Energy and microclimatic performance of Mediterranean vernacular buildings: The Sassi district of Matera and the Trulli district of Alberobello

► The experimental research carried out on two examples of vernacular architecture. ► These environments are in condition of comfort even when outside temp is above 35 °C. ► The constant values of indoor temperature do not require air conditioning in summer. ► The seasonal heat storage assured comfort levels by using the simple heating systems.