Analysis of the selection of possible solutions to reduce energy demand and costs of thermal modernization measures for building no. 4 of the national university “Zaporizhzhia Polytechnic”

Abstract

The article presents an analysis of technical and organizational-technological solutions aimed at reducing the energy demand of the educational building No. 4 of Zaporizhzhia Polytechnic National University (64 Universytetska Street, Zaporizhzhia). The relevance of the study is обусловed by the significant deviation of the actual thermal performance characteristics of the building envelope from the minimum requirements of Ukrainian State Building Codes (DBN), as well as by the high integral energy consumption indicators typical of buildings constructed under outdated standards, as noted in both domestic and international research. The purpose of the study is to substantiate the rational selection of a set of thermal modernization measures based on a comparative analysis of their energy performance and organizational-economic feasibility, taking into account phased implementation without interrupting the educational process.

The initial building parameters were adopted according to the energy certification results and calculation materials: conditioned area – 6545.11 m², heated area – 5950.10 m², total volume – 24,114.97 m³, heated volume – 17,938.68 m³; the building was assigned energy efficiency class G. The thermal performance analysis of the building envelope revealed critically low values of reduced thermal resistance: for external walls (1605.115 m²) R = 0.291 m²·K/W with a required value of 3.5 m²·K/W; for the combined roof (1794.65 m²) R = 0.611 m²·K/W with a required value of 6.0 m²·K/W; for the slab above the unheated basement (544.6 m²) R = 0.387 m²·K/W with a required value of 4.0 m²·K/W; for glazed structures (1476.237 m²) R = 0.543 m²·K/W with a required value of 0.7 m²·K/W. The calculation of heat loss components and annual heating energy demand was performed in accordance with DSTU 9190:2022, distinguishing transmission and ventilation components, which made it possible to identify priority directions for energy demand reduction and justify the effectiveness of modernization packages. The following thermal modernization options were considered: façade insulation with 200 mm mineral wool, roof insulation of 300 mm, insulation of the slab above the basement, joint sealing and infiltration reduction, modernization of glazing systems, installation of an individual heating substation (IHS) with weather-compensated control and hydraulic balancing, and application of heat recovery systems. It was demonstrated that the greatest impact on reducing energy demand is achieved through comprehensive envelope modernization combined with engineering system upgrades and consumption management.

Additionally, the feasibility of applying modern organizational and technological methodologies to reduce cost risks and indirect expenses was substantiated, including Lean/LPS, BIM/VDC coordination with clash detection, and industrialized (modular) retrofit approaches. These methods increase schedule and budget predictability and support phased implementation of measures. The obtained results can be used in the development of thermal modernization programs for educational buildings, preparation of energy passports, and design solutions for the reconstruction of public buildings in line with sustainable development requirements.