This paper addresses the problem of nodes localization in wireless ad hoc networks. Two types of nodes are considered: nodes with self-locating capability like GPS and nodes with no self-locating capability. For the last ones it is thus important to infer a position which will be retrieved from the position of the neighbor’s nodes. The precision of this information clearly depends on the environment and may not be very accurate. We propose a method which consists in selecting and processing only nodes that are likely to enhance the accuracy of an estimated position. We focus our approach on defining a hull, made up of neighboring nodes, as a key element of position accuracy enhancement. The improvements of using such a method are then validated by a set of simulations.