The aim of this diploma thesis is to prepare the project documentation for a new polyfunctional building designed in the city of Brno. The building consists of a total of four storeys, one of which is underground and three above ground. The underground storey contains a multi-storey car park intended for vehicle parking as well as the technical facilities of the building. The first above-ground storey is used for retail spaces and the main entrance to the building, providing access to the upper floors. The second and third above-ground storeys are intended for administrative purposes. These floors accommodate entrance halls, offices of various sizes, meeting rooms, kitchenettes, and sanitary facilities. The individual storeys are interconnected by a staircase and an elevator, and barrier-free access to the building is ensured. In front of the building, an outdoor parking area is designed, including two parking spaces designated for persons with reduced mobility and orientation. The building is founded using a white tank waterproofing system. The structural system is designed as a reinforced concrete frame, with an external load-bearing envelope made of monolithic reinforced concrete and fitted with a ventilated façade. Internal partitions are formed by drywall constructions, and the staircase core is also designed as a monolithic reinforced concrete wall. The underground storey is formed along its entire perimeter by the walls of the white tank system. The floor structures are designed as monolithic reinforced concrete slabs. The roofs above the building are designed as single-layer flat roofs. Above the second above-ground storey, a semi-intensive green roof with a usable terrace is designed, while above the third above-ground storey, an extensive biosolar green roof is proposed. The façade of the first above-ground storey is designed in a beige colour, while the façades of the second and third above-ground storeys are designed in white.