This paper presents the onsite temperature monitoring of ETICS walls located in a Mediterranean climate, looking to compare different conditions and insulation materials. The walls incorporate several insulation products, including vacuum insulation panels. Different finishing coats and orientations were considered. Additionally, a 2D numerical model was used to simulate the transient thermal behaviour of the case study walls.The results show that walls with a greater insulation capacity finished with a white coloured surface were more likely to develop surface condensations, and consequently, microbiological growth. Black walls showed higher temperature amplitudes increasing the risk of the rendering cracking.