Floor screed solution
When it comes to changing the flooring, quite often a situation may arise where you need to level the floor. Just the same solution for floor screed - this is one of the options for how you can make a flat base before you lay a coating on it.
Why do you need a solution
What is this mixture? A solution is a compound of a material with astringent properties, with filler and sand. With the help of the solution, you can not just raise the floor level to the desired level, but with the right sequence of work and accurate compliance with building codes, the floor can be easily leveled or given the necessary slope.
How to choose a proportion
Usually the ratio is considered only between solid materials, since water is added to the solution until the desired consistency is reached. The most commonly used proportion is 1: 3. This means that 1 measure of cement and 3 measures of sand are taken to mix the mortar. Such a measure can be a bucket, shovel, units of measure (kg).
The water needed for the solution is usually added in the ratio of 0.5 l per kg of dry cement. In this case, the brand of the resulting solution will be in the range of 150-200.
Note! The more water, the lesser the strength of the solution. Such a mixture can subsequently crack in one or several places and the coupler will have to be repaired or even redone.
How much you need to fill the screed depends on what thickness it decided to do. Also on the flow affects and the condition in which the base of the floor. In the case when the solution only needs to level the floor curve, its thickness becomes 2 cm. If some plasticizers are added, then the thickness may increase to 30 mm, otherwise cracks may appear.
This screed, made of cement-sand mortar, is also used to equalize differences between rooms or the difference in the level of the floor. In the case when the differential reaches a value of 60 mm or more, the problem tie may not be solved, since such thickness is unacceptable for it.
In the case when the base for linoleum or laminate is created by oneself, such question may arise - what solution is usually made to create a leveling screed? It is important to know that there are certain types of solutions used, although their components may differ, they all have one thing in common - the presence of cement as a binder.
The filler is usually sand, and sometimes various polymers or mineral additives can play this role, which can perfectly improve the characteristics of the solution. Each of these mixtures has its own unique properties.
Cement formulations
These mixtures are used most often, because they are practically not affected by moisture, and they can also be used in many types of premises. However, there is one drawback - cement formulations are able to shrink, therefore, if the thickness of the screed is less than 3 cm, it can crack. To avoid such a turn, it is necessary to lay a grid of reinforcing rods inside the tie.
Gypsum compounds
Also called anhydrite. Making it pretty easy; Moreover, such a composition freezes within 1–2 days. Unlike conventional cement mixture, this does not shrink and can be laid out in a thin layer. However, before starting work, the room must be dried, since the presence of high humidity has a negative effect on the strength of gypsum.
Both types of formulations are usually sold in hardware stores in packages. Also in their composition are modified additives that can make the kneading process a little easier, increasing its fluidity. Also, subsequently laying the floor covering on this base is noticeably easier.
Note! Acquired ready-made composition will be released more sensitively than cooked own hands.
Preparation of the solution
It is worth knowing that before adding sand to the solution, it is necessary to sift carefully. As a result of such sifting, it is cleared of such large fractions as pebbles or trash that fell during loading. If it is wet, it is worth waiting until it dries out.
Note! Alternatively, wet sand can be added to the solution, but then less water should be poured into it.
It is best to use cement having the mark M400. If the brand is smaller, the strength of the resulting solution will leave much to be desired, and it will not perform its task qualitatively. By the way, if you keep cement for a very long time, its brand decreases, that is, it loses its cementing properties. As a result, the brand of the entire solution will decrease. Therefore, to prepare the solution, it is better to take fresh cement, and not the one that has already been in stock.
Sometimes various plasticizers can be added to the solution. Their goal is to change the period of hardening of the screed, and also to improve the process of working in difficult conditions (high humidity, heat or frost, and so on). If the temperature in the room is such that the screed will dry extremely quickly, or even dry out, then plasticizers are used which slow down the hardening process. And in the case when it is necessary that the solution froze faster, other types of plasticizers are added to it. In addition to them, fiber may be added to the mixture, that is, a special polypropylene fiber.
If the solution is already mixed, you need to remember that it seizes in a couple of hours, and in the heat even faster. Therefore, it should be used immediately in full and should be aligned with the rule in the course of work, otherwise it will be impossible to do anything with it since it hardens. Dilute the frozen solution with water will not work.
How to mix components
It is best if dry materials are mixed separately before adding water to the solution. Where to begin? There are a number of steps that will help the beginning builder to make the solution correctly:
- To begin with, dry parts of the solution are mixed, as mentioned above. This is a cement with sand, if any, fiber is also added. If the cement has the required grade of 400, then the proportions are chosen 1: 3, that is, the sand is three times more than the cement. The dry solution is stirred until a homogeneous mixture in color.
- The plasticizer and water are mixed in a different container, and not in the total. In the case of a bag of cement weighing 50 kg, a plasticizer, you need to take only 190 g, and add a third of the water by weight of cement, that is, about 16.6 l, taking into account that this will take about 600 g of plasticizer on the plasticizer itself.
- After these two operations, performed separately, dry and liquid mixtures are merged into a common container and stirred together. If you try to stir them at the very beginning, it will not work.
In the container, which contains the mixed plasticizer, you need to pour water and add the dry mixture.
Note! If you pour the dry mixture into a container and pour water there, the dry material will be taken up in lumps, which will then be difficult to stir.
In order to preserve your strength and mood for a longer period of time, it is better not to make the solution manually. If there is such an opportunity, you should use a mixer or a drill with a special nozzle - the quality of the solution will be much better.
In general, the solution is prepared. Now you can proceed to the device screed.
Pouring solution
How exactly is the screed done? Even a relatively thin layer is poured over the lighthouses. This is especially true for rooms with an area of more than 15 m ?. In the role of lighthouses can serve as flat wooden slats, metal corners and square tubes. However, it is best to use the factory beacons, which are made specifically for pouring the floor.
Note! Lighthouses need to be fixed, otherwise in the process of pouring they may move and the level of the floor will fail. If you need to lay on the floor reinforcing mesh, then this is done before installing the beacons.
When the lighthouses are level, you can prime the floor and flood the screed. It is usually done in stripes to fill the line between two lighthouses. The finished series is leveled by a long rule. The most recent line is closed in front of the door - it is convenient and practical.
When the entire floor is filled, you need to wait about a day until the screed grabs. After that, you can gently remove the beacons and fill the gaps remaining from them with fresh solution. When the entire floor is dry, it will be possible to lay a coating on it, however, the first time (about a week) you need to water the drying solution with a small amount of water so that it does not crack.
Video
The video tells about the screeds on expanded clay pillow, as well as on the composition of the home-made solution for the spreading of expanded clay:
The video shows how to prepare a solution and what should be its composition for the finishing screed: