Damage assessment from very high resolution (VHR) remote sensing imagery plays a fundamental role in the delineation of the impact caused by catastrophic events. To date internationally accepted standard guidelines on how to assess damages to building using vertical imagery have not yet been developed. This study therefore proposes a building damage scale and related interpretation guidelines to be operationally adopted as a standard by the main stakeholderstailored to analyses based on VHR remote sensed vertical imagery. Preliminarily, some of the damage scales used for building damage assessment by the main satellite-based emergency mapping services have been analysed and discussed. A quantitative thematic accuracy analysis based on the open accessible crisis datasets related to the earthquake occurred in Central Italy in August 2016 has been carried out. The results highlight that by using VHR remotely sensed images it is not possible to directly apply damage classification scales addressing slight structural damages (e.g. the lowest grades proposed by EMS-'98). The paper demonstrates that using different damage classes and detailing the interpretation guidelines with operational examples is essential to increase the thematic accuracy of the analysis.