Cement screed - features of technology

Screed is the base for floor covering. Its use is dictated by the need to level the floor surface before finishing. Also, the screed is designed to give the base a specified angle of inclination and masking of various engineering utilities. In addition, it gives the surface the necessary degree of rigidity and regulates its heat build-up. The screed can be laid directly on the base of the floor surface, as well as on various auxiliary layers. For example, heat or sound insulation.

The most common now is a cement screed as the cheapest and most reliable way of leveling the basic surface of the floor. The basis for this type of screed is portland cement (hydraulic cementitious form of the cement mixture based on calcium silicates) and aluminate cements. As a filler, as a rule, a sandy component or gravel is used.

Cement screed should have a thickness of at least thirty millimeters, otherwise the risk of its peeling off the surface is great. The time for complete drying of this type of floor for flooring is about twenty-eight days. But in the end it turns out to be perfectly flat and very strong surface.

The device of cement screed has some specific features. To prevent further cracking and peeling, the hardening of such a screed should occur in conditions of high humidity. To this end, the wet screed for a period of up to seven days is covered with a polyethylene film, after removal of which it is recommended to fill the surface with wet sawdust and during the seven-day period, regularly water it. Cement screed, to which this approach is applied, after full drying will have excellent performance and durability.

The upper limit of the finished base surface should be lower than the floor level for the thickness of the intended floor covering. The very same cement screed is laid on special parallel beacons, which are designed to ensure a perfectly flat surface. The interval between the slats should be approximately one meter. Prepared cement mortar is placed evenly between the slats in a uniform layer. After packing, the beacons are carefully removed, and the space that has been freed is filled with a solution and leveled.

Another way to level the floor surface is dry cement screed. It is not so widespread yet, although it is cleaner, faster and less labor-intensive. The very principle of dry loose floor has been used for a long time. But recently, in the light of the emergence of new, relatively cheap materials, this technology is becoming more attractive and in demand.

The principle of this type of screed is to add polypropylene fiber to the cement slurry, which, evenly distributed in the mixture, reinforces it throughout the volume, which significantly reduces the microplastic shrinkage and prevents the formation of cracks during the hardening process.

This screed has many advantages and advantages, among which we can mention the speed of the work, its relatively low labor input, very fast drying and minimal shrinkage.