Simulation is very useful tool in a planning process. Architects can use it to present their design but also to test them through various software and methods. Hospital building, as a concise combination of form and function, arises from a set of recommended pre-requisites that have a strong foothold in organizational processes and functional flows. If an architect can work and think not only trough drawing and rendering but also trough other media, such as simulation that employs time and user as variables, he achieve much better control over the project. Simulation can also be used for scientific purposes but the problem usually arises from the lack of data necessary for the simulation. Only architecture office that is involved in a project has the building plans in possession. No matter is it a completely new building or a renovation, current i.e. old plans one cannot obtain if he works outside of the responsible office. For simulation, one needs to obtain usable and complete building plans, which requires permission from owner and further request at authority in charge. The process may take some time. When one gets permission to access the archives, he can find the plans most probably in paper form. Scanning the drawings with handheld or regular scanner is also a slow process and the digitized plans need to be adjusted. Since one needs only a few information from the plans for the simulation and not everything depicted with drawings, extracting and editing necessary information is inevitable. In this work, we tried to improve current workflow, especially the process of obtaining data and their preparation for simulation.