OFFICE BUILDING EXPO 2000 - PHASE 4

PROJECT: "Office building EXPO 2000 - phase IV"

Summary of the project

„Office building EXPO 2000 - phase IV" is located at “N.Y. Vaptsarov” Blvd. in Sofia and constitutes the fourth stage of the ambitious construction development „Business complex „Expo 2000“. Phases I, II and III are executed and fully operational. Phase III and IV are designed as a single architectural image and are executed through a blind wall connection. The Employer is "Еxpo 2000 Real Estate" EOOD and "Raiffeisen Property Holding International” GmbH. The architectural design is created by the Austrian architectural studios "Hoffmann Janz" and “u.m.a. Architectur” with a leading designer arch. Ernst Unterluggauer. The main contractor is "Strabag" EAD and the project management is assigned to “Bavaria Aircondition Engineering” OOD.

The building has a total built-up area of around 23 000 m² and offers to its visitors modern conveniences, comfort and security achieved by a luxury interior and functionality in the separation of the areas, high quality of used construction materials and technologies for execution of the installations and equipment in the offices, underground parking on two levels with enough parking places, access control system and 24-hours security and video monitoring.

Access to the building is provided on one side from “N. Y. Vaptzarov” boulevard and on the other side – from “At. Dukov” street. Entry and exit points for traffic are provided through the existing ramps in phases I and III. Due to its strategic location the complex offers accessibility by private and public transport.

Modern architecture and dynamic silhouette contribute to the attractive and representative appearance of the building. In terms of architecture Phase 4 of „Expo 2000“ consists of a high-rise 8-storey part of the building and complementary two crossing wings (6 or 7 stories) . There are two underground parking levels with a capacity of 267 cars. The underground parking lots servicing the occupants of the four buildings in the complex are connected which facilitates the exploitation and access to the buildings.

The façade of the building consists of a light metal structure incorporating solid, transparent, openable and fixed elements. The arrangement of the façade panels is based on a 150-cm grid which allows for a flexible division of the interior space.

The cladding panels are designed in accordance with the concept for materials and colour (Cembrit) implemented in phase III on the one hand and on the other hand - the darker colours of these materials are used as well in the facade arrangement.

The front part of the main building is architecturally connected to the boulevard and the entrance area is emphasized through the two-storey arcade on each side which is supported on inclined columns.

Two-storey high entrance hall is completely glazed at the front side. The main access point is integrated into the facade through a canopy construction which continues through the main entrance lobby providing access to the office areas located from ground floor to level 7, as well as to the underground parking. The lobby is designed and executed in compliance with state-of-the-art standards for aesthetics and functionality by implementation of green walls, a modern reception desk and waiting area. The materials used include natural stone and wood covering on the floor and the walls, and the proper location of elevators, staircases and sanitary premises provides easy access even with people with disabilities.

The main communication between the separate levels, as well as the connection between building installations is provided through the main core which includes 4 lifts, 1 of them for the firefighting, and 4 escape staircases with access to the underground parking lots. In addition, there is an additional lift connecting the two basement levels and the main lobby on the ground floor.

The office floors allow for a flexible division of office spaces and natural lighting by providing an option for installation of partitions at every 1.5m along the façade.

The heating and cooling system of the building relies on multifunctional air-cooled heat pumps located on the roof. These are able to provide simultaneous and independent flow of the required energy for heating and cooling through the system of chilled ceiling panels, active chilled beams and fan coil units. Considering the two-storey height of the main lobby there is provided floor heating, as well as channel fan coil units. 

The office areas are separated into zones. Each separate zone is controlled by a thermostat which delivers a signal to the six-way control valves in order to ensure a proper selection of air-conditioning regime: cooling, heating or switch-off.

Provision of fresh air for the office premises is carried out by two air handling units located on the roof. The air is supplied through chilled beams located in the suspended ceiling along the perimeter of the building.

A particular system has been designed for the underground parking – it includes supply, exhaust and jet fans for extraction of processed air from the parking lots on levels B1 and B2, as well as for heat and smoke exhaust in case of a fire. Part of the ventilation systems in the garage shall be controlled through “CO” (carbon oxide) sensors which shall detect the level of vehicles’ exhaust fumes.

Parts of the roof are executed as green areas and the vegetation thereof is provided as facade greenery on the eastern elevation of the lower part of the building and represents a visual connection with the adjacent landscaping.

Lighting of the office areas is provided through energy efficient LED standing lamps standing with sensors for motion and luminance control. The zones around the central core are provided with LED linear luminaries installed in the suspended ceiling. Separate areas of the building are also equipped with light detectors that also improve the energy consumption values of the building.

All systems are provided with automatic control of their functionality via the implemented building management system.

The majority of the outdoor space is provided with intensive greenery, partially with high-rise vegetation species.

On the terraces of the crossing wings roofs are executed the so-called "green islands" with intensive green areas suitable for planting smaller trees.

The last floor is will be with extensive green area. There is located a technical room with area of 300 sq.m and a technical equipment platform.

On the territory of Expo 2000, phase 4 there is envisaged area for a cafe-restaurant. Near the business complex there are additional catering and accommodation facilities, retail areas, sport and leisure amenities. There is forthcoming rehabilitation of the road infrastructure which shall ensure a better traffic flow.

All materials used for construction comply with the criteria for sustainable construction certification in terms of energy efficiency, low level of dangerous emissions and are accompanied by the respective declaration of conformity.

The building is expected to be awarded with a platinum certificate as per the standards of the sustainable development rating system LEED.