Component and facility layout plays an important role in the design and usability of many engineering products and systems as mechanical design, process plan, management and architecture including ship compartment layout. Generally, layout problems are formulated and solved on a case by case basis and, as far as we know, there is no general method to specify the similarities and characteristics of each problem. Then, this paper proposes an innovative generic approach in order to describe, formulate and solve layout problems. This approach suggests in particular a new classification of layout components, introducing the concept of "virtual" component. Moreover, in order to propose to the designer an optimal spatial arrangement in a reasonable time, this paper presents an interactive optimization strategy for solving layout problems.