Thickness of floor screeds: recommendations of specialists

Thinking about what the thickness of the floor screed should be, you need to consider many factors. Do not assume that a more impressive thickness will make the design better. This is the sin of many home masters who do not have the relevant experience. In practice, it turns out that the final strength of the fill does not always depend on the thickness, because the drying process can go wrong, for example, it will last several months, in this case the screed will not reach the required characteristics. In order to achieve the desired result, it is necessary to make an accurate calculation.

Optimum thickness

Aligning the sexes is a very important process, they are neglected very rarely. This is especially true for living quarters. As an exception, it may be the laying of the finish coat on the logs. The thickness of the floor screed for the heated system will then differ from the usual 40 mm fill. If you plan to lay water pipes, then you need a 70-mm layer, but the thickness of the screed in this case should not be more than 100 mm. If we are talking about an electric heat source, it can be hidden under concrete, the height of which will be 5 cm or less.

After pouring the solution can not be heated by the method of running a warm floor, because the strength of the screed will be reduced. As a basis for these figures are the requirements for the strength of the fill. Specialists recommend using more precise parameters for the screed. Thus, the thickness of the screed above the water warm floor can be equal to the limit of 7 to 10 cm. As for the electrical system for heating, the thickness can be 3-5 cm.

For reference

The hardening time of the largest thickness can reach 140 days. The system must be pre-tested for integrity and operability. This is especially true for water-pipe pipes. The system starts once more close to the completion of the solidification process, so that the moisture remains in the depth of the concrete are finally dried.

Minimum height of the screed

If you follow the sanitary rules and regulations, then in residential premises, you should fill the mortar with a layer of 40 mm and higher. This indicator is minimal. But in some cases it is possible to form a thinner layer. This can be attributed to the low activity of the operation of the premises, as far as ancillary and storeroom, because their visits are very rare.

If the thickness of the floor screed is less than 30 mm, the strength of the material may not be sufficient in unforeseen situations. This concerns the falling of massive objects. From this it follows that the minimum height is limited to a parameter of 35 mm.

It is important to pay attention to exceptions. If there is a purpose to increase the heat and sound insulation qualities of the flooring on an uneven ground, it is necessary to form a padding for easy screeding. On the unevenness of the board, a solution is poured, the thickness of which is 2 cm. After the material has dried, a heater or soundproofing is laid on top, then a separating thin film is placed. At the final stage, a solution of the calculated thickness is poured in order to ensure normal strength.

Features of the determination of the thickness of the screed

Before you determine the thickness of the floor screed, you must determine the conditions under which the premises will be used. Therefore, to some extent you can determine the operational load on the surface. For example, public rooms such as hallways, corridors, kitchens and living rooms require a significant layer thickness of 70 mm or higher or reinforcement, with which the height of the formation can be reduced to 40 mm.

If we are talking about a children's room that will combine the playing space, it is important to achieve an impressive strength of the coating. The thickness of the screed in this case should be 50 mm. If you take into account the above-mentioned approximate parameters, the question arises of what is the maximum thickness of the floor screed for the whole apartment. The answer to this question is unambiguous - the height of the layer should be the same everywhere.

In some cases, the difference in height between rooms or within a single space is created artificially, but this option can not be called the easiest. If you are building a floor heating system or want to achieve high strength of the base for the finish coat, then you should stop at a thickness ranging from 50 to 60 mm. This will be enough, which is especially important for the reinforcing layer. For calculations, doorways should make a guideline. After all, if you strongly raise the floor taking into account the finish coating, you can reduce them in height, which will require the installation of door leafs of unusual sizes.

In addition to the minimum parameters for the thickness of the screed

Some experts believe that there is no optimal thickness of the floor screed in the apartment. This belief is based on the fact that the mentioned parameter will depend directly from several factors, among them:

• A kind of overlap;
• Type of soil;
• Purpose of the room.

All these conditions influence not only the final index of thickness, but also on:

• cost of work;
• Type of reinforcing mesh used;
• Choice of brand of cement.

Based on the height of the concrete layer, it can be argued that the screed can have the following varieties of thickness:

• Minimal;
• Average;
• The maximum.

The minimum thickness sometimes reaches 20 mm. This type of coating can be equipped without the use of reinforcement, but only if self-leveling mixtures are used for work. The average thickness reaches 70 mm. In this case, you must use a reinforcement or reinforced mesh. The maximum thickness is 150 mm. In this case, the screed has the appearance of a monolithic construction with reinforcement. This option for a private home can act as a floor and a foundation, which are combined into a single system.

The thickness will depend on the materials that you intend to use when arranging the system. For example, a layer of concrete with crushed stone can have a minimum thickness. For thin screeds, the most suitable choice is self-leveling mixtures for finishing the floor. At the final stage, such a surface is covered with decorative material. With the help of such technology, it is possible to achieve the formation of an ideally flat, non-thick layer, after drying of the materials, it is possible to proceed with the installation of the decorative coating.

The thickness of the screed over the warm water floor is also determined by the diameter of the pipes. If the diameter does not exceed 25 mm, then a layer of 50-70 mm will suffice. Experts believe that for normal operation of the system and good warming up of the room, the thickness of the screed over the warm floor can be 4 cm. If the screed is higher, the thickness will complicate the regulation of the supplied heat, because a huge part of the energy will go to the heating of the concrete.

What you need to consider when arranging screed with a minimum thickness

Having familiarized yourself with the sanitary norms and rules, you can understand that the smallest thickness of the screed can be equal to 20 mm. However, in this case it is necessary to take into account one feature. Depending on what material is used, the height of the layer can be different. If the screed is formed on the basis of metal cement, then 2 cm will be enough. If you do not plan to use the reinforcing mesh, then the minimum thickness can not be less than 4 cm. This is because the lower layer height will not be able to provide wear resistance and sufficient strength of the coating.

If the minimum thickness of the floor covering is provided, you must observe several conditions, among them:

• Leveling the surface with a screed;
• Presence of rough floor;
• Absence of fittings and pipes.

If it is a question of placing technical purpose, then the most thin concrete layer can not be used, because the surface will be subjected to increased load.

In addition to the thickness of the screed system of the water-heated floor

A warm water floor is a system of heating elements - pipes that are filled with water. They should be located throughout the floor area. Typically, such a system is placed in a cement screed to protect against mechanical stress. It is important in this case, the maximum correct calculation of the thickness of the screed for the water-heated floor. This will ensure the normal functioning of the system.

The thickness of the screed is a pledge of mechanical strength and proper working capacity of the system, as well as effective heat transfer and economy. If you build a thick screed, it will have a large heat capacity, so the temperature will be much more difficult to adjust. Screed under these conditions heats up much longer, however, and the heat gives away a long period of time.

By laying a screed with a smaller thickness, you will get a floor that heats up in a short time, but this design can overheat and crack, heat transfer will go in strips that are limited by the pitch between the pipes under the floor. Choosing the thickness of the screed for the water-heated floor, you should take into account that this parameter determines the degree of protection of the pipeline and ensures an even distribution of heat over the surface.

The total thickness of the screed for a dwelling should not be more than 100 mm. If we are talking about pavilions, car centers and warehouses, then this parameter can be 200 mm or less. The thickness of the screed reaches 300 mm only in aviation hangars. The minimum thickness for laying the underfloor heating system is 65 mm. The thickness of the screed on the water heat field should be equal to the limit of 20 to 50 mm. If the structure is hanging, then a heat and soundproof layer should be laid between the pipeline and the base, then the thickness of the screed will be 35 mm.

Pour the screed onto the floor heating system

Once you have determined what is the thickness of the screed of the warm floor should be, proceed to work. The base is cleaned, because the dirty overlap will not be able to provide the required degree of adhesion. On a clean and dry surface, you should walk a primer mixture in 2 layers. To calculate the volume of the screed, you must determine the thickness, multiplying by the area of the room. For residential and domestic rooms it is recommended to lay screed within the range from 65 to 70 mm. The layer above the pipes will be 45 mm, while the thickness of the screed under the warm floor of the water will be approximately 20 mm. If you use mixtures for self-leveling floors, you can reduce the thickness of the layer to 45 and 25 mm, respectively. This is due to the fact that such mixtures have a higher density.

Experts do not recommend much to save on the thickness, because in this case, the floor can react negatively to unforeseen loads. If you plan to install large objects in the room, then reinforcement of the upper layer with a metal mesh should be provided. You can use it point-wise or across the entire area. In order to strengthen the screed, you should use solid additives such as fiber or chips from polypropylene. The first one allows to get a mixture called fiber concrete.

Selecting an impressive thickness of the screed of the warm floor, you will expect the layer to harden to 1.5 months. Before you start laying the finish coat, you must wait for the dryness of the base. In this case, the floor is more convenient, because it is characterized by rapid polymerization.

On the peculiarities of laying screeds

If you decide to fill the screed for the water-heated floor, the technology of the work will differ only in the presence of damper seams. If it is a question of placing in 10 m ² , the seams will be located along the enclosing structures. A special strip of depreciation should be located along the bottom of the wall. In the future, this will compensate for the expansion of the material when exposed to temperature.

When the room is more spacious, additional seams will be required. Among the functions of the damper tape is not only compensation, but also thermal insulation from the walls, because the coating has a thermo-repelling foil. In order to achieve a positive result, it is not sufficient to correctly choose the thickness of the screed on the water heat field. It is also important to check the operability and hydraulic density of the system. It is necessary to ensure the presence of a heat-reflecting layer under the pipeline in order to avoid heat loss. To choose the materials for the screed should be approached as responsibly as possible, this is relevant for cement, which is crooked if stored incorrectly and for a long time.

Conclusion

Before the beginning of the floor leveling, you should definitely determine the thickness of the screed of the warm floor. This parameter depends not only on the wishes of the user, but also on the structural features of the building, the properties of the floor, the power of the floor, the facing materials and other factors.