This article explores possibilities of using fuzzy models as a new research tool in the history of architecture. Namely, Adolf Loos's villas are studied using these models. Fuzzy expert models will be used to analyze the principles of Adolf Loos's work. Rules applied by A. Loos in villa design will be expressed in the form of fuzzy rule bases. The formulation of rules will result from the analysis of individual villa designs and will be based on theoretical concepts pertaining to Loos's work -- in particular, on his designing process drawing on the concept of a Raumplan. Further, the concepts of the theory of architecture, related to a general procedure of construction design, will be utilized. The article also gives examples how to employ fuzzy sets in describing a building and its characteristics.