The garage is not just a place for parking a car, but a full-fledged workshop and warehouse, where the flooring experiences enormous mechanical loads. If the base is weak or uneven, this will lead to rapid destruction of the coating, problems with the installation of racks and discomfort during operation. That's why. screed It is the foundation of the entire room, requiring strict adherence to technology when laying.
Many property owners mistakenly believe that it is enough to simply pour cement mortar into an old stove, ignoring the nuances of preparation and reinforcement. This approach often leads to cracks, material detachment and dust formation in the first year of operation. In this article, we will discuss in detail the professional approach to the creation of wear-resistant floor that will withstand the weight of the SUV and the fall of heavy tools.
The process of creating a solid base requires attention to detail at every step, from dismantling the old coating to final drying. We will look at the choice of materials, reinforcement methods and secrets that professional builders use to achieve the perfect result. Properly executed work will allow you to forget about floor repair for decades.
Analysis of the condition of the old concrete base
The first and critically important stage is a thorough revision of the existing concrete slab. Visual inspection is not enough here: you need to tap the surface with a hammer throughout the area to reveal hidden voids and areas of detachment. A deaf sound during impact signals that a cavity has formed under the upper layer, and such a site requires mandatory removal to a solid base.
If there are deep cracks on the surface, they can not simply be smeared from above. Required. defect-fixing Bulgarian with a diamond disc or punch to remove the destroyed material and give the crack a V-shaped shape for high-quality filling with repair composition. Ignoring this rule will cause the new screed to burst in the same places due to the shifts of the old base.
⚠️ Attention: If the elevation difference on the garage area exceeds 2-3 cm, simple alignment may not be enough. In such cases, preliminary cock-up ceramsite or the use of a thicker layer of solution with mandatory reinforcement.
Particular attention should be paid to waterproofing, especially if the garage is located at ground level or below. The presence of dampness protruding through microcracks indicates a violation of the waterproofing circuit of the foundation. In such a situation, the device of a new screed without prior cutting off waterproofing This will cause the insulation to get wet and the concrete to break down in the winter.
How do you check the moisture of the concrete?
Take a piece of plastic film size of 1×1 meter and glue it with tape around the perimeter to the floor. Leave it for 24 hours. If condensate or concrete has darkened under the film, the humidity is increased, increased waterproofing is required.
Necessary tools and material calculation
To perform the work, a specific set of equipment will be required, without which it is impossible to achieve professional quality. The main tool for mixing large volumes of solution is concrete mixerSince manually prepare a homogeneous mixture in the right amount is extremely difficult and long. Also (necessary) laser level or hydraulic level for accurate marking of the horizon.
When choosing materials for the bulk of screeds, cement-sand mixture or ready-made dry compositions are most often used. For the garage, the best grade is considered to be not lower than the M200-M250, which provides high resistance to abrasion. If you are planning to use ready-mixMake sure that they are designed specifically for industrial or garage spaces, not for living rooms.
Below is a table of approximate material consumption for creating a screed thickness of 5 cm on an area of 20 square meters (standard single-bed garage):
| Materials | Unit of measurement | Consumption per 1 m2 (thickness 1 cm) | Total 20 m2 (5 cm) |
|---|---|---|---|
| Cement M500 | kilogram | ~4.5 - 5.0 | ~450 - 500 kg |
| quartz sand | kilogram | ~13.0 - 14.0 | ~1300 - 1400 kg |
| Water. | litres | ~2.0 | ~200 litres |
| Plasticizer | millimeter | manually | brand-dependent |
Don’t forget to take care of personal protective equipment in advance. Working with cement dust and alkaline solutions requires a respirator, tight gloves and protective glasses. Also for the alignment of large areas is highly desirable presence vibrator Or at least a long rule (2.5-3 meters) to effectively stretch the mixture.
Surface preparation technology and waterproofing
After the old base is cleared of debris, oil and dust, the priming stage begins. Use of the deep-penetration (Primer) is a prerequisite, as it binds residual dust and improves the adhesion (adhesion) of the new layer with the old concrete. Apply the soil in two layers, allowing the first to dry completely before applying the second.
Along all the walls along the perimeter of the garage, it is necessary to fix the damper tape. This element of foamed polyethylene compensates for the temperature expansion of the screed and prevents the formation of cracks during shrinkage. The height of the tape should be slightly more than the planned floor thickness, and after drying, the excess is easily cut with a knife.
☑️ Preparation of the base for pouring
If the garage is in the risk zone of flooding or the level of groundwater is high, it is mandatory to lay a waterproofing membrane. Dense polyethylene film (at least 200 microns) or specialized roll materials are laid with a overlap of 15-20 cm, and the joints are necessarily glued with construction tape. The film should go on the walls above the level of the future screed, creating the effect of "trench".
For garages where it is supposed to store the car, often used a combined method of protection. On the concrete slab is first applied asphalt waterproofing on the basis of bitumen at the corners and joints, and then rolled material is rolled. This double protection minimizes the risk of moisture and aggressive technical fluids entering the floor structure.
Reinforcing: grid or fibre?
The question of choosing the type of reinforcement is before everyone who decided to make the floor in the garage with their own hands. The traditional solution is the use of a metal welded mesh with a cell of 100x100 mm and a diameter of a bar of 3-4 mm. This material significantly increases the tensile strength, but has one significant nuance: the grid must be raised above the base by 2-3 cm so that it works in the body of concrete, and not lying on the ground.
The alternative to metal is becoming fibre (fibre) - polypropylene or steel microfibers that are added directly to the solution when kneaded. The fibra creates chaotic three-dimensional reinforcement throughout the volume, which effectively prevents the appearance of microcracks during shrinkage. For a garage, the best option is often considered a combination: a fiber for bulk strength and a metal mesh in the lower third for load-bearing capacity.
- 🔹 Metal mesh is ideal for floors with high dynamic load (constant arrival of heavy vehicles).
- 🔹 Fibre fiber significantly accelerates the laying process, since the time-consuming stage of mating and raising the mesh disappears.
- 🔹 The combined method (fibre + grid) gives the maximum result, but increases the cost per square meter.
⚠️ Attention: When using a metal mesh, never lay it directly on waterproofing or concrete. Be sure to use special plastic fixers (“chairs”) or stone/brick linings to get the fittings inside the concrete layer.
If you choose a grid, it is important to dock the canvases correctly. The sheets should lie overhead for at least one cell, and in places of joints it is desirable to bind them with wire. This will ensure the monolithic design and uniform distribution of the load throughout the garage area.
Installation of beacons and preparation of solution
The quality of the future surface depends on the accuracy of the installation of lighthouses. As guides, it is most convenient to use special perforated plaster profiles or square pipes. Lighthouses are displayed in parallel rows at a distance slightly shorter than the length of your rule, fixed on "slaps" of thick cement mortar or alabaster.
The process of setting the horizon requires a laser level. The beam is projected onto the walls, and the height of each lighthouse is checked using roulette.
Making a solution is the art of balance. Too liquid mixture (“milk”) when drying will give a strong shrinkage and cracks, and excessively dry will not allow to compact the material qualitatively. The consistency should resemble thick sour cream: the solution slowly melts, but holds the shape. To improve plasticity and reduce the risk of cracking, be sure to use plasticizer.
Use a semi-dry screed for the garage. A mixture that can be molded into a lump, but it does not release water when compressed, dries faster and produces less shrinkage than a classic liquid solution.
It is better to mix large volumes in a concrete mixer, observing the order: first water with a plasticizer, then cement, and only at the end of the sand. This arrangement allows for uniformity. If you are using ready-made dry mixtures, follow the instructions on the package regarding the amount of water, but always monitor the consistency visually, as the moisture content of the filler sand can vary.
Screed fill and finishing
The filling should start from the far corner of the garage, gradually moving to the exit. The solution falls between the lighthouses and is distributed by a shovel, after which the rule is taken. He moved it with zigzag movements and leaned on May.