Predicting project duration with reasonable accuracy is a formidable challenge to industryrnpractitioners and alike. Consequently, several research studies have focused on this subject, andrnthus multiple models have been developed. Notwithstanding the conflicting findings of itsrnpredictive ability, the 50-year-old â€œtime-costâ€ model of Bromilow (BTC) remains the baseline, tornwhich the outcomes of most developed models are compared. The Building and TransportrnConstruction Design Authority (BaTCoDA) had developed a model based on BTC in 1987 forrnbuilding projects but it is hardly used in the industry. The objective of this study, therefore, is tornexamine the validity, and hence the applicability, of the BTC model to estimate contract durationsrnfor public building projects in Addis Ababa, and to propose an alternative model, taking intornconsideration other potentially influential project scope variables on time performance. In thisrnregard, relevant data for 34 public buildings in Addis Ababa, which were completed during thernperiod 2010 and 2019, were collected by an archival analysis. rnThe results of the analysis show that while the BTC model holds true for the projects under thernstudy, a model with a better statistical significance was developed with gross floor area as a solernpredictor variable. The Ï-value and F-value for the BTC was 0.00019 and 18.403 respectively,rnwhile that of the developed model was 0.000076 and 21.734 respectively. Furthermore, thernadjusted R2 for the BTC was 0.397 while that of the developed model was 0.425 which impliesrnthe developed model was a better fit for the data set. Furthermore, the models were compared withrnthe model developed by BaTCoDA and the result shows that the model developed based on grossrnfloor area is superior on account of predictive