The aim of the project is to increase the energy efficiency of the public building V. Kudirkos str. 99, Šiauliai, for the purpose of treatment, in order to achieve the energy efficiency of the building in class B, to reduce the CO2 emissions of greenhouse gases into the atmosphere and to ensure compliance of treatment-related infrastructure with hygiene standards. During the project, the building of the cooking unit in the 2nd century, insulated walls, roof, replaced part of the windows, external doors, equipped with ventilation system with recuperation will be renovated. After the implementation of the project, it is planned to save about 36.73 % of the cost of heat energy and reach the building’s energy efficiency class B.