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The building sector is responsible for a significant part of global energy consumption and greenhouse gas emission. Nowadays, there is a growing interest in the so-called super-insulating materials, particularly Aerogels. The present work examines the performance of novel aerogel blankets obtained thanks to an innovative ambient drying process. Based on these aerogel blankets, two thermal insulation systems are developed: one as external thermal insulation composite system (ETICS) and another one as internal thermal insulation multi-layer system (ITI). The objectives of the current work are to assess the performance of the core material (aerogel blanket) as well as the two developed systems. At a material (core layer) scale, thermal, hydric, and mechanical performance characterizations are carried out. At a system level, in-situ hygrothermal, acoustic, and fire performance characterizations are carried out in real scale test cells. Hygrothermal characterization revealed that the thermal conductivity of the studied blanket is about 0.0165 W/(m.K) in ambient and dry conditions but can increase by up to 40% in a very humid environment (RH > 90%). The integration of the aerogel blanket panels into an interior insulating system, tested in a test-cell located in south of France, show great thermal performance. The U value of the wall decreased from 0.63 W/(m2.K) to 0.33 W/(m2.K)after retrofitting. The in-situ hygrothermal results showed that the external insulation system protects the wall against the moisture risks. For the internally insulated wall, the relative humidity remains lower than 85% even when high moisture generation is present inside the test cell. Concerning the thermal performance, the envelope's thermal transmittance is reduced by more than 80% after applying the insulation systems. The ITI system was tested in-situ to airborne sound insulation (facade), reporting significant acoustic improvement in acoustic insulation: +7 dB, equal to a noise reduction to one quarter compared to the base wall without insulation. The fire test of the ETICS proceeded without any material ignition, while the fire behavior of the internal insulation system depends significantly on the adhesion stability between all single components.

International audience; This study aims at examining the energy behaviour of the buildings' multi-layer exterior wall structures. Most of the studies dealing with this issue have considered a continuous operation of the cooling/heating systems. Our objective here is to find the best wall structure and the number and position of insulation layers within exterior walls for continuous heating, intermittent heating, and no heating operation modes for some commonly used construction materials. Furthermore, among the different materials used, a recently patented insulating coating based on the (super)-insulating materials "Silica Aerogels" is being assessed. Results from a one-dimensional heat transfer numerical model in a multi-layer wall structure are compared to on-site measurements of an experimental set-up, having the new aerogel-based coating, under real weather conditions. The numerical model is then used to carry out all the simulations. Several assessment parameters are used: time lag, decrement factor, energy consumption, and thermal comfort index. Results show that for continuous and no heating cases, the best wall from maximum time lag and minimum decrement factor perspective is dividing the insulation layer into two and placing one at the middle of the wall and one at the exterior surface. For intermittently heated spaces, placing the insulation material as one layer at the interior wall surface is the most efficient from an energy consumption perspective. Also, when using the thermal comfort index for the no heating operation mode, the best performance is achieved when placing the insulation at the interior wall surface. For most of the cases studied, the aerogel-based insulating coating shows better performance than other insulating materials.