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Construction materials are the largest flows entering urban areas after water. Using secondary resources—the materials mined when built works are demolished or renewed—could lead to a significant change of urban metabolisms. However, while secondary resources are massively extracted, their use in construction remains limited. Regional planning and projects led by local authorities aim to develop this use, but these initiatives face strong constraints. This article analyses these constraints according to their stage in the material flow chain as well as the scale of action they depend on. We show that important limits lie at the stages of material production and use as well as at national and European levels. Possible action plans for territorial policies carried by regional directorates for the environment (DREAL), regional councils and cities are then outlined.