The composition of the building is made up of one main body, formed by the volume of its building. A clear horizontal alignment is sought, which is made of facade elements - bay windows, terraces, rails, etc. The selection of colors and the proportioning of the holes and the dense parts on the facades complement the image of the building, clearly emphasizing its residential character. An adequate response to the surrounding environment and the exposure of the facades is sought towards the world directions and the view to Vitosha through spacious balconies with glass railings and wide window openings and showcases in the living rooms. A visual separation of the ground floor from the overall volume of the building was sought by treating the facade in a different way.


The building is designed with an underground floor and six above ground floors, the latter being under roof according to the Territorial Planning Act. The underground level is occupied by independent garages. All residential floors are located in all above-ground floors. The building is served by a centrally located vertical communication core consisting of a staircase and a lift for 10 persons (800 kg of capacity). The access to the individual apartments is through two floor corridors along the length of the building. The corridors determine the location of the dwellings along the two long facades of the building facing east and west. The southern front is occupied by two larger two-bedroom apartments.

The total number of apartments is 45. Each of the apartments contains the following premises:

  • Entrance hall
  • Living room and dining room with kitchenette
  • One or two bedrooms
  • Bathroom-toilets
  • Toilet for three-bedroom dwellings
  • Warehouse space (closet)
  • Balcony

The project provides the required number of 50 parking spaces and garages as follows:

  • At terrain level - 29, through 13 two-level parking systems;
  • In the underground floor - 21, located in separate garages;


The construction of the building is skeletal without rows, with vertical bearing elements of reinforced concrete columns and washers. The enclosing walls are made of 25 cm bricks with thermal insulation of ESP 15 cm. The internal partition walls are 12 cm thick and are made of brick masonry. Roofing and facade panels will be provided with the appropriate insulation and plaster, ensuring comfort, integrity and durability of the structure. The interior layout is a subject of a separate project.

The building will be gasified. Each apartment has an individual gas boiler set on the terrace. It provides domestic hot water for the consumers. The heating is by hot water radiators supplied by the boilers. The air-conditioning of the dwellings can be accomplished by installing air conditioners in the living rooms. A wiring installation is planned for that purpose with fixed place for the external body of the system. Bathroom heating in the winter is provided by electrical heaters for wall mounting.

The water supply for household drinking needs will be from ground plumbing. The supply of hot water to the individual consumers will be individualized through volumetric water heaters - gas boilers mounted on the terraces. Construction of cold and hot water installations is planned. The metering of the water consumed for each consumer will have individual water meter nodes with impulse outlets for remote reading. The discharge of household and rainwater from the building will be in the street sewerage system.

The project treats the following internal electrical installations: lighting, power, bell, television, lightning rod and grounding. The necessary normative lighting is planned according to the Bulgarian State Standard.


The construction of the building is designed as monolithic reinforced concrete. The panels are without beams with a thickness of 22 cm. They are dimensioned by a numerical model using the end elements method as an elastic membrane, non-deformable in its level, point-supported on the columns, and linearly on the washers. To support the drilling over the columns, underpinnings made of reinforcing steel are constructed. The foundation of the residential building is designed with a 60 cm tick baseplate. The sizing is made in the middle of the Winkler ground-based model with a constant of 25 MN/m3 for basic combinations and 90 MN/m3 for special combinations. In seismic terms, the building is secured by reinforced concrete washers and reinforced concrete cores. For this purpose a numerical calculation model (3D) is composed using the end elements method. The resulting earthquake efforts are combined with + and - with static load loading for getting the most unfavorable combination. The building is secured for a seismic impact of the IX degree on the Medvedev-Schoonheier-Karnik scale with Kc = 0,27. High-strength concrete C20/25 class and reinforcing steel B500 are used in the construction of the building.

Water supply and Sanitation

Plumbing installation:

The household water supply is from street water supply under a separate project. The plumbing deviation for the building will be made of high density polyethylene pipes DN75, laid at depth according to the normative requirements - 1.50m under the asphalt road and 1.20m under the lawn. The pipes will be laid in a vertical, non-tightly fortified trench. The disbursed water quantity for the building will be metered by a water meter unit located in a water sampling shaft, located at a distance of 2m from the site's regulation line, developed according to a separate project. The vertical deviations for each apartment are designed to be fitted with water meters for cold water, qn = 1.5 m3/h with impulse outlet for remote reading.

The discharge of the waste water from the building will be in existing sewerage F800 concrete pipes, through SCO DN250 PVC-U pipes. The discharge is through a revision shaft. The disbursed water quantity for the building will be metered by a water meter unit located in a water sampling shaft, located at a distance of 2m from the site's regulation line. The water meter unit is a separate project. The vertical deviations for each apartment are designed to be fitted with water meters for cold water, qn = 1.5 m3/h with impulse outlet for remote reading. Each individual water meter unit includes a stopcock, water meter for 1.5m 3/h and a return valve.

Sewerage installation:

The discharge of household waste and rainwater from the building is in existing sewerage F800 concrete pipes and is through building sewer DN250 PVC-U pipes. The discharge is through a revision shaft. The designation of the waste water quantities is based on the applicable normative documents. The vertical sewerage branches are made of PP pipes. Vertical openings are provided at the height of the first, last and through 3 floors. The drainage of household wastewater and rainwater from the building is through a suspended horizontal sewerage installation. The horizontal suspended sewerage installation will be made of PVC-U pipes and fitting parts. The vertical sewerage branches are 30 cm above the roof for the purpose of sewerage ventilation. Part of the VKK end with anti-vacuum valves - indicated on the drawings. The toilet seats are provided with a lateral drainage, the floor siphons in the sanitary premises of the apartments are DN50 with lateral drainage and water seal.

The drainage of the rainwater is done through external drainage pipes, parts of which on a ground level enter in the horizontal suspended drainage of the building. The drainage of the drain pipes in the suspended sewerage is done through anti-odor valves mounted in the verticals.

The drainage of the adjoining terrain is through linear drains. Their exact location is according to the design part Vertical planning.

The waste water from the site's parking lot passes through a local oil-separator treatment unit located at the location indicated in the drawing, after which it is discharged into the ground embedded horizontal system. The designed oil separator is 10 l/s with a deep mud pit.

Execution of the plumbing and sewerage installations

The cold water installation - verticals and distribution system will be built of polypropylene Stabi pipes. The hot water installation built in the walls of the sanitary facilities will be made of polypropylene pipes PN20 and polypropylene pipes PN 16 for the cold water. The vertical plumbing branches will be insulated with 9 mm insulation and the distribution system with 13 mm insulation. The distribution plumbing installation for BPN and PPN will be suspended at the basement level.

The deviations from the VKK for the sanitary units are 0.98 m high from the ground floor for cold water. The distribution installation shall be laid in the walls of the premises and shall be at a height of 0.63 m from the ground floor for hot water and 0.48 m for cold water. The installation height of the sanitary fittings from the ground floor is as follows:

-Mixing tap for toilet sink-standing-0.85m

-Mixing tap for kitchen sink-standing-0.85m

-Mixer shower-wall-1.00m

-Stopcock for flushing cistern-0.60 m

-1/2" on 3/8" stop valves for standing batteries-0.55m

The sewerage installation in the sanitary premises should be made of PP pipes and fitting parts. Suspended sewerage system should be made of PVC-U pipes and fitting parts. The revision holes’ setting is planned on the height of VKK at a height of 0.80 m from the ground floor of the first, the last and through 3 floors. The VKK go to 30 cm above the ventilation roof. VKK should be built over the roof and ventilation hoods to be fitted above.

The toilet seats are provided with a lateral drainage, the floor siphons in the sanitary premises of the apartments are DN50 with lateral drainage and water seal. The vertical sewerage branches for rainwater located on the façade of the building should be filled with PP pipes and placed in the insulation of the building. The installation of revision holes on the first and the last floor is planned to be along the height of the drainage pipes.


External power supply

The connection of the building to the electrical grid will be carried out according to a stance of the ERP to the GET - two-sectional, located on the facade of the building in a special niche with free access from the outside. The connection will be done with a cable type SAVT 3x120 + 70mm2. 45 new single phase and 2 new three-phase 10/60A electrometers with 63A automatic fuses will be installed in the main electrical panel. The operating power capacity of the facility will be 270.60 kW.

Internal installations

All switchboards will be radially powered by a main switchboard from which all consumers should be power supplied - lighting fixtures, sockets, etc. The installation in the building will be implemented with a PVVM conductor placed in the plaster.

The lighting of corridors and staircases, elevators, garage lighting, as well as the roller shutter for access to the garage area are power supplied by a common consumer splint into the main switchboard.

In a view to the proper allocation of the consumers in the apartments’ distribution units, the respective number of current circuits will be allocated. All fuses will be automatic, fast, in order to increase fire safety.

The fuses will be with defective-current protection for the installation outlets in the bathrooms, as well as the free sockets.

The installation for the sockets will be executed with a conductor of 3x2,5 mm2 section, as it is mandatory to be reset and the installation for the lighting will be executed with a conductor of 3х1,5 mm2 section.

All brackets will be installed at a height of 2,0m from the floor. All the sockets in the rooms and corridors will be installed at a height of 0,4 m from the floor while the ones in the kitchen at the height of 0,7 m or 1,35 m from the floor. The switches and sockets in the bedrooms will be mounted in the middle of the nightstand at a height of 0,6 m on one frame tightly next to each other. This also applies to low-current outputs - telephone jacks and TV outputs.

The location of the lighting fixtures in the rooms will be consistent with the interior, the function of the rooms and the architect's views. Their control will be done with ordinary and serial switches, and the corridors and transition zones with deviator switches. In the stairwell and the common areas the lighting will be controlled by motion detectors. The lighting of the building will be mostly with KLL. LED energy-saving lighting units should be supplied with electronic start-up control equipment. They will be mounted close to each other on one frame when more than one switch is shown at one place. The lighting fixtures are anti-damp in the bathrooms and terraces and the switches will be mounted outside the damp rooms. The switches in these rooms will have built-in defective-current protection.

Garages power supply

The garages with elevation of -3, 10m are supplied with separate cables of type SVT 3x2.5mm2 to their own switchboard from a common consumer bus in a main electrical panel. If necessary, each of the garage switchboards can be re-supplied by the appropriate electrometer on designated floor switchboard. Each of the garage switchboards is fitted with a main fuse and, if necessary, a bus bar with fuses for supplying various consumers - sockets, garage door and others can be built.

Lighting around block spaces

The project envisages the construction of parameter lighting around the block by independent of the electrical grid, autonomous, solar-powered street lamps with LED lighting. The lamps will be with an automatic sensor and will switch on independently with the reduction of the natural lighting. The lamps will be charged in the day time by a solar panel mounted above them which will power supply their own lithium-ion hybrid battery mounted at a height just below the lamp. That lighting will not form costs for the common parts to the future owners of the property.

Evacuation lighting

Evacuation lights will be installed along the corridors and staircases of the building. These lights are with rechargeable batteries and 8W luminaire lamps with an "EXIT" sign and a directional arrow or a "running man" symbol and a directional arrow. They are power supplied by a separate current circuit directly from the main switchboard and switch on when the voltage drops.

Low voltage installations

All outlets of low-voltage installations must be installed at least 0.3m away from the high-voltage outlets or to be screened in order to eliminate interference. The cables for low-voltage installations are laid in a corrugated PVC tube F23mm. A switchboard for low-voltage installations is set up in each housing unit, and the cables pass from the switchboard through a vertical riser to a communication cabinet located near the main electrical panel.

The following low-voltage installations will be executed:

Telephone and internet installation - with UTP4x 2x0,35mm2 cable;

TV installation - with РК75 cable;

Bell and intercom installation - with FTP4x 2x0,50mm2 cable;

Lightning rod and thunder protection installation

The lightning rod and thunder protection installation of the building will consist of 1 lightning protection system located on the roof of the building with the use of an active lightning receiver with overtaking action ES-SAT250 / 1 Receiver for each unit / EC standard UNE 21186 and NF17102 with a radius of 78 m or 156 m diameter at the height of the rod of the current conductor / mast (5 m) with an overtaking time of 60 μs, data according to the instructions given in the nomograms of the manufacturer, in conjunction with Article 86, paragraph 3 of Ordinance 4/2010 / and at a level of protection III.

For each of the both lightning protection systems the down conductors are two made of extruded aluminum conductors F8mm with PVC insulation, placed under the thermo-insulation and protected with vertical strip of rock wool 20 cm/width /Art.123 of Ordinance 4/2010/. Each system also includes 4 steel grounding 14/2000 mm EC142.OUNE202006 standard EC UNE A-42 B, two for each of the down conductors that are interconnected with galvanized splint 40/4mm. If no grounding resistance of less than or equal to 10 Ω /of Ordinance 4/2010/ is achieved, an increase in the number of interconnected groundings is envisaged.

Fire safety

The construction of the building is non-combustible. The evacuation routes are marked with emergency lighting. The staircase is illuminated with KLL and facade windows and it is separated from the floor corridors by fireproof, self-closing doors with a fire resistance of not less than EI 30. Evacuation lights are also provided when changing levels. The installation is laid under the plaster and the cable transitions through the walls are filled with a non-combustible consistency. The main electrical panel is with a metal flip lock.

Safety, hygiene of work

During the exploitation of the object, it is possible to leak electric current as a result of touching current parts or burns due to arcs or breakthrough of insulation or short circuits.


To ensure safety and hygiene, as well as fire safety, the following measures are taken in the exploitation of the project:

The construction of the premises is massive, with monolithic performance.

  • The premises have dimensions and layout, allowing the correct installation and allocation of all installations and equipment.
  • The illumination of the rooms complies with the average illumination standards.
  • The boards are metal, lockable and mounted on a wall.
  • The connection of the incoming and outgoing wires is done by cable shoes, and for the small sections with ан ear and screw connection.
  • Keep a minimum distance of 0.3m between the elements of the electrical installations and the OV and plumbing installations.
  • When operating on the electrical system, disconnect the corresponding current circuit from the switchboard.
  • Additional safety precautions should be taken when using movable stairs.


The building gas installation is provided with 100 mbar - yard grid - from GRT 4/0,1 bar (under another project) to a gas panel with a central shut-off valve. A 100 mbar building gas pipeline is in the common parts, supplying 45 (forty-five) individual gas-regulating and metering panels. Forty-five individual building gas pipelines will be built up to 22 mbar, according to the number of ARH sub-units, supplying forty-five double-circuit gas boilers up to 24 kW (according to part OV) with a closed heating chamber and domestic hot water supply. Emergency gas alarm is also required for each individual building gas installation 2200 mbar.

The building gas installation for the site is the internal gas installations of the consumers in the individual properties which starts after the natural gas metering devices owned by the gas distribution company as well as the yard grid and the gas installation in the common parts of the building supplying the individual gas installations of the consumers.

In the project, the building gas installation are divided according to their working pressure as follows:

  • 100 mbar - yard grid and in common parts of the building;
  • 22 mbar for power supplying of the apartments.


Gas condensing boiler type up to 24kW, two-circuit, with closed chamber. The boilers are designed to provide domestic hot water and heating. The gas boilers have coaxial smoke extraction and are located in thermo-insulated cabinets on the balconies of the respective apartments. Typical technical characteristics of 24kW double-circuit boilers with a closed chamber. Type C gas boiler for the production of hot water for heating and domestic hot water with a closed chamber and a fan receiving combustion air and emitting combustion products through a coaxial flue.

Consumption of natural gas - 2,7 Stm3/h;

Efficiency at nominal thermal power (80/60 ° C) - 96.3%;

Efficiency at 30% load (80/60 ° C) - 103.3%;

Efficiency at nominal thermal power (40/30 ° C) - 104.6%;

Efficiency at 30% load (40/30 ° C) - 109.1%;

Debit of hot sanitary water at DT=30 ° C - 12.2 l/min;

Coaxial flue: Ø100/Ø60 mm

Diameter of the sanitary water pipelines - ½”;

Diameter of the heating pipes - ¾”;

Diameter of the gas pipeline – ¾”;

ЕPower supply - 230 V, 50Hz, 170 W.

Ventilation of a gas boiler type C with a closed chamber

The provided gas boilers for the individual apartments have a combustion chamber insulated from the cabinet. The cabinet in which the gas boiler is located does not require any additional ventilation since its supply of combustion air is supplied through a coaxial flue directly from the atmosphere.

Smoke extraction of a type C gas boiler with a closed chamber

The extraction of the products from the combustion chamber of the gas boiler for the individual apartments is supplied through the coaxial flue and through the facade of the building directly into the atmosphere.

The smoke flues of the gas boilers are installed at least 250 mm below the ceiling, according to the specific requirements of the manufacturer.


The power supply to the building is from the street gas distribution system, which has a working pressure of 4.0 mbar. The gas regulation board is located on the border of the property and its connection to the urban gas regulation board is under another project and it is implemented by the gas distribution company. 100 mbar building gas installation, after the GRT to the central shut-off valve for the site, is executed underground by high density polyethylene pipes - PE-HD 100, SDR11, Æ90х8,5 and seamless steel pipes Æ88,9х4,0 according to BSS EN 10208, according to the drawings. The depth of laying of the underground gas pipeline is at least 0.8 m from the ground level. TCSK is executed on the western facade of the building. TCSK has a 3 "central shut-off valve for the facility and a dismountable connection. After TCSK, the 100mbg building gas installation is executed by seamless steel pipes Æ88,9x4,0; Æ76,1х4,0; Æ60,3х3,6; Æ48,3х3,6; Æ42,3х3,6 and Æ26,9х3,2 according to BSS EN 10208. It is developed in common parts of the building, successively through the basement staircase and vertically for the supply to the floor gas boards. In the common parts of the building, in the section after the TCSK to the floor gas boards, the pipes are installed in a gas-tight connection with the staircase "suitcase", which is part of the provided natural ventilation of the 100MBg building gas installation. In the individual floor gas boards are located the gas regulation and measuring boards for the individual apartments on the respective floor. The 100 mbar building gas installation in the building is vented in total and is executed without the direct connection to the air of the staircase or other areas within it. For that purpose, a fixed louvre grid is installed on the western façade, and then the building gas installation is placed in an installation suitcase that connects to the floor gas board (drawing 01-02/03 and 01-03/03). The "suitcase" is made of non-combustible gypsum board with thickness h=2.5mm. The floor gas boards are ventilated through the floors of the building and through the roof - directly into the atmosphere. The openings in the plates for providing natural ventilation have the following dimensions: 250x200mm at the entrance to the vertical section, 1250x300mm on individual floors and 150x150mm through the roof of the building. The doors of the floor gas boards are made of non-combustible material. For the installation of steel pipes of 100 mbar building gas installation, fastener clamps with insulating elements are used. After welding and mounting on clamps, the pipes are treated with primer and painted to protect against corrosion. The building gas installation with operating voltage = 100 mbar ends with a shut-off tap and a scorching candle after it, which runs through the roof of the building.

Hydraulic dimension of a building gas installation 100 mbar

For the design of a 100 mbar building gas system, a hydraulic calculation is being performed with the respective natural gas flows according to the methodology established on the basis of the "Technical Rules for Gas Installations" - DWGV-TRGI since 1996. Consumption for the whole residential building of 68.8 Stm3/h is taken with a coefficient of simultaneity. The selection of the diameters is such that the loss of pressure from linear and local resistances at the most unfavorable point of the installation is not more than 10% and the gas velocity does not exceed 6 m/s.


The pressure drop from 100 to 22 mbar and the power supply to the individual building gas pipelines is accomplished by gas regulation and metering devices consisting of: 100/22 mbar, 10 Stm3/h and a gas flow meter G4.


The start of the 22 mbar building gas installation is from the output nipple of the commercial metering instrument (gas flow meter). The same are intended to be executed from copper rigid tubes according to BSS EN 1773-84 and EN 1057 with diameters and thicknesses according to the flowcharts according to drawings from 05-01/06 to 05-06/06 and the axonometric diagrams of drawings from 06-01/45 to 06-45/45.

Two methods are used for joining pipes with fittings: soldering with hard silver solder and pressurizers specified for gas installations. After the floor gas boards, the pipes are mounted under mortar/plaster to the gas appliances according to the regulations. The thickness of the screed/plaster over the top forming the copper pipes is at least 15mm. For protection against corrosion, the pipes must be insulated with an insulating strip before being put in a screed or plaster.

Hydraulic dimensioning of individual building gas installations

For the sizing of the individual building gas pipelines, a hydraulic calculation is being carried out according to a methodology established on the basis of the "Technical Rules for Gas Installations" - DWGV-TRGI since 1996, taking into account coefficients of simultaneity. The average consumption is up to q max=2.7 Stm3/h for a gas boiler apartment with a capacity of up to 24 kW. The choice of diameters is such that the loss of pressure from linear and local resistors at the most unfavorable point of the installation is not more than 2 mbar at an inlet pressure of 20 mbar and the speed does not exceed 6 m/s.


This is done by installing a gas detector with a sensor in the Ex execution. The gas detector head is mounted in the common parts of the floor at elevation ± 0.00, and the sensor over the last installed equipment in the floor gas panels above the scrubber crane. The gas analyzer does not control gas supply cut-off equipment but signals when methane is present. The signaling is light and sound, and when triggered, the signaling device sends messages to the concerned parties.

In case of uncontrolled gas leakage in the premises with gas appliances or gas pipelines, an emergency gas alarm is triggered when reaching 10% of the lower explosion limit. Upon reaching 20% of the lower limit of explosivity, the gas detector delivers a control signal to an electromagnetic valve controlled by it which interrupts the gas supply for the respective site. The restoration of the gas supply is done only by manually restarting the solenoid valve after checking and removing the damages detected by the gas installation and the gas appliances by specialized servicing personnel.

The emergency gas signalization is carried out by installing:

A two-stage domestic gas detector with a built-in sensor mounted on a corresponding gas boiler in accordance with the manufacturer's installation instructions; electromagnetic valve - normally closed or normally open. The electromagnetic valve is controlled by a corresponding gas detector. In this way, a complete disconnection of the gas supply to the respective site is ensured. A separate fuse designed to supply the respective domestic gas appliance and the gas detector. A conductor between the gas detector and the solenoid valve providing the control signal.

Heating and air conditioning:

In order to create the necessary normative quality of the habitable environment, the heating of the apartments is provided through double-circuit wall hot water gas boilers. All boilers are designed to process the heat carrier for heating installations as well as for heating water. All boilers will be fitted with external thermostats, antifreeze kit at negative outside temperatures, coaxial fresh air and exhaust gas heaters, circulation pump, expansion tank, safety and shut-off valves. The piping from the boiler to the distribution box falling outside the building will be insulated with a 19mm thick k-flex thermal insulation. The discharge of exhaust gases takes place on the facade of the building. When selecting the room temperatures, the applicable norms have been applied; the temperatures are being selected according to the purpose of the premises. The heating for the building is provided by aluminum heaters with height H350 and H800, the bathrooms in the building will be heated by radiators. All radiators are designed to be equipped with automatic deaerators, radiator valves with a thermostatic head and radiator valves. All radiators will be installed in the locations specified in the technical design. The mounting of the radiators is horizontally done on the respective consoles to the walls of the rooms. The supply of the radiators is made of polyethylene pipes with an aluminum insert F 16х2 in the floor screed. All flexible pipes F 16х2 are laid in a corrugated hose F 23, while the passage through the doors is protected by a pipe 1". The apartment collectors are equipped with spherical valves, automatic deaerators, lever faucet, and mini spherical cranes for any deviation to the heaters and adapters F 16-1/2 ". The collectors will be mounted in collector boxes for embedding.


By the investors’ assignment, the air conditioning is provided by air conditioners "split" systems in the living rooms. These systems operate with direct refrigerant evaporation, all of which are heat pumps with inverter control of the compressors. This type of air-conditioning system also offers heating during the winter season and cooling during the summer season. The single "Split" consists of one indoor and one outdoor unit for the room. The inner and outer bodies are connected with copper tubes. The air conditioners are remote controlled. The outdoor units must be installed as specified in the plans. The indoor units are for high-wall installation. The pipe connections between the indoor and outdoor units must be insulated along with the electric cable and the drainage F20 must be attached to the chute in the wall and/or the insulation of the façade to the outdoor unit. The drainage of the indoor unit is F20mm. The condensate from the indoor units is taken to vertical risers to the nearest drainage /Water Supply and Sewerage project/.



The proposed ventilation of the garages is calculated on the basis of 3 times air exchange. The ventilation is provided with a channel fan with a flow rate of 5600m3/h and a head load of 300Pa. The air intake of the room is 50% of the lower zone through triggers through rectangular ventilation vents mounted on the air duct of 30cm from the KGP and 50% of the upper zone. The transport of the air duct to the disposal of the façade is made of galvanized steel sheet with a thickness of 0,8mm. During the passage of the air ducts through the walls will be installed fire valves with the size of the air duct in the respective area. The compensation of the air is done through openable doors and fugues.


For the sanitary units, suction ventilation is provided by household fans with a flow rate of L=90 m3/h, ensuring the removal of the required amount of air, which is 90 m3/h defined on the basis of an ordinance and its discharge over the roof of the building through a vertical branch Ø160. The transport of the contaminated air to the roof of the building is done by PVC air ducts F110 from each toilet, before each subsequent bath is connected to a pipe F160 (collector).

For the kitchens, the normative amount of air to be discharged is L=180m3/h, which is done by aspirators with the corresponding flow rate. The discharge of air is done through masonry chimneys.


According to its functional purpose, the building is classified as functional fire hazard class F1 and subclass F1.3 according to Table 1 of Art. 8 of Ordinance №Iz-1971 for the STPNOBP. The entire reinforced concrete structure of the building is non-combustible. Metal and wooden load-bearing elements are not being used. The access to the roof of the building is provided through the exit of the staircase at the last level by a sun roof. The evacuation staircase is naturally illuminated from the western façade with a space of > 5% of the staircase area, in accordance with the requirements of Art. 50 from NSTPNOBP. The staircase of the building is separated from the corridors in accordance with the requirements of Art. 47, para. 1 from NSTPNOBP. The width of the stairs is 1.20 m. The end evacuation exit of the building is with a door opening in the direction of evacuation with dimensions 120/220, which is in accordance with the requirements of Art. 41 of the NSTPNOBP.


The external pedestrian areas and the entrance and communication spaces in the building comply with the requirements of Ordinance No. 4 on the Civil Protection Act. According to Art. 35 (02) of Ordinance No. 4, an apartment for persons with disabilities is provided at elevation +2.90, apartment A02. Within the framework of Regulation VII-64, an accessible parking space is provided according to Art. 19 (1), para. 2 of Ordinance No. 4 on the Civil Protection Act.