This article focuses on the experimental investigation of hygrothermal behavior of hemp concrete (HLC) and straw rape concrete (SLC) walls. An experimental device has been developed which makes it possible to analyze several hygrothermal behaviors of building wall under static and dynamic conditions. The monitoring of kinetic of temperature and relative humidity within the wall shows the strong coupled of heat and mass transfer. In case under dynamic conditions, the condensation and evaporation phenomena lead to the damping of variation of temperature within the wall. In addition, the air permeability test and infrared tomography analysis have been done. The both walls have high air permeability and some heterogeneous zones have been highlighted. (C) 2017 Elsevier B.V. All rights reserved.