Net-zero carbon in construction: what we know and what we do not yet know

This study, adopting the PRISMA framework, identifies and analyses 61 high-quality journal articles related to net-zero carbon in construction. The in-depth analysis focuses on geographical distribution, research methods, multi-level perspectives, and key themes in net-zero construction research, aiming to clarify what we currently know and, importantly, what we still do not yet know about the pursuit of net-zero in the construction sector. The findings reveal geographical disparities, with high-income nations advancing technology integration and policy, while emerging economies focus on foundational capacity and localised solutions. In addition, the methodologies employed in net-zero carbon construction research can be categorised into four main approaches: quantitative modelling, simulation, and analysis; qualitative and mixed methods; and comparative analyses. This review also identifies six main research themes: the roles of technological innovation and digitalisation; the necessity of robust policy and governance; the interplay of economic incentives and barriers; the focus on embodied carbon and material circularity; the practical hurdles of implementation and skills development; and the importance of a lifecycle perspective. Ultimately, this review identifies and elaborates on 11 important themes representing the black boxes of ‘what we do not yet know’, signifying critical priorities for advancing the net-zero construction agenda.