Purpose: This study aims to answer the ‘what’ and ‘how’ questions about the key role players’ influence on the overall productivity outcomes in the lifecycle of residential buildings procured through the traditional route. Design/methodology/approach: A mix of exploratory and descriptive research methods was used to obtain feedback from 179 role-players involved in various phases of the residential building lifecycle (RBLC) in New Zealand. Empirical data were analysed using content analysis, multi-attribute method and Friedman’s two-way analysis of variance. Findings: Results showed that designers, building owners, main contractors and project managers were the greatest influencers of the productivity outcomes in the RBLC. The priority drivers of these key role-players’ influences on the RBLC productivity outcomes comprised poor brief interpretation, inclination to lowest tender, inadequate prior risk analysis and miscommunication of owner’s requirements and preferences to service providers, respectively. By taking proactive steps to redress their productivity inhibiting acts/omissions as identified in this study, the various role-players could contribute to significant improvement of productivity outcomes in the building lifecycle. Research limitations/implications: It was not possible to interview all participants that made up the representative random samples from each role-player group due largely to workload related excuses. As a result, the findings and the conclusions may not be generalised beyond the study scope. However, the study achieved its purpose, as the main intent was to provide hypothetical constructs that could guide further confirmatory/experimental studies for residential buildings as well as for other building types. Practical implications: A succinct and easy-to-follow model was developed as implementation pathway for operationalising the key findings of the study in the industry. The model highlights the Owner-Architect-Contractor Influence Triangle (OACIT) as the 20 per cent of the solutions that could deliver 80 per cent of the productivity improvement in the RBLC. Originality/value: This study re-examines productivity issues not only from a life-cycle perspective but also from the perspectives of the majority of the key role-players. In addition, the OACIT concept offers a novel productivity improvement tool; it stresses that productivity in the traditionally procured building lifecycle could be optimised if the architect could focus greater attention on brief articulation and the issuance and review of design and specification information. Also, the owner should adopt productivity-enhancing procurement and contract strategies and emphasise more on value-addition and less on lowest tender price.