Sanding a concrete floor: the secrets to getting the job done well

Grinding the concrete floor eliminates the likelihood of dust generation during the operation of the coating, and also increases its useful life. This type of treatment also affects the aesthetic qualities, since the surface becomes smooth. Various tools are used to carry out this work. To select the necessary equipment and attachments, you need to understand some of the nuances.

Grinding concrete allows you to cope with a common problem - moisture absorption

When and for what purpose concrete floors are sanded

The purpose of sanding is to remove the old, damaged top layer, which was damaged during the operation of the floor. This procedure is also performed in the case when it is necessary to level the screed, before starting finishing work.

To increase the strength of the surface, as well as in order to level it, the concrete floor is sanded

Grinding includes two consecutive events. The initial stage, which is called preliminary grinding, is performed only 3-5 days after the concrete is poured. For finishing, it is necessary to wait until the floor is completely solidified.

Some situations involve filling the grout from scratch. In such cases, milk of lime forms on the surface. Before sanding the screed, it will need to be removed. Old surfaces are much easier to work with. In this situation, the process is reduced to the removal of the surface layer.

Note! This treatment improves the surface quality and removes dirt from it. It doesn't matter when the floor was poured: sanding in any case will increase its technical characteristics and provide visual appeal.

This treatment is also recommended prior to topcoating. Sanding helps create the perfect base. It is also worth mentioning that concrete grinding makes it possible to cope with one common problem - moisture absorption.An uneven surface absorbs moisture more strongly, which can negatively affect its structure, and in some cases lead to destruction.

The quality of grinding depends on the correct timing for it.

However, there are problems that cannot be corrected with such processing. For example, this applies to serious irregularities. Of course, small defects can be eliminated through such processing, but serious differences cannot be removed. Grinding units move along the surface, following its lines.

Concrete floor grinding: advantages of coating

Floor made of pre-sanded concrete is widely used. This is due to its performance characteristics, such as durability, strength, resistance to abrasion and other mechanical stress. The price per m2 of grinding a concrete floor depends on the characteristics of the coating itself and its area. Let us consider other positive characteristics of such smooth coverings.

Particular attention must be paid to the operational life of the concrete floor. It can reach several decades, and in some cases even more. Such coatings can be found in public places around the world. In a similar way, not only concrete, but also marble floors are treated. Sanding results in a glossy, moisture-resistant surface.

A concrete floor can last for several decades

Another advantage of such coatings is their cost. It should be said that a perfectly flat surface can be subsequently sanded and used as the main coating. But also such a floor often serves as a base, which is processed with decorative materials. Such surfaces do not need periodic repairs. If necessary, fixing a local defect is not difficult.

Modern effective methods of concrete polishing

The tools used for grinding work can be used for both concrete and stone floors. Currently, there are two ways that such surface treatment can be carried out:

• wet;
• dry.

The first method is most often used if the floor has a non-standard facing. Examples include mosaic tiles or marble chips. When calculating the cost of work, it is necessary to take into account the price per m2 of grinding. A floor treated in this way is perfectly flat. To carry out such a finish, aggregates and various chemicals (abrasive) are used.

There are special machines for grinding concrete floors

Note! The dry method is more common, as it is used for processing standard concrete (and not only) surfaces.

There are special machines for grinding the floor that allow you to implement this technology. Dry processing takes a long time to complete. This is due to the fact that during the process of dry grinding a lot of dust is formed, therefore, after finishing each area, you have to wait until it settles. And only after that work resumes.

How to grind concrete: detailed classification of equipment

Various devices are used to carry out this type of grinding work. All of them are classified according to such characteristics as design complexity, functionality, cost. In order to select the necessary device for a specific purpose, you need to carefully study the characteristics of individual devices. The following types of equipment are known:

• angular;
• tape;

Wet sanding is hazardous due to wet sludge that permeates the air during operation.

• vibration;
• mosaic.

Devices that belong to the first group are small in size. In terms of design, they have a strong resemblance to the angle grinder (grinder).Grinding surfaces with this type of product requires a lot of time and effort. Some corner units include in their design a mechanism aimed at damping vibration effects that occur during operation. It is also worth mentioning that there are handheld devices that operate on a battery, which is very convenient.

Uses corner models for cutting and processing concrete surfaces. With the help of such manual machines, sanding in hard-to-reach places is simplified. Another plus is that working with them does not require any special skills. However, the disadvantage of angle models is that they are not suitable for large areas.

Grinding a concrete floor with a belt sander differs from the technology used when working with corner models. Draw frames designed for the processing of concrete surfaces include a special belt with abrasive spraying, which moves during operation on roller bearings.

For grinding concrete, you can use a grinder or a helicopter

Important! When using tape devices, a certain pattern can be traced: the higher the speed of the belt, the faster the concrete is ground.

The speed of work when using tape devices is regulated by replacing nozzles that have different grain sizes. These devices are used when it is necessary to perform rough processing of the base (for example, remove the upper damaged layer. The cost of grinding concrete with such an aggregate is slightly higher, since the device removes a thicker layer (10 mm).

The vibration equipment carries out the processing of concrete surfaces with abrasive sheets. Work items are fixed on a special base. Such machines are semi-professional equipment. They are equipped with a planetary mechanism, due to which a high efficiency of grinding of self-leveling floors, as well as any other surfaces, is achieved. The quality of work depends on the diameter of the discs. The lower this indicator, the higher it is. Devices of this type are used to prepare surfaces for finishing.

Mosaic equipment includes working parts, which are represented by disks with abrasive spraying. Such devices are designed for processing natural stone, as well as mosaic surfaces.

The helicopter is used to work with large processing areas

Equipment overview: professional concrete grinders

In order to find the right equipment, you need to consider individual factors. These include the surface area to be processed, as well as the fact how often the device will need to be used. Many home improvement stores offer a wide range of different tools that are used for professional grinding or processing concrete surfaces at home.

Grinding devices differ from each other in their cost. Grinding the floor with a professional unit requires significant costs, since such equipment is more functional and technologically advanced.

Devices of this level include a planetary gear. This is a special drive, due to which special movements of several discs are produced within one geometric axis. This mechanism consists of a main and auxiliary nozzles. All of them move synchronously during operation. Grinding efficiency is achieved by diamond spraying of the disc surface. Professionals use these machines all over the place for grinding floors. The price per square meter of processing with such a unit is usually higher when compared with less technologically advanced devices.

Grinding works are carried out using mosaic grinding machines, which are specialized technological equipment

The design feature of a machine designed for grinding concrete surfaces is that it has a rotating assembly. Abrasive discs are fixed on this element, with the help of which the top layer of concrete is removed. Professional devices are used for large areas and are highly efficient. Concrete floor polishing machines can perform a wide range of tasks and are actively used in the construction industry.

Advantages of professional grinding equipment

Compared to manual devices, which are designed to handle small areas, these machines have many advantages. Let's consider the advantages of such grinding equipment in more detail.

The main advantage of such machines is that they include a regulator in their design. When you switch this device, the rotation speed of the working parts changes. With the help of professional equipment, wet surface treatment is greatly simplified. Concrete grinding machines are capable of supplying liquid in the required amount, which binds dust particles and prevents them from rising into the air.

Dry sanding is also greatly simplified and accelerated, since professional units have a special dust collector. As a result, processing is carried out with minimal contamination.

The use of professional equipment guarantees the quality of the grinding

Note! The modern market offers the manufacturer a wide range of concrete floor grinding machines. Some of them are marketed as equipment for home use.

Work on improving the surface of concrete floors, carried out with the use of special units, is highly accurate. In this case, the maximum error does not exceed 2 mm. Such machines are easy to operate and do not require constant maintenance.

Related article:

Concrete floor repair: features of the restoration process and complete replacement of the screed

Features of performing work in a private house and industrial premises. The cost of repair work. Recommended formulations.

The presence of replaceable nozzles for surface treatment makes it possible to control the roughness of the floor. This allows you to get exactly the result that was conceived at the very beginning of the work. However, for do-it-yourself concrete grinding, it is better to purchase a less complex device.

Special equipment has many advantages, but there are also some disadvantages to using it. First of all, all such machines emit a lot of dust, and they are also quite noisy. Of course, their main disadvantage is their high cost. Before purchasing this or that unit, experts strongly recommend that you familiarize yourself with the list of equipment and study the technical characteristics.

Grinding machines are easy to operate and do not require constant maintenance

Grinder with attachment: equipment for household use

It is impractical to purchase expensive grinding units for household use. If there is a need to correct and process the concrete surface of the house, then the best option is to use a grinder with special attachments.

This device is suitable for fast and efficient sanding of small areas. Such tools have a democratic cost, which is often the determining factor in their choice. Grinding concrete with a grinder has another advantage: due to the compactness of the device, it becomes possible to process hard-to-reach places.

The working tool of the grinder can be a disc. As a rule, it has a small diameter. The efficiency of using the discs is ensured by diamond dusting. Bowl attachments are an alternative to discs.

The quality of concrete surface treatment directly depends on the weight of the tool. For polishing the floor at home, small machines are used, which are equipped with a diamond disc. Such units do not have a planetary mechanism, but they are highly efficient.

With the help of a grinder, it becomes possible to process a concrete floor in hard-to-reach places

Grinding the floor by "helicopter": equipment features

Professional and semi-professional devices that are found on the market today are in high demand. The most popular among them are those models that were released by European and American manufacturers.

Note! The quality of domestic cars is somewhat lower, but they have a more attractive price.

Among all the devices used for grinding floors, it is worth highlighting the models that the craftsmen call "helicopters". The use of such a device allows you to get a perfectly smooth surface. Today, there are two types of such units:

• manual;
• two-rotor.

Models belonging to the first group are characterized by compactness and ease of use. In turn, twin-rotor units are classified as sophisticated equipment for grinding concrete floors. Such trowels are large and have a special operator's chair.

Grinding helicopters are in high demand

Multi-blade trowels perform surface treatment in two stages. First, a low-grade grinding is performed using special attachments that are fixed on the blades. During the second stage, the blades are used directly, moving at high speed.

How to choose grinding equipment: recommendations

There are several criteria to consider when choosing a grinding equipment. One of the most important parameters influencing the quality of processing is the power of the device. It is also required to determine in advance the suitable price of the sander. Sanding a concrete floor is a job that requires care and accuracy. The right equipment is a huge advantage.

The second very important indicator is the mass of the unit. For home use, it is best to choose the lightest models. The dimensions of the working element should also be taken into account, since the quality of grinding depends on this criterion. For machines equipped with abrasive belts, the grit size affects the grinding result.

The right equipment is the key to a well-sanded floor

Another factor that must be taken into account is performance. It depends on the rotational speed of the working mechanism. When choosing, you also need to consider the brand of the grinder. Grinding the floor with units from well-known companies is more acceptable, since such devices are highly efficient.

Professionals recommend paying attention to the additional equipment of the device. For comfortable operation, it is best to choose a device with a minimum noise level. The presence of a vacuum cleaner is also important. High-quality units are equipped with a system that allows you to collect dust emitted during operation. The range of this equipment makes it possible to choose the required model for a specific purpose.

Choosing discs for grinding: characteristics of working elements

When working on a concrete floor, the end result largely depends on which cutting parts are used. When choosing these elements, you must take into account the grade of the material. Grinding wheels for grinder for concrete, they differ in structure and dimensions. The same applies to work items used for other types of equipment.

Important! The concrete grade affects the strength of the floor.If concrete grade M250 or lower was used for pouring the base, then corundum cutting parts are sufficient to perform effective processing. Cement of the M300 brand is distinguished by higher strength characteristics. Corundum elements are not suitable for processing it. In this case, diamond-coated parts are used.

Grinding discs for a concrete grinder differ in structure and dimensions

It should be noted that diamond tools are incompatible with concrete below M250 grade. When processing such material, they quickly wear out. This is due to the fact that the concrete floor, which has little strength, is highly abrasive. For grinding the floor screed, it is best to use a grinder with a diamond bowl or a "helicopter".

It is recommended to consult your dealer before choosing cutting elements. He will help you select the necessary discs or bowls that are most suitable for specific operating conditions.

Do-it-yourself concrete floor grinding: how to make the coating right

The characteristics of a concrete surface can vary greatly depending on which grade of material was used to create it. Also, the properties of this coating are influenced by its operational life. Any concrete floor, regardless of its characteristics, can be sanded. It is more difficult to process a decorative surface, as it requires a lot of labor. It is recommended to hire qualified professionals for this job. The price of grinding a concrete floor will depend on the area of ​​the room and the individual characteristics of the coating.

Grinding is carried out after the concrete surface has gained sufficient strength.

It is important to remember that the surface should not have perceptible height differences (more than 5 mm). When choosing a grade of concrete, you should pay attention to the features of a particular room and its further purpose.

For buildings belonging to the production type, as well as storage facilities, it is customary to use concrete grades from M150 to M300. It is easiest to process such a surface after pouring. In this case, there is no need to organize a decorative concrete floor. The functionality of the coating plays a major role.

In order to create a solid foundation, you will need to purchase cement grades from M300 and above. Experts also advise using a filler in the form of crushed stone during pouring, which allows you to get the most reliable coating.

When filling, it is also worth adhering to some rules. In order to obtain an aesthetically pleasing surface, it is necessary to add marble chips to the solution.

Also, concrete floors are polished if polishing work is planned in the future.

Note! When adding additional ingredients to the solution, it will be necessary to cut off a 10 mm layer of concrete. This will allow the additives to show their color and texture.

Concrete floor grinding technology: preparatory work

Before proceeding with the processing of the concrete surface, appropriate preparation must be carried out. The stage preceding initial sanding includes several important procedures. The first thing to do is to check the floor for cracks, unevenness and other defects. In the event of serious differences in height, this flaw must be removed.

Then you need to tap the concrete surface. This procedure allows you to determine the strength and stability of the coating. Coating subsidence may be detected during tapping. If there is such a problem, it will be necessary to re-fill the base, which will greatly affect the final price. The floor should only be sanded after checking the electrical network in the room. Appliances used for processing concrete surfaces require uninterrupted voltage.

It should also be said that home craftsmen often do not pay attention to the seams that are located between the coating and the baseboards. If such gaps are found, they must be covered with a solution. Building codes contain a clause that prohibits grinding work if there are such gaps.

Preparatory procedures are very important, since the durability of the coating depends on them.

It is possible to independently carry out such work, but not everyone can do it. You can always use the services of specialists, but first it is recommended to determine the cost of sanding the floor. In this case, the price per square meter is multiplied by the total area of ​​the premises.

You should also check the hardness of the coating in advance. This is not difficult to do. All that is needed to perform this check is to sand a small area of ​​the floor and evaluate the final result.

Step by step instructions for sanding

In the upper part of the concrete pavement, there can be reinforcement or a metal net. In this case, it makes no sense to carry out grinding, since the equipment will become unusable. You can remove the reinforcement using a grinder. At the initial stage of grinding, the coating is smoothed. This work can be done in several ways:

• using milling;
• shot blasting method;
• grinder.

Substrate preparation is the most important stage in the construction of a concrete floor.

Most often, home craftsmen use a grinder to level the surface. It should be remembered that this work is carried out with special diamond-coated tips, the grain size of which is from 25 to 30 microns. If you order such work from the masters, you will have to pay a rather significant amount, which is calculated taking into account the scraping. The price of floor polishing on your own is determined solely by the cost of the equipment.

The next stage is the removal of minor defects. For such an operation, epoxy-based materials are widely used. Their use allows you to easily fill in small gaps and holes.

Important! Before proceeding with the surface treatment, it is necessary to wait two weeks after the cement screed has hardened. During this time, the material will have time to acquire sufficient strength.

Only then is it allowed to start sanding the floor with a sander. The price of the work is added to the cost of various impregnations and topcoats (if any).

The price of do-it-yourself floor grinding is determined solely by the cost of the equipment

For direct grinding, a diamond-coated cutting element is most often used. The grain of the disc should be 40 µm. The work is being done gradually. To obtain a perfectly flat surface, you can polish the floor using a material with a grain size of 1500-3000. The final stage is the installation of skirting boards and varnishing (if necessary).

Floor grinding cost per square meter: price overview

There are two factors that influence the final cost of grinding. The first of these is the strength determined by the concrete grade. The second factor is the characteristics of the surface, namely: the size of the drops, the presence of defects, etc. As a rule, the treatment of the floor, which was made of cement grade M300 and higher, costs about 20 rubles more.

The price per m2 of concrete grinding also depends on which processing method is chosen. Wet finishing is more expensive. This is due to the fact that in this case the depth of surface treatment increases. Let's take a closer look at pricing.

The cheapest way is to pre-treat the cement screed. It should be noted that it is performed dry. It will take 5 to 7 days for such a screed to become strong. The price of such a procedure is about 100 rubles. per m².

The cost of grinding concrete is influenced by the strength determined by the concrete grade

Rough processing of cement screed has a higher cost. It will gain strength within 28 days after pouring the floor. The price for 1 m2 of grinding a concrete pavement of this age is approximately 110 rubles. This kind of work is done dry. The tool that allows this procedure is characterized by a fine-grained coating.

Finishing cement screed is cheaper. The price in this case does not exceed 90 rubles. And, finally, finishing is carried out by the wet method, therefore its cost is the highest (120 rubles).

Every person who does not have special knowledge and skills can perform floor grinding. To do this, you need to understand some of the nuances, such as the type of concrete, the characteristics of the units used for processing, etc. Before starting the work, it is recommended to study the step-by-step instructions and strictly follow it.