Declarative modeling transforms deeply the task of scene designing by adding to it flexibility, and more creativity and by being more user-friendly. However it's difficult to generalize its use, because it requires too much processing time and memory. A possible way for improving the efficiency of declarative modeling is to parallelize the scene generation process. In this paper, a method for parallelizing the generation of the first solution is presented and applied to hierarchical declarative modeling. It is very important to get the first solution as soon as possible because this solution gives the user the possibility to interactively guide the remaining of the resolution process.