According to current seismic design codes, structures are designed to exhibit an elastic behaviour or slight damage in case of frequent (low intensity) seismic events. Conversely, in the case of rare (high intensity) seismic events, a more relevant widespread of damage is allowed. In fact, according to the latter case, structures are typically designed to concentrate the seismic damage into dissipative fuses, whose ductility and energy dissipation capacity is properly designed through the adoption of specific detailing rules. This approach allows the achievement of the safety requirements, but with the drawback of leading to considerable damage to the structural components and large residual drifts, which can significantly compromise the building's reparability. These aspects lead, in many cases, to unacceptable direct (i.e., repair costs) and indirect (i.e., business interruption) losses. To overcome these drawbacks, many recent efforts aimed at enhancing and developing innovative seismic resilient structures to reduce structural damage and repair time. Among others, steel Moment Resisting Frames (MRFs) equipped with friction devices in beam-to-column joints have emerged as a promising and effective solution able to dissipate the seismic input energy while also ensuring the damage-free behaviour of the system. In this direction, relevant research studies have been carried out within the RFCS-FREEDAM research project, demonstrating the high potential of friction joints to drastically reduce the structural damage to steel structures, hence guaranteeing a fast and cheap reparability of the structure even in the aftermath of severe seismic events. The FREEDAM research project has addressed all the issues related to the behaviour of friction joints by providing design rules, a broad set of experimental results, FE modelling strategies, analytical tools, and standardised kits of elements to be applied in beam-to-column joints of steel structures. Within this context, the free from damage technology developed during the research project FREEDAM will be implemented in a demonstration building erected at the University Campus of Salerno, which represents a step forward in the available technologies for the seismic protection of steel buildings. The main objective is to provide awareness about the competitiveness of a free from damage building and the increases in performance levels preserving human lives and reducing the interruption of the functionality of the building after severe earthquakes. In this framework, the present paper illustrates the design and numerical modelling in OpenSees of the demonstration building. Since a sophisticated 3D modelling of the structure is carried out, the Graphical User Interface (GUI) STKO (Scientific ToolKit for OpenSees) is employed. In particular, static, pushover and time-history analyses are performed to assess both the global seismic behaviour of the building and the local response of the friction connections. Furthermore, Incremental Dynamic Analyses (IDAs) are performed to derive the demand samples for the engineering demand parameters of interest while accounting for the record-to-record variability.