The proposed project concerns the energy upgrading works to be carried out in buildings of the Municipality of Athens and specifically in the School Complex on Eratyras Street In the School Complex on Eptahalkou and Alkaiou Streets In the School Complex on Kypseli and Rhenia Streets In the School Complex on Liosia and Voda Streets 2 School Complexes In the School Complex on Orfeos and Achniades Streets In the Office Building of the Municipality of Athens Liosia 22 In the Office Building of the Municipality of Athens 16The energy upgrading in the shell of the buildings includes the following interventions Thermal insulation of the shell roofs Application of cold materials on the walls of the buildings Replacing the frames Repair of the windows Replacement of the glazing of the windows Installation of the shading systemIn the study of the architectural interventions, the following interventions were taken into account.