5 th International Congress on Construction History ASYMMETRICAL VAULTS IN LATE EUROPEAN GOTHIC: BASEL AND BEBENHAUSEN AS CASE STUDIES Ana López-Mozo 1 , Rosa Senent-Domínguez 2 , Miguel Ángel Alonso- Rodríguez 3 , José Calvo-López 4 and Pau Natividad-Vivó 5 Keywords Late Gothic ribbed vault, stonecutting, Theory and practice of Construction History, prinzipalbogen Abstract In the 15th and 16th centuries a peculiar type of Late-Gothic vault lacking symmetry about longitudinal and transversal axes of the plan appears in at least thirty two buildings throughout Europe; the oldest examples could be located in Poland. They are tierceron vaults with diamond shaped liernes, where the main keystone and the whole or part of diagonal ribs are absent. A number of written European sources include instances of this type of vault: the Frankfurt Lodge Book of Master WG (c. 1560-1572), the Wiener Sammlungen collection (spanning from mid-15th century and the beginning of 16th century) and the Musterbuch of Hans Hammer (last decades of the 15th century). The design of this kind of vault is not simple; it does not seem to arise from a mere process of ribs multiplication. Although some types of Late Gothic vault were developed in particular countries, master masons travelled throughout the continent, an a permanent exchange took place amongst the different lodges. In many occasions, conscious copies of models were likely made, perhaps reflected in travel sketchbooks nowadays missing. Lacking other documents, a method to go beyond superficial resemblance and look for deeper connections is to analyze how the geometrical layout for both plan and volume has been addressed, since methods for deriving overall elevation from plan were only exchanged among masons. This paper deals with two examples of this kind of vault that use the same plan layout to span different types of bay: a square one at a corner of the cloister of Basel cathedral (c. 1440-1645), and a rectangular one at the crossing of the church of Bebenhausen Abbey (c. 1467) (fig. 1). This study, supported by a precise data gathering based on crossing-image photogrammetry, is focused on the layout of the rib network. Although both vaults seem to follow the same design, the geometrical construction of plan and elevation is entirely different. The two cases show an advanced use of Gothic design procedures to solve problems easily. 1 Technical University of Madrid, Spain, ana.lopez.mozo@upm.es 2 Technical University of Madrid, Spain, rosa.senent@upm.es 3 Technical University of Madrid, Spain, miguel.alonso@upm.es 4 Technical University of Cartagena, Spain, jose.calvo@upct.es 5 Technical University of Cartagena, Spain, pau.natividad@upct.es