Experimental study of the thermal-energy performance of an insulated vegetal façade under summer conditions in a continental mediterranean climate

• A full-scale insulated vegetal façade was monitored in a Mediterranean climate.
• The effect of the vegetation is very positive particularly in the warmest hours.
• The maximum temperature time lag enables the utilization of the natural ventilation.
• Vegetal façades entail a reduction of operating temperature favouring users' comfort.
• Vegetal façades are passive cooling strategies that reduce the consumption of energy.

The use of vegetal systems in façades affects the reduction of the buildings' energy demand, the attenuation of the urban heat island (UHI) and the filtration of pollutants present in the air. Even so, up to now the knowledge about the effect of this type of systems on the thermal performance of insulated façades is limited. This article presents the results of an experimental study carried out in a vegetal façade located in a continental Mediterranean climate zone. The objective is to study the effect of a vegetal finishing, formed by plants and substrate, on the thermal-energy performance of an insulated façade under summer conditions.To this effect, the thermal data obtained from two full-scale experimental mock-ups of the same dimensions and composition of the enclosure and only different in the south façade's enclosure where one incorporates a vegetation layer are compared and analysed.The results show that, in spite of the high thermal resistance of the enclosure, the effect of the vegetation is very positive, particularly in the warmer hours of the day. Therefore, vegetal façades can be used as a passive cooling strategy, reducing the consumption of energy for refrigeration and improving the comfort conditions of the users.