In the early stage of creation, the architect tests his working hypotheses by making many adjustments while designing. During the sketching phase, the existing modelling tools are not compatible with the iterative nature of this process. So the challenge lies in the definition of a model which will allow the whole creative process with its various coming and going during the phase of conception. In this article, we are going to define a data structure model allowing the simultaneous exploration of several possible solutions, which seems more in line with a creation process.