How to fix cracks and holes in concrete. How to close the gaps in the floor between the boards: cover up wooden ones, seal holes from mice, putty the seams with plywood Leveling monolithic concrete floors

To close the gaps in the floor between the boards, there are many options, you need to study them and choose the most suitable one. A wooden house is the most environmentally friendly and modern building for housing. It is pleasant and cozy to be in it, however, there are a number of problems that the owners of this building face, for example, gaps in the wooden flooring.

Good to know: how to close cracks in a wooden floor

Cracks can occur due to the drying of the tree. The tree dries for 10 years. Deformations of wood in off-season time are possible. In winter, wood swells, and in summer it dries and decreases in size. Visually, this cannot be detected, however, in the microcosm, under a microscope, you can see how the fibers in a tree change over time.

More possible reasons:

Incorrect calculations of builders or incorrect installation of floorboards.
Incorrectly prepared wood for operation - low-quality paints and varnishes.
Bad ventilation.
Insufficient floor fit.
The appearance of mice and termites.

Do-it-yourself grouting of cracks in the floor is a very economical method, but it is not aesthetically pleasing and is used mainly in dilapidated housing or in the country

All cracks, depending on the size and location, are eliminated, you only need to pick up correct solution. There are many methods for fixing cracks in wood floors. Cracks up to 15 cm are filled with sealant. In this case, the sealant can be used in 2 types, it is a silicone or acrylic sealant for wood. Special sealants for wood differ in color, which allows you to eliminate joints and gaps as imperceptibly as possible.

Sealants have a number of advantages: resistance to moisture, favorable consumption in the process of sealing the gap and long operation after the elimination of defects in the floor.

You can fill the gap with wood putty. The choice can fall on acrylic-based, solvent-based, oil-based or polymeric, water-based. You can putty not only cracks and holes, but also irregularities on plywood or wood, as well as cracks. You can seal the gap with foam. However, it is necessary to eliminate cracks very carefully, without spraying foam. Excess foam can be removed only after it hardens.

Cracks are sealed with polyester paste. There can be both one and two-component options. Suitable for sealing gaps and seams up to 5 cm. Sealing gaps with improvised materials, such as slats, tow with paint, glass wool, grout from paste and paper, sawdust and own preparation of putty, is also relevant.

High-quality sealing of cracks in a wooden floor

Regardless of the size of the gap between the boards in the floor or in the parquet, before removing it, it is necessary to do a dry and wet cleaning, remove dust and clean the place of the gap, let it dry.

Termination options:

If the gap in the wooden floor is up to 1 cm in size, then it can be sealed with a tourniquet, grout or filled with sealant.
If from 1 cm to 3 cm, then a special putty is well suited.
If the gaps are very large, then mounting foam, wedges or slats are well suited.

The most common sealing of large gaps in a wooden floor is polyurethane foam.

The field of operations performed, it is better to cover the floor with sheets of plywood, the joints of which are also processed and leveled with putty. Small gaps or joints can be covered with putty made from glue and sawdust.

Sawdust is taken in a fine fraction, poured with boiling water and mixed until a homogeneous mass.

After the solution with sawdust has cooled down, PVA glue is added and applied with a spatula in the localization of the gap cleared of dirt and dust. After the surface of the sealed gap has been leveled to the floor level, it must be left for a couple of days so that the mixture can take and dry. After everything has dried out, the irregularities must be treated with an abrasive, and fire protection should be applied, and only then the selected paints and varnishes.

You need to know: how to close a hole from mice

There are mice in both rural and urban areas. If there are any gaps in the houses, then mice can easily enter the living quarters, they will not only harm human health, as they are carriers of leptosperosis, toxocariasis, streptobacillus and many others, which can be fatal, but also harm room, its decoration, can penetrate food.

A hole from mice, so that they do not gnaw through a new passage in a wooden floor at all, can be patched up with concrete mortar, after putting metal shavings there

The most proven options for sealing holes in the wall from mice are:

glass wool embedment;
Eliminate the defect with cement;
Mounting foam also helps well, mice do not gnaw it, and tightly seal the hole.

The advice of experts comes down to broken glass, which are placed in the holes of mice.

How and how to seal the seams between plywood on the floor

On plywood flooring, you can often find seams and joints that need to be repaired. You need to know that the most important thing in choosing a putty is elasticity, since plywood consists of wood veneer, and the tree is subject to seasonal deformations. Over time, the plywood dries out, and the joints become more visible. It is also worth choosing a putty according to the color of the wood, as well as a special one, that is, for wooden material.

For sealing seams, are used:

acrylic putty;
Elastic sealant;
hot glue;
Sawdust with PVA and gypsum;
Epoxy adhesive.

To seal the seams between the plywood on the floor, it is necessary to choose exactly the putty for wooden floors, since the other simply cannot withstand the load

It is worth considering that chipboard, plywood should be well fixed so that they do not walk and do not vibrate, then the selected putty (putty for wooden floors) will not crack and will hold tightly, closing the gap.

These works are also being done for plywood, on which linoleum will subsequently be laid.

It should also be covered with putty or better silicone sealant, dents in plywood and all joints, cracks. Plywood needs to be coated with an antiseptic. Before laying linoleum, it is necessary to pay attention to the evenness of the plywood and its cleanliness.

Types of putties for the floor from the boards

To date, there is a fairly wide selection of putties on wood. Before choosing a putty, you need to decide on the price, scope, type and brand.

Elastic putty for the floor does not require careful surface preparation, it is easy to apply and cover with other paints and putties

Putties are divided into types:

Polymer putty, which is made on a water basis, therefore, does not emit chemicals into the atmosphere. It dries quickly enough, holds well and does not crack.
Oil putty based on water, chalk and oils. It is one of the most reliable, however, after processing the gap, it takes a lot of time for it to dry completely.
Acrylic putty is environmentally friendly and non-flammable, which is very important for wood.
Solvent-based putty is ideal for parquet flooring, but is not the most environmentally friendly option.
The putty is elastic, which is ideal for “floating” cracks and joints. It keeps its shape perfectly, has good adhesion to the surface.
Pigmented wood putty, that is, various colors (white-birch, teak-mahogany, wenge-dark oak, beech-oak). It must be taken into account that often the color does not match the one declared on the package, you should require a demonstration of the goods or a stand with these putties.
Putty for wooden floors, which is used to smooth out irregularities, various defects and cracks.

The main brands of putty manufacturers are Dulux, Parade, Semin, Varathane, Axton, Neomid, Forwood, Rainbow, Tytan, Master's Choice. We must not forget that putties differ in the main types: finishing, leveling, filling, universal, sealing. Putty is applied with a spatula of the selected size, by pressing it into the depth of the gap. After the putty dries, it is necessary to level the surface using abrasive products for wood.

How to close cracks in a wooden floor (video)

When cracks appear, it does not matter, any gap can be repaired with your own hands, and the wooden floor is easy to install and repair.

Wooden floors differ in high operational and decorative qualities. This is possible if all work on their device is completed without serious errors. Otherwise, you need to be ready for serious repairs and find out in advance how and with what to close a hole in the floor from the boards.

Causes of holes

All the variety of causes that lead to floor damage can be combined into two large groups:

poorly executed base;
floorboard defects.

The first group includes errors associated with lags (defective material, insufficient section), the creation of favorable conditions for the development of mold and fungus, poor-quality performance concrete base or supports.

A hole in the floor may be formed due to the destruction of the floorboards themselves. To reduce the likelihood of such a development of events, it is necessary to avoid the use of low-quality lumber.

Critical defects include:

long through cracks;
dead and dropping knots of considerable area;
damage to wood by a woodworm beetle.

Coating repair

In order to understand how to repair a hole in the floor, it is necessary to assess the extent of the damage. Small areas can be repaired by replacing part of the board between two joists. Sometimes with significant damage, it can be easier to replace the entire floorboard or even several adjacent ones.

A chisel cuts off a piece of wood around the fastener until it is easily accessible. Then the fasteners are removed, depending on what was used nails or self-tapping screws, a nail puller or a screwdriver is used.

The damaged area is selected with a jigsaw, saw blade or manually using chisels. Further, with the help of a crowbar, chisels and a hammer, defective areas of the floor are removed.

The hole in the floor is covered with new, healthy boards. So that they sit on their seat as much as possible, the lower part of the groove is cut off. The board is installed in its place and attached to the lags with self-tapping screws.

Fastener caps are masked with putty.finally appearance the floor is restored after painting the repaired area.

Foundation repair

Floors of the first floor made on the ground are very critical to the quality of the preparation of the base. The concrete screed, on which the floor lags rest, is poured over pre-made layers of compacted crushed stone, hydro- and thermal insulation.

Repair of such floors begins with the removal of a wooden coating. The choice of how and with what to seal holes in the concrete floor is made after assessing the nature and extent of damage to the rough screed.

Most often, screed repair comes down to jointing cracks and filling them with concrete mortar. Large dips are filled with compacted rubble, covered with hydro- and thermal insulation and filled with cement mortar flush with the level of the subfloor.

Repairing concrete floors with your own hands is by no means a simple “lubrication” with cement mortar. Such a "blamba" will not stop the destruction of concrete, will not level the floor and will not block access to fumes through it.

The thing is that concrete, even having gained structural strength, lives its complex physical and chemical life for decades: it changes its structure, gains strength, and then weakens a little until it stabilizes. In fresh concrete, a number of indicators, including shrinkage rate and coefficient of thermal expansion, differ significantly from cured concrete. For the repair of the old floor to be successful, you need to somehow coordinate the properties of the old and new concrete. One of the best ways for minor self-repair is to give fresh cement mortar thixotropic and rheological properties.

Thixotropy and rheology

Thixotropy is the ability of a medium to succumb, to reduce its viscosity with a small but constant impact. A good example of a thixotropic substance is common construction bitumen. If you move your finger along it with pressure, then at first roughness is felt, and then the movement is facilitated and a hollow remains behind the finger. By the way, continental plates move across the face of the Earth due to the fact that the substance of the upper mantle is thixotropic.

Rheology is nothing but superfluidity. This phenomenon is by no means a privilege of ultralow temperature physics. Any housewife who forgot to tightly close the vessel with sunflower oil. However, if liquid helium-II is 100% superfluid, then vegetable oils- units and fractions of percent. But this is enough for the dish to turn out to be all sticky after a while, and kitchen furniture was spoiled.

Under normal conditions, thixotropy and rheology are inextricably linked. Builders, when they say "thixotropy", immediately mean rheology. When repairing a concrete floor, rheology ensures that the smallest irregularities are filled with a repair compound, and thanks to thixotropy, the new concrete mass, figuratively speaking, does not rest against the previous one, but plays along with it.

In construction stores, there is a wide range of thixotropic-rheological mixtures for repairing concrete floors based on epoxy resin and polyurethane. However, to repair an apartment floor, which is in relatively stable conditions and lightly loaded, a cheap thixotropic composition can be prepared independently:

To do this, PVA glue or bustilat is diluted with water three to five times, and a cement-sand mortar is kneaded on the resulting suspension in a ratio of 1: 3. If the amount of work is large enough, you can immediately buy PVA putty. This is the same highly diluted glue, but the minimum package is 5 liters.

PVA-suppension is not suitable for sealing deep deformation cracks; here you will have to buy a branded thixotropic primer for concrete and a repair compound. In this case, you should focus solely on the price: the apartment floor is a light object, and the exclusive quality of the compositions is not required.

Mixer and rule

All repair compounds for concrete must be kneaded: ready-made on water; homemade - on PVA suspension. It is impossible to mix manually: the finished solution should be as “dry” as possible, i.e. water or suspension is added in a minimal amount. A very viscous mixture will have to be “pounded” for too long to the desired uniformity, and irreversible changes will begin in it, worsening the quality of work.

For mixing small volumes of repair building compounds, I use an electric drill or a rotary hammer at low speeds with a special nozzle - a mixer. The principle of its operation is no different from a cocktail mixer.

In tool stores you can find a wide selection of different mixers, sometimes in completely bizarre configurations. But a mixer that is in no way inferior to them is obtained from an even rod 8-10 mm in diameter and half a meter long, the end of which is bent into a ring or simply folded in half.

The kneading lasts 3-5 minutes. When kneading in a bucket, the tool is driven in a circular motion; in the trough - transverse zigzag. A bucket of water should be at hand - after kneading, the mixer must be rinsed immediately, lowered into water and given more speed. When mixing with a perforator, in no case should you turn on the impact mechanism: the whole room and you will immediately find yourself concreted with a thin layer.

In addition to the mixer, to repair the concrete floor, you will need a rule - a meter wide spatula. The plaster trowel will not work: it will not smooth the concrete properly, but it will be erased on it. The rule, on the contrary, is to purchase a factory one, and you should not save on it, especially since it is inexpensive. Concrete is a good abrasive, and if the middle of the rule turns out to be “eaten up”, then the floor will turn out to be humpbacked.

Types of concrete floor repair

There are four different types of concrete floor repair:

Elimination of defects - bulges, potholes, seams from markers and formwork, cracks in the screed.
Seal gaping cracks.
Overhaul of the floor screed for polishing concrete, laying a finishing coating or underfloor heating with insulation and waterproofing.
Dedusting.

Each type of repair is carried out according to a special technology. The most time-consuming and costly repair of the screed under a clean floor. For its overhaul, you will additionally need a metal roller with a width of at least 0.5 m and a weight of at least 10 kg with a carrier handle.

After all types of repairs, except for dust removal, the floor must be kept for at least 20 days before continuing work, spraying it with water every day or wiping it with a richly moistened cloth. It is impossible to fill the floor or wet it more often: the set concrete absorbs a certain amount of water and slowly. "Drinking" will hurt him.

Recommendations on mandatory exposure of 40 or more days, covering concrete with wet burlap, etc. are intended for concreting on outdoors. In relatively stable conditions of a residential or utility room, 20 days of exposure is more than enough.

Room preparation

Preparation for the repair of the concrete floor comes down to the release of the premises and thorough cleaning. Large debris is raked with a shovel, then the floor is thoroughly swept two or three times with a wet broom with spraying. Potholes and cracks after drying the floor after each sweeping are blown with a household vacuum cleaner.

If it is possible to use an industrial vacuum cleaner, the preparation of the floor can be done in an hour: they suck the floor, blow through the potholes with cracks, suck it again - and that's it, the preparation is over.

Concrete floor repair procedure

Repair of the floor in the apartment begins with its inspection and assessment of the condition. Before dismantling the old finishing flooring and cleaning, it is impossible to correctly assess the required degree of repair. The following cases are possible:

The floor is generally level, but dusty, and in places there are potholes, clearly defined small protrusions, or thin, serpentine cracks. Do-it-yourself repairs are possible and inexpensive.
There are gaping cracks no longer than half of the short side of the floor, tending to the perimeter or longitudinal-transverse. Self-repair is possible using branded thixotropic compounds.
The floor is "all humpbacked": small bumps and depressions alternate relatively regularly. Self-repair "on concrete" is possible in a private house or outbuildings.
In a multi-apartment building, there are long gaping cracks on the floor on the floor screed, generally located diagonally or crosswise. Only possible overhaul screeds with a preliminary professional assessment of the condition of the ceiling.

Note to point 3: leveling a carelessly poured screed is possible either with a milling machine or with a liquid leveler after repairing the cracks. Leveling the floor with a hardening compound is the subject of a separate discussion, and the milling machine in apartment building cannot be used: it is very dusty, and the presence of cement dust in the air of residential premises is strictly prohibited sanitary standards. In addition to the “gratitude” of neighbors, one can also fall under serious legislative sanctions, up to and including imprisonment. For example, if a resident is hospitalized with an exacerbation of asthma or a lung disease during or after your work, this is a moderate or severe health hazard. Terms - see the Criminal Code.

Minor patching

Potholes are filed with a grinder with a diamond wheel in a rectangle with a grip of at least 20 mm to the sides. Cutting depth - to the depth of the pothole plus 10-20 mm. Less - if the floor is dense; more - if dusty. The protrusions are knocked down with a puncher or manually to the hollow.
A puncher with a chisel for concrete chooses a rectangular recess in place of the pothole. Small dents can be removed by hand with a 200 g hammer and carbide-tipped chisel. It is impossible to beat with all your might on a dull metalwork chisel: a crack may occur.
The recess is blown with a vacuum cleaner, then the remaining dust is sucked out with it.
Lubricate the recess with one layer of any primer on concrete. Choice - by price; case is not responsible.
After the primer dries, the recess is filled with a thixotropic compound, home-made or purchased, leveled with the rule and left for aging - sealed.

Notes:

Branded repair compounds are kneaded only on sifted quartz sand. It can be purchased from the same store. Proportion - according to the instructions on the package. Thixotropic mixtures in small packages are sometimes sold in a set with sand packaging in the right amount.

Sawing work should be done in a respirator, goggles, earplugs, gloves and tightly buttoned clothes, with wide open open windows, tight closed door and as quickly as possible. Unlike a hypothetical asthmatic neighbor, you will certainly find yourself in the very center of a cloud of cement dust. Headphones in this case protect more from it than from noise.

Repair of small cracks

Small cracks are first sawn through with a grinder along the length to a depth of 20-50 mm and a width of 10-20 mm. As in the previous case, the minimum / maximum depth and width of the cut is determined by the condition of the floor. The cut is also blown and sucked.

How to fix cracks in the floor? If the floor itself is not dusty, and the circle is tight, then a home-made repair mix. If sawing is easy, and the angle grinder sometimes even slips, you definitely need a good branded primer and thixotrope. But if the dust during sawing is so thick that the tool in the hands is hard to see, and / or streams of sand are thrown out from under the circle, you need to close it up in full, like gaping cracks.

The sealing of small cracks is reduced to coating with a primer and filling with a thixotrope, as well as recesses.

Advice: if possible, two to six months before the repair, stick paper strips on the cracks every half a meter. If the paper is not torn for repair - the crack is shrinkage, it will not go further, and you can close it on hastily as described. If at least one piece of paper is torn, the crack is deformational and needs to be repaired in full.

Seal gaping cracks

A gaping crack is considered to be more than 2 mm wide, but this criterion is very relative. More important is the dynamics of the process: will the crack go further or not. You can independently evaluate the dynamics, without having building experience, using the “paper” method described above or by turning on a laser level with a sensor or reflector on the opposite wall for several days. If, for example, the light spot has gone by an average of 0.01 mm per day, then for the year it will be 3.65 mm - the situation is emergency, and you need to think about the overhaul of the entire building.

If the condition of the building as a whole does not cause concern, then the repair of gaping cracks is carried out as follows (see figure):

The crack is sawn 50-60 mm deep and 20-30 mm wide.
The edges of the cut are knocked down to form a triangular hollow.
The cut is carefully blown and sucked.
The hollow is treated with a primer.
After the primer dries, markers are inserted into the cut in turn. Holding the next marker vertically with your hand, the hollow is covered with a thixotropic compound, leveling it with a rule. Homemade thixotrope in this case can not be used!
When the thixotrope sets, the markers are removed, and the seam is cut through the holes from them to the previous width.
A damper cord of the Viloterm type or similar is placed in the seam. Clotheslines, synthetic ropes, etc. are not suitable.
The seam is finally sealed with silicone or polyurethane sealant; in no case with mounting foam, epoxy or other fully hardening compounds.

Note: markers - thin smooth metal bars. Excellent markers are obtained from bicycle spokes. To make it easier to remove later, markers can be lubricated with grease before installation.

Overhaul of the screed

Overhaul of the screed means, in fact, its replacement. This is an extreme measure, costly and time-consuming. They go to it if it is supposed to be laid or finished, and the moisture test gave an unfavorable result.

More about formation various kinds floor screeds from scratch can be read at the links below:

Screed thickness calculation

If repairs are made in a room adjacent to others, then the floors should be on the same level. And in any case, the finished floor should not be higher than the threshold of the door. Therefore, the calculation of the thickness of the screed is carried out from the bottom up with a margin upwards. In this case, the level of the base floor will be lower, but this can be compensated by increasing the thickness of the plywood bedding or the height of the logs. The thickness of the solution layer above the reinforcing mesh must be taken at least 8 mm.

Calculation example: from bare ceiling to door threshold 80 mm. Initial data:

Waterproofing - 1 mm.
Expanded clay bedding in one layer - 25 mm.
Reinforcing mesh - 6 mm.
The concrete layer above the grid is 8 mm.
Layer of mastic - 1 mm.
Plywood - 8 mm.
Adhesive layer - 1 mm.
Laminate - 16 mm.

The total is 66 mm. You can improve thermal insulation by pouring one and a half layers of expanded clay or taking thicker plywood. However, laying the floor on the logs will not work, except perhaps to abandon expanded clay thermal insulation, but such a floor will be colder and more sensitive to dampness.

Screed markers

The screed is leveled with pin or plaster lath markers. Both of them are immured with a small amount of cement-sand mortar (see the figure below):

Pins - in the corners and along the walls in half a meter or less.
Plaster markers - parallel to the short wall. The first is 25-30 cm from her; further - half the width of the rule from each other.

Pins can be made from improvised materials, and plaster markers will have to be bought, and expanded clay will need to be rolled very carefully. But even an experienced craftsman is unlikely to be able to withstand the horizontal surface better than 3 mm / m using the pins, since as a rule you will have to work without additional support.

The height marks on the pins are made with a tightly stretched cord and a bubble level, starting from the corner closest to the door diagonally. Then, the second diagonal is beaten off along the primary cord, the cords are pulled around the perimeter and marks are made on the wall markers. To speed up the beating of heights, you can use a laser level, but this will not improve the accuracy and smoothness of the floor, see above.

Screed overhaul procedure

Lay waterproofing ( plastic film) with an overlap of 0.5 m and an overlap on the walls of 10-15 cm. The joints along the entire length are glued with adhesive tape.
Expanded clay is poured and leveled with a rolling roller. Under the draft floor, it is permissible to use a manual rammer, wooden or metal.
A reinforcing mesh is laid with an overlap of 1-2 cells and with an indent from the walls of 30-40 mm.
Priming markers.
If pin markers are used, after the curing is set, the heights are marked.
Knead in portions of 10-20 liters of a viscous cement-sand mortar (1: 3); thixotropic additives are optional. At the end of the kneading, the next portion is dumped between the markers next to the previous one.
Each portion of the solution is leveled with a rule, starting from the far wall: along a cord or with the support of the rule on two adjacent markers. The rule is held obliquely so that excess solution falls into an empty cell.
The kneading of the next portion is started after leveling the previous one.
After the solution hardens, the markers are removed and the grooves are sealed with a solution.
Excess waterproofing is not touched; they are cut off after installing the plinth.

Note: under the draft floor, instead of plaster markers, you can use wooden logs-lighthouses, even and of the same height.

Video: an example of pouring a screed

Dedusting

Quite serviceable, but dusty due to surface wear, the concrete floor can be quickly repaired with special compounds:

Draft floor and floors in outbuildings - domestic Neomer-LP, Elakor-PU or imported Ashford formula, etc. They give a layer of 150 microns.
Finished concrete floor in living quarters, garage, workshop - GruntElast-PU, Elakor-ED, Retroplate. Layer - 250 microns.

In terms of quality and cost, these compositions are approximately equivalent.

Outcome

Do-it-yourself concrete floor repairs can be as simple, quick, and cheap as they can be complex, difficult, and expensive. The need for repair of one degree or another, in addition to the presence of gaping cracks, can be determined independently. In any case, it is definitely beneficial for self-fulfillment only to dedust the worn floor from the surface.

Despite the strength and durability of concrete floors, even they need regular maintenance. Violations of the technology of laying such a floor, the features of its operation, improper maintenance can lead to problems in the form of cracks, chips, potholes, swelling and other surface defects. Repair of concrete floors allows you to return the coating to its original appearance and high performance. In some cases, repairs can be done by hand, and to eliminate complex defects, you will need to involve specialists.

Causes of concrete floor defects

Even if the concrete floor laying technology was strictly observed, cracks and other defects may appear on the surface. Among the main reasons leading to problems with concrete floors, you can list the following:

The destructive effect of the soil base can lead to swelling and unevenness of the surface of the concrete floor. At the same time, the front layer of the floor remains absolutely smooth and without cracks. Its unevenness can be caused by swelling of the soil in the cold season in a warehouse without heating, shrinkage of the structure, exposure ground water or insufficient tamping of the base during the flooring process.
Cracks in the floor surface can be caused by improper care of the concrete surface immediately after it is laid. Internal factors cause shrinkage of the floor and delamination of the top layer. As a result, the floor begins to crumble, potholes and chips form on it.
The negative influence of external factors leads to "dusting" of the surface. Due to significant regular loads on the floor from heavy objects and vehicles, potholes can occur.

Types of repair of concrete floors

The concrete floor repair technology involves four types of work:

Repair of minor surface defects formed after removal of markers, removal of formwork, due to traffic. These include small cracks, bulges, potholes on top layer gender.
Repair of deep surface damage. In the course of the work, deep deformation and shrinkage holes and cracks will have to be repaired, and chips will be eliminated.
Overhaul concrete surface is done if it is planned to polish the front layer, lay a new flooring or perform waterproofing and floor insulation in a warehouse or in another room.
Dedusting. If the floor began to crumble and dust, it is necessary to carry out repair work to dedust the floor.

Important: After completing repair work, except for dust removal, the floor cannot be operated for three weeks. During this time, the concrete will fully set and gain the desired strength. At the same time, during the first week, the surface of the repaired floor should be regularly moistened with water to prevent shrinkage and cracking.

Preparatory work

Repair of concrete floors can only be started after a thorough preparation of the warehouse or other premises. To do this, do the following:

Remove all furniture and work equipment from the premises.
Large debris is collected with a shovel, and the floor surface is sprinkled with water and swept.
All holes and cracks are well blown with a vacuum cleaner.
After they are blown, the floor is swept again.

Tip: It is much faster and more efficient to clean the floor with an industrial vacuum cleaner. Such equipment can be well blown and cleaned of all floor defects.

Damage assessment and choice of repair tactics

Before starting repairs, the floor should be carefully examined in order to assess the degree of damage to it and choose the appropriate tactic for further action. Floor in warehouse or other industrial premises may look like this:

In general, the floor surface is even, but in some places there are small holes and a fine network of cracks. Repairing this floor is easy to do with your own hands.
If large holes and deep longitudinal or transverse cracks are visible on the surface, then repairs are best done using thixotropic compounds.
If the floor crumbles heavily, cavities and bulges are visible on its surface, then just patching up the holes will not be enough. It will take a thorough repair of the floor screed using special mixtures.
The floor is crumbling, it is all covered with deep cracks, potholes, in some places the top layer is peeling off. In this case, a major overhaul will be required.

Repair of small holes

Do-it-yourself concrete floor repair can be done if there are small holes on a relatively flat surface. The sequence of repair work is as follows:

To close up small holes, you need to use a tool with a diamond wheel to expand the pothole, capturing 2 cm of the floor on each side. In depth, the hole also needs to be cut out by 1-2 cm. If the floor is hard enough, then the amount of capture from all sides can be slightly reduced. On dusty floors, on the contrary, it is worth making a deeper and wider cut.
Further, with the help of a perforator or a chisel, concrete is knocked out of the expanded hole. This must be done very carefully so that a crack does not go.
The vacuum cleaner blows the pothole well and cleans the floor around it from debris.
Next, a primer on concrete lubricates all surfaces in the hole. It is enough to apply one layer of primer.
When the primer dries, a thixotropic mixture is placed in the hole. You can buy it or cook it on the spot.

Repair of shallow cracks

The technology for repairing small cracks involves several stages:

Small cracks are expanded with a grinder. To do this, it is enough to capture 1-2 cm of the floor in width, and 2-5 cm in depth. Depending on the strength of the floor, the cut can be reduced or increased.
Seal cracks on non-dusty floors can be done using a home-made repair compound. Dusty, fragile floors with cracks are repaired with branded primers and a thixotropic mixture. It is applied after the primer has dried on the walls of the expanded crack.

Tip: in order to understand the nature of the crack, two months before the start of the repair, it is necessary to seal it with paper strips in increments of 50 cm. If during this time the strips do not tear, it means that the crack has formed due to concrete shrinkage and will not expand anymore. It can be repaired with ordinary mortar. If at least one strip of paper breaks, the crack is considered to be a deformation crack, it must be repaired as described below.

Repair of deep cracks

A crack is considered deep if its width is more than 2 mm, but this parameter is relative. The nature of the crack is important. Deformation defects can increase over time and can only be thoroughly repaired. Repair of deep cracks should be done in this order:

With a grinder, the crack opens in width and depth by 2-5 cm, depending on the condition of the concrete floor.
The edges of the recess must be knocked down so that the cut expands upward.
The crack is cleaned of debris and dust.
The excavation is treated with a primer.
Next, the crack must be covered with a thixotropic mixture by placing markers in the recess. When the composition grabs, the markers are removed.
The crack cuts through the holes from the markers again.
A damper cord is placed in the resulting seam.
From above, the seam is closed with a polyurethane or silicone sealant.

Important: to seal the seam, it is forbidden to use hardening mixtures, such as polyurethane foam or epoxy resin.

Floor overhaul

This type of repair is complete replacement the top layer of the screed. It goes through several stages:

After the complete dismantling of the old screed, a viscous cement-sand mixture is prepared in a ratio of 1: 3 and laid on the floor according to pre-set markers.
The laid portion of the solution is leveled by the rule. The next portion can be laid after the previous one is completely leveled.
When the concrete composition hardens, the markers can be removed and the holes sealed with mortar.

Floor dedusting

For dedusting rough concrete floors, you can use mixtures of domestic production Ashford, Elakor-PU or Neomer. They are suitable for floors in outbuildings and utility rooms of industrial enterprises.