The current trend in the construction industry is construction “without limits”. In projects and implementations, we encounter non-traditional combinations of operational solutions, geometry and materials, which are still approached mainly using the classic standards from the fire safety point of view. The latter does not allow to comprehensively cover all aspects of these specific buildings without a greater degree of subjective simplification. This raises the question of whether, even in these cases, it is still appropriate and safe to use only a standards approach, or whether buildings deviating from traditional construction should be assessed differently – for example, by so-called fire analysis using numerical models. Currently, users still have very little information about the use of these models, and even in the Czech legislation, there is no document recommending how to proceed when using them for the purposes of building fire safety solutions. Numerical models of evacuation and fire analysis are thus currently the most effective tool for impact analysis and preliminary verification of the effectiveness of proposed safety measures. Therefore, it is necessary to deal with their validation and use, with the goal of innovating existing approaches and standardizing numerical models for fire safety assessment of buildings. Furthermore, it is necessary to compare their possibilities and limitations concerning ČSN and to put together a comprehensive information background as a basis for their more active implementation in practice. The presented work thus focuses on the above-mentioned issue and demonstrates its use of application examples of real specific buildings and a set of compiled studies. The work also points out specific shortcomings and simplifications of standard approach methods, based on which verified procedures and recommendations for the incorporation and use of numerical models in fire safety practice are then established.