Purpose – The purpose of this paper is to examine green building legislation requirements and practices in the construction project execution stage within the context of the South African construction industry. The rationale for this examination rests with the perception that the implementation of green practices (per se) has been recognised as being “behind” the legislation enacted to control the design and construction of green buildings. Design/methodology/approach – The research process consisted of a literature review to identify existing green building legislation and practices applicable to the project execution phase. This was supported by a sequential mixed-method research approach, which involved a survey of contracting companies based in the Western Cape Province of South Africa. Purposive sampling was used to undertake focused interviews with management staff and site operatives. Findings – Research findings established a number of issues, not least: a gap between green building practices and legislation requirements; a high degree of unawareness of green building legislation/practices by construction company stakeholders; selective implementation of health and safety legislative requirements; that management staff had a more “positive” attitude to green building practices than site-based staff who tended to be less motivated and open to such practices. Research limitations/implications – Results from this study are considered generalisable with the sample frame only. Research inference and projections should therefore only be made within this set, and not to the wider population of South African contractors (as this study was limited to the Western Cape Province). Practical implications – Implications from this research are applicable to construction company stakeholders within the population set. Practical considerations include the need to acknowledge a formal commitment to developing a sustainable built environment – especially cognisant of the gap between practices on site and green building legislation requirements. Moreover, this lack of awareness in respect of green building practices and legislation requirements impinges upon several wider areas, not least: construction company stakeholders’ positioning, health and safety practices; managerial and operational staff perceptions, and stakeholders’ willingness and motivation to proactively address these gaps. Social implications – Government bodies and allied professionals in charge of construction industry development are encouraged to consider the implementation of green building legislation requirements on construction sites. This reflection should encourage engagement through formative legislative provision and transparent awareness campaigns. Originality/value – This work is original insofar as it directly addresses the alignment of legislation to current practices within the context of the South African construction industry. However, similar exercises have been undertaken on green building legislation in other countries such as USA, UK and Australia.