The operation concerns the energy upgrading of the social structure building of the Municipality of Lamia on 58 Tymfristou Kalvos Street in Lamia The objective is for this four-level and multi-purpose municipal building to become energy efficient and to reach a high energy class of at least B with expected energy savings of the order of 72 °C. Brief description of the energy upgrading interventions that have been proposed by the relevant MEA study and the EPCs and which will be implemented within the framework of the operation1 Insulation of roofs and gates2 Perimeter external thermal insulation 3 Replacement of existing frames with new aluminum with single or double glazing of high energy efficiency Installation of external shades4 Installation of direct discharge air conditioners with a very high efficiency class A at least and discrete control per space5 Installation of ventilation systems with energy recovery to a degree greater than 706 Replacement of all its luminaires with new high energy efficiency LED technology and all electrical panels with new specifications ELOT HD384 in terms of safety and functionality 7 Replacement of old oil boilers with new low-temperature gas oil boilers with a high efficiency of up to 94 °C, as well as the equipment of boilers with the installation of new low-power electronic circulators with new components and new electrical automation power boards8 Installation of an external temperature compensation system in both boilers as well as thermostatic valves in all radiators for total space autonomy9 Installation of a solar thermal system to cover part of the annual heating and water consumption needs for the Guesthouse