Installation of floors is carried out according to certain requirements, since the strength of the entire structure of the house depends on this. Some rooms also take into account water resistance, gas tightness and fire resistance.
In any case, the choice of the type of overlap is based on preliminary calculations, since an incorrectly made design in the future not only means failure, but also poses a threat to the lives of people living in such a building.
Features
The strength of all floors is calculated according to the constant load, which is determined by the weight of the house structure (the part that is higher), the mass of furniture, equipment and people living. Therefore, the closure of the attic space can be facilitated, and the basement or first floor must have a reinforced system.
It is worth considering whether the attic floor will carry an additional load and whether it is planned to make a frequently operated room there in the future. Also, according to SNiP, it must have very good thermal insulation.
Overlappings between floors are calculated by such indicators as strength and bending, and also provide them with the required heat and noise insulation. According to fire safety standards SNiP, in wooden buildings or partially wooden structures, the ceiling of the first floor should be made of non-combustible material, and the attic should be strong, because no wind vibrations should occur during wind loads.
In addition to strength, special attention should be paid to sealing joints, because the bulk of the heat loss of the building is through the roof.
Monolithic
Overlapping is carried out by pouring concrete into the formwork, which can be removable or non-removable. An advantage of this type can be considered unnecessary to close up the seams, also a characteristic feature is increased heat and noise insulation. However, this is a long and laborious process.
Firstly, the bottom should be covered with plywood, then reinforcement should be made over the entire volume, the large formwork should be driven out, and only then proceed with concrete pouring. At the same time, the cement grade should not be lower than 400. To carry out the next stage of work, you should wait about a month, it is during this period that the concrete will fully consolidate.
Therefore, high-rise buildings are not built using such technology. Monolithic ceilings are done in basement floors and rooms with high humidity. Most often, in two-, three-story frame buildings, the lower level is erected by this method, since overlapping with poor insulation contributes to the development of fungus and mold throughout the house.
Beam
Beams can be metal, wooden or reinforced concrete structures. That is, they bear the main bearing load (which is calculated for the entire floor area of this level), and between them the space is filled with structural material.
Tree
The overlapping of the first floor on wooden beams should be additionally treated with antifungal and fire fighting agents. Sections must be left beveled and insulated with roofing felt. The floor frame can be made open at the ceiling level of the lower floor. It is very beautiful because wood is a natural and environmentally friendly material.
Such a ceiling is erected in low-rise buildings, the weight of the structures allows you to do them manually. However, when choosing wood, you should pay attention to its percentage of moisture. All construction, and especially structural elements, are selected according to certain requirements given in SNiP.
Metal
This type of flooring is more durable, able to withstand heavy loads, and the building is installed relatively quickly. However, the specific gravity of such products implies the presence of machines and mechanisms at the construction site.
Designs can cover quite large spans (up to 8 meters), they are non-combustible, but require mandatory heat and sound insulation. If the floor system is made of metal (channel, I-beam, etc.), then the voids are most often filled with structural plates, after which the surface is filled with fine slag and a cement screed is made.
Hollow core slabs have characteristic advantages:
- Reduce the specific gravity of the structure.
- Thanks to voids, they have heat and sound insulating qualities.
The use of such products is necessary in order to level the floor, because floor slabs have a certain height difference. This process of erecting partitions is carried out for buildings with a full and incomplete frame. For example, when in a two-level apartment the upper tier is smaller in area than the lower. In addition, if possible, it is recommended to make a cantilever design for small spans.
In other cases, constructing the upper level, it is necessary to calculate its weight load and provide a strong and reliable rack-mount system.
Reinforced concrete
Most often used in the construction of multi-storey buildings to overlap the first, second floor. Firstly, they are already ready in the form of hollow plates arrive at the construction site. Secondly, installation is carried out only with the help of machines and mechanisms, which greatly facilitates and accelerates the construction process.
These plates are laid on supporting structures and crossbars. Products are cemented with a fine sand fraction. There should be no air chambers, as this will significantly reduce the heat and noise insulation of the building. Warming is made with mineral wool, which is a non-combustible and environmentally friendly material.
Floor slabs between the first floor and the second are produced of certain standards, therefore, according to the architectural design, they can lie directly on the supporting structures, the main thing is that they overlap by at least 15 cm. This is due to the fact that the internal reinforcement of the slab has clamps at the ends of 10 see. They do not work in tension-compression, but serve only as an integral part of the reinforcing link.
The main reinforcement is located between the voids and has a fairly high class of steel and a section diameter. Typically, reinforced concrete systems rely on supporting walls or a crossbar, which has a base in the form of a series of columns or itself rests on walls. One way or another, the plates should be laid only taking into account the step of the columns and observing all norms.
Precast Monolithic
Similar technologies are implemented using the construction of a structural grid of overlap (a structure that is designed for strength and bending), the voids are filled with lightweight porous concrete (expanded clay, gas and foam concrete).
Concrete works for compression (in this case, its fragility is taken into account), and reinforcement for tensile and deflection, so after installing the blocks, the overlap area is additionally covered with a reinforcing mesh. Further, the surface is poured with concrete, and after complete drying is covered with heat and sound insulating materials. Most often used for insulation expanded polystyrene or expanded clay.
A similar construction technology is suitable for low-rise types of buildings. Due to the length of the construction process, a very good heat and noise insulation of the room is achieved, and the specific gravity of the floor is less.
According to their technical and structural characteristics, porous blocks do not lose to reinforced concrete slabs. Such a house will be cool in summer and hot in winter. It is wrong if the air temperature in a building changes dramatically from external factors.
Working moments
Which overlap is better or worse, is decided individually. It is better to trust a good architect who knows exactly where the middle ground is.
A huge role is played by the installation of the ceiling with beams on the first floor: speed, labor costs, material characteristics and other main features prescribed in SNiP.
In addition to all of the above indicators of overlap, its specific gravity affects the total weight of the entire structure, which affects the choice of foundation. It, in turn, also has several types - it depends on the type of building, its weight and foundation.
The cost of the foundation is about 30% of all construction costs, therefore, by reducing the weight of the floors, you can reduce the load of the building on the base and, accordingly, the cost of construction as a whole.
The insulation of the floor of the first floor is most often done with basalt wool, which is non-combustible and non-toxic. Waterproofing is made with roofing material and resins. The lowest floor should be protected as much as possible from moisture and heat loss, because the slightest freezing will lead to unwanted condensation and the appearance of moisture, rot.
What to consider?
The attic and mezzanine floors are additionally covered with a vapor barrier film. Before the erection of the ceiling of the first floor, the foundation is double waterproofed, but moisture is still formed as a result of the temperature difference of the external and internal spaces, so its level should be built according to all the rules and requirements.
Also, despite the advantages, various types of floors have disadvantages. For example, monolithic structures require a team of workers and special equipment. And in the case of concrete mortar, it will be necessary to expect its solidification to continue work for about a month.
The same wooden systems, although easier to install, imply mandatory processing with special compounds, and the service life is shorter.
Conclusion
Regardless of what type of floor will be erected, the main thing is to comply with all the norms and phased requirements of construction, since the slightest deviation from the norm can lead to undesirable consequences, up to the destruction of the structure.
Buildings in which construction rules were violated are not accepted for operation, because it is contrary to standards and life-threatening.
In addition, during the installation process on the site must comply with labor protection and living standards. The class of reinforcement, wood, and the brand of cement should in no case be changed. Each characteristic is taken into account by the architect and agreed in the design organizations.
Also, the developer cannot independently decide on changes in the construction of the building, i.e., for example, instead of reinforced concrete floor slabs, put metal on the ground floor. In any case, an informed decision and coordination with the architect are necessary. Only adherence to technology will avoid errors during construction and guarantee the reliability of the building.