Installation of floor slabs is a technologically difficult construction phase, which has several important features. Without their knowledge, builders can make many mistakes, fraught with serious consequences.
Types of products and features of their choice
Today, two types of such products are produced - hollow and monolithic. Each of them has its own disadvantages and advantages, considering which it is necessary to choose structures for a particular structure. So, if the building is small, a monolithic product is not suitable for it because of too much weight, which will greatly complicate the installation of floor slabs. In addition, monolithic structures have low soundproofing and heat-saving properties, so they are rarely used in the construction of residential buildings, but in the construction of industrial and public facilities, these structures are indispensable.
Hollow products are appreciated for their important advantages: lower cost and light weight. But although the structures have a lower mass in comparison with full-bodied products, transportation and installation of floor slabs can only be carried out using special equipment.
Features of Hollow Canvases
The advantages of using hollow core slabs include reduced load on the foundations and walls of buildings. Moreover, this is possible regardless of the configuration of voids, which are round, polygonal or oval.
Tip: voids can be used for laying corrugated pipes, plastic ducts or cable channels.
Thus, the installation of prefabricated floor slabs is a guarantee:
- Good sound and heat insulation qualities.
- Longevity.
- High mechanical density.
- Fire resistance - internal cavities do not allow high temperatures, from which wood and plastic elements can ignite, to penetrate further.
The influence of the size of the plates on their installation
Currently, canvases are produced with a thickness of 22 cm, a length of 1.8 to 6.3 m and a width of 0, 99 to 1.49 m. The weight of the structure depends on the size and type (monolithic or hollow). Accordingly, the complexity of mounting a monolithic slab is higher than a hollow core structure of similar dimensions.
There are several other important points that you need to pay attention to before purchasing reinforced concrete products. You need to follow to:
- The constructions were as close as possible to the nominal size.
- On the surface of the products there should be no hollows, bulges, cracks, as well as greasy marks or rust.
- Designs had the corresponding certificate of quality.
Before you get started
There are several important rules of the technology for installing floor slabs, which professional builders are well aware of. Private developers may not even be aware of this, respectively, an additional mention will not be superfluous:
- It is necessary to lay the products so that their smooth side is turned down, and the rough side is up.
- Customize the canvas on their underside.
- Plates are laid close to one another, without gaps.
- The main rule for installing floor slabs is that the products must be laid so that they rest on the supporting walls with short sides. Long sides are not recommended for laying on the wall.
- Special equipment services are not cheap, so it is necessary to prepare everything necessary for work in advance, including inviting 2-3 assistants so that the installation is quick and smooth.
Note: before starting the draft work, it is necessary to fill, as far as possible, the voids in the expanded clay canvases.
Preparing for installation work
First of all, it is necessary to level the load-bearing walls so that they are as even as possible in height. The discrepancy in their surface can be no more than 1 cm.
To determine how smooth the surface is, you can use a regular beam. The accuracy of the result depends on the length of the beam - the shorter it is, the less accurate the result. Applying the beam as a building level, it is necessary to check all the walls that will be used as supports for the slabs. If any irregularities are detected, a designation is put on the wall in this place.
After that, the highest and lowest points are determined. Based on the data obtained, alignment is performed using a concrete mixture and a metal wire mesh.
An important detail: when preparing the solution, you need to be very careful and carefully sift the sand and cement so that not a single pebble gets in - otherwise the plate will lie incorrectly and the ceiling will turn out to be uneven.
If the walls of the building were erected from gas silicate, slag or foam concrete blocks, they need to be strengthened. For this purpose, you can use a reinforcing belt with a height of at least 0.15 m. This will help to avoid possible wall deformation and protect the floor slab from breaking.
Site preparation for the crane
This question is one of the important stages of preparation for the installation of floor and cover slabs: the quality of installation of the paintings and even the integrity of both the building under construction and nearby buildings, as well as the safety of people, depend on how correctly the work is done. In order for the crane to be securely fixed, it is allowed to install it only on compacted soil. There should not be houses under construction nearby with basements - the support of special equipment during work creates a huge load on the soil that the walls of basements can not withstand.
If the soil on the site is loose or loose, you need to rent a crane with the longest possible boom - then it will be possible to install the equipment further, where the strength of the soil does not cause concern. If the construction has to be carried out in the autumn or spring, when the earth is saturated with moisture, so that the special equipment does not get stuck in slush, a site is prepared in advance for its installation by laying the soil surface with road plates.
Performing a ruler of slabs
It is not recommended to lay one slab on two spans - it can crack, but if you had to do just that, then in order to avoid destruction when the building shrinks against the central part of the middle wall, it is necessary to make an incision on the slab using a grinder with a diamond disk. Depth of cut - to the depth of the disc. Then, when a crack occurs, it will go along the notch - and this is quite acceptable.
Sometimes, in order to fit the plates to the desired size, they have to be lined in length or width. To perform the work, use the following tools:
- Scrap.
- Sledgehammer.
- The grinder. A diamond disk is mounted on the tool for operation.
- The board or bar, which will be laid under the canvas under the line of the future cut.
Fit plates to the right size
First of all, markings are made on the upper surface of the canvas and the grinder is cut. Then they strike with a sledgehammer so that the plates are as close as possible to one another. Where the cut passes through the void hole, the blade will break very quickly.
Cutting the canvas in width will be much longer and more difficult, since you will have to cut off the reinforcement that comes across. To do this, you can use the grinder, but so that the disc does not “bite”, it is necessary to notch the rod completely, but leave a couple of millimeters, and then finally break it with a sledgehammer.
No matter how high-quality work was performed, the integrity of the plate is still violated. You can avoid this in the following ways:
- Follow the sequence of installation of floor slabs - start laying slabs on one side and finish work on the other. In no case do not start laying from two sides - even if everything is in agreement, it will not be possible to lay tightly on the connecting plate so that there is no gap between it and the adjacent reinforced concrete structures. This violates the tightness of the connection and the strength of the canvas.
- If the canvas is a little lacking, you can leave a void near the walls, which then lay in blocks, and then make a cement screed. In the event that the empty opening exceeds a distance of 30 cm, it will be necessary to make a coupler of reinforcement.
- Leave the distance between the plates themselves. Then the voids are closed from below with moisture-resistant plywood, the reinforcement is laid so that it extends beyond the upper edges of the slabs and the resulting formwork is poured with concrete. When the mortar dries, the plywood can be removed and a general screed can be made on top of the boards.
After installation is complete
In order for the future room to be strong and durable, a bundle of reinforcing bars of all installed elements is carried out. To do this, one end of each rod is welded to the loop on one sheet, and the other to the loop of the adjacent sheet.
Attention: it is unacceptable to connect several concrete products with one rod - only two adjacent structures.