Recommendation points
- Types of screeds โ how to choose the right one
- Screed mixture
- Preparatory work
- Solution pulling
- We bring the process to its logical conclusion
The most affordable way to perfectly level the surface is to fill the screed. The technology of the process is quite simple and even a novice builder can do it. A high-quality do-it-yourself screed will result in a flat floor suitable for laying any type of floor covering.
Types of screeds โ how to choose the right one
Before you start pouring, you need to decide which type of screed is right for you. The following factors influence the choice of screed:
- features of the existing base;
- functional purpose of the room;
- the desired level of heat and waterproofing;
- top coat of screed.
In apartments with floor slabs, a knitted screed is performed, when the solution is poured onto the existing concrete base without additional intermediate layers. Such a screed can withstand heavy loads and is easy to use. Minimum thickness of knitted screed laying โ 30 mm.
It is recommended to install a waterproofing screed in the bathroom and kitchen. In this case, the solution is not bonded to the base, but is laid on an intermediate waterproofing layer (film, coating or roll materials).
The heat-insulating layer in the screed device is appropriate in rooms with a basement or other unheated rooms below. Expanded polystyrene, mineral wool or bulk materials are used as insulation.
All screeds with interlayers are called floating. This is a separate design, not related to the existing coating. To ensure the strength of the floating floor, it is imperative to lay a reinforcing mesh before pouring.
Before starting work, it is necessary to correctly plan the thickness of the future screed. It depends on the strength of the existing floors, the design of the screed itself, the expected load on the screed. For example, when leveling floors on a balcony, the permissible screed thickness is 40 mm. Otherwise, the overlap may not withstand. The screed on the warm floor is poured with a layer of at least 30 mm above the pipes, that is, the total thickness will be 50โ70 cm. In the case of a rough screed with subsequent installation of self-leveling floors, a layer of 20 mm is sufficient.
Screed mixture
The building materials market offers a variety of screed mixes. The simplest one (cement + sand + water) can be made by yourself. This mixture will cost you less, but its mechanical characteristics are far from ideal. Firstly, it dries and stands for a long time. Secondly, lace from cracks often appears on the surface. It is advisable to use such a mixture for a rough screed..
Modern ready-made screed mixtures are also mainly made on the basis of cement and sand or gypsum. To increase their mechanical characteristics, various additives are added to the composition. Such mixtures dry quickly (within a few days, and sometimes hours) and are strong enough.
Laying a two-layer screed involves a rough layer and a finishing (bulk) layer. In this case, it is possible to use mixtures of different composition and it is important that they are compatible with each other. The sequence of different component layers also plays an important role. So, gypsum screeds are not placed under cement screeds. Gypsum is afraid of moisture and loses its properties, and the cement slurry is very moisture-consuming. If the gypsum layer will be the finishing one, the cement rough screed must be primed.
Advice.When laying the screed in two layers, it is recommended to use mixtures on the same basis..
Preparatory work
As in any construction process, work on the screed must begin with cleaning the work surface. First, remove the floor covering, remove debris, dust and dirt. Sometimes it may be necessary to completely dismantle the old screed. This job is dusty and time consuming. Perform it with a jackhammer or perforator.
If the screed provides for a waterproofing layer, then it is laid first after cleaning.
Beacons are installed on the cleaned surface. This is a very crucial stage, on which the correctness of the screed performance depends in the future. Beacons can be metal or wooden slats. Profiles for drywall do very well with this task..
For marking for beacons, first of all, you need to determine the highest point of the floor using a water or laser level, from which further markings are carried out along the walls. The first lighthouse is installed 20-30 mm from the wall in level. For this, small piles of cement or plaster mortar are laid out at a distance of 800โ1000 mm from each other. The rail is slightly recessed in the solution, adjusting its position with a level. The distance between the beacons depends on the size of the existing rule. So, with a rule length of 2000 mm, beacons are installed 1800 mm from each other. It is important that all beacons are โin levelโ with each other and separately. After laying the beacons, you will have to wait for the retention solution to dry.
Advice.The installation of lighthouses can be carried out on alabaster. It grabs instantly and saves you time.
Reinforcing mesh is laid between the beacons after their installation.
Solution pulling
Filling the screed is a rather painstaking task. This requires strict adherence to the sequence of the process..
1. Before pouring the solution, the surface must be primed or moistened with water. This will improve the bond with the solution..
2. Mixing the solution. If you are mixing the mortar yourself using cement and sand, it is important to keep the proportions correctly. They depend on many factors, but the brand of cement is fundamental. In apartments and private houses, cement grade 500 is used in a ratio of 1 to 3. The ready-made mixtures are kneaded, strictly following the instructions, achieving a homogeneous mass of the consistency of thick sour cream.
Advice.Do not immediately knead the entire volume of the required mixture. She can dry out and lose her qualities..
3. The solution is poured from the far corner of the room in small areas so as not to step on it when leveling.
4. The poured solution is leveled by the rule, passing it along the lighthouses in the direction from the wall towards you, pulling off the excess.
5. Simultaneously with broaching the solution, the rule is to perform light tamping movements, expelling excess air. So the mixture will be evenly distributed, filling all the voids..
6. Step by step fill the screed throughout the room
We bring the process to its logical conclusion
A day after pouring, the screed will already grab and it will be possible to walk on it. Now you can remove the beacons. They have already fulfilled their function. The grooves from the lighthouses are sealed as follows:
- Fill the grooves with the harness. This semi-dry mixture is easy to prepare. You need to take cement and dry sand 1 to 3. Mix well. Make a well in the mixture and add water. Wait until it is absorbed. Add more water if necessary
- Wipe the poured mixture on top with a scraper to a level with a screed.
Gartsovka will bond well with fresh mortar and will not crack at the joints.
No matter how diligently you stretch the screed, traces of the rule and other irregularities will still remain on its surface. They need to be cleaned off. To do this, use the same rule or brick until the solution has gained strength.
At this stage, the do-it-yourself screed device can be considered complete. Now you just have to be patient and wait until it is completely dry and gain strength to lay the flooring. The screed dries for a long time, and the peak strength is reached only after a month.
Pouring screed is a laborious process that requires precision, diligence and patience. But the resulting perfect floor is worth it.
Would anyone be able to provide a step-by-step guide on how to make a floor screed? Iโm interested in doing it myself and would appreciate any tips and advice on the process. What materials should I use and what are the key points to consider while doing this project? Any personal experiences or recommended resources would be helpful too. Thank you!