Objectives: to report the experience of using architectural designs of a hospital for a historical documentary research. Methods: report of the experience of the methodological route of using architectural designs of a model hospital from 1974 to 2002. Results: after being spread on a worksheet, the projects of interest were selected, enabling the data arrangement, where the analytical chart was applied, containing: context; authorship; authenticity/ reliability; nature of the text and preliminary analysis. The findings were grouped by pertinence and similarity, resulting in the construction of categories of analysis. Final Considerations: architectural design is a challenging source, both for its pursuit, since it took two and a half years until it was legally licensed, as well as for involving specific terminologies and symbology of its own. A special attention should be given to the selection criteria, organization and analysis of the document, and sharing the access of unusual sources with the health area, like this one, so as to stimulate the development of research.