Occupant interaction with interior environment in Greek dwellings during summer

User behaviour significantly affects energy consumption simulation estimates, which can consequently influence architectural design decisions at an early stage. Different regional behavioural patterns could, therefore, hinder the applicability of certain architectural and environmental strategies. Through questionnaires analysis and field studies, this study investigates the pattern use of manual control of windows, shading and air condition units, in residential buildings in Greece, during summer. Initial findings of the analysis indicate significant interaction of Greek residents with the building shell, in their effort to maintain comfort.