Currently, most cities' technical and administrative services are organized in silos, thus hindering any holistic approach to urban planning. In the case of urban mobility, they tend to focus only on direct emissions of greenhouse gases and particles harmful to health, but indirect impacts such as material requirement and associated environmental pressures are usually overlooked. This is problematic in a systemic perspective as ecological transitions policies (e.g. development of renewables energies) typically rely on larger metal consumption and imply additional resource constraints. One should therefore check that suggested mobility policies are feasible from a resource point of view. In this context, a prototype tool based on a bottom-up analysis for the city of Lyon was created. The preliminary results show that a main parameter for reducing the impact of urban mobility is the rate of motorized personal vehicle ownership, and that changing the modal share is not enough to have a beneficial effect on all indirect impacts. Another result is that a reduction in vehicle mass through the substitution of steel by aluminium is more environmentally impactful in terms of indirect manufacturing indicators. In the end, the aim of this tool is to be used as a pedagogical model to engage a dialogue with the stakeholders of the territory considered by informing the debate on possible socio-technical alternatives for city/territorial planning.