2023 Author: Philip Bishop | [email protected]. Last modified: 2023-05-24 22:24
- Types of screeds for leveling
- Screed requirements
- Materials used
- Recommendations for screed construction
- Making a screed from sand and cement
- Self-leveling mixtures
- Dry leveling method
Laminate is very popular among floor coverings. This is due to the large number of positive qualities and reviews of performers. It is worth paying attention to the fact that the laminate requires very careful attention to the process of leveling the base of the floor in the apartment where the repair is being carried out. It is for this reason that floor screed options should be considered that can be used prior to laying the floor covering.
Types of screeds for leveling
The screed device is performed in order to ensure that the base under the laminate is perfectly flat. This will contribute to the durability of the entire structure, as well as the absence of negative manifestations during the operational period.
The screed is divided into two main types, each of which differs from each other in the materials and tools used, as well as in the work process:
Wet screed. The base of the floor in the room is filled with a prepared cement-sand mortar, after which it is evenly distributed over the entire area.
This process is characterized by increased complexity, where it is impossible to do without accuracy and adherence to all the subtleties. Additionally, the "cake" can be strengthened with a reinforcing mesh or adding special additives (fiber) to the cement-sand composition. In this case, the base will not only be durable, but also strong, capable of withstanding external influences with ease. Another option for wet filling is the use of self-leveling mixtures, which are gaining more and more interest. The screed installation process is noticeably reduced, but they can only be used with unevenness no more than 20 mm. In all other cases, you cannot do without the classic mortar made of sand and cement.
- Dry floor screed for laminate. Here, the process does not take much time, but it also requires effort. All existing protrusions, depressions, potholes and other irregularities in the base of the floor in the room are covered with a layer of expanded clay of a certain thickness. After that, all that remains is to lay the plywood sheet or chipboard on top. But the reliability and duration of the use of such a "pie" is not enough. This method of leveling the subfloor is applicable in most cases with a plank surface. The rough base must be carefully sanded, after which a sheet of plywood is laid over the entire area. Therefore, you can do without expanded clay.
The choice of a specific option for leveling the floor under the laminate will depend on the contractor, as well as his capabilities. In any case, you should adhere to the technology and sequence of performing all actions.
The base of the floor under the laminate must be properly leveled. At the same time, before the flooring is laid, the floor screed for the laminate must be rigid. These are the requirements made by the manufacturers of laminate panels. For each square meter of the area of the room, only a slight difference in height is allowed, which should not exceed 2 mm. You don't even need to talk about the fact that the presence of various damages in the form of cracks, potholes, etc. is not allowed on the surface.
To determine the clarity of the base, you can use a rule-ruler, the length of which is about 2 meters. She gradually settles on the floor, trying to find level differences. Any faults that are found prior to laying the flooring must be removed immediately.
If the errors are insignificant, then you can leave them. All of them will be hidden later when laying the substrate under the laminate. The main thing is to choose its quality option. Several layers of substrate still cannot get rid of potholes and significant drops.
In the absence of communications under the future floor covering, the screed is made in a height of 35-45 mm. But here you need to immediately know that the drying period for such a "cake" will be about a month. During this time, it will not be possible to proceed with further types of work. Otherwise, quality and durability problems will immediately arise. When there are enough funds, you can purchase ready-made mixtures (quick-drying version) which you can use in your work.
It will not be superfluous to produce a layer of sound insulation under the concrete layer, especially if the audibility between the floors and the lower floors is at a high level. In this case, a reinforcement layer is added to the mortar so that the fill layer does not crack.
When a floor screed is performed for the subsequent laminate flooring, the fill layer performs several main functions at once:
- Leveling the base, which is also the primary task of the prepared mortar.
Masking communications and pipes that could create an obstacle to the normal creation of an interior in the room. In addition, a water or electric floor heating system can be placed in the screed.
- The roughing base becomes stronger and more reliable, capable of withstanding numerous external mechanical influences.
- Sound and heat insulation. At the same time, you should provide and buy the necessary materials for this.
- While walking on the floor, the load is uniform. The same applies to arranged furniture, interior items. It will be able to withstand even heavy schools without damaging the very floor covering that will be laid.
Each type of screed has its own list of materials and tools for work. This is due to the process itself and the technologies, which differ from each other.
So, for dry leveling of the subfloor under the laminate, you will have to buy not only plywood sheets or plates, but self-tapping screws, a hacksaw, a drill, a tape measure, and so on. Of course, all this is usually in the arsenal of a seasoned builder.
A screed from a prepared solution of sand and cement, with all the additives and components, will require you to buy another primer, a level (preferably a laser for accurate calculations), a rule of a certain length, a mixer, beacons to help leveling, a spatula, and so on. In this case, the mixture is prepared in advance before all work is completed. It is important to mix all the necessary components correctly, without deviations. Particular attention is paid to the amount of added water. Too rare a mixture will not be able to give the finished base strength, it will dry much longer, and most likely the whole will crack.
Recommendations for screed construction
It is very important to observe the proportions while preparing the mixture. The quality of the entire filling for alignment under the laminate will depend on this. Usually, all this is written on the packaging from the mixture, if this is a ready-made version. Otherwise, you should follow the recommendations from experts. There will be no strength for the slurry.
You also need to be able to work with self-leveling mixtures. Pouring and screed must be repeated on each site so that there are no holes in the subsequent. This is due to the fact that such a mixture tends to sag during drying. Moreover, it has a very high degree of fluidity.
At the end of the work, areas with subsidence may form, when even the lighthouses that have been exhibited earlier appear. To obtain a flat surface, the beacons are removed or, if possible, sanded until they are completely leveled. The resulting voids are sealed with the same solution. Until the mixture dries on the floor, do not move or perform other types of work. All this will only damage the surface and there will be no result from the work.
Making a screed from sand and cement
As mentioned earlier, the "wet" option for leveling the subfloor under the laminate requires attention and experience. There is even a sequence of work that will help you achieve the desired result:
Preparatory measures when it is necessary to take measures to remove dirt and dust from the surface. A construction vacuum cleaner will help with this.
The old coating is also removed if it has significant damage. A dry laminate screed can be applied to existing voids and cracks. They are being sealed. Before pouring the mortar, the surface is covered with several coats of primer to increase the adhesion level.
- To ensure that the mixture is evenly distributed over the entire area, beacons are placed. There are several options for this, each of which is different from each other. The easiest way is mortar beacons, which are not even removed later, but remain in the fill layer. Lighthouses are set by level, having previously determined the zero level in the room. A stretched rope, which also adheres to the existing level, can also act as landmarks. The exact method depends on the individual decision.
The solution prepared according to all the rules and proportions is distributed over the area in the room, starting from the corner farthest from the entrance. This is due to the fact that it is better to pull the excess mixture from there to the front door than in the opposite direction. Everything is done with an orientation to the pre-exposed beacons. The thickness of the fill layer will depend on the purpose of the screed, the existing initial rough base, the difference in floor level.
- Once the distributed solution has set and dries within the specified time, an additional layer of primer should be applied. You will almost never get a perfectly flat surface to start laying your laminate flooring. In this case, you should think about filling the layer with a self-leveling mixture.
But here it is worth remembering that one of the options presented is performed under the laminate (concrete screed or self-leveling layer). Everything will depend on the initial evenness. Self-leveling mixtures are used with floor height differences of no more than 20 mm.
It is one of the expensive options for leveling the sub floor.
It is very convenient to use and work with. The main thing is to prepare the base well, remove excess debris and dust, which can affect the quality of adhesion of the mixture to the base.
The mixture is ready to cope with such defects as cracks, chips, irregularities on its own. After pouring the mixture on the floor under the laminate, it should be leveled using a rule. All that remains is to walk with a needle roller to get rid of air bubbles. The drying process does not take much time, after which you can immediately start laying the laminate on the prepared substrate.
Dry leveling method
For laying the flooring, a dry floor screed under the laminate can also be selected. Most often, this is done on a wooden base, which is pre-checked for quality. If the boards are rotten and very old, it is best to replace them with new ones. Existing irregularities on the plank floor are cut or sanded off. Everything will depend on the condition of the surface. In some cases, it is easier to get rid of the old base and lay a new one.
When leveling, a sheet of plywood is laid over the entire area of the room. Laying is done towards each other, leaving a slight gap. If there are decorative elements in the alignment path, you can cut the plywood with a hacksaw.
Cement-sand slabs can be laid on the boards. Laying is done in the same way with plywood. Fastening is carried out using self-tapping screws. The evenness of the laying is checked using a building level, which can be purchased at any hardware store. Next, you can lay the laminate on a dry screed.
Another "dry" way of leveling the floor under the laminate is expanded clay. It is in demand due to its lightness, reducing the load on the floor slabs with significant height differences. At the same time, the strength remains at a height, it is able to serve for a long period.
In addition to the classical function, expanded clay has sound insulation properties, is environmentally friendly, and does not release harmful substances into the environment. This "cake" retains heat very well indoors. During operation, you do not need to worry that such a floor will start to rot, mold will form in it. The cost of the material is not high, but you can buy it at any hardware store. Laying the laminate on a dry screed is carried out in accordance with all the rules and requirements.
If there is no desire to independently carry out all types of work, then you can contact the specialists. They certainly know how to properly arrange the screed under the laminate flooring, and which one to choose for high-quality alignment.
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