The use of biobased contributes to reducing greenhouse gas emissions, energy consumption and depletion of natural resources by exploiting alternative renewable aggregates. Several studies in the scientific literature have focused on the design of these bio-based materials and the characterization of their properties. The results are in accordance with thermal and hydric performance of these materials for hygrothermal building comfort. Nevertheless, their use remains limited, with questions about their long-term behavior and their performance under implementation and exposure to real climatic conditions. In the case of energetic rehabilitation, these materials are added with existing different materials. It is therefore essential to study the behavior of these biobased materials in the case of multi-layer walls and in the real use conditions to show their efficiency. The objective of this work is to evaluate the hygrothermal behavior of the multilayer wall using different straw bio-based materials developed for building insulation. The experimental building has been designed to simulate the case of external energy renovation. Blocks of straw bio-composites with three different compositions were fixed to each façade of classical concrete blocks with wood fiber panel for comparison purposes. A coating based on lime and limestone sand was then implemented to protect the bio-composite and provide an aesthetic effect. For on- site characterization and monitoring of measurements, the experimental building was instrumented with temperature, humidity and heat flow sensors in the core of the insulation materials, interior, exterior and at the insulators-concrete block interface respectively. The results showed that there is greater humidity in the core of the insulation materials than outside in winter and a smaller difference in summer. This behavior highlights the hygroscopic nature of the bio-based materials. It is also important to note that the behavior of the straw-based materials and wood fibers was similar, with no significant effect of composition.