Calibrated simulation can be used to evaluate energy conservation measures (ECMs) and identify potential energy savings for building energy retrofits and commissioning. However, it has been limited for use with dynamic simulation tools (e.g., DOE-2 and EnergyPlus) due to its complexity of input variables and output energy data. This study proposes an enhanced signature analysis with percentile expression for model calibration and demonstrates its use for a case-study building, along with significant calibration factors, including: building thermal mass, undocumented exhaust air, and maximum supply air temperature. As a result, the as-built calibrated model was determined to have an overall daily CV(RMSE) of 19.69% and a daily MBE of 6.19%.