The main purpose of the fire wall is to limit the area of fire, as well as reduce the damage caused by fire. If such structures are available, it is possible to preserve the burning building and premises even before the arrival of firefighters. In the absence of such structures or their incorrect installation, you can encounter a fairly rapid spread of fire and collapse of the walls. This is only the smallest damage, much more terrible consequences can be human casualties. Therefore, before the construction of residential and industrial buildings, you should familiarize yourself with the features of fire walls that will allow you to save human lives and preserve property in the event of a fire.
The main types of fire walls
Fire wall is classified by the method of placement in the building. Thus, such structures may be external or internal. Such walls can also be classified by load perception, they can be self-supporting or supporting. In the first case, the wall perceives the load from its weight and transfers it to the foundation beams. Whereas bearing walls perceive not only their own weight, but also the mass of ceilings, coatings of other building structures.
It is worth noting that such designs are also classified according to the actual fire resistance limit, which depends on the design. If work on the construction of walls was carried out according to the technological regulations, then they should be built to the entire height of the building, structure, ensuring the non-proliferation of fire in adjacent compartments. This also applies to the unilateral collapse of the building, as well as the building from the side of the fire. Walls should have a height of construction or be erected on the principle of fire protection of the first type, ensuring the exclusion of the spread of fire in adjacent compartments horizontally. Such structures are based on the foundation or in the base beams, crossing floors and structures.
For reference
The fire wall can be installed on the frame structure of a building or structure, which are built from non-combustible materials and meet certain requirements, among them: a high fire resistance of the structure and fire resistance of the mount. The implementation of the first factor will ensure the stability of the wall, the structures on which it is based, as well as the fixation nodes between them. These nodes must have a fire resistance limit that will not be lower than that characteristic of a fire-resistant fence.
Fire fighting device
The fire wall should rise about 60 cm or more above the building. This is true if one of the components of the non-attic or attic coating is made of materials of groups G3 or G4. The roof is an exception. Such a wall should rise 30 cm or more if the components of the uncracked and attic floors are made of materials of groups G1 or G2. In this case, the roof again acts as an exception.
Such walls may not rise above the roof if all coating elements are made of non-combustible materials. If the outer walls belong to the following fire hazard classes: K1, K2, and K3, then the wall must cross these structures and go 30 cm beyond the outer plane of the wall.
Sometimes the construction of the outer walls is carried out using non-combustible materials with tape glazing. In this case, fire-fighting structures must separate the glazing, among other things, it is allowed that these structures do not go beyond the outer plane of the wall.
Construction Features
The fire wall and its external parts may have doors, windows, and also gates that are not rated by fire resistance limits. Moreover, the distance above the roof of the adjacent compartment should not be less than 8 m vertically. As for the horizontal surface, this value decreases to 4 m. When the building is divided into fire compartments, the wall that is in the wider and higher compartment should have the qualities of incombustibility.
The main types of walls
Considering the types of fire walls, it is necessary to highlight the difference in their design. These products can be made of piece blocks or bricks. Among other things, they can be wireframe. In the latter case, the internal space can be filled with piece material or panels, then the design will be called frame-panel.
If we are talking about the walls of piece products, then the limit of their fire resistance meets the requirements of the standards. In this case, the wall should have a width of 0.5 bricks. As a rule, fire walls have a thickness of 25, 38 or 51 cm. In this case, the fire resistance exceeds REI 150. The joints of walls and coatings, floors are made so that the fire resistance does not depend on these characteristics of floors and coatings. But if a frame wall was built, then more stringent requirements are imposed on it, because the fire resistance limits depend not only on the thickness, but also on the joints of the frame.
In case of fire, the crossbar will be exposed to flame from three sides. In order to determine the fire resistance limit, it is necessary to calculate this parameter, which is characteristic of each joint assembly. The final value is taken in accordance with the lowest indicator.
Design features of the wall of the first type
Fire walls of the 1st type have certain design features. In this case, the building materials of the roof should consist of non-combustible materials, but firewalls can go beyond the level of the roof. If the structural elements were made of slow-burning materials, then the firewall rises 300 mm above the roof. If the walls of the building are made of flammable building materials, then firewalls cross the walls and extend outside the building by 600 mm.
Features of fire walls of the second type
Type 2 fire wall should be designed on the foundation, cross the entire building from top to bottom. Even if the wall meets the fire resistance limit that is characteristic of the partition of the first type, it is distinguished from the partition by the presence of bases. Fire doors are installed in the openings of such walls. During the reconstruction of the building, it is possible to increase the degree of fire resistance of the structure through the use of chemical materials, namely:
- plasters;
- impregnation;
- paints and other compounds.
The described fire walls in the building must be made of non-combustible materials, have a high degree of gas tightness. The walls are built to distinguish between parts of the building with different fire loads.
Firewall Features
Fire walls and partitions differ. The latter are vertical fences, which are designed to separate the premises within one floor. Their function is to delay the spread of fire within one floor. Such structures must be located in the places of possible accumulation of mixtures, which may be explosive. They are also installed in niches for communications, warehouses, basements, canals, elevator shafts, which can reduce potential damage in the event of a fire.
Conclusion
The installation of fire walls should be accompanied by high-quality sealing of the gaps between the panels, walls and ceilings of the building. The barriers should be completely empty. In the process of work, special fire-fighting foam is used, which is then covered with plaster based on cement and sand.