Multiformalism approaches and automatic model generation are challenging issues in the context of the analysis of critical systems for which formal verification and validation are mandatory. Reusable model transformations may reduce the skill level required in formal modeling, time and cost of the analysis process, and they may support the integration among different formal languages. This paper investigates how the relationship existing between different classes of formal languages may be exploited to define new model transformations by extending existing definitions. Specifically, the inheritance relationship is considered with the ultimate goal of achieving formalisms integration also by developing proper reusable model transformations. This idea is applied to the integration between Repairable Fault Trees and Generalized Stochastic Petri Nets, where the inheritance relationship between Fault Trees and Repairable Fault Trees is the basis to dene inheritable model transformations. The described techniques are demonstrated on the availability model of a modern railway controller.