Effective minimisation of construction material waste has demonstrated that environmental pollution arising from construction activities can be reduced. Yet, there is insufficient knowledge on the role of architects in minimising waste, especially at the design phase. The purpose of this article is to identify the causes, barriers, approaches, driving factors to waste minimisation and to investigate strategies employed by architects at the design phase. This study adopted a survey questionnaire with both open and close-ended questions to elicit information from architects in Akure, Ondo State, Nigeria. Empirical results indicate that the major cause of waste at the design phase is the client's last minutes changes to design. Lack of training and design for flexibility and adaptability were the top barrier and approach to construction waste minimisation respectively. The driving factors were training, waste management policy and legislation while the top three strategies employed by the architects are modular coordination, proper detailing and market survey. Findings recommend that a design checklist be created and implemented, that waste minimisation options be considered and that architects take more responsibility for their actions during the design phase.