Ceiling and Roof Construction of the Mosque-cathedral of Córdoba – Decoration, Building and Construction History of the Oldest Extensively Preserved Collection of Roof Timbers in Europe

• Applicants: Dr.-Ing. Felix Arnold; Dr. Thomas Eißing; Professorin Dr. Ulrike Fauerbach
• Subject Area: Architecture, Building and Construction History, Construction Research, Sustainable Building Technology
• Term: since 2026
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 560293676

In the courtyard of the Mosque-Cathedral of Córdoba (Spain), 232 decorated timbers are on display. It is one of the earliest and largest complexes of medieval roof timbers preserved in Europe. The beams, rafters and panels bear witness to at least three construction phases of the main mosque of the Caliphate of Córdoba from the 8th–10th centuries. As part of the project, the timbers, which are complemented by around 100 more in museums and storerooms, are being comprehensively and systematically documented for the first time. They will be studied using a range of methods from natural sciences, engineering and art history. The results make a significant contribution to the understanding of the design, construction and spatial effect of one of the most important sacred spaces in world architecture and at the same time to the history of architecture and building construction at the interface between the Islamic world and Western Europe. As part of the project, the species, origin and chronology of the wood are determined by wood science. During a test campaign, it was possible to prove, for example, that all the boards of a panel were cut from one tree trunk; this broadens the view to previously unexplored details of supply chains and work processes. Thanks to unhindered access to the timbers granted by the cathedral chapter, it is possible to record the cutting, recesses, nails and other structural details of all preserved timbers in great detail. In this way, wood science and building archaeology can jointly record a sequence of the construction processes in time and space: The building, which was founded in 785 on a square ground plan, was first extended to the south around 840 and again in the 960s, before being extended from 11 to 19 naves to the east around two decades later. During renovation work in the 14th century, the original flat ceilings were replaced by open roof constructions, and these were then replaced by suspended vaults in the 18th century. The perception of the space, which is defined by double horseshoe arches, must have been very different in each case; this will be reconstructed and visualized. In addition, all the surviving timbers have carved and colored ornaments as well as traces of appliqués, which together formed complex designs. Remarkably, the decoration of each component was composed individually. To execute them was only possible thanks to geometric preliminary drawings, traces of which, as well as signatures of individual craftsmen, can still be found on many of the panels. The ornamental program will be analyzed in the individual steps of its production, interpreted in terms of art history and placed in the context of Islamic cultural history. The findings of wood science, building archaeology and history of Islamic art will flow together in a jointly compiled catalog, which will be published and also form the basis for further publications.

• DFG Programme: Research Grants