In order to ascertain the efficiency benefits of green roofs for buildings, a thermodynamic model must be created for the green roof. This work focuses on the thermal properties (conductivity and specific heat capacity) of several media and how they are affected by root growth within them. The results of this research will be used in creating more accurate thermodynamic green roof models. For this experiment, three repetitions of 16 different planting/media combinations were used to monitor the changing thermal properties of the media with environment changes; a focus being on root growth. This experiment shows that the conductance is probably affected by root propagation.