Building performance analysis at the design stage enables assessing the building'srnperformance and the variables that influence it. Simulating the performance of arnbuilding by visualizing how the building will react in response to excitation in a virtualrnenvironment provides designers and respective stakeholders vital information in therndecision-making of buildings. rnNonetheless, a common practice in Ethiopia indicates that an emphasis is placed onrnhow the building appears and is constructed in the project's design phase rather thanrnhow the building will accomplish its intended function and performance requirements.rnDespite the longevity of buildings, analysis of how the building will operate andrnperform its intended function is seldom. rnThis research aims to study the existing practices of building performance simulationrnfor buildings in the design stages for the case of consultants in the architecture,rnengineering, and construction industry of Addis Ababa. The research design employedrna questionnaire as a data collection tool. It gathered information from consultants aboutrntheir approach to design, their tools, use of building performance simulation tools,rnconsideration of uncertainties in their design, and sustainability approaches. For furtherrnvalidation, semi-structured interviews and documentation reviews were used for therncase study analysis. rnIt is found that there is a disparity and underlying lack of understanding of buildingrnperformance fundamentals and analysis methods. For existing simulation practices inrnbuilding projects in Addis Ababa, it is found that local consultants do not do them.rnMoreover, with the infancy of BIM practices in the cityâ€™s consultants, capitalizing onrnthe possible BIM-based building performance simulation of buildings is not foreseeablernunder current circumstances. rnAs a result, this research recommends essential education and training regardingrnbuilding performance to realize its potential in developing buildings with improvedrnperformance and applicable standards and rating systems for sustainability in the localrncontext.