||The construction industry is one of the largest consumers of natural resources and one of the main generators of construction and demolition waste (CDW). Thus, the incorporation of recycled aggregates in construction is highly relevant to achieve sustainability in the construction industry. However, recycling of CDW is only feasible if aggregates are competitive in relation to new construction materials. This work focuses on a Portuguese company that manages the CDW generated by its demolition works, and aims at increasing the efficiency of the production process of recycled aggregates. The main objective is to propose the implementation of improvement actions based on lean management following the DMAIC cycle (Define - Measure - Analyze - Improve - Control) methodology, an organized and sequential method for solving problems using various tools and methodologies from the six sigma management philosophy. The study of recycling operations at the company led to identify lean wastes, understand their root causes and propose improvement strategies and respective forms of maintenance. The proposed improvement measures were designed in the future value stream mapping showing increased production capacity, reduction of lead time and consequently enhanced quality of the aggregates, lower production costs and strengthening of the company competitiveness.