Engineering (design, construction and supervision) for energy renovation of multi-family residential buildings in Burgas in connection with the procedure "Support for sustainable energy renovation of the residential building stock – Stage I OP 27: Burgas, Izgrev residential complex, bl. 44

Multi-family residential building with administrative address: Burgas, Izgrev residential complex, bl.44 and has an identifier 07079.501.44.1,2,3 according to the KKRR of Burgas. The residential building is of III (third) category within the meaning of Art. 137, para. 1 item 3 letter "c" of the ZUT and Art. 6, para. 3 item 2 of Ordinance No. 1 of July 30, 2003 on the nomenclature of types of construction and is private property. The building has a total built-up area according to ZUT of 11122.49 sq.m. and is a block, with 6 entrances with 8 residential floors and one basement floor with storage rooms. The building was built in 1977. The nomenclature by which the building was constructed is Bn - VIII - -Rs. The terrain on which the building is founded is flat. There are no indications of weak soils. There is no project for the Engineering Geology part. The permissible soil pressure used in determining the dimensions of the foundations is unknown. Currently, there are no signs of subsidence. The building is constructed with an EPSJ system - frameless panel. Large-panel residential buildings are made entirely of reinforced concrete panels - floors, walls, staircases, etc. Each element is manufactured in factory conditions according to a specific nomenclature. The connection between individual panels is made by means of dowel connections, by welding steel connections embedded in the panels in advance, and subsequently monolithic with cement-sand mortar. Their role is of essential importance in this type of building. The joints between the panels and their sealing are of particular importance. It is assumed that the joints are so-called closed joints. They absorb all deviations from the design position of the prefabricated elements during their production, transportation, and installation. However, sealing materials with a service life shorter than that of the facade panels and the buildings are used, which necessitates periodic repair. Putty was most likely used as a sealing material. In frameless panel buildings, loads from self-weight, useful load, wind, and earthquake are transmitted to the foundations through load-bearing walls. The surveyed building is located in an area with seismic activity according to "Ordinance No-02-20-2 for the design of buildings and structures in seismic areas" from 2012 - VII degree according to MSK. The transverse and longitudinal internal load-bearing wall panels are reinforced concrete with a thickness of 20 cm. The transverse internal partition wall panels are also reinforced concrete with a thickness of 8 cm. The facade wall panels are 20 cm thick. It is assumed that the thickness of the floor panels is 16 cm. The foundation is monolithic, in most cases with large-panel construction it is solved with strip foundations. The zero cycle is solved monolithically. Reinforced concrete panels are mounted on the terraces to the floor panel by means of steel profiles. The roof is reinforced concrete, flat. Rainwater drainage is external, through gutters and downpipes. Reinforced concrete prefabricated parapets connected by means of embedded parts to the roof panel are installed along the entire contour of the roof. The floor of the heated part of the building borders both an unheated basement floor and the external air (bay window). The basement level contains warehouses, corridors, and common areas, which are partially underground. During the period of operation of the building, current repairs related to reconstructions and replacement of materials were carried out, which were partial in different periods of the building's operation. The window frames have been partially replaced. Some of the terraces have been annexed to the premises, and others have been glazed. The existing window frames are morally obsolete, with thermal characteristics not meeting modern energy efficiency requirements. Changes made during operation include: Partial glazing of terraces with metal profile window frames and single glass, PVC or AL window frames with double glazing. Partial replacement of old wooden window frames with new PVC or AL window frames with double glazing. Partial replacement of doors in residential apartments. Periodic refreshing of walls, ceilings, and floors in the building. Openings in n...