This paper describes a computational tool for the efficient study of failure in brittle heterogeneous materials. By means of several examples, it is demonstrated that the proposed tool is adequate for the analysis of materials that show localized failure modes. This case is particular since the main non-linearities concentrate in a small area compared to the whole specimen. The use of the method is preferred when the mesoscopic structure plays a crucial role during failure processes and needs to be fully taken into account in order to accurately tackle damage growth and propagation in the material. The present strategy is based on a Domain decomposition technique. Its performance is improved by selectively processing inelastic regions and reducing the number of operations in the remaining elastic areas. A four point bending test and the fracturing of a heterogeneous concrete specimen are presented as illustrations. They demonstrate that computational costs can be significantly reduced when the proposed strategy is applied to damage analysis.