suitable for an independent screed, and not use a cement-sand mixture. And in general, I would not consider a cement-sand screed as a priority for screed on a wooden floor, although the use of a high-quality leveling agent will significantly increase the cost of the screed material.

Screed material for wooden floors

To perform a screed on a wooden floor, you will need the following material:

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Polyethylene film with a thickness of 200 microns, for waterproofing the screed layer from wood and walls;
Screed mixture. Read about the choice of a mixture just above. If you choose a cement-sand mixture, then prepare a reinforcing mesh, preferably with a stainless steel coating. The net should not be in rolls. Why not in rolls?

You have to fix the reinforcing mesh on a wooden base, while you must not break the waterproofing, that is, do not tear the film. Think about how you will attach the mesh. At the same time, think over how you will fix the beacons for the DSP screed, because there is nothing to attach the beacons to, the base for attaching the beacons is polyethylene.

Why am I making these notes. In my opinion, it is better not to do the device of a cement-sand screed on a wooden base in large rooms. The amount of work and problems will completely overshadow the result. Replace the DSP with the "Equalizer" for insulated bases (loose screed). For example, an anhydrite floor screed.

Wood screed technology

The wood floor must be strong, motionless, dry and not rotten. The same applies not only to the floorboards, but also to the logs and posts on which it is laid. Rotten boards need to be replaced.

Important! Do not screed on a freshly laid wooden floor, it may deform. The age of the screed wood floor must be more than one year when the floor is used in the domestic temperature range. Although I have no idea who needs to screed the new wooden floor.

The heads of nails with which the boards are nailed must be drowned a few millimeters so that they do not tear the layer of waterproofing film, which must be laid on top of the boards.

If your apartment is on the ground floor and there is a basement or ground below you, then the seams between the boards need to be putty with epoxy putty. Epoxy putty is chosen because it does not allow moisture to pass through. Seams are closed so that vapor does not form between the film laid under the screed and the boards.

If the joints between the wall and the floor are wide, then seal them up with construction foam, and on top with epoxy putty and liquid waterproofing.

After the putty dries, polyethylene 200 microns thick is spread on the wooden base. Polyethylene is spread over the walls with an overlap of 10-15 cm. Two adjacent pieces of polyethylene are laid with an overlap of 20-25 cm. Seal the joint between the pieces of polyethylene with non-soaking assembly tape. Use scotch tape to glue the gaps to the wall.

The polyethylene should lie flat, without wrinkles. There should be a clean wood base with no debris underneath the polyethylene.

Preparation of the solution

Let me remind you, we are making a screed from a mixture of roving. We make the screed solution according to the instructions on the package. The roving mixture is added to the water, not vice versa. The mixture is stirred to a state of thick sour cream mechanically, with a mixer at low speeds.

How to check the thickness of the mixture

To check if the mixture is thick enough, find a container with a diameter of 70 mm, so that it holds 1 liter of solution. From this cylinder, pour 1 liter of the solution onto a plexiglass plate 50 × 50 cm. The diameter of the spread solution should be 34-38 cm. This means that the thickness of the solution is correct. The thickness of the solution must be checked constantly.

Set the screed level

The unbound screed with a leveler must be more than 30 mm. For a wooden floor, choose 50 - 60 mm. It is better to measure the level of the screed with a laser level. If the room is very small, the building level is sufficient. At the level of the laser, draw a screed line along the wall and set the bench mark beacons (levels on the legs) along the floor surface.

Filling the screed

The ready-made leveling compound is poured continuously over the entire floor surface from the far corner to the outlet. For a successful fill, you will need helpers. One dilutes the mixture, the second continuously pours the solution, the third evens the solution according to the level of beacons and marks, with a special metal bar with oscillatory movements (raising and lowering the bar) along and across the cast surface.

Care of the filled screed

There should be no drafts and low temperatures in the room with a filled-in screed. If you nevertheless used a solution from DSP, then cover the screed with polyethylene. Anhydrite self-leveling floor must be protected from excessive insolation (direct sunlight), too high temperature, drafts and water for 2 days. After two days, the room needs to be ventilated.

Some conclusions of the article

Before screed, evaluate the structure of your wooden floor;
The cement-sand screed is very heavy and will put a heavy load on the wooden floor, therefore, you may need to reinforce the wooden floor;
If possible, replace the DSP with a high-quality leveling device for an independent screed;
DSP screed on a wooden floor is cost-effective only for small rooms, kitchens, baths;
Think a hundred times before applying a screed to a wooden floor in houses with wooden floors, be aware of the load.

And the last thing. If you plan to use tiles as finishing, replace the screed on the wooden floor, if possible at a level, by laying cement-bonded boards (DSP).

Wood floors, when used with the right materials and installed correctly, can maintain their durability and stability for decades. Sometimes the question arises of laying concrete screeds directly on such floors. Why is there such a need? They think about a concrete screed in cases where the floor is ideally aligned in order to lay some kind of coating on it (ceramic tiles, a layer of polymer materials). The same method is used when full wood flooring is prohibitively expensive.

What you need to know about wood floors

Wood, which has a lot of technological advantages, is also known for one significant drawback, which should be taken into account in the course of working with it. This drawback consists in the lack of its static nature: even after the completion of construction, wooden elements continue to "live" guided only by their own laws. Changes in humidity and temperature conditions cause:

increase or decrease in the volume of wooden parts and elements;
their shrinkage in height;
increase or decrease in their linear dimensions.

This feature of the tree has led to the rule that builders who are engaged in the construction of wooden structures are always guided by: the finishing of log cabins should be carried out no earlier than two years after their construction. With regard to our topic, this rule should be interpreted as follows:

It is strictly forbidden to pour concrete mortar on a new concrete floor. The concrete screed can only be laid 3-4 years after the completion of the floor installation.

The mobility of wooden floor structures increases when any heating systems are installed under them. Each start-up and shutdown of such a system will cause them to move slightly.

If we compare the mobility of wooden structures with the mobility of a concrete slab, which is formed when the screed is laid, it should be noted that the geometric dimensions of the latter change only during hydration. When the hardening of concrete ends, the dimensions of the monolith practically do not change. Such a difference in the behavior of wood and concrete, if they are in close contact, can cause cracks in the screed. Moreover, in such a case, it may even crumble completely.

The technology of leveling, performed without connection to the walls and with a wooden floor, which we will discuss below, allows each of the elements - floorboards and concrete screed - to exist, obeying only their own principles and without harming their neighbor.

Materials required to complete the work

If an assessment of the condition of the wooden floor and other related conditions led you to the conclusion that a concrete screed is really necessary and that it is quite possible to make it, it is necessary to prepare in advance the materials that will be required during the work.

When preparing, it must be remembered that the pouring mass must be sufficient to guarantee the tightness of the screed adhesion to the boards. However, the large weight of the concrete used can cause the floor to sink, bend, and then destroy the laid screed.

If the condition of the floor tells you that such a course of events is quite possible, when preparing the concrete mixture, you should use a plasticizer, which will give the concrete some mobility, while maintaining its integrity. An additional advantage of plasticizers is also that these substances can have a positive effect on increasing the waterproofing of the screed, which will provide additional protection for wooden structures.

And so, the list of materials required for laying the screed includes:

cement and the required amount of plasticizers;
the film necessary to separate the concrete from the surface of the wooden floor;
sand;
any suitable sealant;
epoxy or other suitable filler;
a primer with a water-repellent effect;
metal mesh for reinforcement.

During preparation, you need to make sure that there are no breaks on the purchased film. Since the film should be laid with an overlap, and its edges should slightly rise to the plane of the walls, when calculating its amount, at least 15% should be added to the area of the room.

It should also be remembered about the tools that will be needed during the work. In particular, you will need:

a spatula with which putty and sealant will be applied to the floor;
hammer and screwdriver to reinforce the floor with nails or self-tapping screws.

Surface preparation of wooden floors

A concrete screed can be applied to the floor only if its surface is completely ready for it. When preparing it, you should carefully examine each floorboard to make sure that they are free of rot and cracks. All boards must be securely fixed, there must be no gaps between them. Boards that are heavily damaged are removed and replaced with new ones. If it becomes necessary to break the floor, then the heads of the nails should be sunk. The resulting grooves must be carefully putty.

When preparing the floor surface, you must:

fill with putty and, if necessary, polyurethane foam all the gaps on the floor;
treat wooden elements with sealants;
after all the substances applied to the floor have dried, clean it of debris and treat it with a moisture-resistant primer;

when the primer is dry, roll out the film with an overlap, so that it goes on the plane of the walls by fifteen centimeters. Excess film must be trimmed. Fastening the film, if necessary, should be done with adhesive tape. The use of nails to fix it is unacceptable.... For best results, a reinforcing mesh can be laid over the foil.

In the video below, you can see how the film is correctly laid on the surface of a wooden floor:

Having completed all these operations, you should start drawing preparatory markings. One of the original markup methods is presented in the following video:

Directly on the film covering the floor, with the help of concrete, rack beacons are strengthened, the distance between which should not be greater than the dimensions of the rules used when leveling the concrete solution.

Concrete screed and the process of pouring it

Pouring is preceded by the production of a concrete mixture. For its preparation, clean sand and cement grade 400 are taken in a ratio of 3: 1. The solution is prepared on the basis of water with the addition of special plasticizers or similar substances. For mixing, you can use a large plastic container and a drill with a mixing attachment. After mixing the solution, it is necessary to let it settle, and then stir it again.

If the thickness of the screed does not exceed 1 cm, then the consumption of the concrete mixture will be about 15 kg / m 2. Pouring out the solution should be carried out, focusing on the beacons. The entire floor must be filled at the same time. Laying in pieces is not allowed. During the pouring process, air bubbles must be removed from the cement mortar using a needle roller. The leveling of the mixture poured onto the floor, so that the concrete screed is even, is carried out using a wide spatula or a rule.

The screed leveling techniques on wood and concrete floors are similar, so the following video can be used to learn more about the techniques used in this case:

The drying time of the laid screed is 28 days. During the first two days after installation, it should be moistened with water three times a day. After that, the beacons are removed, and the surface is primed and rubbed. After a month, the concrete screed is completely ready for full operation.

In the video below, although it is not in Russian, you can perfectly see all the schematic stages of laying a concrete screed on a wooden floor.

Nowadays, in repair work, mixtures prepared at the factory are increasingly used, which allow you to quickly and efficiently level floor coverings of any type. A self-leveling floor on a wooden base is one of the most popular flooring methods.

The main advantages are durability, wear resistance, strength and ease of installation. In addition, materials are available in a wide range, there are even options with a 3D image.

What to look for when choosing a material

First of all, you need to carefully examine the packaging. All manufacturers indicate what exactly this or that composition is suitable for. To make a self-leveling floor in a wooden house, you need to choose materials with appropriate marks, universal compositions are also suitable. But if it is indicated on the package that the solution is suitable for concrete or anhydrite screeds, then it cannot be used for wood.

When choosing a composition, you should pay attention to the purpose - only universal or special mixtures are suitable for a wooden base

It is important to remember that self-leveling wood floors are poured with a layer of 3 to 7 centimeters, so it is not advisable to buy expensive gypsum mixtures, which are designed for a layer of about 0.2–2.5 cm. The use of cement or gypsum-cement mortars is recommended. To determine the type, you need to read the composition. The first substance is the one that contains the most.

In addition to the material, it is necessary to purchase plastic wrap, which will serve as waterproofing. In rare cases, a coating waterproofing can be used instead of polyethylene. You will also need a damper tape.

Base requirements

It should be noted that self-leveling floors can not be applied to every surface. The foundation must meet the following requirements:

The floors should not squeak.
The boards are securely fixed and do not bend while walking.
The flooring has a slight blockage.
There are no serious defects on the surface: large cracks, holes, and so on.
Each board must be intact, free from traces of mold and mildew.

It is not necessary that the base be even, the main thing is the good quality of the board, the absence of squeak and solidity

If any of the listed defects are found, you will have to replace part of the floor or the entire surface.

Preparatory work

Self-leveling floors can only be laid on a wooden floor if the base is well prepared. It is from this stage that the duration of use of the coating, its appearance and performance depends.

Immediately before starting work, check the air temperature and humidity level. The required parameters are indicated by the manufacturer on the packaging. Compliance with these requirements is the key to successful work.

Preparation of bulk solution

You need to take a clean, dry container and pour water into it with a temperature of +5 to +25 ° C. Then add the mixture and mix with a construction mixer or drill with the appropriate nozzle for 7 minutes. After that, it is necessary to let the solution brew for about 15 minutes and repeat the procedure. It is better not to cook the composition in large portions, as it begins to set in an average of half an hour.

Attention! It is necessary to strictly follow the proportions indicated by the manufacturer. If you add little water, the mixture will dry out too quickly, possibly even while pouring. Otherwise, the finished coating will be less durable.

The preparation of bulk mixtures is carried out exclusively using a construction mixer or a mixing nozzle

Filling technology

The method of pouring floors in a private house or apartment using leveling compounds practically does not differ from working with a cement-sand mixture, only self-leveling floors dry out faster.

You need to start from the place that is located below everything in level. The material is poured from the container onto the space between the lighthouses and is leveled with the rule, passing them along the lighthouses. After that, you need to roll the area with a needle roller. Treat all strips in this way.

When the material begins to set, it is necessary to get the beacons out of it. The resulting grooves should be filled with the same solution and leveled taking into account the finished surface, which will serve as a level. It is recommended to start further finishing no earlier than a week later.

To ensure that the repair results are not disappointing, you must follow the recommendations:

To equip self-leveling floors on wooden bases, it is necessary to follow the above rules and recommendations given by manufacturers on packages. In addition, it is important to remember that the material dries quite quickly, so it is best to work with a partner.

Do-it-yourself self-leveling flooring on a wooden base raises questions for many. Is it possible? How to do it? What is better to use as a base - plywood, chipboard, OSB or just boards? You will find all the answers you need in our article.

Self-leveling mixtures are compositions of cement or gypsum binder, mineral fillers and modifying polymer additives that improve the basic characteristics of the composition (curing rate, flexural strength, compression, and others).

Manufacturers usually indicate on the label that the mixtures are intended for leveling and repairing mineral-type substrates. These are cement-sand, anhydrite and other types of screeds, concrete slabs, underlying layers of crushed stone, slag, sand, bulk and natural soils (compacted).

And how to find out which compositions can be used on chipboard and OSB-board, wood and plywood. To do this, just look at the instructions. In the description for cement and cement-gypsum self-leveling self-leveling floors, these categories should be indicated among the bases.

For wood and sheet surfaces, the compositions are applied in a layer of 3 to 7 cm.Do not confuse with thin-layer gypsum and gypsum-cement leveling agents, the thickness of which does not exceed 0.2-3 cm.

Since wood and its derivatives (plywood, fiberboard, chipboard, OSB, HDF) have a high coefficient of seasonal variations in linear dimensions, manufacturers strongly recommend the use of separation layers (geotextile, PE film) plus a damper around the perimeter. Simply put - to form a "floating" type floor.

How to choose the right multi-component mixture? See the composition. According to the well-established rule, in complex formulations, the component that is larger is indicated first. For example, a cement-gypsum self-leveling floor contains more than 50% Portland cement and less than 30% gypsum. Although professionals consider purely cement compositions to be the best option. The fact is that their strength is much higher than that of analogs, therefore, a more durable and reliable self-leveling floor on a wooden base can be made.

So, is it possible to do the alignment of the base from a board, chipboard, OSB with your own hands using ready-made compositions? The answer is yes, but with some caveats:

When choosing a mixture, carefully read the instructions, in particular the sections "Composition" and "Types of bases".
Form a "floating" floor using plastic sheeting and damper tape. As a last resort, carefully treat the base with waterproofing compounds (locking primers, impregnators, mastics).

Diy self-leveling technology for self-leveling flooring on a wooden base

To pour the mixture, you will need the following set of tools and materials:

Belt grinder, planetary (surface grinder) and / or angle grinder. It is better to rent professional series devices for 1-2 days. They are more powerful and work in several modes;
Fine-grained sandpaper for finishing sanding (from 180 to 600 units), as well as a belt or nozzles for a grinder (grain size - from 80 units);
Plastic or wooden grater for grinding paper, hand scraper for small jobs;
Construction vacuum cleaner;
Hammer and nail puller;
Sealant or repair putty for filling cracks, gaps;
Waterproofing compounds or polyethylene film with a thickness of 150 microns;
Damper tape;
Roller or ridge for applying waterproofing coating;
Wide spatula or squeegee;
Plastic bucket or container for mixing the solution;
Construction mixer or drill with attachment;
Spot beacons, laser level or water level;
Needle roller for rolling the mixture;
Paint shoes, gloves.

To keep your hands from fatiguing too quickly, choose tools with ergonomic, rubberized grips. They are comfortable to work with and do not slip.

Self-leveling floor on plywood, chipboard or OSB-board should be done in 3 stages.

Stage 1. Wood surface preparation

When working, you must be guided by SP 29.13330.2011. The normative act requires the rolling stock to be poured onto an even (!), Solid and dry base. That is, without stains of oil, paints and varnishes, bitumen and other defects.

First, examine the floor. It should be in good condition: no rot, mold stains, paint residues, varnish, blackness, chips, "playing" boards. The floorboard, OSB and chipboard must be checked for differences between sheets or strips, gaps, creaks.

Removing old paintwork

For painted surfaces, use old paintwork removers. Alternatively, use a hand grater and cycle to gently remove the coating. This will create a fairly rough base on which the waterproofing material will "lie" well and will not slip.

The easiest and most effective preparation method is to grind the entire surface with a planetary or belt unit. Corundum or diamond abrasive will remarkably eliminate all protruding irregularities (slabs, drops), heavy dirt. Manufacturers and technologists strongly recommend not to skip the stage of thorough leveling of the surface for pouring. This is necessary in order to create a single, monolithic cement sheet of the same thickness, and therefore identical strength, without weak areas over the entire area.

For the same purpose, pits, potholes, chips and cracks are filled with an elastic sealant for wood, putty compounds. Professional repairmen devote a lot of time to this, because they know: when rolling the mortar, the needle roller very often simply "tears" the mortar out of the recesses. Because of this, the frozen surface turns out to be uneven. Instead of putties, you can use a simpler option - sawdust mixed with PVA glue.

Plywood flooring on cracked boards.

Walk along the floor and mark where you need to additionally secure the base with screws or nails. Be sure to check every board or floorboard. The minimum spacing between fasteners is 40-50 cm.

If the boards are dry or too damaged, you can additionally sew on top of chipboard or plywood with a thickness of at least 14 mm. And to avoid squeaking between the sheets, pour finely crushed chalk into the gaps.

Do not forget to first remove the skirting boards, as well as protruding metal elements or hardware. "Drown" all fasteners with a hammer 0.5 cm into the floor. After finishing work, go through a construction vacuum cleaner and a damp cloth to remove dust and small sawdust.

Formation of a separating layer from polyethylene.

The next step is the formation of a separating waterproofing layer and its careful fixation. The film is laid over the entire surface with an institution on the walls by 10-15 cm.If strips are used, then they are overlapped by 8-12 cm.

Instead of polyethylene, the use of waterproofing compounds is allowed. And this must be done without fail. The tree and its derivatives do not like moisture, there is a risk of the formation of rotten areas under the ready-made bulk composition. In addition, untreated wood tends to "draw" water from the solution. As a result, the cement binder will not have enough liquid for ripening and full set of strength, and the floor will turn out to be loose, weak, in pits and bumps.

It is known that cement and wood have different thermal expansion coefficients. Therefore, so that in the future the finished base does not crack or damage the walls, be sure to glue the damper tape around the perimeter. It can be replaced with an isolon cut into narrow strips (IPE) with a thickness of 1-2 mm.

Stage 2. Preparation of bulk solution

Pour clean, no impurities, water with a temperature of +5 to +25 ° C into the container. Gently add the dry component, mix with a construction mixer for 5-7 minutes at a speed of up to 500 rpm. The composition should be homogeneous, without lumps and stratification.

Let the solution mature for 5-10 minutes, then stir again. The pot life of the solution is always indicated on the label. This is the time during which the mixture must be used. On average, this is 20-60 minutes.

Stage 3. Pouring a self-leveling self-leveling floor

If necessary, mark the required level of the new cement layer along the walls or place reference beacons on the base.

Pouring a self-leveling self-leveling floor.

Pour the mixture gently onto the surface. Start from the far corner, gradually working towards the exit. Spread the mortar with a spatula or squeegee and roll with a needle roller to deaerate and compact the composition. After 7-14 days, the new flat floor will be ready for laying tiles, porcelain stoneware and other finishing flooring.

Summing up, we note: it does not matter of principle whether plywood or chipboard, HDF or OSB, boards or concrete acts as a base. It is the correct preparation that is important, namely the formation of an even, solid and dry base.

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When repairing a house or apartment, the master may face the problem of a wooden floor. Over time, such coatings become squeaky, lose evenness. Various damages are also possible. To shorten renovation times, it is best to install new flooring without removing the old wood floor.

For leveling the base, a screed on a wooden floor, laid under the tiles, is perfect. It is important to consider this option, since installing the tiles is the most difficult task for a wooden floor. The material is characterized by high density and has a strong effect on the underlying structures. If you understand how to make a screed for a tile, there will be no problems with the rest of the coatings.

How can you make a screed

There are two options for performing work:

standard concrete casting;
using the dry method.

The second option is more suitable for a wooden floor, since it has the following advantages:

small weight;
ease of manufacture;
ease of laying communications;
the ability to correct errors;
lack of wet processes;
there is no need to wait for drying, which requires a cement screed.

But you can also highlight the disadvantages for use in the house:

making a dry screed requires a greater thickness than a concrete one (the height of the room decreases);
due to the increased thickness, the consumption of materials is higher than when creating a traditional base.

Depending on the conditions, requirements and wishes, you can choose between two options when laying the material under the tiles.

Work technology

Screed under tiles on wooden floors should be done in a strictly established manner. When renovating a house, you first need to inspect the floor and floor structures. Identify weak points, make sure there is no serious damage. If traces of decay, mold, the action of fungus and other microorganisms are found, it is better to selectively replace the elements of the wooden floor.

Scheme of preparing a wooden floor before laying tiles, part 1

Scheme of preparing a wooden floor before laying tiles, part 2

Using a screed, you can eliminate irregularities and strengthen the surface before attaching the flooring, but you will not be able to get rid of serious defects. The base for the tiles must be flat and solid, since it will have to withstand serious loads. To prevent problems during operation, it is better to timely replace and remove old boards in the house.

After inspecting the old floor, you can start the main task. It is recommended to fill the classic wet screed in the following order:

If previously there was a cement screed on the floor, it is removed by grinding or milling.
Checking the reliability of the fastening of the floorboards to the joists. If they do not have a secure fixation, a squeak will appear during operation. To prevent this, all the elements of the old floor must be securely attached to each other.
This is followed by cleaning the surface from old dirt. You will need to remove grease, traces of glue, old paint and varnish layer, various impregnations, dirt and dust.
If necessary, sand the surface of the old floor with a special machine. In this way, the top layer is removed, the base under the tiles becomes smoother.
If there are irregularities on the floor with a height difference of more than 1 cm, you need to make preliminary alignment under the tiles. To carry out the work, you can use various leveling mixtures based on a cement binder. The composition covers the surface of the boards, cracks can be repaired with a putty. Do not use water-soluble compounds for putty.
Instead of skirting boards, slats are mounted along the perimeter of the walls, which will cover the distance between the old floor and the wall. Thin slats are installed with subsequent puttying. This rail is removed after completion of the work. It provides a gap that allows air to enter the space under the floor. For wood flooring, this is extremely important, because if ventilation is not taken, the wood will rot and cause trouble during operation.
The leveled surface must be primed in accordance with the technology of this process... For priming, they buy a ready-made mixture. A layer of this material will allow not only to increase adhesion, but also to improve the spreadability of the mixture for pouring the subfloor over the surface during repair work. When processing, the floor must be dry, the work is done in two times.
Having finished with the previous step, you need to lay a reinforcing mesh under the tiles. The diameter of the elements is taken to be 3-4 mm. Cell dimensions 50 by 50 mm. This step can be neglected, but it provides greater reliability of the base and the ability to withstand higher loads.
When preparing the solution, it is necessary to observe the proportions. It is better not to make it yourself, but to buy a ready-made dry mixture, for the preparation of which you only need water. This will avoid mistakes when choosing the proportions of the components and reduce the laboriousness of the screed pouring process.
The mixture must be applied in one go. If the work is carried out in several stages, the layer will not work as a whole, cracks, tears and irregularities will appear. For application, use notched trowels. The thickness of the application is controlled by means of guide-beacons or marks on the surface of the walls.
After completing the laying of the mortar, it is necessary to let the concrete suffice. This process takes several hours under normal conditions. After this time, you can carefully walk on the floor, but for full use it will not be ready earlier than in a couple of weeks (in the summer, for the winter season, the terms increase).
Take out the slats installed along the perimeter of the walls instead of the baseboards. After that, if necessary, you can do the grinding (not earlier than 6 hours after pouring).