The design of manufacturing systems is a critical task to be addressed throughout the factory life-cycle phases, including the early design, detailed design, ramp-up, reconfiguration, and monitoring. An efficient and effective system design platform may have a relevant impact on the profitability of industrial companies facing these challenges. Although several commercial applications are available for supporting different activities within the manufacturing system design and operation these stand-alone tools are usually supplied by different software vendors and cannot be easily integrated, thus entailing a massive and time-consuming integration effort. This paper proposes the integration of heterogeneous software tools supporting factory design activities over a common platform. A virtual factory environment, based on a shared data model providing to all the applications a common language to exchange data, is developed. A test case is presented that shows the integration of five methods and the related software tools to support different activities for the design of a manufacturing production line, hence the benefits derived by the application of this integrated approach in industry. © 2013 The Authors.