 The increasing use of smart technology has led to greater interest in energy conservation measures, ECMs, which are becoming more accurate due to advances in energy software and computing power. However, there are still some common mistakes when measuring the accuracy of building energy models, such as using incorrect uncertainty indices or assuming that the models are calibrated when they are not. These errors can lead to a false sense of security that the models are properly calibrated when in fact they may not be. To avoid this, it is important to follow the guidelines set out by organizations like ASHRAE, IPMVP and FEMP, which outline best practices for measuring the accuracy of building energy models. This article was authored by German Ramos-Ruiz and Carlos Fernandez-Banderra.