Across the globe, the corollary of Green Cost Premium (GCP) obstructs the implementation of Sustainable Buildings (SB). Extensive studies into GCP proliferate, but the research norms rarely traversed theoretical contexts of GCP. The purpose of this paper was to explore the drivers of GCP from the contexts of the prevailing practice of SB using the theoretical lens of practice theory. Secondary literature comprising mainly peer-reviewed publications spanning 20years was critically reviewed. The results show some uncertainty regarding the effect of prevailing practice on the size of GCP due to the dearth of empirical studies. Secondary literature, however, showed that GCP is liable to variations in practice related to the level of knowledge and the implementation processes. The knowledge domain argued that the scope of GCP depends on regional issues including misperceptions, cost management deficiencies and sustainability accounting gaps. During implementation, GCP could also modify in response to changes in cost drivers, factors limiting innovative processes and challenges and barriers in the project environment. Engagements with practice have, however failed to embed this understanding into SB project implementation decisions and dynamics, as limited documented efforts aimed at mitigating the GCP exist. The paper offers a non-conventional perspective for assessing the dynamics of converging regional practices in SB that can contribute to GCP as well as lower the GCP when the practices are improved. GCP is susceptible to practice variations and answers to projects practices across regions. This portrays that the GCP can lessen through innovation of practice elements such as competencies and inputs (materials and procedures). The elements of scientific inquiry for GCP must be disconnected from currently established knowledge about SB systems to regional practices related to knowledge and procedures.