Recently, planning under temporal uncertainty is becoming a very important and active field within the AI planning community. In this paper we present a new approach to handle planning problems with uncertain duration of actions. The novelty of this approach is that the management of the temporal uncertainty in durative actions is done independently of the planning process itself, which allows us to reduce the problem complexity. The experiments will show that we are able to obtain a plan that satisfies the user requirements for all the tested cases. Consequently, this work can be considered as a promising approach to handle this type of problems.