Concrete floor repair

2024 Author: Arianna Cook | [email protected]. Last modified: 2023-12-17 14:23

For what reasons can the concrete floor collapse, the rules for eliminating various damages - potholes, cracks, irregularities, surface overhaul technology. Repairing a concrete floor is a rather demanding process. The reliability of the coating and its durability depend on the correctness of its implementation. Subject to a number of rules, it can be done independently, without involving professionals in the work.

Reasons for the destruction of the concrete floor

After a certain period of time after the installation of the concrete floor, even if the basic operating requirements are met, it will begin to require repair. Before proceeding with these works, you need to make a preliminary diagnosis. This is necessary to select the appropriate surface repair technology and the required mixture.

The main reasons for the destruction of a concrete floor:

• Subsidence of the soil under it due to the shrinkage of the structure, poor heating in the cold season, poor quality of preparatory work, the effects of groundwater, external effects of moisture, and other factors. Most often, for such reasons, internal destruction of the structure occurs, and the external side remains unchanged.
• Deformation and destruction as a result of violation of installation technology, external influences immediately after pouring.

In addition to destructive factors, the nature of the damage is of great importance:

1. Local … This is the formation of cracks or pits in one place. In this case, it is enough to take measures to eliminate the influencing factors and carry out spot repairs.
2. General … Requires complete removal of the old coating and the installation of a new one.

Based on the causes and nature of the damage, the concrete floor screed should be repaired. It is necessary to eliminate such damage: peeling of the upper layers, significant shrinkage in the first hours after installation, the appearance of cracks, pits, chips, dusting of the upper layer, significant wear of the coating.

Concrete floor repair technology

After you have assessed the nature of the destruction and the scope of future work, you need to purchase or rent a tool and buy materials. Next, we determine the procedure for carrying out repairs. You can do it yourself if you strictly follow the technology.

Selection of materials and tools for concrete floor repair

Modern construction stores offer a huge selection of ready-made mixes for concrete floors. These can be simple mixtures or with the addition of various additives that improve the properties of concrete. Most often on sale you can find compositions with high rheological and thixotropic properties. They are made on the basis of epoxy resin and polyurethane. These ingredients significantly improve the quality of finished floors, extend their lifespan and prevent cracks, unevenness and dusting.

If the amount of work is small, and the house is stable and the floor has a low load, then you can make a mixture with thixotropic properties yourself. To do this, mix PVA glue or bustilate with water in a ratio of 1: 5 and mix a cement-sand mixture 1: 3 on this suspension. For a significant amount of work, you will need a PVA putty and a thixotropic primer. For small cracks and chips, it is better to choose a PVA suspension. The concrete solution should have a homogeneous structure and be "dry" at first glance. You will not be able to achieve this state by mixing it manually. Moreover, it is necessary to introduce a suspension or ordinary water into the preparation composition in small quantities, constantly controlling the consistency of the mixture. That is why at home it is best to use a special mixer or mixer attachment for a drill (perforator). The mixers offered in stores today are distinguished by a rich configuration and a large run-up in pricing. If you wish, you can make the device yourself at home. To do this, you need a one and a half meter rod with a diameter of up to 10 mm. Using pliers, it must be bent in one direction in a semicircle or a ring.

If the volume of the floor to be repaired is significant, it is better to give preference to a small concrete mixer. In addition to the equipment listed, you will need mixing containers (most often plastic or galvanized buckets are chosen for this purpose), wide spatulas, levels and rags.

Preparation of the floor surface for repair

After you have purchased all the necessary materials and tools, you can start preparing the floors. In order for the screed to lay down in the right way and serve you for a long time, you should carefully approach this process.

This procedure consists of the following steps:

• First, you need to completely free the room from various pieces of furniture, carpets and other elements.
• The next step is to thoroughly dry the floor in a well-ventilated area.
• Large pieces of fallen concrete must be collected with a broom (broom), and then, after sprinkling the floor with water, thoroughly sweep the entire room with a broom several times.
• Any cracks, pits or chips in the floor must be thoroughly blown out using an industrial hair dryer or a household vacuum cleaner.
• Rust, mildew or old filler marks are removed with a metal bristle brush.
• If there are paint or grease stains on the floor, you must use a special chemical solution, which can be purchased at the store.
• If reinforcement is laid in the floor, then it must be thoroughly cleaned and coated with an anti-corrosion agent.

After carrying out these activities, you can proceed to sealing cracks and potholes.

Features of eliminating potholes in a concrete floor

Over time, under constant mechanical stress, potholes or small pits can be observed in the same place. They must be removed immediately after they are discovered, as they lead to further destruction of the concrete pavement and the need to redo the screed throughout the room.

The process of repairing potholes in a concrete floor boils down to the following steps:

1. Using a diamond blade, cut a pothole around the perimeter up to 2 cm deep.
2. Using a hammer drill, break the old concrete into pieces.
3. Using a broom and a vacuum cleaner, we thoroughly clean the surface from the formed debris. It is also recommended to walk on the floor with an industrial hairdryer or sandblasting.
4. We cover the prepared potholes with epoxy primer.
5. Fill the holes with the ready-made solution. With a pothole depth of more than 5 cm, it is best to lay the mixture in layers of 1-2 cm. The next one should be poured only after the previous one has frozen.
6. Using the rule (rail), level the surface.
7. After the composition has hardened, we grind the repaired area. In this case, be sure to measure the floor level with a building angle. This will allow you to get a flat surface without bumps and depressions.

Subtleties of filling cracks in concrete floors

In the same way as the elimination of potholes, the removal of cracks in the concrete screed is also local in nature. It is necessary to eliminate them immediately after they are discovered. This is due to the fact that the crack reduces the strength of the floor and contributes to its early destruction. In addition, debris, dust, moisture and so on begin to get into it. She begins to dust and stain the room.

The smaller the crack, the easier it is to repair. Therefore, do not postpone the work to eliminate it. The sequence for repairing cracks in a concrete floor is as follows:

• If the depth of the crack is not more than 2 cm, then we increase it by 1 cm. If the depth is greater, then we increase it to 5 cm. For this, it is best to use a diamond disc. It will turn out smoothly and neatly.
• If the crack is deep, then we make additional ditches on both sides of it and only then proceed to deepening.
• We carefully remove the crushed concrete, and the surface is cleaned of dust using a vacuum cleaner, an industrial hair dryer or a sandblasting machine.
• Now we proceed to treat the edges of the groove with a primer based on polyurethane or epoxy resin. Before applying, it must be diluted with a solvent or white spirit in a ratio of 1:10.
• Fill with ready-made solution. It is best to choose a polyurethane or epoxy mixture previously diluted with quartz sand.
• We fill deep cracks in layers. Only after the first layer has frozen should you start laying a new one.
• When the concrete solution has dried well, we grind the resulting surface, constantly controlling the height with a level. Thus, we get a smooth, even floor.

If the crack being repaired is wide, then it should be reinforced with ordinary reinforcement. For this, shallow grooves are cut at the base at regular intervals. The fittings are laid in them. Now you can pour the finished solution in layers.

The process of leveling unevenness in the concrete floor

There are times when the presence of irregularities in the surface requires a local repair of the concrete screed. They can appear both in old houses under the influence of constant gravity in one place, and in new ones.

To remove this defect, a grinder is most often used. If this is not the case, a grinding attachment for a drill will do. Sequential repair comes down to the following steps:

1. We thoroughly clean the area to be treated from debris and dust.
2. Impregnate with a solvent-based primer based on polyurethane or epoxy resin.
3. Fill the prepared area with a solution and level it.
4. When the concrete mixture has hardened, we grind the surface to the general level of the floor.

Overhaul of the concrete floor

There are often cases when concrete screed problems are not local, but general. In such cases, the entire surface becomes unusable and requires a complete replacement.

It is necessary to overhaul the concrete floor in the presence of 30% damage from the entire surface. The old screed is also removed when laying a warm floor or replacing old linoleum (laminate, parquet) with a new one.

It should be remembered that in the room being repaired, the floor level should be the same as in the adjacent one. The screed level cannot be higher than the threshold. Consider these requirements when troubleshooting problems.

The sequence of overhaul is reduced to the following:

• Before starting the repair, we calculate the thickness of the new floor. In this case, you should go from bottom to top. This is necessary in order to correct the deficiency by laying litter if the level is less than required.
• We thoroughly clean the surface to be repaired from debris. To do this, you should use an industrial vacuum cleaner or a special compound.
• We treat the prepared surface with a primer. This will provide the necessary grip. If there is high humidity in the room, then a primer should be chosen with moisture-repellent properties.
• Before processing, we carefully grind the surface cleaned from the old screed. In this case, you will need a sander that can be rented.
• Let's start applying the primer.
• After the impregnation has dried, we begin to pour the concrete screed. This must be done in stages. To begin with, we fill in a self-leveling mixture for repairing a concrete floor. The resulting layer should be 5-10 cm.
• On the finished surface, we must go through a needle roller. This will remove air bubbles from the concrete.
• After the first layer has set, apply the second if necessary.
• When the concrete screed hardens, we carefully check the surface for defects before the bequest grinding. If there are any, they must be removed immediately. Thus, you will extend the life of the renovated floor.

It is possible to install objects or act on the surface of the concrete screed in another mechanical way no earlier than in a month. By this time, the floor will be completely dry. How to fix cracks in concrete floors - watch the video:

The process of repairing a concrete floor with your own hands is not a complicated procedure. However, it requires adherence to the rules and accuracy. If you are not confident in your abilities, then it is better to entrust the job to professionals, so as not to carry out repair work too often.