The field of Sustainable HCI has grown significantly in recent years, yielding a great body of knowledge about sustainable interaction design. However, this knowledge has led to a similar outcome to many other theoretical contributions in the broader domain of HCI: there are only few examples of its direct application to practice. We looked at design research literature from outside of HCI and gathered insights about the work practice of real-world designers to help uncover potential barriers to transferal. In order to increase acceptance and applicability of Sustainable HCI design knowledge for design practice, we argue that Sustainable HCI researchers have to tailor their theoretical contributions to the application domain’s practices in order to reach a broader audience and achieve higher impact. We conclude with recommendations for how to better present and communicate design knowledge to the real world design practitioners.