The demand for up to date information and design 'tools' to help architects design more sustainable buildings is rapidly expanding. This demand has led to use various ecological assessment tools as support tools for the design process. The absence of adequate tools which contribute to early stages, as well as the additional costs of tardy modifications, has led us to propose an eco-design support tool. This tool is based on a methodology named “Eco-Model (EM) Method” that focuses on the ecological approaches of a building. This method proposes to consider environmental friendly solutions from the first sketches by proposing a number of micro-solutions, called here Eco-Model or “EM”. Subsequently, the study presents the first contour of software based on an EM approach. Thus, the various actors of the design team will be able to browse the useful information for their green projects and so collaborate to optimize the building design.