This article explores how the combination of research approaches in Research Through Design (RTD) can contribute to generating applicable urban design knowledge. The article is based on learnings from the ‘Really cooling water bodies in cities’ project, a pragmatist RTD combining post-positivist, constructivist and transformative/participatory approaches along six design iterations. The results indicate that the combination of research approaches in RTD can contribute to generating applicable urban design knowledge when the approaches are carefully chosen and combined as to provide feedback on each other, based on a coherent rationale driven by clear research questions and goals.