Multi-storey buildings: principles and features of construction

Classification of number of storeys of buildings

The following classification of residential buildings is distinguished, which differ in the number of floors:

• Low-rise (1 - 3). Most often these include individual residential buildings. The height of the building, as a rule, does not exceed 12 meters;
• Mid-rise (3-5). The height of the floors is 15 meters - this is a standard five-story building;
• High number of storeys (6-10). The building is 30 meters high;
• Multi-storey (10 - 25):

a) Category I - up to 50 meters. Buildings with a maximum level of 17-18 floors;

c) Category II - up to 75 meters. The height of a 15-storey building is approximately 55 meters;

c) Category III - up to 100 meters. Such buildings have a maximum of about 25 floors.

The number of storeys of a building is calculated solely by the number of above-ground floors. When calculating the number of storeys, not only the size from floor to ceiling is taken into account, but also the size of inter-floor ceilings.

Installation process

Once all the necessary data has been received, you can purchase all the parts for the lightning rod and begin its construction. It is necessary to carefully inspect the roof and select the highest point on it. If we are talking about a flat roof, then it can be the roof of a house that is designed to go onto the roof. The lightning rod is fixed at this point. Its role can be an ordinary metal pin or a piece of copper fittings. The cross section is displayed using the calculator. The height of the mast must be sufficient to prevent lightning from striking other roof elements. If necessary, the lightning rod mast is fixed with guy wires to prevent it from being blown away by wind and lightning.

Advice! There must be a dielectric gasket between the roof and the mast rod, which will prevent the lightning discharge from going further.

Not a metal pipe, but a wooden beam can be used as a mast. It is on this that the lightning rod must be secured. The latter is connected to the intermediate link of the lightning rod, which should consist of large-diameter copper wire. The lightning rod cable must be routed to the ground via the shortest route. In this case, an excellent solution would be to use a rainwater collection system as a box. in this case, you won’t have to worry about the cable being torn off by the wind.

Near the house, at the point where the cable will be lowered, it is necessary to dig a pit. Its depth should be no more than 80 cm. Moreover, its location is selected four or three meters from the house. It is better to choose a place where people rarely walk and cars are not parked. After this, metal pins in the form of triangle vertices are driven into the ground. They must be connected to each other by means of a metal strip or corner, which are welded on top. The length of the rod must be at least two meters, and the distance between them is calculated on a calculator. The thickness of the lightning rod fittings must be at least 12 mm. The wire coming from the lightning rod is connected to ground. Next, the pit can be buried. A video of the lightning rod installation process is below.

Apartment buildings. Number of floors and height of buildings

In modern projects, the “golden mean” is considered to be a height of one floor of 2.8-3.3 m.

The following types of multi-storey buildings are distinguished:

• Panel. Belongs to the budget series. It has a high construction speed, but poor heat and sound insulation. The maximum number of storeys is about 25, depending on the design. In a living room, the height from floor to ceiling is 2.5 - 2.8 m, depending on the size of the panels.
• Brick. The construction speed is quite low, since construction requires high costs. Thermal and sound insulation indicators are much higher than panel ones. The optimal possible number of floors is 10. The height of each is on average 2.8 - 3 m.
• Monolithic. These buildings are quite diverse, because everything depends on the load-bearing capacity of concrete. They have high seismic resistance. To improve heat and sound insulation during construction, brickwork can be used. Allows the construction of about 160 floors. Height from floor to ceiling 3 - 3.3 m.

Fire safety of a multi-storey residential building

The transition from the construction of mid-rise buildings to multi-storey buildings is associated with the need for mandatory installation of elevators and reliable fire safety.

, fire evacuation of the population.
Both of these factors are specific to multi-storey residential buildings
, and the greater the height of the building, the more significant their influence on the feasibility and cost-effectiveness of space-planning solutions.

Ensuring the safety of people is achieved by planning (Fig. 22) and technical means of localizing and isolating the fire source from the entire volume of the building, preventing the spread of smoke throughout the building and providing emergency escape routes. Requirements for the safety of escape routes in case of fire increase with the number of floors. There are three groups of requirements: for 6-9-story, 10-16-story and houses above 16 floors. The least stringent requirements for escape routes are in buildings with a height of 6-9 floors. This is explained by the fact that their height coincides with the height of auto-mechanical stairs, which serve as a reliable means of city fire-fighting services for emergency evacuation of people.

In the largest cities of the country, which have fire-fighting services equipped with auto-mechanical stairs up to 50 m high, the above measures for organizing emergency escape routes are allowed to be provided in buildings with a height of 10 floors with a total area of ​​apartments on the floor of the section up to 270 m2. An additional fire safety requirement for the design of such buildings is necessary fire-breaking devices in staircases in the middle of the building height or through 5 floors in height. The cut is a fireproof wall one floor high.

As the main measure to ensure safe evacuation in buildings with a height of 10 or more floors, the standards regulate the construction of smoke-free staircases with lateral natural lighting. Smoke-freeness is created by space-planning or engineering measures.

Space-planning measures include the arrangement of an open air zone on the evacuation route before entering the evacuation staircase or the use of semi-open cold staircases. The air zone is an open transition in the form of a loggia or balcony from the closed space of a residential floor (section) to the closed space of an isolated staircase. Doors on the escape route are designed to be self-closing, fireproof, with sealed doorways and opening towards the evacuation direction.

An engineering and technical measure to ensure smoke-free conditions is the forced removal of smoke from the staircase space. Forced smoke removal is provided by an exhaust ventilation system that creates air pressure in the staircase of at least 20 Pa, but not more than 100 Pa. Smoke removal shafts are located near the staircase, and their sections are calculated based on the conditions for removing smoke not only from the staircase, but also from the adjacent hall and corridor. The system for turning on smoke exhaust fans is double: automatic - from smoke detection sensors (smoke detectors) and remote - from buttons.

Smoke protection ventilation systems consist of smoke removal shafts equipped with centrifugal electric fans, air supply channels, an air intake ventilation chamber and a smoke removal fan exhaust pipe. The smoke-free space of staircases, elevator shafts and halls is ensured by the creation of excess air pressure in them (relative to the corridor on the floor with the fire), which helps remove toxic combustion products and smoke from the corridor. In the corridors, at a height of 1.8 m, there are openings leading to the smoke exhaust duct. The air supply to the staircase and elevator shafts comes from above from ventilation chambers, which are usually placed on attic floors or coverings. The air intake and smoke exhaust openings are located at a distance from each other of at least 5 m in plan and 3 m in height to prevent combustion products from entering the air supply system.

Smoke exhaust shaft enclosures are designed to be fireproof with a fire resistance limit of at least 1 hour and an air permeation resistance of at least 1.33 m2hPa/kg. The entrance to evacuation staircases of this type is usually organized from the elevator hall through a gateway with self-closing doors.

In addition to the main means of fire safety, which is a smoke-free staircase, a number of additional measures are provided in multi-storey buildings, which include the installation of a wide (at least 1.2 m) blind partition in the loggia, fire-proof passages to adjacent sections, exhaust ventilation of locks and elevator halls . In smoke-free stairwells with air pressure, as an additional safety measure, fire breaks are installed every 5-6 floors along the height of the building.

Smoke-free stairs with an air zone provide safe evacuation in emergency conditions, but are not convenient enough for use during normal operation, especially in winter. Therefore, they are often abandoned, installing in a section one smoke staircase for normal operation conditions and 1-2 open external evacuation staircases.

Residential building elevators are designed with a passenger load capacity of 400 and 630 kg. The speed of elevators in buildings up to 16 floors inclusive is 1 m/s, above 16 floors - 1.5 m/s. The number of elevators is assigned depending on the number of floors of the building, taking into account the number of residents on the floor of the building (section). In a 6-10-storey building there is one elevator per section, and in an 11-12-storey building there are two elevators with a lifting capacity of 400 kg, in 13-16-storey buildings with the number of people living on the section floor up to 30 people. two are also used (400 and 630 kg), and up to 40 people. — three elevators (2–400 kg and 1–630 kg). In buildings with 17 or more floors, the number of elevators is determined according to a special calculation.

Elevators are located within the elevator hall in the middle zone of the floor (section). The minimum size of the width of the hall area in front of the elevator with a load capacity of 630 kg is taken when opening the cabins on the wide side - 1.85, on the narrow side - 2.5 m.

The height of a 12-story building! — Bunker I.V. Stalin

because what is not shown in the plan will be recognized as an unauthorized structure and must be demolished or re-approved.

Without permission, that is, before the plan is approved and documents are received, work should not begin, otherwise serious problems may arise. In order to find out exactly what documents will be required to start construction, you should read the “Code of Rules for Design and Construction SP 11-III-99”.

In order to obtain permission, you need to contact the BTI or the city architectural department to provide:

• application for planning permission;
• documents establishing the right to use the site;
• certificate of field determination of boundaries, placement of buildings, etc.;
• cadastral plan of the site;
• House project.

Once issued, the permit is valid for 10 years.