Retrofitting using a dynamic envelope to ensure thermal comfort, energy savings and low environmental impact in Mediterranean climates

The paper presents an experimental and analytic study on multi-storey residential buildings without thermal insulation that were constructed before the introduction of energy saving standards (Italian Law 373/1976).Several activities were carried out to identify the optimal retrofit in terms of comfort, energy consumption and environmental impact: typological analysis of 70 buildings in the province of Macerata (Central Italy) and energy analysis of representative case studies; monitoring of a selected case study during summer and winter; thermal simulation of the building in dynamic conditions with EnergyPlus software and calibration of the virtual model by comparison with experimental results; parametric analyses to predict the effect of various retrofit solutions on comfort and energy consumption; environmental impact on the different solutions.It was possible to identify the optimal retrofit solutions for the external vertical and horizontal envelopes. The study showed that the most effective strategy is the insulation of the external vertical wall. The introduction of an external ventilated coating was found to be the optimal solution in a temperate climate.

► Optimal retrofit solution for the vertical and the horizontal envelope.
► The greatest benefits are obtained by insulating the vertical wall.
► Necessity to develop a dynamic envelope for the hot season.
► External ventilated coating ensures comfort, energy saving, low environmental impact.