How To Properly Pour A Cement-sand Mortar To Level The Floor

2023 Author: Philip Bishop | [email protected]. Last modified: 2023-08-25 07:54

• Training
• Waterproofing
• Exposing lighthouses
• Reinforcement
• Solution components
• Fill rules
• Types of expansion joints
• Seam cutting locations

Before you start laying any kind of floor covering, you should consider carrying out a high-quality leveling of the base. This is why the screed technology in the apartment was created. It provides for the implementation of sequential activities, the quality of which will determine the final result. After the completion of the installation work, you should think about the device of expansion joints, which can be of various types. Each of them performs specific functions.

Training

All work on the installation of floors in the apartment should begin with preparatory measures. After a thorough inspection, all points must be completed on the surface so that the installation of the floor screed can be started.

First of all, it concerns the removal of excess debris and dust. This is carried out in parallel with the removal of irregularities, protruding elements that may interfere with the pouring of the solution.

In the presence of cracks, potholes, pits, all of them must be sealed with a specially prepared mixture. Large-volume base defects are filled with a solution of sand and cement, which is prepared in a strict proportion of the components.

The initial measures should be attributed to setting the "zero" level and all other points relative to the horizontal line. The quality of these works will affect the evenness of the future concrete floor. At the same time, the technology of flooring in the apartment must be fully observed. Any deviations will negatively affect the bottom line. The installation of a concrete floor in an apartment provides for sequential work.

A certain set of tools and materials will come in handy in the work. Everything will depend on the specific situation of installing the concrete floor, as well as on the desired quality and strength of the solution. Each of the items can be purchased at a hardware store without any problems. If desired, you can use the services of special construction equipment, which is rented for a specific period together with the contractor.

Waterproofing

Before preparing the solution for pouring the floor, the main stage should be completed - the device of the waterproofing layer. This is especially true for premises in private households, when the flowing groundwater is very close. Waterproofing will prevent the ingress of water from the soil into the poured solution, which can cause oversaturation with moisture and uneven drying. The same applies to the rapid release of water from the fill to the lower floors and rooms. If this layer is not completed before the installation of the concrete floor is carried out, this will adversely affect the drying process of the solution, the final quality and reliability of the surface of the future floor.

The floor screed technology in the apartment provides for the use of a certain set of materials for the waterproofing layer in the work. These include:

1. Roll waterproofing. The most common of them is roofing felt. But it has a vulnerable area, which is the joint of the sheets. This suggests that they should not be joined, but have an overlap of at least 15 cm. Some rolls on sale have a special fastening element along the edge, which allows individual sections to be fully and reliably connected to each other.
2. Liquid waterproofing. Bituminous mastic is one of the most expensive. But in the end, they provide an excellent result, with which almost nothing can compare. Perfect for rooms with high humidity, which can be bathrooms.
3. Waterproofing film. Cases of using ordinary polymer films are not uncommon. It should only have a certain thickness in order to meet all the qualities of the layer being arranged.

The choice of a particular option will depend on the size of the wallet, the desired positions, as well as the specific case and the state of the premises as a whole.

Exposing lighthouses

Certain floor screed methods provide for additional measures for leveling the base using a cement-sand mortar. This includes floor beacons. There are a huge number of options for them: profiles, concrete embankments, self-tapping screws, tensioned threads, etc.

In this case, it is worth paying attention to the fact that they are firmly and reliably fixed to the base before pouring, and also can successfully withstand the loads of the volume of the solution on the site.

If the beacon for pouring the floor is made from a beacon profile, then it is fixed on the surface, on an embankment made of concrete mortar. Lighthouses should be located exactly in accordance with the marked horizontal lines relative to the floor level, as well as depending on the height and thickness of the flooded area. On the top of the exposed beacons, it will be necessary to carry out a rule or other tools for leveling the cement mixture.

Reinforcement

A screed device in an apartment cannot do without a reinforcing layer. It allows you to create a sturdy structure that can withstand maximum loads. But here it is worth paying attention to the choice of a specific material for work. Most often, a steel mesh is used, which fits into the thickness of the future screed layer.

A large amount of reinforcing agent in the mortar can lead to increased stress on floor slabs or other base materials. This is especially true for older buildings. There are permissible loads that you should adhere to.

When choosing the floor thickness, as well as the quantitative composition of the reinforcement layer, it is worth looking closely at the old screed.

When it is destroyed and dismantled, the layer, the reinforcement material used and other points are approximately calculated. But these are only indicative figures.

To make the installation for pouring the floor, together with the reinforcement, strong and at the same time suitable for operation in accordance with building codes, together with metal elements (rods, mesh), a more modern material is used - fiberglass. It gives the solution plasticity and better qualities during the drying process. You can practically forget about the process of shrinkage of the pouring, the appearance of even microcracks. Fiber is able to eliminate these defects and at the same time arrange an excellent reinforcing layer. There are several options and types of this material. When choosing each of them, the amount (weight) in work will depend on each square meter of the room area. But in any case, the cost of fiberglass will be slightly lower than the purchase of steel mesh or other metal products.

When it comes to metal structures as a reinforcing layer, then they should not be located immediately on the base. This will not be able to bring any effect. The mesh or rods must be fixed with special elements at a certain distance from the lower section in order to be located in the middle part of the future concrete floor. All this is provided by the technology of pouring the floor screed in the apartment.

It does not matter with what solution to make the floor screed, the main thing is to correctly perform the layer of reinforcement. It will give the whole "pie" reliability and increased service life.

Solution components

Many probably know how to make a floor screed mortar. But still, this should be done efficiently and observe the proportions for the floor screed. All the components used, as well as possible impurities and additives, must be uniformly combined in the filling. Only this will ultimately bring the desired result and the strength of the entire layer of the concrete floor.

Floor screed mortar has certain requirements. The binder in it is cement, and sand acts as an aggregate. The basis of everything is water. It is for this reason that it is required to take it clean, not contaminated (without acidic and oily impurities).

There should not be any other rocks in the sand. The same applies to clay, which will only bring negative to the future prepared solution. The grade of screed mortar will depend on the grade of cement used. It is recommended to use it not lower than M400, so that the strength is the best. When choosing a cement, you should pay attention to the period of its production and shelf life. It is not uncommon for sacks of cement purchased a long time ago to be placed on the shelves. After all, it has the properties of caking, losing its properties and qualities. The brand of the floor screed must match.

When preparing a solution for pouring a floor, proportions play an essential role. The most optimal option would be 1 proportion of cement to 3 proportions of sand. Water is added in the required amount. The solution should not be too thin or too thick. All this will create problems when installing a concrete floor.

When mixing especially large volumes of mortar, it is best to use a concrete mixer. It allows you to mix all components evenly without unnecessary labor. Various additives can be added to the composition of the floor screed solution, giving it certain properties. In the same way, you can change the color of the solution if necessary.

During the preparation of the cement mortar for the floor screed, the proportions of each component must comply with the requirements and established standards. Much will depend on the cement used, its brand.

Fill rules

After the mortar for pouring the floor has been prepared, you can proceed to the direct pouring of the future subfloor. All work begins from the far (opposite) corner from the entrance to the room. The finished mixture is poured, after which it is leveled using special tools. This may be the usual rule.

It is worth paying attention that the cement mortar for the floor screed is not overexposed. The usual time during which he retains 100 percent of his qualities is only 20 minutes. Subsequently, the cement mortar for the floor screed begins to gradually lose its properties.

The installation of the concrete floor should be carried out immediately after the mixture has been prepared.

Only in this case the filling technology will be followed and the desired result will be obtained. After the entire area in the room is filled with a solution, without missing a single gap, it is necessary to give it time to harden. This usually occurs within the first 12-18 hours. Further, you can smooth out all possible defects, wipe them, remove the beacons, filling the voids with the prepared mixture.

Types of expansion joints

During the operation of buildings, it shrinks due to temperature fluctuations, different thicknesses of the concrete floor and other errors in work. The same applies to the poured concrete floor, which may crack as well as it dries. To avoid all this on a concrete floor, expansion joints must be mandatory. Although this is not provided for and is not spelled out in building codes and regulations.

There are the following types of expansion joints in concrete floors:

1. Insulating. They are carried out along the walls, possible decorative elements in the room (columns), around the foundation ledges for the equipment. These seams are designed to exclude the transfer of deformations to the screed from the structure itself.
2. Structural. They are made out in those places where the day's work on pouring the solution has been completed.

3. Arrangement of shrinkage joints for concrete floors. Avoids the appearance of chaotic cracks on the screed during the drying process. If cracks appear, then only in a given direction. This is achieved by creating straight planes of slack.

   

Seam cutting locations

Depending on which seams are used in the floor screed, the place of their cutting will also depend. So, the shrinkage seams are cut along the axes of the existing columns and must converge with the corners of those seams that go along the perimeter of the structure. The distance to the seam from the column must also be clearly marked. It should not be more than 24-36 times the thickness of the poured screed.

This type of seam is also made on external doors and corners. Avoid the appearance of areas on the screed with sharp corners. There is already a huge chance of cracking. This will require the subsequent repair of joints in concrete floors.

There are certain requirements for slicing on hot days. Every third (or fourth) seam is cut before intermediate seams are made.

Structural joints, as mentioned earlier, are made in the event that there were breaks in the pouring of concrete on the site. They are made at the boundaries of these sites. Different cutting tools and equipment are used in each case. For each of them there are recommendations from the manufacturer on the correct cutting, which should be followed.

Cutting seams is performed immediately after pouring the mortar on the surface in the room or until the required strength is obtained. You can first make a test seam, from which you can already build on the device for further ones.

The seam cutting depth should not be more than a third of the entire screed thickness. It is in the direction of the resulting seam that all cracks should appear. No chaotic elements should arise.

If you adhere to the instructions and technology for pouring the concrete floor, you don't have to worry about the result. It will always be of high quality.

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