Polypropylene fiber for screed of warm floor

The need for a cement screed device as a base coat can arise for various reasons. Among them we can note the desire to make the floor base more even, to strengthen the overall design of the room or to create a "cushion" for heating flooring. In the latter case, the choice of auxiliary interlayers with the effect of plasticization is particularly justified. The very choice of means for improving the technical qualities of concrete is limited by tight laying conditions, not counting the inevitable reduction in the height of the ceilings. In such cases, screed fiber is used, which takes up little space in the coating structure, but at the same time gives it a number of positive performance characteristics.

General information on fiber for screed

To understand the principle of the structure of the fiber in the concrete screeds, one should first turn to traditional reinforcement. Metal bars of reinforcement are integrated into the basis of walls and ceilings in order to ensure high strength characteristics of the structure. To what extent this technical solution is justified, it usually depends on the quality of the rods and the concentration of their presence in the concrete base. In turn, the screed fiber is the same component for reinforcement, but acting with other technical qualities. As a rule, these are thin fibers made of plastics that are stretched and somewhat crushed during the manufacturing process. Here it is possible to draw a parallel between bulk admixtures in solutions, which serve as binders and plasticizers. The same cement provides a dense bond between the ingredients of the mixture. Similar functions are performed by fiber fibers, realizing also the task of strength reinforcement.

What is the difference between polypropylene fiber for screed?

In the general family of reinforcing materials, there are many options that are suitable for strengthening walls with ceilings, and for delicate introduction into finishing mixtures. Fiber can be attributed to small-format reinforcement, but it is not the only option suitable for screeding under the "warm" floor. There is also a metal fiber, which has its advantages. It is durable, more affordable and durable material. And here the question arises - why is metal reinforcement worse than polypropylene fiber? The solution for the screed under floor heating, in which there are steel fibers, has several disadvantages. First of all, the metal itself has the properties of electrostatics, which can create problems in the case of water floors, and when laying electric mats. Secondly, close contact of metal with plastic pipes entails undesirable chemical degradation reactions. Both of these drawbacks are completely devoid of polypropylene fiber, but at the same time, it corresponds to analogs for technical and operational properties.

Material specifications

In the composition of plastic fiber, as a rule, there is one component - polypropylene. The density of the material varies from 0.9 to 0.95 g / cm ³ , which indicates a sufficient quality of the stiffness of the fibers. It can not be said that it is comparable to the performance of the same steel mesh, but it is enough for a home screed. Moreover, the function of mechanical strengthening in this case is not so important. Dimensional characteristics are very diverse. So, the diameter of the fiber can be from 15 to 25 microns, and in length - from 6 to 20 cm. It is important to note that the screed fiber, in contrast to the reinforcement or mesh reinforcing layers, is often friable fibrous material, therefore, the standard sizes are conditional Character.

Performance properties of fiber reinforced concrete

Manufacturers of fiber tend to state two main qualities that can be achieved through the use of this material. It is durability and elasticity. After laying the solution, it takes a little time to harden, and after a few days the screed will effectively resist mechanical, chemical and other impacts. In addition, the fiber for the floor screed with preheating also prevents the natural processes of destruction of concrete as such. Practice shows that the addition of polypropylene fibers to the solution reduces the probability of delamination of the cement structure, the formation of cracks, chips and shrinkage defects. Floor heating systems are not recommended for use in rooms with high humidity - for example, in the bathroom or in the kitchen. However, reinforcement with polypropylene makes concrete waterproof, so the risks of negative impact under such conditions are significantly reduced.

The rate of fiber consumption

The universal proportion that would fit in each case does not exist. Select the optimal ratio of solution and fiber should be based on the requirements for screed. The minimum volume is 300 g / m ³ . In this case, external characteristics of concrete will manifest themselves - for example, the binding function will improve and in general the work with the solution will be facilitated. But in the long term such inclusion will not be effective. The average volume is already 600 g / m ³ . In this proportion, one can expect to achieve the properties of plasticization, the same water resistance and elasticity. If there is a question about how much fiber to add to the screed from the calculation of the area, then the average rate can be considered 30 gr per 1 m ² with a coating thickness of 3 cm. And here we must bear in mind one more aspect - will the increase in the concentration of fiber In the structure of concrete? As in the case of conventional fittings, exceeding the content of additional components in a concrete base can provoke internal stress. Thus, it is possible to achieve the formation of cracks and splits.

Preparing for reinforcement

Preparatory work is carried out on general principles. The site on which the concrete base will be constructed is cleaned of debris, dust and foreign objects. In this case, the roughing surface itself should not have serious defects. If they are available, use primer and trowel mixes. The coating, on which the solution and fiber for the screed will be laid, should be not only clean, but also smooth. Further, wooden or plastic beacons are arranged, forming in some way the contours of the formwork. In the formed boundaries, the base of the screed will be arranged.

The order of performance of installation works

Work begins with the preparation of the mixture. At once it is necessary to notice, that the home coupler for a floor with heating is better for fulfilling on the basis of portland cement. If necessary, other plasticizers may be included in the dry mass preparation stage. At the same stage, before filling with water, the fiber for the screed is also introduced, the consumption of which, as already noted, is calculated in the proportion of 300-600 g / m ³ . The mixture is then thoroughly mixed and filled with water in accordance with the instructions for the use of cement of a particular brand. After bringing the mixture to the optimum state by stirring, it is possible to fill the prepared area. Again, the thickness of the layer can be 3 cm, and all 10 cm. This depends on what type of floor heating system is used. After this, the finished product should be re-mixed with a vibrating sealer. At the final stage, the screed is leveled and it remains to wait a few days so that it can obtain the necessary characteristics.

Conclusion

The floor heating system itself is a rather complex component, from the point of view of the introduction of a concrete screed into the mass. It should be understood that, depending on the type of its functional elements, there may be a need for additional operations - for example, the inclusion of insulation layers. In turn, the fiber for the screed of the "warm" floor not only strengthens the concrete mass, but also serves as an assistant in the distribution of heat. It is thanks to the unique effect of spatial micro-reinforcement that this filler allows evenly distributing the properties of the screed structure throughout the site. At the same time, the internal physical processes of concrete do not adversely affect the quality of the heating system.