The transition to a circular economy requires reducing waste and rework in construction projects. Thereby, the evaluation of building circularity in the early design phase is of great importance. However, due to the current design workflow, such practice is hindered because there is not enough information to evaluate building circularity in detail in the early design stages. An improved workflow to emphasize circularity more in the early design phase is thus needed. This research explores the current workflow and designs an improved work procedure with limited information available by incorporating an automated decision support tool to assess early design phase building circularity, aiming to improve the working efficiency and efficacy. This tool has been designed based on interviews and literature studies, and verified and validated with practitioners. This study serves as a starting point to rethink the workflow to improve circularity with current technological potentials.