Environmentally friendly opaque ventilated façade for wall retrofit: One year of in-field analysis in Mediterranean climate

The paper discusses the environmental and thermal characterization of an innovative opaque ventilated façade designed for the refurbishment of the old European building stock. It is characterized by components with high degree of recycled materials, with reversible structural dry connections for an easy assembly and disassembly. The thermo-physical characterization is based on more than one year of in-field continuous monitoring, carried out in a full-scale test-room placed in Mediterranean climate. The behavior of the designed system (test area of 15 m2) is compared with a not-insulated wall, representative of the European reference stock, and also with a wall with vacuum insulation panels. The developed methodological approach allows comparing the different walls under the same boundary conditions, also when these are monitored during different periods, Many benefits can be achieved by the application of designed system, such as stable and less daily fluctuant inner surface temperature with a reduction of the winter outgoing heat flux. The experimental time lag and decrement factor indicate good inertial properties and, during the summer, the proposed system causes temperature drops of more than 10 °C during the sunniest hours. The findings demonstrate that the solution is able to meet both objectives for realizing low-energy-demand building: energy efficiency and low impact over the whole life cycle point of view.